Skip to main content

Full text of "ASME BPVC IV (2007): Boiler and Pressure Vessel Code, Part IV, Rules for Construction of Heating Boilers"

See other formats


mm- 



mm~m * * * "rfr- ■ T"r-'-1iiEHir."-TAr 







NOTICE OF INCORPORATION 

United States Legal Document 

£3P All citizens and residents are hereby advised that 
this is a legally binding document duly incorporated by 
reference and that failure to comply with such 
requirements as hereby detailed within may subject you 
to criminal or civil penalties under the law. Ignorance of 
the law shall not excuse noncompliance and it is the 
responsibility of the citizens to inform themselves as to 
the laws that are enacted in the United States of America 
and in the states and cities contained therein. ~*&k 

* * 

ASME BPVC IV (2007), Boiler & Pressure Vessel 
Code, Rules for Construction of Heating 
Boilers, as required by the States of Alaska, 
Arizona, California, Illinois, Iowa, Kansas, 
Michigan, Missouri, Nebraska, New Hampshire, 
New Jersey, North Dakota, Ohio, Oregon, Utah, 
Wisconsin, et. alia. 



*mr-V ¥^£% Tm^\ 



ss:^ 



. >r ' ,:i-- 










.•-•••••-** 



^% : MS 



/ ^r 




1ULES FOR CONSTRUC 
HEATING BOILERS 



UJIttlilH 



Mechanical Enginee 



AN INTERNATIONAL CODE 



2007 ASME Boiler & 
Pressure Vessel Code 



nfi 



k «k» v . a5.. AA2V 
.>*A t AT-)/ fUM 







3S&SS& 



;«w 



s™*$* 



*&,' 



, i" .-*£ ' 



l§K^K??E 



Ail* 









asstxk 






ilBBlll 



g& 



w, 



a^^^i 



^aOl 






ss§ si 



Ml 



a * 



¥T 



TO*?!* 

SB 



B 



s^ 



s £**£** ~<s 



ii« 



m 



m 



Mechanical Engineers 



AN INTERNATIONAL CODE 



2007 ASME Boiler & 
Pressure Vessel Code 



2007 Edition 



July 1, 2007 



IV 



RULES FOR CONSTRUCTION 
OF HEATING BOILERS 

ASME Boiler and Pressure Vessel Committee 

Subcommittee on Heating Boilers 



' The American Society of 
*® Mechanical Engineers 



Date of Issuance: July 1, 2007 
(Includes all Addenda dated July 2006 and earlier) 



This international code or standard was developed under procedures accredited as meeting the criteria for American National 
Standards and it is an American National Standard. The Standards Committee that approved the code or standard was balanced 
to assure that individuals from competent and concerned interests have had an opportunity to participate. The proposed code 
or standard was made available for public review and comment that provides an opportunity for additional public input from 
industry, academia, regulatory agencies, and the public-at-large. 

ASME does not "approve," "rate," or "endorse" any item, construction, proprietary device, or activity. 

ASME does not take any position with respect to the validity of any patent rights asserted in connection with any items 
mentioned in this document, and does not undertake to insure anyone utilizing a standard against liability for infringement of 
any applicable letters patent, nor assume any such liability. Users of a code or standard are expressly advised that determination 
of the validity of any such patent rights, and the risk of infringement of such rights, is entirely their own responsibility. 

Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted as government 
or industry endorsement of this code or standard. 

ASME accepts responsibility for only those interpretations of this document issued in accordance with the established ASME 
procedures and policies, which precludes the issuance of interpretations by individuals. 

The footnotes in this document are part of this American National Standard. 




ASME collective membership mark 

©®©@©©@©© 

©©©©©©©©© 
©®©@©@© 

The above ASME symbols are registered in the U.S. Patent Office. 

"ASME" is the trademark of the American Society of Mechanical Engineers. 

The Specifications published and copyrighted by the American Society for Testing and Materials 
are reproduced with the Society's permission. 

No part of this document may be reproduced in any form, in an electronic retrieval system or 
otherwise, without the prior written permission of the publisher. 

Library of Congress Catalog Card Number: 56-3934 
Printed in the United States of America 

Adopted by the Council of the American Society of Mechanical Engineers, 1914. 
Revised 1940, 1941, 1943, 1946, 1949, 1952, 1953, 1956, 1959, 1962, 1965, 1968, 1971, 1974, 1977, 1980, 1983, 1986, 

1989, 1992, 1995, 1998, 2001, 2004, 2007 

The American Society of Mechanical Engineers 
Three Park Avenue, New York, NY 10016-5990 

Copyright © 2007 by 

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS 

All Rights Reserved 



2007 ASME 
BOILER AND PRESSURE VESSEL CODE 



SECTIONS 

I Rules for Construction of Power Boilers 

II Materials 

Part A — Ferrous Material Specifications 

Part B — Nonferrous Material Specifications 

Part C — Specifications for Welding Rods, Electrodes, and Filler Metals 

Part D — Properties (Customary) 

Part D — Properties (Metric) 

III Rules for Construction of Nuclear Facility Components 

Subsection NCA — General Requirements for Division 1 and Division 2 
Division 1 

Subsection NB — Class 1 Components 

Subsection NC — Class 2 Components 

Subsection ND — Class 3 Components 

Subsection NE — Class MC Components 

Subsection NF — Supports 

Subsection NG — Core Support Structures 

Subsection NH — Class 1 Components in Elevated Temperature Service 

Appendices 

Division 2 — Code for Concrete Containments 

Division 3 — Containments for Transportation and Storage of Spent Nuclear Fuel 
and High Level Radioactive Material and Waste 

IV Rules for Construction of Heating Boilers 

V Nondestructive Examination 

VI Recommended Rules for the Care and Operation of Heating Boilers 

VII Recommended Guidelines for the Care of Power Boilers 

VIII Rules for Construction of Pressure Vessels 

Division 1 

Division 2 — Alternative Rules 

Division 3 — Alternative Rules for Construction of High Pressure Vessels 

DC Welding and Brazing Qualifications 

X Fiber-Reinforced Plastic Pressure Vessels 

XI Rules for Inservice Inspection of Nuclear Power Plant Components 

XII Rules for Construction and Continued Service of Transport Tanks 



ADDENDA 

Colored-sheet Addenda, which include additions and 
revisions to individual Sections of the Code, are published 
annually and will be sent automatically to purchasers of 
the applicable Sections up to the publication of the 2010 
Code. The 2007 Code is available only in the loose-leaf 
format; accordingly, the Addenda will be issued in the 
loose-leaf, replacement-page format. 

INTERPRETATIONS 

ASME issues written replies to inquiries concerning 
interpretation of technical aspects of the Code. The Inter- 
pretations for each individual Section will be published 
separately and will be included as part of the update service 
to that Section. Interpretations of Section III, Divisions 1 
and 2, will be included with the update service to Subsec- 
tion NCA. 



Interpretations of the Code are distributed annually in 
July with the issuance of the edition and subse- 
quent addenda. Interpretations posted in January at 
www.cstools.asme.org/interpretations are included in the 
July distribution. 

CODE CASES 

The Boiler and Pressure Vessel Committee meets regu- 
larly to consider proposed additions and revisions to the 
Code and to formulate Cases to clarify the intent of existing 
requirements or provide, when the need is urgent, rules 
for materials or constructions not covered by existing Code 
rules. Those Cases that have been adopted will appear 
in the appropriate 2007 Code Cases book: "Boilers and 
Pressure Vessels" and "Nuclear Components." Supple- 
ments will be sent automatically to the purchasers of the 
Code Cases books up to the publication of the 2010 Code. 



CONTENTS 



Foreword xv 

Statements of Policy xvii 

Personnel xix 

ASTM Personnel xxxi 

Preamble xxxiii 

Summary of Changes xxxv 

List of Changes in BC Order xxxvi 

PART HG GENERAL REQUIREMENTS FOR ALL MATERIALS OF 

CONSTRUCTION 1 

Article 1 Scope and Service Restrictions 1 

HG-100 Scope 1 

HG-101 Service Restrictions 1 

HG-102 Units 1 

Article 2 Material Requirements 3 

HG-200 General Material Requirements 3 

HG-201 Specific Material Requirements 3 

Article 3 Design 4 

HG-300 Design Pressure 4 

HG-301 Cylindrical Parts Under Internal Pressure 4 

HG-305 Formed Heads, Pressure on Concave Side 4 

HG-306 Formed Heads, Pressure on Convex Side 5 

HG-307 Flat Heads 5 

HG-309 Spherically Dished Covers (Bolted Heads) 9 

HG-3 12 Cylindrical Parts Under External Pressure 11 

HG-320 Openings in Boilers, General Requirements 14 

HG-3 21 Reinforcement Required for Openings in Shells and Formed Heads 15 

HG-323 Flanged-In Openings in Formed Heads 17 

HG-325 Reinforcement Required for Openings in Flat Heads 17 

HG-326 Limits of Metal Available for Reinforcement 19 

HG-327 Strength of Reinforcement 21 

HG-328 Reinforcement for Multiple Openings 21 

HG-330 Inspection and Access Openings 21 

HG-340 Stayed Surfaces 22 

HG-341 Staybolts 24 

HG-342 Dimensions of Stays 24 

HG-343 Dimensions of Diagonal Stays 24 

HG-345 Staying of Heads 26 

HG-346 Tubesheets With Firetubes Used as Stays 27 

HG-350 Ligaments 27 

HG-360 Requirements for Tube Holes and Tube Attachments 31 

HG-370 External Piping Connections 32 

Article 4 Pressure Relieving Devices 33 

HG-400 Pressure Relieving Valve Requirements 33 

HG-401 Minimum Requirements for Safety and Safety Relief Valves 34 

HG-402 Discharge Capacities of Safety and Safety Relief Valves 36 



HG-403 
HG-405 

Article 5 
HG-500 
HG-501 
HG-502 
HG-503 
HG-504 
HG-505 
HG-506 
HG-510 
HG-512 
HG-515 
HG-520 
HG-530 
HG-531 
HG-532 
HG-533 
HG-534 
HG-540 

Article 6 
HG-600 
HG-601 
HG-602 
HG-603 
HG-604 
HG-605 
HG-606 
HG-607 
HG-610 
HG-611 
HG-612 
HG-613 
HG-614 
HG-615 
HG-620 
HG-621 
HG-630 
HG-631 
HG-632 
HG-633 
HG-634 
HG-640 

Article 7 
HG-700 
HG-701 
HG-703 
HG-705 
HG-707 
HG-708 
HG-709 
HG-710 
HG-715 
HG-716 



Heating Surface 38 

Temperature and Pressure Safety Relief Valves 39 

Tests, Inspection, and Stamping 40 

Proof Tests to Establish Design Pressure 40 

General 40 

Procedure 41 

Tests of Parts Subject to Collapse 43 

Tests of Duplicate Parts 43 

Test Gages 43 

Inspection of Proof Tests 43 

Hydrostatic Tests 43 

Safety and Safety Relief Valve Accumulation Tests 43 

Inspection Tests and Certification of Boilers 43 

Master and Partial Data Reports 45 

Stamping of Boilers 46 

Stamping of Parts and Accessories 49 

Stamping of Field Assembled Wrought Boilers 49 

Inspection and Stamping of Field Assembled Boiler Pressure Parts 49 

Field-Assembled Cast Iron Boilers 50 

Code Symbol Stamps 50 

Instruments, Fittings, and Controls 52 

General 52 

For Steam Heating Boilers 52 

Steam Gages 52 

Water Gage Glasses 52 

Water Column and Water Level Control Pipes 53 

Pressure Control 53 

Automatic Low- Water Fuel Cutoff and /or Water Feeding Device 53 

Modular Steam Heating Boilers 53 

For Hot Water Heating or Hot Water Supply Boilers 54 

Pressure or Altitude Gages 54 

Thermometers 54 

Temperature Control 54 

Low- Water Fuel Cutoff 54 

Modular Hot Water Heating Boilers 54 

For All Boilers 54 

Instruments, Fittings, and Controls Mounted Inside Boiler Jackets 54 

Electric Wiring 55 

Electrical Code Compliance 55 

Type Circuitry to Be Used 55 

Limit Controls 55 

Shutdown Switches and Circuit Breakers 55 

Controls and Heat Generating Apparatus 55 

Installation Requirements 56 

Installation Requirements, All Boilers 56 

Mounting Safety and Safety Relief Valves 56 

Piping 56 

Feedwater and Makeup Water Connections 57 

Oil Heaters 57 

Storage Tanks for Hot Water Supply Systems 57 

Provisions for Thermal Expansion in Hot Water Systems 57 

Stop Valves 61 

Bottom Blowoff and Drain Valves 61 

Modular Boilers 62 



HG-720 
HG-725 



Figures 

HG-307 

HG-309 

HG-312.3 

HG-312.6 

HG-312.7 

HG-320 

HG-321 
HG-326.1 

HG-326.2 
HG-340.1 
HG-340.2 
HG-340.3 

HG-343 

HG-345.1(a) 

HG-345.1(b) 

HG-350.1 

HG-350.2 

HG-350.3 

HG-350.4 
HG-402 

HG-530.1 

HG-530.2 
HG-530.3 
HG-530.4 
HG-530.5 
HG-530.6 
HG-530.7 
HG-703.1(a) 

HG-703.1(b) 

HG-703.2 
HG-725(a) 

HG-725(b) 



Setting 62 

Methods of Support 62 

Some Acceptable Types of Unstayed Flat Heads and Covers 8 

Spherically Dished Steel Plate Covers With Bolting Ranges 10 

Acceptable Type of Ring Reinforced Furnace 12 

Connection Between Plain and Corrugated Furnace 13 

Acceptable Type of Semicircular Furnace Reinforcement 14 

Chart Showing Limits of Sizes of Openings With Inherent 

Compensation in Cylindrical Shells 16 

Chart for Determining Values of F 17 

Some Representative Configurations Describing the Reinforcement 

Dimension, t e , and the Finished Opening Dimension, d 18 

Nomenclature and Formulas for Reinforced Openings 20 

Pitch of Staybolts Adjacent to Upper Corners of Fireboxes 23 

Acceptable Proportions for Ends of Through-Stays 23 

Examples of Acceptable Corner Welds for Pressures Not Over 

30 psi 23 

Details of Installation of Diagonal Stays 26 

Sketch Showing Application of HG-345.1 to the Staying of Boilers 28 

Sketch Showing Application of HG-345.1 to the Staying of Boilers 29 

Example of Tube Spacing With Pitch of Holes Equal in Every Row 30 

Example of Tube Spacing With Pitch of Holes Unequal in Every 

Second Row 30 

Example of Tube Spacing With Pitch of Holes Varying in Every 

Second and Third Row 30 

Example of Tube Spacing With Tube Holes on Diagonal Lines 31 

Official Symbol for Stamp to Denote The American Society of 

Mechanical Engineers' Standard 36 

Official Symbol for Stamp to Denote The American Society of 

Mechanical Engineers' Standard 46 

Steam and Water Boilers 46 

Boilers Suitable for Water Only 47 

Steam and Water Boilers 47 

Boilers Suitable for Water Only 48 

Steam and Water Boilers 48 

Boilers Suitable for Water Only 48 

Steam Boilers in Battery — Pumped Return — Acceptable Piping 

Installation 58 

Steam Boilers in Battery — Gravity Return — Acceptable Piping 

Installation 59 

Hot Water Boilers in Battery — Acceptable Piping Installation 60 

Spacing and Weld Details for Supporting Lugs in Pairs on 

Horizontal-Return Tubular Boiler 64 

Welded Bracket Connection for Horizontal-Return Tubular Boiler 64 



Tables 

HG-321 
HG-340 
HG-360 
HG-370 

HG-400.1 

HG-709.2 
HG-715 

PART HF 

Article 1 
HF-100 

Article 2 
HF-200 
HF-201 
HF-202 
HF-203 
HF-204 
HF-205 
HF-206 

HF-207 
HF-210 
Article 3 
HF-300 
HF-301 
HF-302 



Tables 

HF-300. 1 
HF-300.2 
HF-300.2M 
HF-301.1 
HF-301. 2 

PART HF — 
SUBPART HW 

Article 4 

HW-400 

HW-401 
Article 5 

HW-500 

HW-501 

HW-502 
Article 6 

HW-600 

HW-610 

HW-611 



Values of Spherical Radius Factor K\ 19 

Allowable Pitch of Stays, in. (mm) (Limited by HG-340.3) 25 

Permitted O-Ring Materials 31 

Minimum Thickness of Material for Threaded Connections to 

Boilers 32 

Minimum Pounds of Steam per Hour (kg/hr) per Square Foot (Meter) of 

Heating Surface 33 

Expansion Tank Capacities for Forced Hot Water Systems 61 

Size of Bottom Blowoff Piping, Valves, and Cocks 62 

REQUIREMENTS FOR BOILERS CONSTRUCTED OF 

WROUGHT MATERIALS 65 

General 65 

Scope 65 

Material Requirements 66 

General Material Requirements 66 

Plate 66 

Rods, Bars, and Shapes 66 

Prefabricated or Preformed Pressure Parts 66 

Pipe and Tubes 67 

Material Not Fully Identified 68 

Recertification of Material Produced to a Specification Not Permitted by 

This Section 68 

Austenitic Stainless Steel 68 

Maintaining Material Identification 69 

Design Stresses and Minimum Thicknesses 70 

Maximum Allowable Stress Values 70 

Minimum Thicknesses 70 

Basis for Establishing Stress Values in Tables HF-300. 1 and 

HF-300.2 70 

Maximum Allowable Stress Values for Ferrous Materials, ksi (MPa) 72 

Maximum Allowable Stress Values for Nonferrous Materials, ksi 77 

Maximum Allowable Stress Values for Nonferrous Materials, MPa 80 

Minimum Allowable Thickness of Ferrous Shell Plates 83 

Minimum Allowable Thickness of Nonferrous Shell Plates 83 

REQUIREMENTS FOR BOILERS FABRICATED BY 

WELDING 84 

General Requirements 84 

Scope 84 

Responsibility of Manufacturer or Contractor 84 

Material Requirements 85 

Permissible Materials 85 

Materials of Different Specifications 85 

Materials for Small Parts 85 

Welding Processes and Qualifications 86 

Welding Processes 86 

Welding Qualifications 86 

No Production Work Without Qualifications 86 



HW-612 
HW-613 
Article 7 
HW-700 
HW-701 
HW-702 
HW-703 
HW-710 
HW-711 
HW-712 
HW-713 
HW-715 
HW-720 
HW-730 
HW-731 
HW-740 

HW-745 
Article 8 

HW-800 

HW-801 

HW-810 

HW-812 

HW-813 

HW-820 

HW-830 

HW-840 
Article 9 

HW-900 

HW-910 

HW-911 

Figures 

HW-701. 1 
HW-701. 3 

HW-7 10.4(a) 

HW-7 10.4(b) 

HW-715.1 

HW-731 

HW-740 
HW-745 

Table 

HW-713 

PART HF — 
SUBPART HB 

Article 10 
HB-1000 
HB-1001 



Interchange of Qualifying Tests Among Manufacturers Prohibited 86 

Maintenance of Records of Qualifications and Identifying Marks 86 

Design of Weldments 87 

Design of Welded Joints 87 

General Requirements 87 

Joint Efficiencies 89 

Minimum Thickness of Welded Parts 89 

Welded Stays 89 

Heads or Tubesheets Attached by Welding 90 

Furnace Attachments 91 

Tubes Attached by Welding 91 

Head-to-Shell Attachments 91 

Openings in Welds 91 

Welded Connections 91 

Minimum Requirements for Attachment Welds 93 

Resistance Welding in Carbon Steel for Other Than Butt Welded 

Joints 96 

Resistance Welding of Hydraulically Formed Panels 98 

Fabrication Requirements 101 

Forming Plates 101 

Base Metal Preparation 101 

Assembly 101 

Alignment Tolerance 101 

Distortion 101 

Specific Welding Requirements 102 

Repair of Weld Defects 103 

Posthydrotest Welding of Nonpressure Parts to Pressure Parts 103 

Inspection 104 

Inspection During Fabrication 104 

Check of Welding Procedure Qualifications 104 

Check of Welder and Welding Operator Performance Qualifications 104 

Butt Welding of Plates of Unequal Thickness 87 

Some Forms of Attachments of Pressure Parts to Flat Plates to Form a 

Corner Joint (Tee Joint) 88 

Some Acceptable Types of Diagonal Stays for Installation by 

Welding 90 

Unacceptable Types of Diagonal Stays for Installation by Welding 90 

Heads Attached to Shells 92 

Some Acceptable Types of Welds for Fittings, Nozzles, and Other 

Connections to Shells, Drums, and Headers 94 

Three-Ply Joint Assemblies 97 

Two-Ply Joint Assemblies 99 

Firetube Extension Through Tubesheets for Welded Construction 92 

REQUIREMENTS FOR BOILERS FABRICATED BY 

BRAZING 105 

General Requirements 105 

Scope 105 

Responsibility of Manufacturer or Contractor 105 



IX 



Article 11 
HB-1100 
HB-1101 
HB-1102 
HB-1103 

Article 12 
HB-1200 
HB-1201 
HB-1202 

Article 13 
HB-1300 
HB-1301 
HB-1302 
HB-1303 
HB-1304 
HB-1305 
HB-1306 
HB-1307 

Article 14 
HB-1400 
HB-1401 
HB-1402 

Article 15 
HB-1500 
HB-1501 
HB-1502 
HB-1503 
HB-1510 



Material Requirements 106 

General 106 

Combinations of Dissimilar Materials 106 

Brazing Filler Metals 106 

Fluxes and Atmospheres 106 

Brazing Processes, Procedures, and Qualifications 107 

Brazing Processes 107 

Joint Brazing Procedures 107 

Brazing Qualifications and Records 107 

Design 108 

Strength of Brazed Joints 108 

Brazed Joint Efficiency Factors 108 

Minimum Thickness 108 

Permissible Service Temperature 108 

Application of Brazing Filler Metal 108 

Joint Clearance 108 

Openings 109 

Brazed Connections 109 

Fabrication Requirements 110 

Cleaning of Surfaces to Be Brazed 110 

Postbrazing Operations 1 10 

Repair of Defective Brazing 110 

Inspection and Stamping 11 

Inspection 11 

Inspection of Brazing Procedure 11 

Certification of Brazer and Brazing Operator 11 

Visual Examination 11 

Stamping 11 



Table 

HB-1305 



Recommended Joint Clearances at Brazing Temperature 109 



PART HC 

Article 1 
HC-100 

Article 2 
HC-200 
HC-201 
HC-202 
HC-203 
HC-204 
HC-205 
HC-206 
HC-207 
HC-208 
HC-209 
HC-210 
HC-211 
HC-212 
HC-213 
HC-214 
HC-215 



REQUIREMENTS FOR BOILERS CONSTRUCTED OF CAST 

IRON 112 

General 112 

Scope 112 

Material Requirements 113 

General Material Requirements 113 

Manufacture 113 

Chemical Composition 113 

Tensile Strength Classification 113 

Tension Test 113 

Test Bars 113 

Selection of Test Bar Size 113 

Molding and Pouring Test Bars 113 

Tensile Strength Test Procedure 113 

Transverse Test 114 

Transverse Test Procedure 115 

Number of Tests 115 

Retests 115 

Workmanship, Finish, and Repair 116 

Examinations and Tests 116 

Test Records 117 



Article 3 
HC-300 
HC-301 
HC-310 
HC-311 
HC-315 
HC-320 
HC-325 
HC-330 

Article 4 
HC-400 
HC-401 
HC-402 
HC-403 
HC-404 
HC-410 

Article 5 
HC-501 
HC-502 

HC-510 
HC-520 

Figures 

HC-205.1 
HC-206.1 
HC-311 

Tables 

HC-210 
HC-213 
HC-300 



PART HA 

Article 1 
HA- 100 

Article 2 
HA-200 
HA-201 
HA-202 
HA-203 

Article 3 
HA-300 
HA-301 
HA-302 
HA-303 
HA-304 
HA-305 

Article 4 
HA-400 
HA-401 
HA-402 



Design 118 

Maximum Allowable Stress Values 118 

Basis for Establishing Stress Values in Table HC-300 118 

Heads 118 

Spherically Shaped Covers 118 

Openings and Reinforcements 120 

Corners and Fillets 120 

Washout Openings 120 

Assembly Method 120 

Tests 121 

Tests to Establish Design Pressure 121 

General 121 

Bursting Test Procedure 121 

Witnessing, Recording, and Certifying Tests 122 

Rating of Production Boilers Based on Tests 122 

Hydrostatic Test 122 

Quality Control and Inspection 123 

General 123 

Outline of Features to Be Included in the Written Description 

of the Quality Control System 123 

Examination 124 

Certificates of Conformance 124 

Dimensions of Tensile Test Specimen 1 14 

Cast Test Bars 115 

Spherically Shaped Covers With Bolting Flanges 119 

Correction Factors for Transverse Test Bars 116 

Pipe Plug Size for Minimum Wall Thickness 117 

Maximum Allowable Stress Values in Tension for Cast Iron, ksi 

(MPa) 118 

REQUIREMENTS FOR BOILERS CONSTRUCTED OF CAST 

ALUMINUM 126 

General 126 

Scope 126 

Material Requirements 127 

General Material Requirements 127 

Workmanship, Finish, and Repair 127 

Examinations and Tests 127 

Test Records 128 

Design 129 

Maximum Allowable Stress Values 129 

Heads and Spherically Shaped Covers 129 

Openings and Reinforcements 129 

Corners and Fillets 129 

Washout Openings 129 

Assembly Method 129 

Tests 130 

Tests to Establish Design Pressure 130 

General 130 

Bursting Test Procedure 130 



HA-403 
HA-404 
HA-405 
HA-406 
Article 5 
HA-501 
HA-502 

HA-503 
HA-504 

PART HLW 

Introduction 

Article 1 
HLW- 100 
HLW-101 
HLW-102 
HLW-103 

Article 2 
HLW-200 
HLW-201 
HLW-202 
HLW-203 
HLW-204 
HLW-205 

Article 3 
HLW-300 
HLW-301 

HLW-302 
HLW-303 
HLW-305 
HLW-306 
HLW-307 
HLW-308 
HLW-309 
Article 4 
HLW-400 
HLW-401 
HLW-402 
HLW-411 
HLW-413 
HLW-415 
HLW-420 
HLW-430 
HLW-431 
HLW-432 
HLW-440 
HLW-450 
HLW-451 
HLW-452 
HLW-453 
HLW-454 
HLW-460 



Test Gages 130 

Witnessing, Recording, and Certifying Tests 130 

Rating of Production Boilers Based on Tests 131 

Hydrostatic Test 131 

Quality Control and Inspection 132 

General 132 

Outline of Features to Be Included in the Written Description of the 

Quality Control System 132 

Examination 133 

Certificates of Conformance 133 

REQUIREMENTS FOR POTABLE- WATER HEATERS 135 

135 

General 137 

Scope 137 

Service Restriction and Exception 137 

Permissible Stamping 137 

Units 137 

Material Requirements 139 

Lining 139 

Primary Pressure Parts Material 140 

Acceptance of Unidentified or Small Quantities of Material 140 

Miscellaneous Pressure Parts Material 141 

Flanges and Pipe Fittings 141 

Nonpressure Part Material 141 

Design 142 

Design 142 

Basis for Establishing Stress Values in Tables HLW-300 and 

HLW-301 142 

Minimum Thicknesses 142 

Shells Under Internal Pressure 142 

Blank Unstayed Dished Heads, Pressure on Concave Side 146 

Blank Unstayed Dished Heads, Pressure on Convex Side 147 

Tubes 147 

Openings 147 

Tubes Attached by Rolling 147 

Design of Weldments 148 

Design of Welded Joints 148 

General Requirements 148 

Joint Efficiencies 148 

Heads or Tubesheets Attached by Welding 149 

Tubes Attached by Welding 149 

Head-to-Shell Attachments 150 

Openings in Welds 150 

Welded Connections 154 

Minimum Requirements for Attachment Welds 154 

Brazed Connections for Copper Lined Vessels 158 

Welding Processes 158 

Welding Qualifications 158 

Production Work Qualifications 158 

Interchange of Qualifying Tests Among Manufacturers Prohibited 158 

Maintenance of Records of Qualifications and Identifying Marks 160 

Posthydrotest Welding of Nonpressure Parts to Pressure Parts 160 

Specific Welding Requirements 160 



Article 5 
HLW-500 

HLW-501 
HLW-502 
HLW-503 
HLW-504 
HLW-505 

Article 6 
HLW-600 
HLW-601 
HLW-602 

Article 7 
HLW-700 
HLW-701 
HLW-702 
HLW-703 
HLW-704 

Article 8 
HLW-800 
HLW-801 
HLW-805 
HLW-808 
HLW-809 
HLW-810 
HLW-820 

Figures 

HLW-401.1 

HLW-401.2 

HLW-411 

HLW-413 

HLW-415 

HLW-431.1 

HLW-431.5 

HLW-432.1 

HLW-602. 1 

HLW-602.2 
HLW-809. 1 

HLW-809.2 



Tables 

HLW-300 

HLW-301 
HLW-809. 1 



Tests 162 

Tests to Establish Maximum Allowable Working Pressure and 

Production Line Tests 162 

General 162 

Proof Test 162 

Testing of Parts 163 

Witnessing, Recording, and Certifying Tests 163 

Hydrostatic Test 163 

Inspection and Stamping 164 

Inspection and Certification 164 

Manufacturer's Data and Partial Data Reports 164 

Stamping of Water Heaters and Storage Tanks 165 

Controls 167 

Controls 167 

Temperature Control 167 

Limit Controls 167 

Controls and Heat Generating Apparatus 167 

Electrical Wiring 167 

Installation Requirements 168 

Safety Relief Valves 168 

Mounting Safety Relief Valves 168 

Water Supply 169 

Storage Tanks 169 

Provisions for Thermal Expansion in Hot Water Systems 169 

Bottom Drain Valve 169 

Thermometer 170 

Butt Welding of Plates of Unequal Thickness 148 

Typical Corner Joints 149 

Typical Water Heater Welded Joints 150 

Tubes Attached by Welding 152 

Heads Attached to Shells 153 

Some Acceptable Types of Welds for Fittings, Nozzles, and Other 

Connections to Shells and Head 155 

Some Acceptable Types of Welds for Fittings, Nozzles, and Other 

Connections to Shells and Head 156 

Some Acceptable Types of Brazed Fittings, Nozzles, and Other 

Connections to Copper-Lined Shells and Heads 159 

Official Symbol to Denote The American Society of Mechanical 

Engineers' Standard 165 

Form of Stamping on Completed Water Heaters 165 

A Typical Acceptable Piping Installation for Storage Water Heaters in 

Battery 170 

A Typical Acceptable Piping Installation for Flow Through Water 

Heater With Provisions for Piping Expansion 171 

Maximum Allowable Stress Values in Tension for Lined Materials, ksi 

(MPa) 143 

Maximum Allowable Stress Values for Materials in Tension for 

Unlined Water Heaters, ksi (MPa) 145 

Expansion Tank Capacities for a Water Heater 169 



Mandatory Appendices 

1 Submittal of Technical Inquiries to the Boiler and Pressure Vessel 

Committee 173 

2 Codes, Standards, and Specifications Referenced in Text 175 

3 Adhesive Attachment of Nameplates to Casing 176 

5 Vacuum Boilers 177 

6 Standard Units for Use in Equations 179 

Nomandatory Appendices 

B Method of Checking Safety Valve and Safety Relief Valve Capacity 

by Measuring Maximum Amount of Fuel That Can Be 
Burned 180 

C Examples of Method of Calculating a Welded Ring Reinforced 

Furnace 181 

D Examples of Methods of Computation of Openings in Boiler 

Shells 183 

E Terminology 186 

F Quality Control System 190 

H List of Abbreviations and Addresses 192 

I Specifications for Test Method for Water Absorption of Plastics 193 

K Guide to Information Appearing on Certificate of Authorization 196 

L Guide to Manufacturer's Data Report Forms 199 

M Guidance for the Use of U.S. Customary and SI Units in the 

ASME Boiler and Pressure Vessel Code 223 

N Guide to Manufacturer's Certificate of Conformance for Pressure 

Relief Valves 226 

Index 229 



FOREWORD 



The American Society of Mechanical Engineers set up a 
committee in 191 1 for the purpose of formulating standard 
rules for the construction of steam boilers and other pres- 
sure vessels. This committee is now called the Boiler and 
Pressure Vessel Committee. 

The Committee's function is to establish rules of safety, 
relating only to pressure integrity, governing the construc- 
tion 1 of boilers, pressure vessels, transport tanks and 
nuclear components, and inservice inspection for pressure 
integrity of nuclear components and transport tanks, and 
to interpret these rules when questions arise regarding their 
intent. This code does not address other safety issues relat- 
ing to the construction of boilers, pressure vessels, transport 
tanks and nuclear components, and the inservice inspection 
of nuclear components and transport tanks. The user of 
the Code should refer to other pertinent codes, standards, 
laws, regulations, or other relevant documents. With few 
exceptions, the rules do not, of practical necessity, reflect 
the likelihood and consequences of deterioration in service 
related to specific service fluids or external operating envi- 
ronments. Recognizing this, the Committee has approved 
a wide variety of construction rules in this Section to allow 
the user or his designee to select those that will provide a 
pressure vessel having a margin for deterioration in service 
so as to give a reasonably long, safe period of usefulness. 
Accordingly, it is not intended that this Section be used 
as a design handbook; rather, engineering judgment must 
be employed in the selection of those sets of Code rules 
suitable to any specific service or need. 

This Code contains mandatory requirements, specific 
prohibitions, and nonmandatory guidance for construction 
activities. The Code does not address all aspects of these 
activities and those aspects that are not specifically 
addressed should not be considered prohibited. The Code 
is not a handbook and cannot replace education, experience, 
and the use of engineering judgment. The phrase engi- 
neering judgment refers to technical judgments made by 
knowledgeable designers experienced in the application of 
the Code. Engineering judgments must be consistent with 
Code philosophy and such judgments must never be used 
to overrule mandatory requirements or specific prohibitions 
of the Code. 



1 Construction, as used in this Foreword, is an all-inclusive term com- 
prising materials, design, fabrication, examination, inspection, testing, 
certification, and pressure relief. 



The Committee recognizes that tools and techniques 
used for design and analysis change as technology prog- 
resses and expects engineers to use good judgment in the 
application of these tools. The designer is responsible for 
complying with Code rules and demonstrating compliance 
with Code equations when such equations are mandatory. 
The Code neither requires nor prohibits the use of comput- 
ers for the design or analysis of components constructed 
to the requirements of the Code. However, designers and 
engineers using computer programs for design or analysis 
are cautioned that they are responsible for all technical 
assumptions inherent in the programs they use and they 
are responsible for the application of these programs to 
their design. 

The Code does not fully address tolerances. When 
dimensions, sizes, or other parameters are not specified 
with tolerances, the values of these parameters are consid- 
ered nominal and allowable tolerances or local variances 
may be considered acceptable when based on engineering 
judgment and standard practices as determined by the 
designer. 

The Boiler and Pressure Vessel Committee deals with 
the care and inspection of boilers and pressure vessels in 
service only to the extent of providing suggested rules of 
good practice as an aid to owners and their inspectors. 

The rules established by the Committee are not to be 
interpreted as approving, recommending, or endorsing any 
proprietary or specific design or as limiting in any way the 
manufacturer's freedom to choose any method of design 
or any form of construction that conforms to the Code rules. 

The Boiler and Pressure Vessel Committee meets regu- 
larly to consider revisions of the rules, new rules as dictated 
by technological development, Code Cases, and requests 
for interpretations. Only the Boiler and Pressure Vessel 
Committee has the authority to provide official interpreta- 
tions of this Code. Requests for revisions, new rules, Code 
Cases, or interpretations shall be addressed to the Secretary 
in writing and shall give full particulars in order to receive 
consideration and action (see Mandatory Appendix cov- 
ering preparation of technical inquiries). Proposed revi- 
sions to the Code resulting from inquiries will be presented 
to the Main Committee for appropriate action. The action 
of the Main Committee becomes effective only after con- 
firmation by letter ballot of the Committee and approval 
by ASME. 



Proposed revisions to the Code approved by the Commit- 
tee are submitted to the American National Standards Insti- 
tute and published at http://cstools.asme.org/csconnect/ 
public/index.cfm?PublicReview = Revisions to invite com- 
ments from all interested persons. After the allotted time 
for public review and final approval by ASME, revisions 
are published annually in Addenda to the Code. 

Code Cases may be used in the construction of compo- 
nents to be stamped with the ASME Code symbol begin- 
ning with the date of their approval by ASME. 

After Code revisions are approved by ASME, they may 
be used beginning with the date of issuance shown on 
the Addenda. Revisions, except for revisions to material 
specifications in Section II, Parts A and B, become manda- 
tory six months after such date of issuance, except for 
boilers or pressure vessels contracted for prior to the end 
of the six-month period. Revisions to material specifica- 
tions are originated by the American Society for Testing 
and Materials (ASTM) and other recognized national or 
international organizations, and are usually adopted by 
ASME. However, those revisions may or may not have 
any effect on the suitability of material, produced to earlier 
editions of specifications, for use in ASME construction. 
ASME material specifications approved for use in each 
construction Code are listed in the Guidelines for Accept- 
able ASTM Editions in Section II, Parts A and B. These 
Guidelines list, for each specification, the latest edition 
adopted by ASME, and earlier and later editions considered 
by ASME to be identical for ASME construction. 

The Boiler and Pressure Vessel Committee in the formu- 
lation of its rules and in the establishment of maximum 
design and operating pressures considers materials, con- 
struction, methods of fabrication, inspection, and safety 
devices. 

The Code Committee does not rule on whether a compo- 
nent shall or shall not be constructed to the provisions of 
the Code. The Scope of each Section has been established 
to identify the components and parameters considered by 
the Committee in formulating the Code rules. 

Questions or issues regarding compliance of a specific 
component with the Code rules are to be directed to the 
ASME Certificate Holder (Manufacturer). Inquiries con- 
cerning the interpretation of the Code are to be directed 
to the ASME Boiler and Pressure Vessel Committee. 



ASME is to be notified should questions arise concerning 
improper use of an ASME Code symbol. 

The specifications for materials given in Section II are 
identical with or similar to those of specifications published 
by ASTM, AWS, and other recognized national or interna- 
tional organizations. When reference is made in an ASME 
material specification to a non-ASME specification for 
which a companion ASME specification exists, the refer- 
ence shall be interpreted as applying to the ASME material 
specification. Not all materials included in the material 
specifications in Section II have been adopted for Code 
use. Usage is limited to those materials and grades adopted 
by at least one of the other Sections of the Code for applica- 
tion under rules of that Section. All materials allowed by 
these various Sections and used for construction within the 
scope of their rules shall be furnished in accordance with 
material specifications contained in Section II or referenced 
in the Guidelines for Acceptable ASTM Editions in Section 
II, Parts A and B, except where otherwise provided in Code 
Cases or in the applicable Section of the Code. Materials 
covered by these specifications are acceptable for use in 
items covered by the Code Sections only to the degree 
indicated in the applicable Section. Materials for Code use 
should preferably be ordered, produced, and documented 
on this basis; Guideline for Acceptable ASTM Editions in 
Section II, Part A and Guideline for Acceptable ASTM 
Editions in Section II, Part B list editions of ASME and 
year dates of specifications that meet ASME requirements 
and that may be used in Code construction. Material pro- 
duced to an acceptable specification with requirements dif- 
ferent from the requirements of the corresponding 
specifications listed in the Guideline for Acceptable ASTM 
Editions in Part A or Part B may also be used in accordance 
with the above, provided the material manufacturer or ves- 
sel manufacturer certifies with evidence acceptable to the 
Authorized Inspector that the corresponding requirements 
of specifications listed in the Guideline for Acceptable 
ASTM Editions in Part A or Part B have been met. Material 
produced to an acceptable material specification is not 
limited as to country of origin. 

When required by context in this Section, the singular 
shall be interpreted as the plural, and vice-versa; and the 
feminine, masculine, or neuter gender shall be treated as 
such other gender as appropriate. 



STATEMENT OF POLICY 

ON THE USE OF CODE SYMBOLS AND 

CODE AUTHORIZATION IN ADVERTISING 



ASME has established procedures to authorize qualified 
organizations to perform various activities in accordance 
with the requirements of the ASME Boiler and Pressure 
Vessel Code. It is the aim of the Society to provide recogni- 
tion of organizations so authorized. An organization hold- 
ing authorization to perform various activities in 
accordance with the requirements of the Code may state 
this capability in its advertising literature. 

Organizations that are authorized to use Code Symbols 
for marking items or constructions that have been con- 
structed and inspected in compliance with the ASME Boiler 
and Pressure Vessel Code are issued Certificates of Autho- 
rization. It is the aim of the Society to maintain the standing 
of the Code Symbols for the benefit of the users, the 
enforcement jurisdictions, and the holders of the symbols 
who comply with all requirements. 

Based on these objectives, the following policy has been 
established on the usage in advertising of facsimiles of the 
symbols, Certificates of Authorization, and reference to 
Code construction. The American Society of Mechanical 
Engineers does not "approve," "certify," "rate," or 



"endorse" any item, construction, or activity and there shall 
be no statements or implications that might so indicate. An 
organization holding a Code Symbol and/or a Certificate of 
Authorization may state in advertising literature that items, 
constructions, or activities "are built (produced or per- 
formed) or activities conducted in accordance with the 
requirements of the ASME Boiler and Pressure Vessel 
Code," or "meet the requirements of the ASME Boiler and 
Pressure Vessel Code." 

The ASME Symbol shall be used only for stamping and 
nameplates as specifically provided in the Code. However, 
facsimiles may be used for the purpose of fostering the 
use of such construction. Such usage may be by an associa- 
tion or a society, or by a holder of a Code Symbol who 
may also use the facsimile in advertising to show that 
clearly specified items will carry the symbol. General usage 
is permitted only when all of a manufacturer's items are 
constructed under the rules. 

The ASME logo, which is the cloverleaf with the letters 
ASME within, shall not be used by any organization other 
than ASME. 



STATEMENT OF POLICY 

ON THE USE OF ASME MARKING 

TO D3ENTIFY MANUFACTURED ITEMS 



The ASME Boiler and Pressure Vessel Code provides 
rules for the construction of boilers, pressure vessels, and 
nuclear components. This includes requirements for mate- 
rials, design, fabrication, examination, inspection, and 
stamping. Items constructed in accordance with all of the 
applicable rules of the Code are identified with the official 
Code Symbol Stamp described in the governing Section 
of the Code. 

Markings such as "ASME," "ASME Standard," or any 
other marking including "ASME" or the various Code 



Symbols shall not be used on any item that is not con- 
structed in accordance with all of the applicable require- 
ments of the Code. 

Items shall not be described on ASME Data Report 
Forms nor on similar forms referring to ASME that tend 
to imply that all Code requirements have been met when, 
in fact, they have not been. Data Report Forms covering 
items not fully complying with ASME requirements should 
not refer to ASME or they should clearly identify all excep- 
tions to the ASME requirements. 



xvn 



PERSONNEL 

ASME Boiler and Pressure Vessel Committee 

Subcommittees, Subgroups, and Working Groups 



As of January 1, 2007 



MAIN COMMITTEE 



HONORS AND AWARDS COMMITTEE 



G. G. Karcher, Chair 

). G. Feldstein, Vice Chair 

J. S. Brzuszkiewicz, Secretary 

R. W. Barnes 

R. J. Basile 

J. E. Batey 

D. L. Berger 

M. N. Bressler 

D. A. Canonico 

R. P. Deubler 

D. A. Douin 

R. E. Gimple 

M. Gold 

T. E. Hansen 

C. L. Hoffmann 

D. F. Landers 
W. M. Lundy 
J. R. MacKay 



U. R. Miller 
P. A. Molvie 

C. C. Neely 
W. E. Norris 
G. C. Park 
T. P. Pastor 
M. D. Rana 
B. W. Roberts 
F. J. Schaaf, Jr. 
A. Selz 

R. W. Swayne 

D. E. Tanner 
S. V. Voorhees 

F. B. Kovacs, Alternate 
R. A. Moen, Honorary 

Member 
T. Tahara, Delegate 



J. R. MacKay, Chair 
M. Gold, Vice Chair 
G. Moino, Secretary 
R. J. Basile 
J. E. Batey 
D. L. Berger 
J. G. Feldstein 
F. E. Gregor 



W. L. Haag, Jr. 
S. F. Harrison, Jr. 
R. M. Jessee 
W. C. Larochelle 
T. P. Pastor 
A. Selz 
R. R. Stevenson 



MARINE CONFERENCE GROUP 



H. N. Patel, Chair 
L W. Douthwaite 



R. J. Petow 



CONFERENCE COMMITTEE 



EXECUTIVE COMMITTEE (MAIN COMMITTEE) 



J. G. Feldstein, Chair 

G. G. Karcher, Vice Chair 

J. S. Brzuszkiewicz, Secretary 

R. W. Barnes 

D. L Berger 

M. Gold 

G. C. Park 



T. P. Pastor 

A. Selz 

D. E. Tanner 

D. A. Canonico, Ex-Officio 

Member 
M. Kotb, Ex-Officio Member 



HONORARY MEMBERS (MAIN COMMITTEE) 



F. P. Barton 
R. D. Bonner 
R. J. Bosnak 
R. J. Cepluch 
L. J. Chockie 
T. M. Cullen 
W. D. Doty 
J. R. Farr 

G. E. Feigel 
R. C. Griffin 
O. F. Hedden 
E. J. Hemzy 



M. H. Jawad 
A. J. Justin 
E. L. Kemmler 
W. G. Knecht 
J. LeCoff 
T. G. McCarty 
G. C. Millman 
R. F. Reedy 
W. E. Somers 
K. K. Tarn 
L. P. Zick, Jr. 



D. A. Douin — Illinois (Chair) 
R. D. Reetz — North Dakota 
(Vice Chair) 

D. E. Tanner — Ohio 
(Secretary) 

R. J. Aben, Jr. — Michigan 
J. S. Aclaro — California 

A. E. Adkins — West Virginia 
J. T. Amato — Minnesota 

E. A. Anderson — Illinois 

F. R. Andrus — Oregon 

B. P. Anthony — Rhode Island 
R. D. Austin — Colorado 

E. W. Bachellier — Nunavut, 
Canada 

M. M. Barber — Michigan 
R. W. Bartlett — Arizona 

F. P. Barton — Virginia 
M. Bishop — British 

Columbia, Canada 
W. K. Brigham — New 

Hampshire 
D. E. Burns — Nebraska 
J. H. Burpee — Maine 

C. J. Castle — Nova Scotia, 
Canada 

P. A. Conklin — New York 



D. C. Cook — California 
R. A. Coomes — Kentucky 

D. Eastman — Newfoundland 
and Labrador, Canada 

G. L. Ebeyer — Louisiana 

E. Everett — Georgia 

J. M. Given, Jr. — North 

Carolina 
P. Hackford — Utah 
R. J. Handy — Kentucky 
J. B. Harlan — Delaware 
M. L. Holloway — Oklahoma 
K. Hynes — Prince Edward 

Island, Canada 
D. T. Jagger — Ohio 
D. J. Jenkins — Kansas 
S. Katz — British Columbia, 

Canada 
M. Kotb — Quebec, Canada 
K. T. Lau — Alberta, Canada 
M. A. Malek — Florida 
G. F. Mankel — Nevada 
R. D. Marvin II — Washington 
I. W. Mault — Manitoba, 

Canada 
H. T. McEwen — Mississippi 



xix 



CONFERENCE COMMITTEE (CONT'D) 



Subgroup on Design (SC I) 



R. D. Mile — Ontario, Canada 
M. F. Mooney — 

Massachusetts 
G. R. Myrick — Arkansas 
Y. Nagpaul — Hawaii 
W. R. Owens — Louisiana 
T. M. Parks — Texas 
R. P. Pate — Alabama 
J. D. Payton — Pennsylvania 
M. R. Peterson — Alaska 
H. D. Pfaff — South Dakota 
J. L. Pratt — Missouri 
D. C. Price — Yukon 

Territory, Canada 



R. S. Pucek — Wisconsin 

D. E. Ross — New Brunswick, 
Canada 

N. Surtees — Saskatchewan, 

Canada 
M. R. Toth — Tennessee 
M. J. Verhagen — Wisconsin 
M. Washington — New Jersey 
R. B. West — Iowa 
M. J. Wheel — Vermont 
D.J. Willis — Indiana 

E. Zarate — Arizona 



BPV PROJECT TEAM ON HYDROGEN TANKS 



M. D. Rana, Chair 

G. M. Eisenberg, Secretary 

F. L. Brown 

D. A. Canonico 
D. C. Cook 
J. W. Felbaum 
T. Joseph 
J. M. Lacy 
N. L. Newhouse 

G. B. Rawls, Jr. 
J. R. Sims, Jr. 
N. Sirosh 

J. H. Smith 
S. Staniszewski 
T. Tahara 

D. W. Treadwell 

E. Upitis 

C. T. L. Webster 
H. Barthelemy, Corresponding 
Member 



R. C. Biel, Corresponding 

Member 
J. Cameron, Corresponding 

Member 
M. Duncan, Corresponding 

Member 
D. R. Frikken, Corresponding 

Member 
L. E. Hayden, Jr., 

Corresponding Member 
K. T. Lau, Corresponding 

Member 
K. Oyamada, Corresponding 

Member 
C. H. Rivkin, Corresponding 

Member 
C. San Marchi, Corresponding 

Member 
B. Somerday, Corresponding 

Member 



INTERNATIONAL INTEREST REVIEW GROUP 



V. Felix 
S. H. Leong 
W. Lin 
C. Minu 



Y. Park 

P. Williamson 

Y. Kim, Delegate 



P. A. Molvie, Chair 

G. L. Hiler, Secretary 

M. L. Coats 

J. D. Fishburn 

J. P. Glaspie 

C. F. Jeerings 

G. B. Komora 



J. P. Libbrecht 
J. C. Light 
B. W. Moore 
R. D. Schueler, Jr. 
J. L. Seigle 
J. P. Swezy, Jr. 
S. V. Torkildson 



Subgroup on Fabrication and Examination (SC I) 



J. T. Pillow, Chair 
J. L. Arnold 
D. L. Berger 
S. W. Cameron 
G. W. Galanes 
J. Hainsworth 



T. E. Hansen 
T. C. McGough 
R. E. McLaughlin 
Y. Oishi 
R. V. Wielgoszinski 



Subgroup on General Requirements (SC I) 



R. E. McLaughlin, Chair 

J. Hainsworth, Secretary 

G. Cook 

P. D. Edwards 

T. E. Hansen 

W. L. Lowry 

F. Massi 



T. C. McGough 
J. T. Pillow 
D. Tompkins 
S. V. Torkildson 
R. V. Wielgoszinski 
D.J.Willis 



Subgroup on Materials (SC I) 



B. W. Roberts, Chair 
J. S. Hunter, Secretary 
D. A. Canonico 
K. K. Coleman 
G. W. Galanes 
K. L. Hayes 



J. F. Henry 
J. P. Libbrecht 
J. R. MacKay 
F. Masuyama 
J. M. Tanzosh 



Subgroup on Piping (SC I) 



SUBCOMMITTEE ON POWER BOILERS (SC I) 



D. L. Berger, Chair 

B. W. Roberts, Vice Chair 
U. D'Urso, Secretary 

D. A. Canonico 
K. K. Coleman 
P. D. Edwards 
J. G. Feldstein 
J. Hainsworth 
T. E. Hansen 
J. S. Hunter 

C. F. Jeerings 
J. P. Libbrecht 



D. N. French 
W. E. Somers 



W. L. Lowry 
J. R. MacKay 
T. C. McGough 
R. E. McLaughlin 
P. A. Molvie 
Y. Oishi 
J. T. Pillow 
R. D. Schueler, Jr. 
J. P. Swezy, Jr. 
J. M. Tanzosh 
R. V. Wielgoszinski 
D.J. Willis 



Honorary Members (SC I) 

R. L. Williams 



T. E. Hansen, Chair 
D. L. Berger 
P. D. Edwards 
G. W. Galanes 
W. L. Lowry 



F. Massi 

T. C. McGough 

D. Tompkins 

E. A. Whittle 



Heat Recovery Steam Generators Task Group (SC I) 



T. E. Hansen, Chair 

E. M. Ortman, Secretary 

R. W. Anderson 

J. P. Bell 

L. R. Douglas 

J. D. Fishburn 

G. B. Komora 

J. P. Libbrecht 

D. L. Marriott 



B. W. Moore 

A. L. Plumley 

R. D. Schueler, Jr. 
J. C. Steverman, Jr. 
S. R. Timko 

D. Tompkins 

S. V. Torkildson 

B. C. Turczynski 

E. A. Turhan 



SUBCOMMITTEE ON MATERIALS (SC II) 



Subgroup on Strength, Ferrous Alloys (SC II) 



J. F. Henry, Chair 

M. Gold, Vice Chair 

N. Lobo, Secretary 

F.Abe 

D. C. Agarwal 

W. R. Apblett, Jr. 

A. Appleton 

M. N. Bressler 

H. D. Bushfield 

J. Cameron 

D. A. Canonico 

A. Chaudouet 

P. Faliouey 

D. W. Gandy 

M. H. Gilkey 

J. F. Grubb 



C. L. Hoffmann 
P. A. Larkin 

F. Masuyama 
R. K. Nanstad 
M. L. Nayyar 
E. G. Nisbett 

D. W. Rahoi 
B. W. Roberts 

E. Shapiro 

R. C. Sutherlin 

R. W. Swindeman 

J. M. Tanzosh 

B. E. Thurgood 

R. A. Moen, Honorary 

Member 
D. Kwon, Delegate 



Honorary Members (SC II) 

A. P. Ahrendt J. J. Heger 

T. M. Cullen G. C. Hsu 

R. Dirscherl R. A. Moen 

W. D. Doty C. E. Spaeder, Jr. 

W. D. Edsall A. W. Zeuthen 

Subgroup on External Pressure (SC II & SC-D) 



R. W. Mikitka, Chair 

J. A. A. Morrow, Secretary 

L. F. Campbell 

D. S. Griffin 

J. F. Grubb 



M. Katcher 

D. L. Kurle 

E. Michalopoulos 
D. Nadel 

C. H. Sturgeon 



Subgroup on Ferrous Specifications (SC II) 



E. G. Nisbett, Chair 

A. Appleton, Vice Chair 
R. M. Davison 

B. M. Dingman 
M. J. Dosdourian 
T. Graham 

J. F. Grubb 
K. M. Hottle 
D. S. Janikowski 



D. C. Krouse 
L. J. Lavezzi 
W. C. Mack 

J. K. Mahaney 
A. S. Melilli 
K. E. Orie 

E. Upitis 

R. Zawierucha 
A. W. Zeuthen 



Subgroup on International Material Specifications (SC II) 



W. M. Lundy, Chair 

A. Chaudouet, Vice Chair 

J. P. Glaspie, Secretary 

D. C. Agarwal 

H. D. Bushfield 

D. A. Canonico 

P. Faliouey 

A. F. Garbolevsky 



D. O. Henry 
M. Higuchi 
H. Lorenz 

A. R. Nywening 
R. D. Schueler, Jr. 

E. A. Steen 
E. Upitis 

D. Kwon, Delegate 



Subgroup on Nonferrous Alloys (SC II) 



D. W. Rahoi, Chair 
M. Katcher, Secretary 

D. C. Agarwal 
W. R. Apblett, Jr. 
H. D. Bushfield 
L. G. Coffee 

M. H. Gilkey 
J. F. Grubb 

E. L. Hibner 
G. C. Hsu 



A. G. Kireta, Jr. 
J. Kissel I 
P. A. Larkin 
H. Matsuo 
J. A. McMaster 

D. T. Peters 

E. Shapiro 

R. C. Sutherlin 
R. Zawierucha 



C. L. Hoffmann, Chair 

J. M. Tanzosh, Secretary 

F. Abe 

W. R. Apblett, Jr. 

D. A. Canonico 
K. K. Coleman 
P. Faliouey 

M. Gold 
J. F. Henry 

E. L. Hibner 



F. Masuyama 
H. Matsuo 
H. Murakami 
D. W. Rahoi 
B. W. Roberts 
M. S. Shelton 
R. W. Swindeman 
B. E. Thurgood 
T. P. Vassallo, Jr. 



Subgroup on Physical Properties (SC II) 



J. F. Grubb, Chair 
D. C. Agarwal 
H. D. Bushfield 



P. Faliouey 
E. Shapiro 



Subgroup on Strength of Weldments (SC II & SC IX) 



J. M. Tanzosh, Chair 

W. F. Newell, Jr., Secretary 

K. K. Coleman 

P. D. Flenner 

D. W. Gandy 

K. L. Hayes 



J. F. Henry 
D. W. Rahoi 
B. W. Roberts 
W. J. Sperko 
B. E. Thurgood 



Subgroup on Toughness (SC II & SC VIII) 



W. S. Jacobs, Chair 
J. L. Arnold 
R. J. Basile 
J. Cameron 
H. E. Gordon 
D. C. Lamb 



K. Mokhtarian 

C. C. Neely 
T. T. Phillips 
M. D. Rana 

D. A. Swanson 

E. Upitis 



Special Working Group on Nonmetallic Materials (SC II) 



C. W. Rowley, Chair 
F. L. Brown 
S. R. Frost 
P. S. Hill 



M. R. Kessler 
R. H. Walker 
J. W. Wegner 
F. Worth 



SUBCOMMITTEE ON NUCLEAR POWER (SC III) 



R. W. Barnes, Chair 
R. M. Jessee, Vice Chair 
C. A. Sanna, Secretary 
W. H. Borter 
M. N. Bressler 
J. R. Cole 
R. E. Cornman, Jr. 
R. P. Deubler 

B. A. Erler 
G. M. Foster 
R. S. Hill III 

C. L. Hoffmann 
C. C. Kim 



V. Kostarev 

D. F. Landers 

W. C. LaRochelle 
K. A. Manoly 

E. A. Mayhew 
W. N. McLean 
D. K. Morton 
O. O. Oyamada 
R. F. Reedy 

B. B. Scott 
J. D. Stevenson 
K. R. Wichman 
Y. H. Choi, Delegate 



Honorary Members (SC III) 

R. J. Bosnak F. R. Drahos 

E. B. Branch R. A. Moen 

W. D. Doty C. J. Pieper 



Subgroup on Containment Systems for Spent Fuel 
and High-Level Waste Transport Packagings (SC III) 



Working Group on Piping (SG-D) (SC III) 



G. M. Foster, Chair 

G. J. Solovey, Vice Chair 

D. K. Morton, Secretary 
W. H. Borter 

G. R. Cannell 

E. L. Farrow 
R. S. Hill III 
D. W. Lewis 
C. G. May 

P. E. McConnell 
I. D. Mclnnes 



A. B. Meichler 
R. E. Nickell 
E. L. Pleins 
T. Saegusa 
H. P. Shrivastava 
N. M. Simpson 
R. H. Smith 
J. D. Stevenson 
C. J. Temus 
P. Turula 
A. D. Watkins 



Subgroup on Design (SC III) 



R. P. Deubler, Chair 
R. S. Hill III, Vice Chair 
A. N. Nguyen, Secretary 
T. M. Adams 
M. N. Bressler 

C. W. Bruny 

D. L. Caldwell 
J. R: Cole 

R. E. Cornman, Jr. 
A. A. Dermenjian 
P. Hirschberg 
R. I. Jetter 
R. B. Keating 
J. F. Kielb 
H. Kobayashi 



D. F. Landers 
K. A. Manoly 
R. J. Masterson 
W. N. McLean 
J. C. Minichiello 
M. Morishita 

F. F. Naguib 
T. Nakamura 
W. Z. Novak 

E. L. Pleins 
I. Saito 

G. C. Slagis 

J. D. Stevenson 
J. P. Tucker 
K. R. Wichman 



Working Group on Supports (SG-D) (SC III) 



R. J. Masterson, Chair 
F. J. Birch, Secretary 
U. S. Bandyopadhyay 
R. P. Deubler 
W. P. Golini 
A. N. Nguyen 



I. Saito 
J. R. Stinson 
T. G. Terryah 
D. V. Walshe 
C.-l. Wu 



Working Group on Core Support Structures (SG-D) (SC III) 



J. F. Kielb, Chair 
J. T. Land 



J. F. Mullooly 



Working Group on Design Methodology (SG-D) 



R. B. Keating, Chair 

P. L. Anderson, Secretary 

T. M. Adams 

M. K. Au-Yang 

R. D. Blevins 

D. L. Caldwell 

M. Hartzman 

H. Kobayashi 



D. F. Landers 
W. S. Lapay 
H. Lockert 
J. F. McCabe 
P. R. Olson 
J. D. Stevenson 
J. Yang 



Working Group on Design of Division 3 Containments 
(SG-D) (SC III) 



E. L. Pleins, Chair 
T. M. Adams 
G. Bjorkman 
D. W. Lewis 
I. D. Mclnnes 
]. C. Minichiello 



D. K. Morton 
R. E. Nickell 
H. P. Shrivastava 
C. J. Temus 
P. Turula 



P. Hirschberg, Chair 

R. C. Fung, 5ecrefary 

T. M. Adams 

C. Basavaraju 

J. Catalano 

J. R. Cole 

R. J. Gurdal 

R. W. Haupt 

J. Kawahata 

R. B. Keating 

V. Kostarev 



D. F. Landers 
J. F. McCabe 

J. C. Minichiello 
A. N. Nguyen 
O. O. Oyamada 
R. D. Patel 

E. C. Rodabaugh 
M. S. Sills 

G. C. Slagis 
E. A. Wais 
C.-l. Wu 



Working Group on Probabilistic Methods in Design 
(SG-D) (SC III) 



R. S. Hill III, Chair 
T. M. Adams 
T. Asayama 
B. M. Ayyub 
T. A. Bacon 
A. A. Dermenjian 
M. R. Graybeal 

D. O. Henry 

E. V. Imbro 



S. D. Kulat 
A. McNeill III 
P. J. O'Regan 
N. A. Palm 
I. Saito 

M. E. Schmidt 
J. P. Tucker 
R. M. Wilson 



Working Group on Pumps (SG-D) (SC III) 



R. E. Cornman, Jr., Chair 
M. D. Eftychiou 
A. A. Fraser 
M. Higuchi 
G. R. Jones 



J. W. Leavitt 
J. E. Livingston 
J. R. Rajan 
A. G. Washburn 



Working Group on Valves (SG-D) (SC III) 



J. P. Tucker, Chair 
R. R. Brodin 
G. A. Jolly 
W. N. McLean 
T. A. McMahon 



J. D. Page 
S. N. Shields 
H. R. Sonderegger 
J. C. Tsacoyeanes 
R. G. Visalli 



Working Group on Vessels (SG-D) (SC III) 



F. F. Naguib, Chair 

G. K. Miller, Secretary 
C. W. Bruny 

G. D. Cooper 
M. Hartzman 
W. J. Heilker 



A. Kalnins 
R. B. Keating 
K. Matsunaga 
D. E. Matthews 
M. Nakahira 
R. M. Wilson 



Special Working Group on Environmental Effects (SG-D) (SC III) 



W. Z. Novak, Chair 
R. S. Hill III 
C. L. Hoffmann 



S. Yukawa 

Y. H. Choi, Delegate 



Subgroup on General Requirements (SC III & SC 3C) 



W. C. LaRochelle, Chair 

C. A. Lizotte, Secretary 

A. Appleton 

J. R. Berry 

W. P. Golini 

E. A. Mayhew 

R. P. Mclntyre 



R. D. Mile 
M. R. Minick 
B. B. Scott 
H. K. Sharma 
W. K. Sowder 
D. M. Vickery 
D. V. Walshe 



Subgroup on Materials, Fabrication, and Examination (SC III) 



SUBCOMMITTEE ON HEATING BOILERS (SC IV) 



C. L. Hoffmann, Chair 
G. P. Milley, Secretary 
W. H. Borter 

D. M. Doyle 
G. M. Foster 
G. B. Georgiev 
R. M. Jessee 

C. C. Kim 
M. Lau 



H. Murakami 
M. Nakahira 
C. J. Pieper 
N. M. Simpson 
W. J. Sperko 
J. R. Stinson 
K. B. Stuckey 
A. D. Watkins 
S. Yukawa 



Subgroup on Pressure Relief (SC III) 



S. F. Harrison, Jr., Chair 
E. M. Petrosky 



A. L. Szeglin 
D. G. Thibault 



Subgroup on Strategy and Management 
(SC III, Divisions 1 and 2) 



P. A. Molvie, Chair 

S. V. Voorhees, Vice Chair 

G. Moino, Secretary 

T. L. Bedeaux 

D. C. Bixby 

G. Bynog 

j. Calland 

J. P. Chicoine 

C. M. Dove 
W. L. Haag, Jr. 
J. A. Hall 

J. D. Hoh 

D. J. Jenkins 
W. D. Lemos 



K. M. McTague 
B. W. Moore 

E. A. Nordstrom 
T. M. Parks 

J. L. Seigle 

R. V. Wielgoszinski 

F. P. Barton, Honorary 
Member 

R. B. Duggan, Honorary 

Member 
R. H. Weigel, Honorary 

Member 
J. I. Woodworth, Honorary 

Member 



Subgroup on Care and Operation of Heating Boilers (SC IV) 



S. V. Voorhees, Chair 
T. L. Bedeaux 
K. J. Hoey 



K. M. McTague 
P. A. Molvie 



R. W. Barnes, Chair 
J. R. Cole, Secretary 
B. K. Bobo 
N. Broom 

B. A. Erler 

C. M. Faidy 
J. M. Helmey 



M. F. Hessheimer 
R. S. Hill III 
E. V. Imbro 
R. M. Jessee 
R. F. Reedy 
Y. Urabe 



Special Working Group on Editing and Review (SC III) 



Subgroup on Cast Iron Boilers (SC IV) 



K. M. McTague, Chair 
T. L. Bedeaux 
J. P. Chicoine 
J. A. Hall 



P. A. Larkin 
W. D. Lemos 
C. P. McQuiggan 



Subgroup on Materials (SC IV) 



P. A. Larkin, Chair 
J. A. Hall 



W. D. Lemos 
J. L. Seigle 



R. F. Reedy, Chair 
W. H. Borter 
M. N. Bressler 
D. L. Caldwell 



R. P. Deubler 
B. A. Erler 
W. C. LaRochelle 
J. D. Stevenson 



Subgroup on Graphite Core Components (SC III) 



T. D. Burchell, Chair 
C. A. Sanna, Secretary 
R. L. Bratton 
M. W. Davies 
S. W. Doms 
S. F. Duffy 



O. Gelineau 
M. N. Mitchell 
N. N. Nemeth 
T. Oku 
M. Srinivasan 



JOINT ACI-ASME COMMITTEE ON 
CONCRETE COMPONENTS FOR NUCLEAR SERVICE (SC 3C) 



T. C. Inman, Chair 

A. C. Eberhardt, Vice Chair 
C. A. Sanna, Secretary 

N. Alchaar 
T. D. Al-Shawaf 
J. F. Artuso 
H. G. Ashar 
M. Elgohary 

B. A. Erler 
F. Farzam 



J. Gutierrez 

J. K. Harrold 

M. F. Hessheimer 

T. E. Johnson 

N.-H. Lee 

B. B. Scott 

R. E. Shewmaker 

J. D. Stevenson 

A. Y. C. Wong 

T. Watson, Liaison Member 



Subgroup on Water Heaters (SC IV) 



W. L. Haag, Jr., Chair 
J. Calland 
T. D. Gantt 
W. D. Lemos 



K. M. McTague 
F. J. Schreiner 
M. A. Taylor 
T. E. Trant 



Subgroup on Welded Boilers (SC IV) 



T. L. Bedeaux, Chair 
J. Calland 
C. M. Dove 
W. D. Lemos 



E. A. Nordstrom 

J. L. Seigle 

R. V. Wielgoszinski 



SUBCOMMITTEE ON 
NONDESTRUCTIVE EXAMINATION (SC V) 



J. E. Batey, Chair 

F. B. Kovacs, Vice Chair 
S. Vasquez, Secretary 

S. J. Akrin 
J. E. Aycock 
A. S. Birks 
P. L. Brown 
N. Y. Faransso 
A. F. Garbolevsky 

G. W. Hembree 
R. W. Kruzic 

J. F. Manning 
R. D. McGuire 



D. R. Quattlebaum, Jr. 

F. J. Sattler 

B. H. Clark, Jr., Honorary 

Member 
H. C. Graber, Honorary 

Member 
O. F. Hedden, Honorary 

Member 
J. R. MacKay, Honorary 

Member 
T. G. McCarty, Honorary 

Member 



xxni 



Subgroup on General Requirements/ 
Personnel Qualifications and Inquiries (SC V) 



Subgroup on Design (SC VIII) 



R. D. McGuire, Chair 
J. E. Batey 
A. S. Birks 
N. Y. Faransso 



G. W. Hembree 
J. W. Houf 
J. R. Mac Kay 
J. P. Swezy, Jr. 



Subgroup on Surface Examination Methods (SC V) 



A. S. Birks, Chair 
S. J. Akrin 
P. L. Brown 
N. Y. Faransso 
G. W. Hembree 



R. W. Kruzic 

D. R. Quattlebaum, Jr. 

F. J. Sattler 

M. J. Wheel 



U. R. Miller, Chair 

R. E. Knoblock, Secretary 

O. A. Barsky 

R. J. Basile 

M. R. Breach 

F. L. Brown 

J. R. Farr 

J. P. Glaspie 

C. E. Hinnant 

W. S. Jacobs 

M. D. Lower 

R. W. Mikitka 

K. Mokhtarian 



T. P. Pastor 
M. D. Rana 
G. B. Rawls, Jr. 
S. C. Roberts 
C. D. Rodery 
A. Selz 
S. C. Shah 
J. C. Sowinski 

C. H. Sturgeon 

D. A. Swanson 
K. K. Tarn 

E. L. Thomas, Jr. 
R. A. Whipple 



Subgroup on Volumetric Methods (SC V) 



Subgroup on Fabrication and Inspection (SC VIII) 



G. W. Hembree, Chair 

S. J. Akrin 

J. E. Aycock 

J. E. Batey 

P. L. Brown 

N. Y. Faransso 

A. F. Garbolevsky 



R. W. Hardy 
R. A. Kellerhall 
F. B. Kovacs 
R. W. Kruzic 
J. F. Manning 
F. J. Sattler 



C. D. Rodery, Chair 

E. A. Steen, Vice Chair 
J. L. Arnold 
L. F. Campbell 
H. E. Gordon 
W. S. Jacobs 

D. J. Kreft 



C. D. Lamb 
J. S. Lee 
B. R. Morelock 
M. J. Pischke 
M. J. Rice 
B. F. Shelley 
J. P. Swezy, Jr. 



Working Group on Acoustic Emissions (SG-VM) (SC V) 



Subgroup on General Requirements (SC VIII) 



N. Y. Faransso, Chair 
J. E. Aycock 



J. E. Batey 
J. F. Manning 



Working Group on Radiography (SG-VM) (SC V) 



F. B. Kovacs, Chair 

S. J. Akrin 

J. E. Aycock 

J. E. Batey 

P. L. Brown 

N. Y. Faransso 



A. F. Garbolevsky 
R. W. Hardy 
G. W. Hembree 
R. W. Kruzic 
T. L. Plasek 



Working Group on Ultrasonics (SG-VM) (SC V) 



R. W. Kruzic, Chair 
J. E. Aycock 
N. Y. Faransso 
O. F. Hedden 



R. A. Kellerhall 
J. F. Manning 
M. D. Moles 
F. J. Sattler 



SUBCOMMITTEE ON PRESSURE VESSELS (SC VIII) 



T. P. Pastor, Chair 

K. Mokhtarian, Vice Chair 

S. J. Rossi, Secretary 

R. J. Basile 

J. Cameron 

D. B. Demichael 

J. P. Glaspie 

M. Gold 

W. S. Jacobs 

G. G- Karcher 

K. T. Lau 

J. S. Lee 

R. Mahadeen 

S. Malone 

R. W. Mikitka 

U. R. Miller 



C. C. Neely 

D. T. Peters 
M. J. Pischke 
M. D. Rana 

G. B. Rawls, Jr. 
S. C. Roberts 
C. D. Rodery 
K. J. Schneider 
A. Selz 
J. R. Sims, Jr. 

E. A. Steen 
K. K. Tarn 
E. Upitis 

E. L. Thomas, Jr., Honorary 
Member 



S. C. Roberts, Chair 

D. B. Demichael, Secretary 

R. J. Basile 

J. P. Glaspie 

K. T. Lau 

M. D. Lower 

C. C. Neely 



A. S. Olivares 
F. L. Richter 
K. J. Schneider 
D. B. Stewart 
D. A. Swanson 
K. K. Tarn 



Subgroup on Heat Transfer Equipment (SC VIII) 



R. Mahadeen, Chair 
G. Aurioles, Secretary 
S. R. Babka 
J. H. Barbee 

0. A. Barsky 

1. G. Campbell 
M. D. Clark 

J. I. Gordon 
M. J. Holtz 
F. E. Jehrio 



B. J. Lerch 
S. Mayeux 
U. R. Miller 
T. W. Norton 
F. Osweiller 
R. J. Stastny 
S. Yokell 
R. P. Zoldak 

S. M. Caldwell, Honorary 
Member 



Subgroup on High-Pressure Vessels (SC VIII) 



J. R. Sims, Jr., Chair 

S. Vasquez, Secretary 

L. P. Antalffy 

R. C. Biel 

D. J. Burns 

P. N. Chaku 

R. D. Dixon 

M. E. Dupre 

D. M. Fryer 

W. Hitler 

A. H. Honza 

M. M. James 

P. Jansson 



J. A. Kapp 
J. Keltjens 

D. P. Kendall 
A. K. Khare 
M. D. Mann 
S. C. Mordre 
G. J. Mraz 

E. H. Perez 

D. T. Peters 

E. D. Roll 

F. W. Tatar 
S. Terada 



Subgroup on Materials (SC VIII) 



Subgroup on Performance Qualification (SC IX) 



J. Cameron, Chair 

E. E. Morgenegg, Secretary 

D. C. Agarwal 
J. F. Grubb 

E. L. Hibner 
M. Katcher 



W. M. Lundy 
E. G. Nisbett 

D. W. Rahoi 
R. C. Sutherlin 

E. Upitis 



Special Working Group on Graphite Pressure Equipment 
(SC VIII) 



S. Malone, Chair 
U. D'Urso, Secretary 
F. L. Brown 



M. R. Minick 
E. Soltow 
A. A. Stupica 



Special Working Group on High-Pressure Vessels (SC VIII) 

S. Vasquez, Secretary 

Task Group on Impulsively Loaded Vessels (SC VIII) 



R. E. Nickel I, Chair 
G. A. Antaki 
D. D. Barker 
R. C. Biel 
D. W. Bowman 
D. L. Caldwell 
A. M. Clayton 



J. E. Didlake, Jr. 
T. A. Duffey 
R. Forgan 
B. L. Haroldsen 
H. L. Heaton 
E. A. Rodriguez 
J. R. Sims, Jr. 



SUBCOMMITTEE ON WELDING (SC IX) 



J. G. Feldstein, Chair 

W. J. Sperko, Vice Chair 

J. D. Wendler, Secretary 

D. A. Bowers 

R. K. Brown, Jr. 

M. L. Carpenter 

L. P. Connor 

P. D. Flenner 

J. M. Given, Jr. 

J. S. Lee 

W. M. Lundy 



R. D. McGuire 

B. R. Newmark 

A. S. Olivares 

M. J. Pischke 

S. D. Reynolds, Jr. 

M. J. Rice 

M. B. Sims 

G. W. Spohn III 

M. J. Stanko 

P. L. Van Fosson 

R. R. Young 



D. A. Bowers, Chair 

V. A. Bell 

L. P. Connor 

R. B. Corbit 

P. R. Evans 

P. D. Flenner 

J. M. Given, Jr. 



K. L. Hayes 

J. S. Lee 

W. M. Lundy 

R. D. McGuire 

M. B. Sims 

G. W. Spohn III 



Subgroup on Procedure Qualification (SC IX) 



D. A. Bowers, Chair 
M. J. Rice, Secretary 
M. Bernasek 
R. K. Brown, Jr. 
A. S. Olivares 
S. D. Reynolds, Jr. 



M. B. Sims 
W. J. Sperko 
S. A. Sprague 
J. P. Swezy, Jr. 
P. L. Van Fosson 
T. C. Wiesner 



Honorary Member (SC IX) 



W. K. Scattergood 



SUBCOMMITTEE ON 
FIBER-REINFORCED PLASTIC PRESSURE VESSELS (SC X) 



D. Eisberg, Chair 

P. J. Conlisk, Vice Chair 

S. Vasquez, Secretary 

F. L. Brown 

J. L. Bustillos 

T. W. Cowley 

T. J. Fowler 

D. H. Hodgkinson 

L. E. Hunt 

D. L. Keeler 

B. M. Linnemann 



J. C. Murphy 
D. J. Painter 
D. J. Pinell 
G. Ramirez 
J. R. Richter 
J. A. Rolston 
B. F. Shelley 
F. W. Van Name 
D. O. Yancey, Jr. 
P. H. Ziehl 



Subgroup on Brazing (SC IX) 



M. J. Pischke, Chair 
E. W. Beckman 
L. F. Campbell 
M. L. Carpenter 



A. F. Garbolevsky 
C. F. Jeerings 
J. P. Swezy, Jr. 



Subgroup on General Requirements (SC IX) 



B. R. Newmark, Chair 
P. R. Evans 
R. M. Jessee 
A. S. Olivares 



H. B. Porter 
P. L. Sturgill 
K. R. Willens 



Subgroup on Materials (SC IX) 



M. L. Carpenter, Chair 

J. L. Arnold 

M. Bernasek 

L. P. Connor 

R. M. Jessee 

C. C. Kim 



T. Melfi 

S. D. Reynolds, Jr. 
C. E. Sainz 
W. J. Sperko 
M. J. Stanko 
R. R. Young 



SUBCOMMITTEE ON 
NUCLEAR INSERVICE INSPECTION (SC XI) 



G. C. Park, Chair 

R. W. Swayne, Vice Chair 

R. L. Crane, Secretary 

W. H. Bamford, Jr. 

R. C. Cipolla 

D. D. Davis 
R. L. Dyle 

E. L. Farrow 
R. E. Gimple 

F. E. Gregor 
K. Hasegawa 
D. O. Henry 
R. D. Kerr 

S. D. Kulat 

G. L. Lagleder 
D. W. Lamond 
J. T. Lindberg 
B. R. Newton 



W. E. Norris 

K. Rhyne 

W. R. Rogers III 

D. A. Scarth 

F. J. Schaaf, Jr. 

J. C. Spanner, Jr. 
J. E. Staffiera 

G. L. Stevens 

E. W. Throckmorton III 
D. E. Waskey 

R. A. West 

C. J. Wirtz 

C. S. Withers 

R. A. Yonekawa 

K. K. Yoon 

T. Yuhara 

Y.-S. Chang, Delegate 



Executive Committee (SC XI) 



Working Group on Pipe Flaw Evaluation (SG-ES) (SC XI) 



R. W. Swayne, Chair 
G. C. Park, Vice Chair 
R. L. Crane, Secretary 
W. H. Bamford, Jr. 
D. D. Davis 
R. L. Dyle 
R. E. Gimple 
F. E. Gregor 



O. F. Hedden 
C. G. McCargar 
W. E. Norris 
K. Rhyne 
F. J. Schaaf, Jr. 
J. C. Spanner, Jr. 
E. W. Throckmorton 
R. A. Yonekawa 



Honorary Members (SC XI) 



D. A. Scarth, Chair 

G. M. Wilkowski, Secretary 

T. A. Bacon 

W. H. Bamford, Jr. 

R. C. Cipolla 

N. G. Cofie 

S. K. Daftuar 

G. H. De Boo 

E. Friedman 
B. R. Ganta 
L. F. Goyette 



K. Hasegawa 
P. H. Hoang 
D. N. Hopkins 
K. Kashima 
H. S. Mehta 
K. Miyazaki 
J. S. Panesar 
P. J. Rush 
K. K. Yoon 
V. A. Zilberstein 



L. J. Chockie 
C. D. Cowfer 
O. F. Hedden 



J. P. Houstrup 

L. R. Katz 

P. C. Riccardella 



Subgroup on Liquid-Metal-Cooled Systems (SC XI) 

C. G. McCargar, Chair W. L. Chase 



Subgroup on Evaluation Standards (SC XI) 



Subgroup on Nondestructive Examination (SC XI) 



W. H. Bamford, Jr., Chair 

G. L. Stevens, Secretary 

R. C. Cipolla 

S. Coffin 

G. H. De Boo 

B. R. Ganta 

T. J. Griesbach 

K. Hasegawa 

D. N. Hopkins 

Y. Imamura 



K. Koyama 

D. R. Lee 

H. S. Mehta 

J. G. Merkle 

S. Ranganath 

D. A. Scarth 

K. R. Wichman 

K. K. Yoon 

Y.-S. Chang, Delegate 



J. C. Spanner, Jr., Chair 
G. A. Lofthus, Secretary 
N. R. Bentley 
T. L. Chan 

C. B. Cheezem 

D. R. Cordes 
F. J. Dodd 

F. E. Dohmen 
M. E. Gothard 



D. O. Henry 
M. R. Hum 
G. L. Lagleder 
J. T. Lindberg 
G. R. Perkins 
A. S. Reed 
F. J. Schaaf, Jr. 
C. J. Wirtz 



Working Group on Flaw Evaluation (SG-ES) (SC XI) 



R. C. Cipolla, Chair 

G. H. De Boo, Secretary 

W. H. Bamford, Jr. 

M. Basol 

J. M. Bloom 

B. R. Ganta 

T. J. Griesbach 

H. L. Gustin 

F. D. Hayes 

P. H. Hoang 

D. N. Hopkins 

Y. Imamura 

K. Koyama 

D. R. Lee 

H. S. Mehta 



J. G. Merkle 
M. A. Mitchell 
K. Miyazaki 
R. K. Qashu 
S. Ranganath 
P. J. Rush 
D. A. Scarth 
T. S. Schurman 
W. L. Server 

F. A. Simonen 
K. R. Wichman 

G. M. Wilkowski 
K. K. Yoon 

S. Yukawa 

V. A. Zilberstein 



Working Group on Personnel Qualification and Surface, 
Visual, and Eddy Current Examination (SG-NDE) (SC XI) 



D. R. Cordes, Secretary 

B. L Curtis 

N. Farenbaugh 

G. B. Georgiev 

D. O. Henry 

J. T. Lindberg 



D. R. Quattlebaum, Jr. 

A. S. Reed 

D. Spake 

J. C. Spanner, Jr. 

C.J. Wirtz 



Working Group on Pressure Testing (SG-WCS) (SC XI) 



D. W. Lamond, Chair 

J. M. Boughman, Secretary 

J. J. Churchwell 

G. L. Fechter 

K. W. Hall 



R. E. Hall 

J. K. McClanahan 

A. McNeill III 

B. L. Montgomery 
E. J. Sullivan, Jr. 



Working Group on Operating Plant Criteria (SG-ES) (SC XI) 



T. J. Griesbach, Chair 

K. R. Baker 

W. H. Bamford, Jr. 

H. Behnke 

B. A. Bishop 

T. L. Dickson 

S. R. Gosselin 

S. N. Malik 

H. S. Mehta 



R. Pace 

S. Ranganath 

W. L. Server 

E. A. Siegel 

F. A. Simonen 

G. L. Stevens 
D. P. Weakland 
K. K. Yoon 



Working Group on Procedure Qualification 
and Volumetric Examination (SG-NOE) (SC XI) 



M. E. Gothard, Chair 
G. R. Perkins, Secretary 
C. B. Cheezem 
A. D. Chockie 
S. R. Doctor 
F. J. Dodd 
F. E. Dohmen 
K. J. Hacker 



R. Kellerhall 
D. Kurek 
G. L. Lagleder 
G. A. Lofthus 
C. E. Moyer 
S. A. Sabo 
R. V. Swain 



Subgroup on Repair/Replacement Activities (SG-RRA)(SC XI) 



R. A. Yonekawa, Chair 

E. V. Farrell, Jr., Secretary 

S. B. Brown 

R. E. Cantrell 

P. D. Fisher 

E. B. Gerlach 

R. E. Cimple 

D. R. Graham 
R. A. Hermann 

E. V. Imbro 



R. D. Kerr 

S. L. McCracken 

B. R. Newton 
J. E. O'Sullivan 
W. R. Rogers III 
R. R. Stevenson 
R. W. Swayne 
D. E. Waskey 

J. G. Weicks 

C. S. Withers 



Working Group on Design and Programs (SG-RRA) (SC XI) 

E. B. Gerlach, Chair 



S. B. Brown, Secretary 
A. V. Du Bouchet 
G. G. Elder 
E. V. Farrell, Jr. 
S. K. Fisher 
J. M. Gamber 



D. R. Graham 
G. F. Harttraft 
R. R. Stevenson 
R. W. Swayne 
A. H. Taufique 
T. P. Vassallo, Jr. 
R. A. Yonekawa 



Working Group on Welding and Special Repair Process 
(SG-RRA) (SC XI) 



D. E. Waskey, Chair 

R. E. Cantrell, Secretary 

S. J. Findlan 

P. D. Fisher 

K. A. Gruss 

M. L. Hall 

R. A. Hermann 

R. P. Indap 



R. D. Kerr 
C. C Kim 
M. Lau 

S. L. McCracken 
B. R. Newton 
J. E. O'Sullivan 
J. G. Weicks 
K. R. Willens 



Subgroup on Water-Cooled Systems (SC XI) 

E. W. Throckmorton III, Chair S. D. Kulat 



J. M. Agold, Secretary 
G. L. Belew 
J. M. Boughman 

D. D. Davis 
H. Q. Do 

J. D. Ellis 

E. L Farrow 
M. J. Ferlisi 
O. F. Hedden 
M. L. Herrera 



D. W. Lamond 

A. McNeill III 

W. E. Norris 

D. Song 

J. E. Staff iera 

H. M. Stephens, Jr. 

K. B. Thomas 

R. A. West 

G. E. Whitman 

H. L Graves III, Alternate 



Working Group on Containment (SG-WCS) (SC XI) 

J. E. Staff iera, Chair 
H. Ashar 
S. G. Brown 
K. K. N. Chao 
R. C. Cox 
J. W. Crider 
M. J. Ferlisi 
H. L. Graves III 



H. T. Hill 
R. D. Hough 

C. N. Krishnaswamy 

D. Naus 

S. C. Petitgout 
H. M. Stephens, Jr. 
W. E. Norris, Alternate 



Working Group on ISI Optimization (SG-WCS) (SC XI) 



E. A. Siegel, Chair 
D. R. Cordes, Secretary 
R. L. Turner, Secretary 
W. H. Bamford, Jr. 
J. M. Boughman 
R. E. Hall 



A. H. Mahindrakar 
D. G. Naujock 
K. B. Thomas 
G. E. Whitman 
Y. Yuguchi 



Working Group on Implementation of Risk-Based Examination 
(SG-WCS) (SC XI) 



S. D. Kulat, Chair 

A. McNeill III, Secretary 
J. M. Agold 

S. A. Ali 

B. A. Bishop 

S. T. Chesworth 

C. Cueto-Felgueroso 
H. Q. Do 

R. Fougerousse 
M. R. Graybeal 
J. Hakii 



K. W. Hall 

D. W. Lamond 

J. T. Lindberg 

R. K. Mattu 

P. J. O'Regan 

N. A. Palm 

M. A. Pyne 

F. A. Simonen 

R. A. West 

J. C. Younger 

A. T. Keim, Alternate 



Working Group on Inspection of Systems and Components 

(SG-WCS) (SC XI) 



K. B. Thomas, Chair 

D. Song, Secretary 

V. L. Armentrout 

G. L Belew 

C. Cueto-Felgueroso 

H. Q. Do 

R. Fougerousse 

M. R. Hum 



S. D. Kulat 
D. G. Naujock 
T. Nomura 
C. M. Ross 
R. L. Turner 
R. A. West 
G. E. Whitman 



Working Group on General Requirements (SC XI) 



K. Rhyne, Chair 

E. J. Maloney, Secretary 

T. L. Chan 

J. D. Ellis 



E. L. Farrow 
R. K. Mattu 
S. R. Scott 
C. S. Withers 



Special Working Group on Editing and Review (SC XI) 



R. W. Swayne, Chair 
C. E. Moyer 



J. E. Staff iera 
C. J. Wirtz 



Special Working Group on Plant Life Extension (SC XI) 



T. A. Meyer, Chair 
D. V. Burgess, Secretary 
D. D. Davis 
F. E. Gregor 



P.-T. Kuo 
R. L. Turner 
G. G. Young 



Special Working Group on High-Temperature, Gas-Cooled 
Reactors (SC XI) 



J. Fletcher, Chair 

M. A. Lockwood, Secretary 

N. Broom 

K. N. Fleming 

W. A. O. Kriel 



B. J. Kruse 
M. N. Mitchell 
F. J. Schaaf, Jr. 
R. W. Swayne 



SUBCOMMITTEE ON TRANSPORT TANKS (SC XII) 



A. Selz, Chair 

L. Piano, Secretary 

P. D. Stumpf, Secretary 

A. N. Antoniou 

C. Becht IV 

M. L. Coats 

M. A. Garrett 

C. H. Hochman 

G. G. Karcher 



G. McRae 
M. R. Minick 
M. D. Pham 
M. D. Rana 
S. Staniszewski 
M. R. Toth 
A. P. Varghese 
S. V. Voorhees 



Subgroup on Design and Materials (SC XII) 



SUBCOMMITTEE ON DESIGN (SC-D) 



M. D. Rana, Chair 
G. G. Karcher 
S. L. McWilliams 
N. J. Paulick 
M. D. Pham 



T. A. Rogers 
A. P. Varghese 
M. R. Ward 
E. A. Whittle 



Subgroup on Fabrication and Inspection (SC XII) 



S. V. Voorhees, Chair 

J. A. Byers 

B. L. Gehl 

L. D. Holsinger 



D. J. Kreft 
G. McRae 
M. R. Minick 
A. S. Olivares 



Subgroup on General Requirements (SC XII) 



C. H. Hochman, Chair 
T. W. Alexander 

D. M. Allbritten 
C. A. Berts 

J. F. Cannon 
J. L. Freiler 
W. L Garfield 



M. A. Garrett 
K. L. Gilmore 
J. L. Rademacher 
T. Rummel 
M. R. Toth 
L. Wolpert 



SUBCOMMITTEE ON BOILER AND 
PRESSURE VESSEL ACCREDITATION (SC-BPVA) 



W. C. LaRochelle, Chair 

P. D. Edwards, Vice Chair 

K. I. Baron, Secretary 

M. B. Doherty 

P. Hackford 

K. T. Lau 

L. E. McDonald 

K. M. McTague 

B. R. Morelock 

J. D. O'Leary 

D. E. Tanner 

B. C. Turczynski 

D. E. Turtle 

E. A. Whittle 

G. By nog, Alternate 



M. A. DeVries, Alternate 

C. E. Ford, Alternate 

T. E. Hansen, Alternate 
G. L. Hollinger, Alternate 

D. J. Jenkins, Alternate 

B. B. MacDonald, Alternate 
R. D. Mile, Alternate 
G. P. Milley, Alternate 
T. W. Norton, Alternate 
H. R. Staehr, Alternate 
J. A. West, Alternate 
R. V. Wielgoszinski, Alternate 
O. E. Trapp, Senior Consultant 
A. J. Spencer, Honorary 
Member 



R. J. Basile, Chair 
R. W. Barnes 
M. R. Breach 
R. P. Deubler 
G. G. Graven 
G. L. Hollinger 
R. I. jetter 



D. P. Jones 
R. W. Mikitka 
U. R. Miller 
W. J. O'Donnell 
R. D. Schueler, Jr. 
A. Selz 



Subgroup on Design Analysis (SC-D) 



G. L. Hollinger, Chair 

S. A. Adams 

M. R. Breach 

R. G. Brown 

R. J. Gurdal 

C. F. Heberling II 

C. E. Hinnant 
P. Hirschberg 

D. P. Jones 
A. Kalnins 
W. J. Koves 



K. Matsunaga 
G. A. Miller 
W. D. Reinhardt 
D. H. Roarty 
G. Sannazzaro 
T. G. Seipp 

D. A. Swanson 
G. Taxacher 

E. L. Thomas, Jr. 
R. A. Whipple 



Subgroup on Elevated Temperature Design (SC-D) 



R. I. Jetter, Chair 
T. Asayama 

C. Becht IV 

J. F. Cervenka 

D. S. Griffin 
B. F. Hantz 
M. H. Jawad 
W. J. Koves 
S. Majumdar 
D. L. Marriott 



T. E. McGreevy 
K. A. Moore 
W. J. O'Donnell 
D. A. Osage 
J. S. Porowski 
B. Riou 
T.-L. Sham 
M. S. Shelton 
R. W. Swindeman 



Subgroup on Fatigue Strength (SC-D) 



W. J. O'Donnell, Chair 

S. A. Adams 

P. R. Donavin 

R. J. Gurdal 

C. F. Heberling II 

P. Hirschberg 

P. Hsu 



D. P. Jones 
G. Kharshafdjian 
S. Majumdar 
T. Nakamura 
D. H. Roarty 
G. Taxacher 
H. H. Ziada 



Subgroup on Openings (SC-D) 



SUBCOMMITTEE ON NUCLEAR ACCREDITATION (SC-NA) 



R. R. Stevenson, Chair 

W. C. LaRochelle, Vice Chair 

J. Pang, Secretary 

M. N. Bressler 

S. M. Goodwin 

K. A. Huber 

M. Kotb 

J. C. Krane 

C. A. Lizotte 

R. P. Mclntyre 

M. R. Minick 

H. B. Prasse 

T. E. Quaka 

A. T. Roberts III 



D. E. Tanner 

D. M. Vickery 

G. Bynog, Alternate 
G. Deily, Alternate 
P. D. Edwards, Alternate 
J. W. Highlands, Alternate 
K. M. Hottle, Alternate 
B. G. Kovarik, Alternate 
P. F. Prescott, Alternate 
S. Toledo, Alternate 

E. A. Whittle, Alternate 

R. V. Wielgoszinski, Alternate 

H. L. Wiger, Alternate 

O. E. Trapp, Senior Consultant 



M. R. Breach, Chair 
R. W. Mikitka, Secretary 
G. G. Graven 
V. T. Hwang 
J. C. Light 
R. B. Luney 



J. P. Madden 

D. R. Palmer 
J. A. Pfeifer 
M. D. Rana 

E. C. Rodabaugh 



Special Working Group on Bolted Flanged Joints (SC-D) 



R. W. Mikitka, Chair 
G. D. Bibel 
H. A. Bouzid 
A. Chaudouet 
E. Michalopoulos 
S. N. Pagay 



J. R. Payne 

P. G. Scheckermann 

R. W. Schneider 

R. D. Schueler, Jr. 

A. Selz 

M. S. Shelton 



SUBCOMMITTEE ON 
SAFETY VALVE REQUIREMENTS (SC-SVR) 



S. F. Harrison, Jr., Chair 

J. A. West, Vice Chair 

S. J. Rossi, Secretary 

J. F. Ball 

S. Cammeresi 

A. Cox 

R. D. Danzy 

D. B. Demichael 

R. J. Doelling 



J. P. Glaspie 
H. I. Gregg 
W. F. Hart 

C. A. Neumann 
T. M. Parks 

D. K. Parrish 
D. J. Scallan 
J. C. Standfast 
Z. Wang 



Subgroup on Design (SC-SVR) 



J. A. West, Chair 
C. E. Beair 
R. D. Danzy 
R. J. Doelling 



H. I. Gregg 
D. Miller 
T. Patel 
T. R. Tarbay 



Subgroup on General Requirements (SC-SVR) 



D. B. Demichael, Chair 
J. F. Ball 
G. Brazier 
J. P. Glaspie 
C. A. Neumann 



T. M. Parks 
D. K. Parrish 
J. W. Ramsey 
J. W. Richardson 
J. C. Standfast 



A. Cox, Chair 
J. E. Britt 
S. Cammeresi 
G. D. Goodson 



Subgroup on Testing (SC-SVR) 

W. F. Hart 
K. G. Roth 
D. J. Scallan 
Z. Wang 



U.S. Technical Advisory Group ISO/TC 185 
Safety Relief Valves 

T. J. Bevilacqua, Chair Y.-S. Lai 

S. J. Rossi, Secretary D. Miller 

S. F. Harrison, Jr. J. A. West 



PERSONNEL 
Officers of ASTM Committee 

(Cooperating in the Development of the Specifications Herein) 
As of January 1, 2007 

D-20 ON PLASTICS 



D. M. Oates, Chair A. D. Kupfer, Products Vice 

F. A. Boldt, Materials Vice Chair 

Chair M. L. Lavach, Membership 

G. R. Cornell, Programs Vice Vice Chair 

Chair K. Morgan, Staff Manager 

K. Donohue, Administrative S. E. Osborn, Secretary 

Assistant H. E. Yohn, Methods Vice 
J. Galipeau, Liaison Research Chair 

Special Vice Chair 



PREAMBLE 



The rules of this Section of the Code cover minimum 
construction requirements for the design, fabrication, 
installation, and inspection of steam heating, hot water 
heating, hot water supply boilers that are directly fired with 
oil, gas, electricity, coal, or other solid or liquid fuels, and 
for operation at or below the pressure and temperature 
limits set forth in this document. Similar rules for potable 
water heaters are also included. 

For Section IV application, the boiler proper or other 
vessels terminate at the supply and return connections to 
the system or the supply and feedwater connections of a 
hot water supply boiler. These connections may be any of 
the following: 

(a) the first circumferential joint for welding end con- 
nections 

(b) the face of the first flange in bolted flanged connec- 
tions 

(c) the first threaded joint in that type of connection 
Included within the scope of the boiler are pressure- 
retaining covers for inspection openings, such as manhole 
covers, handhold covers, and plugs; and headers required 
to connect individual coils, tubes, or cast sections within 
a boiler. 

The rules are divided into four major Parts: Part HG, 
applying to all materials of construction except as provided 
for in Part HLW; Part HF, applying to assemblies fabricated 
of wrought material, except as provided for in Part HLW; 
Part HC, applying to cast iron assemblies; Part HA, 
applying to boilers constructed of cast aluminum; and Part 



HLW, applying to potable water heaters. Part HF is further 
subdivided into Subpart HW, containing rules for welded 
construction, and Subpart HB, containing rules for brazed 
construction. 

The Parts and Subparts of this Section are divided into 
Articles. Each Article is given a number and a title, as for 
example, Part HG, Article 3, Design. Articles are divided 
into paragraphs that are given a three-digit number, the 
first of which corresponds to the Article number. Thus, 
under Article 3 of Part HG, paragraph HG-307 will be 
found. Paragraphs are further subdivided into subpara- 
graphs. Major subdivisions of paragraphs are designated 
by three- or four-digit numbers followed by a decimal 
point and a digit or digits. Where necessary, further subdi- 
visions are represented by letters and then by numbers in 
parentheses. Minor subdivisions of the paragraphs are also 
represented by letters. A reference to one of these para- 
graphs in the text of the Section includes all of the applica- 
ble rules in that paragraph. Thus, reference to HG-307 
includes all the rules in HG-307. 1 through HG-307.4. 

This Section does not contain rules to cover all possible 
details of design and construction. Where complete details 
are not given, it is intended that the manufacturer, subject 
to the acceptance of the Authorized Inspector, shall provide 
details of design and construction that will be as safe as 
otherwise required by these rules. 

When the strength of any part cannot be computed with 
a satisfactory assurance of safety, these rules provide proce- 
dures for establishing its maximum allowable working 
pressure. 



xxxui 



SUMMARY OF CHANGES 

The 2007 Edition of this Code contains revisions in addition to the 2004 Edition with 2005 and 2006 Addenda. 
The revisions are identified with the designation 07 in the margin and, as described in the Foreword, become 
mandatory six months after the publication date of the 2007 Edition. To invoke these revisions before their 
mandatory date, use the designation "2007 Edition" in documentation required by this Code. If you choose not 
to invoke these revisions before their mandatory date, use the designation "2004 Edition through the 2006 
Addenda" in documentation required by this Code. 

The BC numbers listed below are explained in more detail in "List of Changes in BC Order" following this 
Summary of Changes. 

Changes given below are identified on the pages by a margin note, 07, placed next to the affected area. 



Page 
33, 34 

43 
46^9 



62 
70 
77-82 



Location 
HG-400.1(b) 
HG-400.2(d) 
HG-510 
HG-530.1 
Fig. HG-530.2 
Fig. HG-530.4 
HG-530.2 

Fig. HG-530.6 
HG-530.2(e)(5) 
HG-715(c) 
HF-301.1 
Table HF-300.2 



Table HF-300.2M 



112 


HC-100 


120 


HC-320 


122 


HC-410.2 


126-134 


Part HA 


143 


Table HLW-300 


148 


HLW-402 


1 69, 1 70 


HLVV-8 10(a) 



Change (BC Number) 

Revised (BC06-531) 

Revised (BC06-531) 

Subparagraphs (b) and (c) revised (BC06-952) 

Heading revised (BC03-1578) 

Revised (BC06-1383) 

Revised (BC06-1383) 

(1) Heading revised (BC03-1578) 

(2) Subparagraph (a)(1) revised (BC03-1578) 

Revised (BC06-1383) 
Revised (BC03-1578) 
Revised (BC05-1410) 
Subparagraphs (b), (c), and (d) revised (BC06-143) 

(1) Revised to include SB-111 under "Aluminum 
Bronze" (BC02-2473) 

(2) Revised to include SB/EN 1706 under "Casting, 
Bronze, Brass, and Aluminum" (BC05-1220) 

(1) Revised to include SB-1 1 1 under "Aluminum 
Bronze" (BC02-2473) 

(2) Revised to include SB/EN 1706 under "Casting, 
Bronze, Brass, and Aluminum" (BC05-1220) 

Revised (BC06-485) 

Revised (BC05-1411) 

First and second sentences revised (BC06-530) 

Added (BC03-1578) 

SA-181, Class 70 added (BC05-1416) 

In the first sentence, HLW-302 corrected by errata to 
read HLW-303 (BC06-473) 

(1) First sentence revised; second sentence added 
(BC05-1410) 

(2) In the last sentence, 19 mm corrected by errata to 
read DN 20 (BC06-473) 



211, 212 


Form H-5A 


Added (BC03-1578) 


216 


Form HA-1 


Added (BC03-1578) 


217 


Form HA-2 


Added (BC03-1578) 



NOTE: Volume 57 of the Interpretations to Section IV of the ASME Boiler and Pressure Vessel Code follows 
the last page of this Edition. 



xxxv 



LIST OF CHANGES IN BC ORDER 



BC Number 

BC02-2473 
BC03-1578 



BC05-1220 

BC05-1410 

BC05-1411 
BC05-1416 
BC06-143 

BC06-473 

BC06-485 
BC06-530 
BC06-531 

BC06-952 

BC06-1383 



Change 



Incorporated Code Case 2314 by adding SB- 111, UNS C60800 to Table HF-300. 

Added a new Part HA containing rules for hot water heating boilers constructed primarily of cast aluminum sec- 
tion(s) to be used in conjunction with Part HG. Also revised para. HG-530 (stamping of boilers) to reflect addi- 
tion of new Part HA. 

A cover sheet for SB/EN1706 will be added to Section n, Part B. In Section IV, it incorporates Code Case 
2383-2 by adding SB/EN1706 EN AC4300 to Table HF-300.2 

Revised HG-715(c) and HLW-810(a) to clarify that the connection should be made at the lowest practicable point 
on the boiler/water heater or lowest point on piping connected to the boiler/water heater. 
Revised HC-320 to clarify requirements pertaining to non-load-bearing heat transmitting fins and pins. 
Added SA-181 Class 70 to the existing list of SA-181 grades found in Table HLW-300. 
Revised HF-30 1.1(b) by deleting "or those calculated as cylindrical parts under external pressure (HG-312.1 to 
HG-312.6)," revised (c) by adding "and HG-312.1(a)," and revised (d) by adding "and HG-312.1 (a)," to clarify 
minimum thickness exemption for SA-240 Type 316 Ti material. 

Revised reference to HLW-302 in HLW-402, revised metric equivalent from (19 mm) to DN 20 under HLW-810, 
and revised title of HG-307.4. 

Revised HC-100 by adding the word "sections" after "primarily of cast iron." 

Revised para. HC-410.2 by replacing "working pressure" with "maximum allowable working pressure." 
Revised paras. HG-400.1(b) and HG-400.2(d) to limit maximum safety valve and safety relief valve size to 
NPS 4 (DN100). 

Corrected paragraph reference in HG-5 10(b); deleted part of HG-5 10(c), all of HG-5 10(c)(1), and part of 
HG-5 10(c)(2); and revised HG-5 10(c)(2) to eliminate the confusion of the upper limit of the hydrostatic test. 
Reinstated the "steam MAWP" line on Figs. HG-530.2, HG-530.4, and HG-530.6. 



# 



XXXVI 



2007 SECTION IV 



PART HG 

GENERAL REQUIREMENTS FOR 

ALL MATERIALS OF 

CONSTRUCTION 



ARTICLE 1 
SCOPE AND SERVICE RESTRICTIONS 



HG-100 SCOPE 

(a) The rules of Part HG apply to steam heating boilers, 
hot water heating boilers, hot water supply boilers, and to 
appurtenances thereto. They shall be used in conjunction 
with the specific requirements in Part HF, Boilers of 
Wrought Materials, and Part HC, Cast Iron Boilers, which- 
ever is applicable. The foreword provides the basis for 
these rules. Part HG is not intended to apply to potable 
water heaters except as provided for in Part HLW. 

(b) This Part contains mandatory requirements, specific 
prohibitions, and nonmandatory guidance for materials, 
designs, fabrication, examination, inspection, testing, certi- 
fication, and pressure relief. 

(c) Laws or regulations issued by a municipality, state, 
provincial, federal, or other enforcement or regulatory body 
having jurisdiction at the location of an installation, estab- 
lish the mandatory applicability of these rules, in whole 
or in part. 

HG-101 SERVICE RESTRICTIONS 

HG-101.1 Service Restrictions. The rules of this Sec- 
tion are restricted to the following services: 

(a) steam boilers for operation at pressures not 
exceeding 15 psi (100 kPa) 

(b) hot water heating boilers and hot water supply boil- 
ers for operating at pressures not exceeding 160 psi 



(1 100 kPa) and /or temperatures not exceeding 250°F 
(120°C), at or near the boiler outlet, except that when some 
of the wrought materials permitted by Part HF are used, 
a lower temperature is specified 

HG-101.2 Services in Excess of Those Covered by 
This Section. For services exceeding the limits specified 
in HG-101.1, the rules of Section I shall apply. 



HG-102 UNITS 

Either U.S. Customary, SI, or any local customary units 
may be used to demonstrate compliance with all require- 
ments of this edition (e.g., materials, design, fabrication, 
examination, inspection, testing, certification, and over- 
pressure protection). 

In general, it is expected that a single system of units 
shall be used for all aspects of design except where unfeasi- 
ble or impractical. When components are manufactured at 
different locations where local customary units are different 
than those used for the general design, the local units 
may be used for the design and documentation of that 
component. Similarly, for proprietary components or those 
uniquely associated with a system of units different than 
that used for the general design, the alternate units may be 
used for the design and documentation of that component. 



2007 SECTION IV 



For any single equation, all variables shall be expressed 
in a single system of units. When separate equations are 
provided for U.S. Customary and SI units, those equations 
must be executed using variables in the units associated 
with the specific equation. Data expressed in other units 
shall be converted to U.S. Customary or SI units for use 
in these equations. The result obtained from execution of 
these equations may be converted to other units. 

Production, measurement and test equipment, drawings, 
welding procedure specifications, welding procedure and 
performance qualifications, and other fabrication docu- 
ments may be in U.S. Customary, SI, or local customary 
units in accordance with the fabricator's practice. When 
values shown in calculations and analysis, fabrication doc- 
uments, or measurement and test equipment are in different 
units, any conversions necessary for verification of Code 
compliance and to ensure that dimensional consistency is 
maintained shall be in accordance with the following: 

(a) Conversion factors shall be accurate to at least four 
significant figures. 

(b) The results of conversions of units shall be expressed 
to a minimum of three significant figures. 



Conversion of units, using the precision specified above 
shall be performed to assure that dimensional consistency 
is maintained. Conversion factors between U.S. Customary 
and SI units may be found in the Nonmandatory 
Appendix M, Guidance for the Use of U.S. Customary and 
SI Units in the ASME Boiler and Pressure Vessel Code. 
Whenever local customary units are used the Manufacturer 
shall provide the source of the conversion factors, which 
shall be subject to verification and acceptance by the 
Authorized Inspector. 

Material that has been manufactured and certified to 
either the U.S. Customary or SI material specification (e.g., 
SA-516M) may be used regardless of the unit system used 
in design. Standard fittings (e.g., flanges, elbows, etc.) that 
have been certified to either U.S. Customary units or SI 
units may be used regardless of the unit system used in 
design. 

All entries on a Manufacturer's Data Report and data 
for Code required nameplate marking shall be in units 
consistent with the fabrication drawings for the component 
using U.S. Customary, SI, or local customary units. It is 
acceptable to show alternate units parenthetically. Users 
of this Code are cautioned that the receiving Jurisdiction 
should be contacted to ensure the units are acceptable. 



2007 SECTION IV 



ARTICLE 2 
MATERIAL REQUIREMENTS 



HG-200 GENERAL MATERIAL 
REQUIREMENTS 
HG-200.1 Materials Subject to Pressure Stress. 

Material subject to stress due to pressure shall conform to 
one of the specifications given in Section II and shall be 
limited to those that are permitted in HF-200 for boilers 
of wrought materials and HC-200 for cast iron boilers. 

HG-200.2 Internal Parts Subject to Deterioration. 

Materials shall not be used for internal parts that are liable 
to fail due to deterioration when subjected to saturated 
steam temperatures at or below the maximum allowable 
working pressure. 

HG-200.3 Materials Not Found in Section II. Mate- 
rial not covered by specifications in Section II shall not 
be used unless authorization to use the material is granted 
by the Boiler and Pressure Vessel Committee on the basis 
of data submitted to the Committee in accordance with 
Appendix A. 

HG-200.4 Materials Use Not Limited by Specifica- 
tion Title. The title or scope paragraph of a material speci- 
fication in Section II with respect to product form or service 
shall not limit the use of a material, provided the material 
is suitable for the application and its use is permitted by 
the rules of this Section. 

HG-200.5 Materials Use Not Limited by Method of 
Production. Materials covered by specifications in Section 
II are not restricted as to the method of production unless 



so stated in the Specification, and as long as the product 
complies with the requirements of the Specification. 

HG-200.6 Materials With Thicknesses Exceeding 
Specification Limits. Materials having thicknesses outside 
of the limits given in the title or scope clause of a specifica- 
tion in Section II may be used in construction, provided 
they comply with the other requirements of the Specifica- 
tion and with all thickness requirements of this Code. 

HG-200.7 Nonpressure Part Materials. Material for 
nonpressure parts, such as skirts, supports, baffles, lugs, 
clips, and extended heat-transfer surfaces, need not con- 
form to the specifications for the material to which they 
are attached or to a material specification permitted in 
HF-200 or HC-200; but, if welded, they shall be of weld- 
able quality. The allowable stress value shall not exceed 
80% of the maximum allowable stress permitted for similar 
material in Tables HF-300.1 and HF-300.2. Satisfactory 
performance of a specimen in such service shall not make 
the material acceptable for use in pressure parts of a vessel. 



HG-201 SPECIFIC MATERIAL 
REQUIREMENTS 

Specific material requirements for assemblies con- 
structed of wrought materials are given in Part HF, Article 
2 and for assemblies constructed of cast iron in Part HC, 
Article 2. 



2007 SECTION IV 



ARTICLE 3 
DESIGN 



HG-300 DESIGN PRESSURE 

(a) The design pressure is the pressure used in the for- 
mulas of this Article, in conjunction with the allowable 
stress values, design rules, and dimensions specified for 
determining the minimum required thicknesses for the parts 
of a boiler. The design pressure for a heating boiler shall 
be at least 30 psi (200 kPa). 

(b) The term maximum allowable working pressure 
refers to gage pressure, or the pressure in excess of the 
atmospheric pressure in the boiler. The maximum allow- 
able working pressure, as stamped on the boiler per 
HG-530, must be less than or equal to the design pressure 
for any of its parts. 

(c) No boiler shall be operated at a pressure higher than 
the maximum allowable working pressure except when the 
safety valves or relief valves are discharging, at which time 
the maximum allowable working pressure shall not be 
exceeded by more than the amount specified in HG-400. 1 
and HG-400.2. 

HG-300.1 Vacuum Boilers. Rules for factory sealed 
boilers to be operated only under vacuum conditions are 
given in Appendix 5. 



HG-301 CYLINDRICAL PARTS UNDER 
INTERNAL PRESSURE 
HG-301. 1 General. The required thickness and the 
design pressure of cylindrical shells, tubes, pipe, and head- 
ers shall be determined in accordance with the following 
formulas: 

PR 



t = 



SE - 0.6P 



P = 



SEt 
R + 0.6t 



where 



E = efficiency of longitudinal joint or of ligament 
between tube holes, whichever is the lesser. For 
welded joints, use the efficiency specified in 
HW-702. For seamless shells, use E = 1 . 

P = design pressure [but not less than 30 psi (200 kPa)] 

R = inside radius of cylinder 



S = maximum allowable stress value from Tables 

HF-300.1 andHF-300.2 
t = required wall thickness 

HG-301.2 Tubes 

(a) The required thickness of tubes and pipes used as 
tubes shall be determined in accordance with the formulas 
in HG-301.1, adding to that value a minimum additional 
thickness of 0.04 in. (1 mm) as an allowance for rolling 
and structural stability. The additional 0.04 in. (1 mm) 
thickness is not required for tubes strength welded to tube- 
sheets, headers, or drums. 

(b) In no case shall the thickness of a tube or pipe used 
as a tube when installed by welding or rolling be less than 
0.061 in. (1.5 mm) at the point where it attaches to the 
tubesheet, header, or drum. There is no minimum thickness 
requirement for nonferrous tubes installed by brazing, 
except that the thickness used must meet the brazing quali- 
fication requirements of Section IX, Part QB. 



HG-305 FORMED HEADS, PRESSURE ON 
CONCAVE SIDE 

HG-305.1 General. The required thickness at the thin- 
nest point after forming 1 of ellipsoidal, torispherical, and 
hemispherical heads under pressure on the concave side 
(plus heads) shall be computed by the appropriate formulas 
in this paragraph. 

(a) Notation. The symbols used in this paragraph are 
defined as follows: 

D = inside diameter of the head skirt; or inside length 
of the major axis of an ellipsoidal head; or inside 
diameter of a cone head at the point under consid- 
eration, measured perpendicular to the longitudi- 
nal axis 

E = lowest efficiency of any joint in the head. For 
welded joints, use the efficiency specified in 



In order to insure that a finished head is not less than the minimum 
thickness required, it is customary to use a thicker plate to take care of 
possible thinning during the process of forming. The neck of an opening 
in a head with an integrally flanged opening will thin out due to the 
fluing operation. This is permissible provided the neck thickness is not 
less than the minimum thickness specified in HG-301 or the thickness 
required for a cylindrical shell having a diameter equal to the maximum 
diameter of the opening. (See HG-323.) 



2007 SECTION IV 



HW-702. For seamless heads, use E=l, except 
for hemispherical heads furnished without a skirt, 
in which case use the efficiency of the head-to- 
shell joint. 

L = inside spherical or crown radius 

P = design pressure [but not less than 30 psi (200 kPa)] 

S = maximum allowable stress value as given in 
Tables HF-300.1 and HF-300.2 

t = required wall thickness after forming 

HG-305.2 Ellipsoidal Heads. The required thickness 
and the design pressure of a dished head of semiellipsoidal 
form, in which half the minor axis (inside depth of the head 
minus the skirt) equals one-fourth of the inside diameter 
of the head skirt, shall be calculated by the following 
formulas: 



t = 



PD 



2SE - 0.2P 



or 



P = 



2SEt 
D + 0.2t 



HG-305.3 Torispherical Heads. The required thick- 
ness and the design pressure of a torispherical head shall 
be calculated by the following formulas (see HG-305.6): 






0.885PL 
SE-0AP 



or 



(c) the stays are through-stays attached to the head by 
outside and inside nuts 

(d) the design pressure on the head is taken as that 
calculated for an unstayed formed head plus the pressure 
calculated for the stays by the formula for stayed surfaces 
in HG-340 using a value of C = 1.63 

HG-305.6 Inside Crown Radius of Unstayed Heads. 

The inside crown radius to which an unstayed formed head 
is dished shall be not greater than the outside diameter 
of the skirt of the head. The inside knuckle radius of a 
torispherical head shall be not less than 6% of the outside 
diameter of the skirt of the head but in no case less than 
three times the head thickness. 

HG-305.7 Heads Built Up of Several Shapes. A head 
for a cylindrical shell may be built up of several head 
shapes, the thicknesses of which satisfy the requirements 
of the appropriate formulas above, provided that adjoining 
shapes are so formed that they have a common tangent 
transverse to the joint. 

HG-305.8 Length of Skirts. The required length of 
skirt on heads concave and convex to pressure shall comply 
with HW-715. 

HG-305.9 Permissible Diameter of Flat Spots on 
Formed Heads. If a torispherical, ellipsoidal, or hemi- 
spherical head is formed with a flattened spot or surface, 
the diameter of the flat spot shall not exceed that permitted 
for flat heads as given by the formula in HG-307, using 
C = 0.20. 



P = 



SEt 



0.885L + O.lf 



HG-305.4 Hemispherical Heads. The required thick- 
ness and the design pressure of a hemispherical head in 
which P does not exceed 0.665SE shall be calculated by 
the following formulas: 



t = 



PL 



2SE - 0.2P 



or 



P = 



2SEt 
L + 0.2t 



HG-305.5 Formed Heads With Stays. A formed head 
of a lesser thickness than that required by the rules of this 
paragraph may be used provided it is stayed as a flat surface 
according to the rules of HG-340 for stayed flat plates, no 
allowance being made in such staying for the holding 
power due to the curvature of the head unless all the follow- 
ing conditions are met: 

(a) the head is at least two-thirds as thick as required 
by the rules of this paragraph for an unstayed head 

(b) the head is at least \ in. (22 mm) thick 



HG-306 FORMED HEADS, PRESSURE ON 
CONVEX SIDE 
HG-306.1 Unstayed dished heads with the pressure on 
the convex side shall have a design pressure equal to 60% 
of that for heads of the same dimensions having the pres- 
sure on the concave side (see HG-305). 

HG-307 FLAT HEADS 

HG-307. 1 General. The minimum thickness of 
unstayed heads, cover plates, and blind flanges shall con- 
form to the requirements given in this paragraph. These 
requirements apply to both circular and noncircular heads 
and covers. In addition, flat heads or covers made of cast 
iron shall be subjected to the proof test provisions of 
HG-500. Some acceptable types of flat heads and covers 
are shown in Fig. HG-307. 

{a) The symbols used in this paragraph and Fig. HG-307 
are denned as follows: 

C = a factor depending upon the method of attachment 
of the head, shell, pipe, or header dimensions, and 
other items as listed in HG-307 .4 below, dimen- 
sionless. The factors for welded covers also 



2007 SECTION IV 



include a factor of 0.667 that effectively increases 

the allowable stress for such construction to 1.55. 
D = long span of noncircular heads or covers measured 

perpendicular to short span 
d = diameter, or short span, measured as indicated in 

Fig. HG-307 
H G = gasket moment arm, equal to the radial distance 

from the center line of the bolts to the line of 

the gasket reaction, as shown in Fig. HG-307, 

sketches (j) and (k) 
L = perimeter of noncircular bolted head measured 

along the centers of the bolt holes 
/ = length of flange or flanged heads, measured from 

the tangent line of knuckle, as indicated in Fig. 

HG-307, sketches (a) and (c) 
m = the ratio t r lt s , dimensionless 
P = design pressure 

r = inside corner radius on the head formed by flang- 
ing or forging 
S =■ maximum allowable stress value using values 

given in Tables HF-300.1 and HF-300.2 
t = minimum required thickness of flat head or cover 
t e = minimum distance from beveled end of drum, 

pipe, or header, before welding, to outer face of 

head, as indicated in Fig. HG-307, sketch (i), 
tf = actual thickness of the flange on a forged head, 

at the large end, as indicated in Fig. HG-307, 

sketch (b) 
t h = actual thickness of flat head or cover 
t r = required thickness of seamless shell, pipe, or 

header, for pressure 
t s = actual thickness of shell, pipe, or header 
t w = thickness through the weld joining the edge of a 

head to the inside of a drum, pipe, or header, as 

indicated in Fig. HG-307, sketch (g) 
?i = throat dimension of the closure weld, as indicated 

in Fig. HG-307, sketch (r) 
W = total bolt load as further defined in HG-307. 2 
Z = a factor for noncircular heads and covers that 

depends on the ratio of short span to long span, 

as given in HG-307. 2 below, dimensionless 

HG-307.2 Thickness of Circular, Flat, Unstayed 
Heads, Covers, and Blind Flanges. The thickness of flat 
unstayed heads, covers, and blind flanges shall conform to 
one of the following requirements: 2 

(a) Circular blind flanges of ferrous materials conform- 
ing to ANSI B16.5 shall be acceptable for the diameters 
and pressure-temperature ratings in Tables 2 to 8 of that 
Standard when of the types shown in Fig. HG-307, sketches 
(j) and (k). 



The formulas provide safe construction as far as stress is concerned. 
Greater thicknesses may be necessary if deflection would cause leakage 
at threaded or gasketed joints. 



(b) The minimum required thickness of flat unstayed 
circular heads, covers, and blind flanges shall be calculated 
by the following formula: 



t = dJcFTs 



(1) 



except when the head, cover, or blind flange is attached 
by bolts causing an edge moment [Fig. HG-307, sketches 
(j) and (k)], in which case the thickness shall be calcu- 
lated by 



* = d JcP/S+ l.9WH G /Sd 3 



(2) 



When using Formula (2), the thickness t shall be calcu- 
lated for both operating conditions and gasket seating, and 
the greater of the two values shall be used. For operating 
conditions, the value of P shall be the design pressure, the 
value of S at design temperature shall be used, and W shall 
be the sum of the bolt loads required to resist the end 
pressure load and to maintain tightness of the gasket. For 
gasket seating, P equals zero, the value of S at atmospheric 
temperature shall be used, and W shall be the average of 
the required bolt load and the load available from the bolt 
area actually used. 

HG-307.3 Thickness of Noncircular, Flat, Unstayed 
Heads, Covers, and Blind Flanges 

(a) Flat unstayed heads, covers, or blind flanges may 
be square, rectangular, elliptical, obround, segmental, or 
otherwise noncircular. Their required thickness shall be 
calculated by the following formula: 



t = d JzcpTs 



where 



Z = 3.4 - 



lAd 
D 



(3) 



(4) 



with the limitation that Z need not be greater than 2.5. 

(b) Formula (3) does not apply to noncircular heads, 
covers, or blind flanges attached by bolts causing a bolt 
edge moment [Fig. HG-307, sketches (j) and (k)]. For 
noncircular heads of this type, the required thickness shall 
be calculated by the following formula: 



t = dy/zCP/S + 6WH n /SLd 2 



(5) 



When using Formula (5), the thickness t shall be calcu- 
lated in the same way as specified above for Formula (2). 

HG-307.4 Values of C for Use in Formulas in 
HG-307.2 and HG-307.3. For the types of construction 
shown in Fig. HG-307, the values of C to be used in 
Formulas (1), (2), (3), and (5) are as follows: 

(a) Figure HG-307, sketch (a): C = 0.17 for flanged 
circular and noncircular heads forged integral with or butt 
welded to the shell, pipe, or header, with an inside corner 
radius not less than three times the required head thickness, 



2007 SECTION IV 



with no special requirement with regard to length of flange, 
and where the welding meets all the requirements for cir- 
cumferential joints given in Part HF, Subpart HW. 

C = 0.10 for circular heads, when the flange length for 
heads of the above design is not less than 



/= 1.1 - 0.8 ^j/^ 



(6) 



• 



When C = 0.10 is used, the taper shall be at least 1:3. 

(b) Figure HG-307, sketch (b): C = 0.17 for circular 
and noncircular heads forged integral with or butt-welded 
to the shell, pipe, or header, where the corner radius on 
the inside is not less than three times the thickness of the 
flange and where the welding meets all the requirements 
for circumferential joints given in Part HF, Subpart HW. 

(c) Figure HG-307, sketch (c): C = 0.20 for circular 
flanged plates screwed over the end of the shell, pipe, or 
header, with inside corner radius not less than 3t, in which 
the design of the threaded joint against failure by shear, 
tension, or compression, resulting from the end force due 
to pressure, is based on a factor of safety of at least five, 
and the threaded parts are at least as strong as the threads 
for standard piping of the same diameter. Seal welding 
may be used, if desired. 

(d) Figure HG-307, sketch (d): C = 0.13 for integral 
flat circular heads when the dimension d does not exceed 
24 in. (610 mm), the ratio of thickness of the head to the 
dimension d is not less than 0.05 nor greater than 0.25, 
the head thickness t h is not less than the shell thickness t s , 
the inside corner radius is not less than 0.25t, and the 
construction is obtained by special techniques of upsetting 
and spinning the end of the shell, pipe, or header, such as 
employed in closing header ends. 

(e) Figure HG-307, sketches (e), (f), and (g): C = 0.33m 
but not less than 0.20 for circular plates, welded to the 
inside of a drum, pipe, or header, and otherwise meeting 
the requirements for the respective types of fusion welded 
boiler drums. If a value of m less than 1 is used in calculat- 
ing t, the shell thickness t s shall be maintained along a 
distance inwardly from the inside face of the head equal 
to at least 2j~dt s . The throat thickness of the fillet welds 
in sketches (e) and (f) shall be at least 0.7^. The size of 
the weld t w in sketch (g) shall be not less than two times 
the required thickness of a seamless shell nor less than 
1.25 times the nominal shell thickness but need not be 
greater than the head thickness; the weld shall be deposited 
in a welding groove with the root of the weld at the inner 
face of the head as shown in the figure. 

C = 0.33 for noncircular plates, welded to the inside 
of a drum, pipe, or header, and otherwise meeting the 
requirements for the respective types of fusion welded 
boiler drums. The throat thickness of the fillet welds in 
sketches (e) and (f) shall be at least 0.7^. The size of the 
weld t w in sketch (g) shall be not less than two times 



the required thickness of a seamless shell nor less than 
1.25 times the nominal shell thickness but need not be 
greater than the head thickness; the weld shall be deposited 
in a welding groove with the root of the weld at the inner 
face of the head as shown in the figure. 

(f) Figure HG-307, sketch (h): C = 0.33 for circular 
plates welded to the end of the shell when t s is at least 
\25t r and the beveled end of the shell is located at a 
distance no less than 2r nor less than 1.25f 5 from the outer 
face of the head. The width at the bottom of the welding 
groove shall be at least equal to the shell thickness but 
need not be over \ in. (6 mm). 

(g) Figure HG-307, sketch (i): C = 0.33m but not less 
than 0.20 for circular plates welded to the end of the drum, 
pipe, or header, when an inside weld with minimum throat 
thickness of 0.1 t s is used, and when the beveled end of the 
drum, pipe, or header is located at a distance not less than 
2t r nor less than 1.25^ from the outer face of the head. 
The width at the bottom of the welding groove shall be at 
least equal to t s , but need not be over % in. (6 mm). 

(h) Figure HG-307, sketches (j) and (k): C = 0.3 for 
circular and noncircular heads and covers bolted to the 
shell, flange, or side plate, as indicated in the figures. Note 
that Formula (2) or (5) shall be used because of the extra 
moment applied to the cover by the bolting. When the 
cover plate is grooved for a peripheral gasket, as shown 
in sketch (k), the net cover plate thickness under the groove 
or between the groove and the outer edge of the cover 
plate shall be not less than 



d ^jl.9WH c /Sd i 
for circular heads and covers, nor less than 



d J6WH G /SLd z 

for noncircular heads and covers. 

(i) Figure HG-307, sketches (m), (n), and (o): C = 0.3 
for a circular plate inserted into the end of a shell, pipe, 
or header, and held in place by a positive mechanical 
locking arrangement, and when all possible means of fail- 
ure either by shear, tension, compression, or radial defor- 
mation, including flaring, resulting from pressure and 
differential thermal expansion, are resisted with a factor 
of safety of at least five. Seal welding may be used, if 
desired. 

(j) Figure HG-307, sketch (p): C = 0.25 for circular 
and noncircular covers bolted with a full-face gasket to 
shells, flanges, or side plates. 

(k) Figure HG-307, sketch (q): C = 0.75 for circular 
plates screwed into the end of a shell, pipe, or header, 
having an inside diameter d not exceeding 12 in. (300 mm); 
or for heads having an integral flange screwed over the 
end of a shell, pipe, or header, having an inside diameter 
d not exceeding 12 in. (300 mm); and when the design of 



2007 SECTION IV 



FIG. HG-307 SOME ACCEPTABLE TYPES OF UNSTAYED FLAT HEADS AND COVERS 
(The Following Illustrations Are Diagrammatic Only; Other Designs That Meet the Requirements of 

HG-307 Will Be Acceptable.) 



■ Center of weld 

-Tangent 
[11 line 




C= 0.17 or 
C=0.10 

(a) 



f f min. = 2f c 




C=0.17 



■Center of weld 



t , h-Tangent 




(b) 



C = 0.20 



(0 



zhzzz 



-r= 0.25fmin. 



t, 



C=0.13 



(d) 



-0.7f. 




Q.lt s -y 



t w = 2f r min. nor less than 1.25f s 
but need not be greater than t 

\ Projection 

f s~l ^ |,,| / beyond weld 



\^\n Continuation 
^ of shell optional 



Sketches (e), (f), (g) Circular Covers, C = 0.33m: 
Noncircular Covers, C = 0.33 
(e) (f) 




is optional 
sj^jf — Bevel optional 
£fw I— 45deg max. 

Cmin. = 0.20 
(9) 



Min. t s but need 
not be over — 
V4 in. (6 mm) 

t e = 2t r but not . 
less than 1.25f s 

l 



J 



'///////, 



C = 0.33 
(h) 




Min. t s but need 
not be over 
V4 in. (6 mm) 

t e = 2t r but 
not less 
than 1.25f, 



C = 0.33m 
Cmin. = 0.20 




(i) 



■K^r 
C = 0.30 
[Use eq. (2) or (5)] 

(J) 




C = 0.30 
[Use eq. (2) or (5)] 

(k) 






Retaining ring 



C = 0.30 



(m) 





Threaded ring 



C = 0.30 



v y~ 



$ 



rz 



d 

1 

C = 0.75 

<q) 



■t 



(n) 




t 30 deg min. 

r's "V. 45 deg max. - 1 Seal weld^.n.75f min 



T 



1 



C - 0.33 



min. t-\ = t or t s 
whichever 
is greater 



lr) 




0.8f c min. 



• 



2007 SECTION IV 



• 



• 



the threaded joint against failure by shear, tension, com- 
pression, or radial deformation, including flaring, resulting 
from pressure and differential thermal expansion, is based 
on a factor of at least five. If a tapered pipe thread is used, 
the requirements of Table HG-370 shall also be met. Seal 
welding may be used, if desired. 

(I) Figure HG-307, sketch (r): C = 0.33 for circular 
plates having a dimension d not exceeding 18 in. (450 mm) 
inserted into the shell, pipe, or header, and welded as 
shown, and otherwise meeting the requirements for fusion 
welded boiler drums. The end of the shell, pipe, or header 
shall be crimped over at least 30 deg, but not more than 
45 deg. The crimping may be done cold only when this 
operation will not injure the metal. The throat of the weld 
shall be not less than the thickness of the flat head or the 
shell, pipe, or header, whichever is greater. 

(m) Figure HG-307, sketch (s): C = 0.33 for circular 
beveled plates having a diameter not exceeding 18 in. 
(450 mm), inserted into a shell, pipe, or header, the end 
of which is crimped over at least 30 deg, but not more 
than 45 deg, and when the undercutting for seating leaves 
at least 80% of the shell thickness. The beveling shall be 
not less than 75% of the head thickness. The crimping 
shall be done when the entire circumference of the cylinder 
is uniformly heated to the proper forging temperature for 
the material used. For this construction, the ratio t s ld shall 
be not less than the ratio P/S nor less than 0.05. The design 
pressure for this construction shall not exceed P = S/5d. 

Figure HG-307 is diagrammatic only. Other designs that 
meet the requirements of HG-307 will be acceptable. 



HG-309 SPHERICALLY DISHED COVERS 
(BOLTED HEADS) 

(a) Notation. The symbols used in the formulas of this 
paragraph are defined as follows: 

A = outside diameter of flange 
B = inside diameter of flange 
C = bolt circle diameter 
L = inside spherical or crown radius 
M = the total moment determined as in Section VIII, 
Division 1 , Appendix 2, 2-6, except that for heads 
of the type shown in Fig. HG-309, sketch (d), a 
moment H r h r (which may add or subtract) shall be 
included in addition to the moment H D h D where 
H D = axial component of the membrane load in 
the spherical segment acting at the inside 
of the flange ring 
= 0.1S5B 2 P 
h D = radial distance from the bolt circle to the 

inside of the flange ring 
H r = radial component of the membrane load in 
the spherical segment acting at the intersec- 
tion of the inside of the flange ring with the 



center line of the dished cover thickness 
H r = H D cot (3 X 
h r = lever arm of force H r about centroid of 

flange ring 

NOTE: Since H r h r in some cases will subtract from 
the total moment, the moment in the flange ring when 
the internal pressure is zero may be the determining 
loading for the flange design. 

P = design pressure 
r = inside knuckle radius 
S = maximum allowable stress value as given in 

Tables HF-300.1 and HF-300.2 
T = flange thickness 
t = minimum required thickness of head plate after 

forming 

HG-309.1 Heads Concave to Pressure. Circular spher- 
ically dished heads with bolting flanges, concave to the 
pressure and conforming to the several types illustrated in 
Fig. HG-309 shall be designed in accordance with the 
following formulas: 

(a) Heads of the Type Shown in Fig. HG-309, Sketch (a) 

(1) The thickness of the head t shall be determined 
by the appropriate formula in HG-305. 

(2) The head radius L or the knuckle radius r shall 
not exceed the limitations given in HG-305. 

(3) The flange shall comply at least with the require- 
ments of Section VIII, Division 1, Appendix 2, Fig. 2-4 
and shall be designed in accordance with the provisions 
of 2-1 through 2-7. (Within the range of ANSI B16.5, 
the flange facings and drillings should conform to those 
standards and the thickness specified therein shall be con- 
sidered as a minimum requirement.) 

(b) Heads of the Type Shown in Fig. HG-309, Sketch (b). 
(No joint efficiency factor is required.) 

(1) Head thickness 



t = 



5PL 

65 



(2) Flange thickness 
For ring gasket, 

For full-face gasket, 


T 






M 
SB 


A + B' 
A-B 




T = 0.6 / £ 


~B(A 


+ B)(C 
A-B 


'-*)] 



NOTE: The radial components of the membrane load in the spherical 
segment are assumed to be resisted by its flange. 

Within the range of ANSI B 16.5, the flange facings and drillings should 
conform to those standards, and the thickness specified herein shall be 
considered as a minimum requirement. 



2007 SECTION IV 



FIG. HG-309 SPHERICALLY DISHED STEEL PLATE COVERS WITH BOLTING FLANGES 



Edge of weld 
shall not overlap 
knuckle 




Gasket \ 

Loose Flange Type 



(a) 



Not less than 
2fand in no 
case less than 
1/2 in. 



k 

d 




Knuckle 
radius 



Gasket 
Integral Flange Type 



Ring 
gasket 
shown 



Preferably 




(c) 




Ring 
gasket 
shown 



Full penetration weld 



Use any suitable 
type of gasket 




Shown as welded 
smooth weld both 
sides 



( c) Heads of the Type Shown in Fig. HG-309, Sketch (c). 
(No joint efficiency factor is required.) 
(1) Head thickness 



t = 



5PL 
65 



(2) Flange thickness for ring gaskets shall be calcu- 
lated as follows: 

(a) For heads with round bolting holes, 



where 



T= Q + 



Q = 



l.S75M (C + B) 
SB(1C- 5B) 



PL 

45 



C + B 



1C-5B 



(I) 



(H) 



(b) For heads with bolting holes slotted through 
the edge of the head, 



T = Q + 



l.S15M (C + B) 
SB(3C- 5B) 



where 



^ PL 

Q = Ts 



C + B 



3C-B 



(HI) 



(IV) 



(3) Flange thickness for full face gaskets shall be 
calculated by the following formula: 



T = Q + 



q2 | 3BQ(C - B) 



(V) 



The value of Q in eq. (V) is calculated by eq. (II) for 
round bolting holes or by eq. (IV) for bolting holes slotted 
through the edge of the head. 

(4) The required flange thickness shall be T as calcu- 
lated in (2) or (3) above, but in no case less than the value 
of t calculated in (1) above. 

(d) Heads of the Type Shown in Fig. HG-309, Sketch (d). 
(No joint efficiency factor is required.) 

(1) Head thickness 



« 



t = 



5 PL 
65 



(2) Range thickness 

T = F+ y F 2 + J 
where 

PB y 4L 2 - B 2 



and 



F = 



J = 



85 (A - B) 



M \ A + B 
SB \A-B 



10 



2007 SECTION IV 



HG-312 CYLINDRICAL PARTS UNDER 
EXTERNAL PRESSURE 

HG-312.1 Plain Type Furnaces. Plain furnaces that 
are complete cylinders shall conform to the following: 

(a) The thickness of the furnace wall shall be not less 
than \ in. (6 mm). 

(b) The design temperature of the furnace shall be taken 
as 500°F (260°C). 

(c) Furnaces shall be rolled to a circle, with a maximum 
deviation from the true circle of not more than \ in. (6 mm). 

(d) The thickness of the furnace wall shall be deter- 
mined by the use of the rules of HG-312.3. External pres- 
sure charts for use in determining minimum requirements 
are given in Subpart 3 of Section II, Part D. Figure numbers 
in this Article are contained in that Subpart. The symbols 
defined as follows are used in the formulas of this para- 
graph: 

A = factor determined from Fig. G in Subpart 3 of 
Section II, Part D and used to enter the applicable 
material chart in Subpart 3 of Section II, Part D 

B = factor determined from the applicable material 
chart in Subpart 3 of Section II, Part D for maxi- 
mum design, metal temperature [see 
HG-312. 1(b)] 
D — outside diameter of furnace 

L = design length of plain furnace taken as the distance 
from center to center of weld attachment, in.; 
design length of ring reinforced furnace section, 
taken as the greatest center-to-center distance 
between any two adjacent stiffening rings; or the 
distance from the center of the first stiffening ring 
to the center of the furnace weld attachment, in. 
In case a flared-end assembly is used, the distance 
shall be measured to the point of tangency 
between the flare and the furnace and the adjacent 
stiffening ring. 

P = design pressure 

t = minimum required wall thickness of furnaces 

HG-312.2 Tubes. The wall thickness of tubes subject 
to external pressure shall conform to the following: 

(a) The minimum wall thickness shall be determined 
by use of the procedure outlined in HG-312.3. 

(b) The design temperature of tubes shall be the mean 
metal temperature as determined by the boiler Manufac- 
turer. 

(c) A minimum additional thickness of 0.04 in. (1 mm) 
shall be added as an allowance for rolling and structural 
stability. The additional 0.04 in. (1 mm) thickness is not 
required for tube strength welded to tubesheets, headers, 
or drums. 

HG-312.3 Procedure for Determining Wall Thick- 
ness of Plain Furnaces and Tubes. The required wall 



thickness of the furnace and tubes shall be not less than 

determined by the following procedure: 

Step 1 : Assume a value for t. Determine the ratio L/D 
and D /t. 

Step 2: Enter Fig. G in Subpart 3 of Section II, Part D 
at the value of L/D determined in Step 1 . For 
values of L/D greater than 50, enter the chart 
at a value of L/D = 50. For values of LfD 
less than 0.05, enter the chart at a value of L/ 
D = 0.05. 

Step 3: Move horizontally to the line for the value of 
D lt determined in Step 1. Interpolation may 
be made for intermediate values of D /t. From 
this point of intersection, move vertically down- 
ward to determine the value of factor A. 

Step 4: Using the value of A calculated in Step 3, enter 
the applicable material chart in Subpart 3 of 
Section II, Part D for the material under consid- 
eration. Move vertically to an intersection with 
the material/temperature line for the design tem- 
perature. 

Step 5: From the intersection obtained in Step 4, move 
horizontally to the right and read the value of 
factor B. 

Step 6: Using this value of B, calculate the value of the 
maximum allowable external working pressure 
P a using the following formula: 



Pn = 



B 



DJt 



Step 7: Compare P a with P. If P a is less than P, a greater 
value of t must be selected or a smaller value 
of L or some combination of both to increase 
P a so that it is equal to or greater than P. (An 
example is included in Appendix C.) 

HG-312.4 Ring Reinforced Type Furnace. Ring rein- 
forced furnaces as shown in Fig. HG-312.3 may be con- 
structed with completely circular stiffening rings provided 

(a) the stiffening ring is rectangular in cross section and 
is fabricated from one piece of plate, or from plate sections 
or bars provided full-penetration welds are used in assem- 
bling. 

(b) the stiffening ring after fabrication has a thickness 
of not less than \§ in. (8 mm) and not more than l3 / l6 
in. (21 mm) and in no case thicker than \\ times the 
furnace wall. 

(c) the ratio of height of the stiffening ring to its thick- 
ness (H r /T r ) is not over eight nor less than three. 

(d) the stiffening ring is attached to the furnace by a 
full penetration weld as shown in Fig. HG-312.3. 

(e) the thickness of the furnace wall is a minimum of 
\ in. (6 mm). 

(f) the design temperature of the furnace shall be taken 
as 500°F (260°C). 



11 



2007 SECTION IV 



FIG. HG-312.3 ACCEPTABLE TYPE OF RING 
REINFORCED FURNACE 



ir r ^ 



Alternate end assemblies 



Full penetration continuous 
weld both sides of rings 




i— i 



! f T ir^Rr° 



-4* L •+*- 



■*U L- 



-*...u 



(g) the boiler design permits replacement of the furnace. 
A flared or welded OG-ring may be accepted as meeting 
this requirement. (See Fig. HG-312.3.) 

(h) the thickness of the furnace wall or tube wall and the 
design of stiffening rings are determined by the procedure 
contained in Steps 1 through 7 of HG-312.3. L is as defined 
in HG-312.1. The symbols defined in HG-312.1 are used 
in the design formula. Steps 1 through 7 of HG-312.3 shall 
apply. 

(i) the required moment of inertia of a circumferential 
stiffening ring shall not be less than determined by the 
following formula: 



L = 



D}L \t + 'f\A 



14 



where 



A s = cross-sectional area of the stiffening ring, sq in 



(mm 2 ) 



= required moment of inertia of the stiffening ring 
about its neutral axis parallel to the axis of the 
furnace, in. 4 (mm 4 ) 

P, D , and t are as defined in HG-312.1. 

HG-312.5 Procedure for Determining Moment of 
Inertia of Stiffening Rings. The moment of inertia for a 
stiffening ring shall be determined by the following pro- 
cedure. 

Step 1: Assuming that the furnace has been designed 
and D , L, and t are known, select a rectangular 
member to be used for a stiffening ring and 



determine its area A s and its moment of inertia 
/. Then calculate B by the following formula: 



B = 



A s 

t + T 



where 

B is as defined in HG-312.1. 

P, D , t, A s , and L are defined above. 

Step 2: Enter the right-hand side of the applicable mate- 
rial chart in Subpart 3 of Section EL Part D for 
the material under consideration at the value of 
B determined in Step 1. 

Step 3: Follow horizontally to the material line. 

Step 4: Move down vertically to the bottom of the chart 
and read the value of A. 

Step 5: Compute the value of the required moment of 
inertia I s from the formula given above. 

Step 6: If the required I s is greater than the moment of 
inertia / for the section selected in Step 1, a new 
section with a larger moment of inertia must be 
selected and a new I s determined. If the required 
I s is smaller than / for the section selected by 
Step 1, that section should be satisfactory. (An 
example is included in Appendix C.) 

HG-312.6 Corrugated Furnaces. The design pressure 
of corrugated furnaces, such as the Leeds suspension bulb, 
Morison, Fox, Purves, or Brown, having plain portions at 
the ends not exceeding 9 in. (225 mm) in length shall be 
computed as follows: 



(U.S. Customary Units) 



(SI Units) 



P = Ct/D 



P = 6.89C(t/D) kPa 



where 
C = 



C = 



C = 



C = 



17,300 (119 000), a constant for Leeds furnaces, 
when corrugations are not more than 8 in. 
(200 mm) from center to center and not less than 
l\ in. (57 mm) deep 

15,600 (108 000), a constant for Morison fur- 
naces, when corrugations are not more than 8 in. 
(200 mm) from center to center and the radius of 
the outer corrugation is not more than one-half 
of the suspension curve 

14,000 (96 500), a constant for Fox furnaces, 
when corrugations are not more than 8 in. 
(200 mm) from center to center and not less than 
l/£ in. (38 mm) deep 

14,000 (96 500) a constant for Purves furnaces, 
when rib projections are not more than 9 in. 



12 



2007 SECTION IV 



(225 mm) from center to center and not less than 

1% in. (35 mm) deep 
C = 14,000 (96 500) a constant for Brown furnaces, 

when corrugations are not more than 9 in. 

(225 mm) from center to center and not less than 

1% in. (41 mm) deep 
D = mean diameter, in. (mm) 
P = design pressure, psi (kPa) 
t = thickness, in. (mm), not less than % 6 in. (8 mm) 

for Leeds, Morison, Fox, and Brown, and not less 

than 7 / x6 in. (1 1 mm) for Purves and other furnaces 

corrugated by sections not over 18 in. 

(450 mm) long 

(a) In calculating the mean diameter of the Morison 
furnace, the least inside diameter plus 2 in. (50 mm) may 
be taken as the mean diameter. 

(b) The longitudinal and circumferential joints shall be 
fusion welded of the double-welded butt type. 

(c) The thickness of a corrugated or ribbed furnace shall 
be ascertained by actual measurement by the furnace manu- 
facturer, by gaging the thickness of the corrugated portions. 
If a hole is drilled through the sheet to determine the 
thickness, the hole shall be not more than % in. (10 mm). 
When the furnace is installed, this hole shall be located in 
the bottom of the furnace and closed by a threaded plug. 
For the Brown and Purves furnaces, the hole shall be in 
the center of the second flat from the boiler front; for the 
Morison, Fox, and other similar types, in the center of the 
top corrugation, at least as far in as the fourth corrugation 
from the front end of the furnace. 

HG-312.7 Combination Type Furnaces. Combination 
type furnaces for external pressure may be constructed by 
combining a plain circular section and a corrugated section 
provided 

(a) each type of furnace is designed to be self-support- 
ing, requiring no support from the other furnace at their 
point of connection. 

(b) HG-312.1 and HG-312.3 shall be used for calculat- 
ing the design pressure of the plain section; in applying 
the length in the text, or L in the formulas, the length used 
shall always be twice the actual length of the plain section; 
the actual length of plain section is the distance measured 
from the center line of the head attachment weld to the 
center line of the full penetration weld joining the two 
sections. 

(c) the design pressure of the corrugated section shall 
be determined from HG-312.6. 

(d) the full penetration weld joining a plain self-support- 
ing section to a corrugated self-supporting section shall be 
located as shown in Fig. HG-312.6. 

HG-312.8 Semicircular Furnaces or Crown Sheets 
Subjected to External Pressure. Unstayed furnaces or 
crown sheets where the top portion is semicircular and the 



FIG. HG-312.6 CONNECTION BETWEEN PLAIN AND 
CORRUGATED FURNACE 



Max. 3 t or 1 1/2 in. (35 mm) 
(whichever is less) 




Point of tangency 



unstayed portion does not exceed 120 deg in arc shall 
conform to the following. 

(a) The thickness of the semicircular furnace or crown 
sheet shall be not less than % 6 in. (8 mm). 

(b) The design temperature of the semicircular furnace 
or crown sheet shall be taken as 500°F (260°C). 

(c) Semicircular portions of the furnace or crown sheet 
shall be rolled to practically a true circle, with a maximum 
deviation from the true circle of not more than \ in. (6 mm). 

(d) The allowable working pressure of the semicircular 
furnace or crown sheet shall be not more than 70% of P a 
as computed from the procedure outlined in HG-312.1 and 
HG-312.3 and using the applicable chart. 

(e) Bar Reinforcement 

(1) Bar reinforcement, when required to reduce the 
effective furnace length L, shall be computed using the 
formulas in HG-312.5 and HG-312.4. 

(2) Bar reinforcement shall be fabricated and installed 
as shown in Fig. HG-312.7. 

(3) Bar reinforcement, after fabrication, shall have a 
thickness of not less than ^ 6 in. (8 mm) and not more than 
Vis m - (21 mm) and in no case thicker than \\ times the 
wall section of the semicircular portion. 

(4) The ratio of height of the bar reinforcement to 
its thickness H r IT r shall be not more than eight nor less 
than three. 

(f) For unstayed furnaces or crown sheets, where the top 
portion is semicircular and the unstayed portion exceeds 
120 deg in arc, that portion exceeding the 120 deg arc 
shall be stayed as a flat plate in accordance with HG-340. 



13 



2007 SECTION IV 



FIG. HG-312.7 ACCEPTABLE TYPE OF SEMICIRCULAR FURNACE REINFORCEMENT 




Full penetration continuous weld- 
both sides of bar reinforcement 



-H 



J 



E. 



iL 



Bzal ' 




HG-320 OPENINGS IN BOILERS, GENERAL 
REQUIREMENTS 34 
HG-320. 1 Shape of Openings. 5 Openings in cylindri- 
cal, spherical, or conical portions of boilers or in formed 
heads shall preferably be circular, elliptical, or obround 6 
except as otherwise provided in HG-320.2. When the long 
dimension of an elliptical or obround opening exceeds 
twice the short dimension, the reinforcement across the 
short dimension shall be increased as necessary to provide 
against excessive distortion due to twisting moment. 

HG-320.2 Size of Openings. While openings in cylin- 
drical and spherical shells are not limited as to size provided 
they are adequately reinforced, the rules given herein for 



3 The rules governing openings as given in this Code are based on the 
stress intensification created by the existence of a hole in an otherwise 
symmetrical section. They are based on experience with vessels designed 
with a safety factor of five applied to the specified minimum tensile 
strength of the shell material. External loadings such as those due to 
thermal expansion or to unsupported weight of connecting piping have 
not been evaluated. These factors should be given attention in unusual 
designs or under conditions of cyclic loading. 

4 Typical examples of the application of these rules are given in 
Appendix D. 

5 The opening made by a pipe or a circular nozzle, the axis of which 
is not perpendicular to the boiler wall or head, may be considered an 
elliptical opening for design purposes. 

6 An obround opening is one that is formed by two parallel sides and 
semicircular ends. 



reinforcement are intended to apply to openings not 
exceeding the following dimensions: 

(a) for boilers 60 in. (1 500 mm) in diameter and less: 
one-half the boiler diameter but not over 20 in. (500 mm). 

(b) for boilers over 60 in. (1 500 mm) in diameter: one- 
third the boiler diameter, but not over 40 in. (1 000 mm). 

(c) larger openings should be given special attention 
and may be provided with reinforcement in any suitable 
manner that complies with the intent of the Code rules. It 
is recommended that the reinforcement provided be distrib- 
uted close to the opening. (A provision of about two-thirds 
of the required reinforcement within a distance of one- 
fourth of the nozzle diameter on each side of the finished 
opening is suggested.) Special consideration should be 
given to the fabrication details used and the inspection 
employed on critical openings; reinforcement often may 
be advantageously obtained by use of a thicker shell plate 
for a boiler course or inserted locally around the openings; 
welds may be ground to concave contour and the inside 
corners of the opening rounded to a generous radius to 
reduce stress concentrations. Appropriate proof testing may 
be advisable in extreme cases of large openings 
approaching full boiler diameter, openings of unusual 
shape, etc. 



14 



2007 SECTION IV 



HG-320.3 Strength and Design of Finished Openings 

(a) All references to dimensions in this and succeeding 
paragraphs apply to the finished construction after adjust- 
ment has been made for any material added as corrosion 
or other allowance. For design purposes, no metal added 
as corrosion or other allowance may be considered as rein- 
forcement. Reinforcement shall be provided to satisfy the 
requirements of HG-321 for all openings except as other- 
wise provided in (b), (c), and (d) below. 

(b) Openings in a definite pattern, such as tube holes, 
may be designed in accordance with the rules for ligaments 
in HG-350 provided the diameter of the largest hole in 
the group does not exceed that permitted by the chart in 
Fig. HG-320. 

The symbols given in Fig. HG-320 are defined as 
follows: 

D = outer diameter of the shell, in. (mm) 

d = maximum allowable diameter of opening, in. 

(mm) 
K = PDIlSt 
P = design pressure 
S = maximum allowable stress value taken from 

Table HF-300 
t = nominal thickness of the shell, in. (mm) 

(c) No calculations need be made to determine the avail- 
ability of reinforcement for single openings in boilers not 
subject to rapid fluctuations in pressure or temperature and 
in which the outside diameter of the opening does not 
exceed one-fourth of the inside diameter of the boiler, 
provided the diameter of the finished opening as defined 
in HG-321. 2 does not exceed the following sizes: 

(1) NPS 2 (DN 50) for welded connections in boiler 
walls over \ in. (10 mm) thick and for all threaded, studded, 
or expanded connections 

(2) NPS 3 (DN 80) for welded connections in boiler 
walls \ in. (10 mm) thick and under 

(d) No calculations need be made to demonstrate com- 
pliance with HG-321 for single openings not covered in 
HG-320.3(c) when either the diameter of the opening in 
the shell or header does not exceed that permitted in 
Fig. HG-320 or the calculated K value is less than 50%. 
The maximum diameter of single openings not required to 
demonstrate compliance with HG-321 may also be calcu- 
lated using the following equation: 

(U.S. Customary Units) 

d = 2.75 [Dt (1 -K)] m 
(SI Units) 

d = 8.08 [Dt(\ -K)] m 

Nomenclature for the above equation is given in 
HG-320.3(b). Three significant figures shall be employed 
for the variables in the equation and in the resulting value 



of d. Additional significant figures are permitted but not 
required. Use of the equation beyond the range of the 
abscissa and ordinate shown in Fig. HG-320 is prohibited. 
K as used in the equation is limited to 0.990. 



HG-321 REINFORCEMENT REQUIRED FOR 
OPENINGS IN SHELLS AND 
FORMED HEADS 

HG-321. 1 General. The rules in this subparagraph 
apply to all openings other than openings in a definite 
pattern covered by HG-320. 3(b), openings covered by 
HG-320.3(c) and HG-320.3(d), flanged-in openings in 
formed heads covered by HG-323, and openings in flat 
heads covered by HG-325. 

Reinforcement shall be provided in such amount and 
distribution that the requirements for area of reinforcement 
are satisfied for all planes through the center of the opening 
and normal to the boiler surface. For a circular opening in 
a cylindrical shell, the plane containing the axis of the 
shell is the plane of greatest loading due to pressure. 

HG-321.2 Design for Internal Pressure. The total 
cross-sectional area of reinforcement A required in any 
given plane for a boiler under internal pressure shall be 
not less than 



A = dt r F + 2t n t r F (1 -f rl ) 



where 



d = the diameter in the given plane of the finished 
opening (as depicted in Fig. HG-326.1) 

F = a correction factor that compensates for the varia- 
tion in pressure stresses on different planes with 
respect to the axis of a vessel. A value of 1.00 
shall be used for all configurations except that 
Fig. HG-321 may be used for integrally reinforced 
openings in cylindrical shells. 

t r = the required thickness of a seamless shell or head 
computed by the rules of the Code for the desig- 
nated pressure except that 

(a) when the opening and its reinforcement are 
in a torispherical head and are entirely within the 
spherical portion, t r is the thickness required for 
a seamless hemispherical head of the same radius 
as that of the spherical portion 

(b) when the opening is in a cone, t r is the 
thickness required for a seamless cone of diameter 
D measured where the nozzle axis pierces the 
inside wall of the cone 

(c) when the opening and its reinforcement are 
in an ellipsoidal head and are located entirely 
within a circle the center of which coincides with 
the center of the head and the diameter of which 
is equal to 80% of the shell diameter, t r is the 



15 



2007 SECTION IV 



FIG. HG-320 CHART SHOWING LIMITS OF SIZES OF OPENINGS WITH INHERENT 

COMPENSATION IN CYLINDRICAL SHELLS 

(Maximum Permissible Diameter of Opening Is 8 in.) 



1 




















































I I I 
























































/C=50% 
























































6 b 


























































































































— ; 






























































t3 






























































£ 5 




















































/C=75% 






























































Q. 






























































o 






























































o 
•- 4 


























































































































E 


























































































































Q 
E 3 
















































































































K - 3O70 


F 






























































'x 






























































^ ? 
















































































































./C=99% 
and over 


















































































































1 




/ 


















































































































































































































































n 































































10 15 20 

Drum Diameter xThickness (Dt), in. 2 



25 



30 



















< 


so 


% 
















i* 


% 








«o°/< 


> 








IK 




n*W 


D 
















8 














K- 


















"j" 








l£'" M 








































A 


*/ 


^ 


VJ, 


^ 


'/ 


£, 


>« 


'• 


£ 
































































/ 


/ 


'' 














































































j 


> 


> 






























































K = 90°/ 


'o 


c 7 






A 


>j 


', 


', 












































































/, 


' 


/ 










































































^_,^ 




^ 


/ 


/, 


/ 










































































T3 




Z 


/ 




/ 










































































o) 6 




/ 






A 


















































































rt 
































































7C = 95^ 


4 


c 




















































































u 




















































































O 5 






































































































































































O 






V 


'/, 












































































<u 




Y* 


y 














































































03 A 

F 




V 


/, 


















































































v. 












































































CO 




Y 






































































K=99% 


Q 












































































^3 
































































































































































F 




















































































'x 




















































































^ 2 














































































































































































































































































































































1 





















































































25 



50 



75 



100 



125 150 175 200 

and over 
Drum Diameter xThickness {Dt), in. 2 



16 



2007 SECTION IV 



FIG. HG-321 CHART FOR DETERMINING 
VALUES OF F 



1.00 

0.95 
0.90 
0.85 

0.80 

U. 
o 
» 0.75 

"5 
> 

0.70 
0.65 
0.60 
0.55 
0.50 



10 20 30 40 50 60 70 80 
Angle of plane with longitudinal axis, deg. 



90 



thickness required for a sphere of radius K\D 
where D is the shell diameter and K\ is given by 
Table HG-321 



HG-323 FLANGED-IN OPENINGS IN 
FORMED HEADS 

HG-323. 1 Reinforcement Requirements. Flanged-in 
openings in torispherical, ellipsoidal, and hemispherical 
heads shall be provided with reinforcement in accordance 
with HG-321, except for heads that meet the requirements 
in HG-323.2, HG-323.3, and HG-323.4. 

HG-323.2 Restrictions on Location. The flanged-in 
opening and its reinforcement shall be entirely within the 
spherical portion of torispherical heads, and within a circle 
the center of which coincides with the center of the head 
and the diameter of which equals 80% of the shell diameter 
for ellipsoidal and hemispherical heads. The center line of 
the opening shall not be closer to the above boundary circle 
than the diameter of the opening. 



HG-323.3 Minimum Thickness Requirements of 
Flanged-in Openings 

(a) For flanged-in openings that do not exceed 6 in. 
(150 mm) in any dimension and for flanged-in openings 
of any dimension that are stayed by an attached flue, the 
thickness of the head shall not be less than that required 
by HG-305 for a blank head, nor less than that required 
by HG-305 for torispherical heads. 

(b) For unstayed flanged-in openings that exceed 6 in. 
(150 mm) in any inside dimension, the head thickness shall 
be increased 15% but not less than \ in. (3 mm) greater 
than that required by (a) above. 

HG-323.4 Minimum Flange Depth. The minimum 
depth of flange of a flanged-in opening, when not stayed 
by an attached flue, shall equal 2>t or (t + 3) in., whichever 
is less, where t is the required head thickness. The depth 
of flange shall be determined by placing a straightedge 
across the outside of the opening along the major axis and 
measuring from the straightedge to the edge of the flanged 
opening. 

HG-323.5 Minimum Gasket Bearing Surface. The 

minimum width of bearing surface for a gasket on a 
flanged-in manhole opening shall be x \ 6 in. (17 mm). 



HG-325 REINFORCEMENT REQUIRED FOR 
OPENINGS IN FLAT HEADS 

HG-325.1 General. The rules in this paragraph apply 
to all openings other than small openings covered by 
HG-320.3(c). 

HG-325.2 Specific Requirements. Flat heads that have 
an opening with a diameter that does not exceed one-half 
of the head diameter or shortest span, as defined in HG-307, 
shall have a total cross-sectional area of reinforcement not 
less than that given by the formula: 



A = 0.5dt 



where 



d = diameter of the finished opening 
t = minimum required thickness of plate 

As an alternative, the thickness of flat heads may be 
increased to provide the necessary opening reinforcement 
as follows: 

(a) in Formula (1) or (3) of HG-307 by using 2C or 
0.75 in place of C, whichever is less. 

(b) in Formula (2) or (5) of HG-307 by doubling the 
quantity under the square root sign. Except for the types 
of construction shown in Fig. HG-307, sketches (j) and 
(k), the value of 2C to be used in the formulas need not 
exceed 0.75. 



17 



2007 SECTION IV 



FIG. HG-326.1 SOME REPRESENTATIVE CONFIGURATIONS DESCRIBING THE REINFORCEMENT DIMENSION, t e 

AND THE FINISHED OPENING DIMENSION, d 



1 — O" 



2 



f„ = 



(a-1) 






(a -2) 



(b) 





tn-*- 




^ 


'' y. 






jn 


n ; - 






/\ 




/A < 


\'i 






/ ' 


j 


( 


, $ 






M 




i 


I 








(0 





(a -3) 



30 deg. min. . 

60 deg. ^/V 



u 



*/ 



(d) 



Less than 30 deg. 



-£ 



i/ 



E 



60 deg. 
lei 



1 



^- f 60 deg 



<* -d 



zi 



(f) 





45 deg. max. 
30 deg. max. _ 



U 

3 /4 in. (19 mm) R min. - ^ 



lil 



18 



2007 SECTION IV 



TABLE HG-321 

VALUES OF SPHERICAL RADIUS FACTOR Ai 

(Equivalent Spherical Radius = K\ D; D/2h = axis ratio. 

Interpolation Permitted for Intermediate Values.) 



Dllh 




3.0 


2.8 


2.6 


2.4 


2.2 


Ki 




1.36 


1.27 


1.18 


1.08 


0.99 


Dl2h 


2.0 


1.8 


1.6 


1.4 


1.2 


1.0 


Ki 


0.90 


0.81 


0.73 


0.65 


0.57 


0.50 



GENERAL NOTES: 

(a) D = inside length of major axis, in. (mm). 

(b) d = inside depth of ellipsoidal head measured from the tangent 
line, in. (mm). 



HG-326 LIMITS OF METAL AVAILABLE 
FOR REINFORCEMENT 
HG-326.1 Designation of Limits of Reinforcement. 

The boundaries of the cross-sectional area in any plane 
normal to the boiler shell and passing through the center 
of the opening within which area metal must be located 
in order to have value as reinforcement are designated as 
the limits of reinforcement for that plane. 

HG-326.2 Limits of Reinforcement Parallel to Boiler 
Shell. The limits of reinforcement, measured parallel to 
the boiler shell, shall be at a distance, on each side of the 
axis of the opening, equal to the greater of the following: 

(a) the diameter of the finished opening 

( b) the radius of the finished opening plus the thickness 
of the boiler shell, plus the thickness of the nozzle wall 

HG-326.3 Limits of Reinforcement Normal to Boiler 
Shell. The limits of reinforcement, measured normal to the 
boiler shell, shall conform to the contour of the surface at 
a distance from each surface equal to the smaller of the 
following: 

(a) 2/£ times the nominal shell thickness 

(b) 2 l / 2 times the nozzle wall thickness, plus the thick- 
ness of any added reinforcement, exclusive of weld metal 
on the side of the shell under consideration 

HG-326.4 Use of Excess Boiler Shell and Other 
Thicknesses. Metal that may be included as contributing 
to the area of reinforcement required by HG-321 shall lie 
within the limits of reinforcement specified in HG-326.2 
and HG-326.3 and shall be limited as set forth in (b), (c), 
(d), and (e) below (see Fig. HG-326.2). 

(a) Notation. The symbols used in this paragraph are 
defined as follows: 

Ax = area in excess thickness in the boiler shell avail- 
able for reinforcement 

A 2 = area in excess thickness in the nozzle wall avail- 
able for reinforcement 

D p = outside diameter of reinforcing element (actual 
size of reinforcing element may exceed the limits 
of available reinforcement established by 



HG-326; however, credit cannot be taken for any 
material outside these limits) 
d = diameter in the plane under consideration of the 
finished opening (see HG-321. 2 and 
Fig. HG-326.1) 
Ei = when an opening is in the solid plate or when the 
opening passes through a circumferential joint in 
a shell or cone (exclusive of head-to-shell joints) 
= the joint efficiency obtained when any part of the 
opening passes through any other welded joint 
F = factor F from HG-321. 2 and Fig. HG-321 
f r = strength reduction factor, not greater than 1 .0 (see 
HG-327.1) 

fr\ = S n /S v for nozzle inserted through the ves- 
sel wall 
f r i = 1.0 for nozzle wall abutting the vessel wall 
[see Fig. HG-326.1 sketches (a-1), (a-2), 
and (a-3)] 

frl = S n /S v 

fa = (lesser of S n or S p )/S v 

JrA = "p/iS v 

h = distance nozzle projects beyond the inner surface 
of the vessel wall (extension of the nozzle beyond 
the inside surface of the vessel wall is not limited; 
however, for reinforcement calculations the 
dimension shall not exceed the smaller of 2.5 t 
or 2.5 t n without a reinforcing element and the 
smaller of 2.5 t or 2.5 t n + t e with a reinforcing 
element or integral compensation) 

R n = inside radius of the nozzle under consideration 
S = maximum allowable stress value taken from 
Table HF-300 

S n = allowable stress in nozzle (see S above) 

S p — allowable stress in reinforcing element (plate) (see 
S above) 

S v = allowable stress in vessel (see S above) 
t = nominal thickness of the boiler shell 
t e = thickness of attached reinforcing pad or height of 
the largest 60 deg right triangle supported by the 
vessel and nozzle outside diameter projected sur- 
faces and lying completely within the area of inte- 
gral reinforcement (see Fig. HG-326.1) 

t n = nominal thickness of nozzle wall 
t r = required thickness of a seamless shell or head as 
defined in HG-321 

t m = required thickness of a seamless nozzle wall 

(b) Metal in the Boiler Shell Over and Above the Thick- 
ness Required to Resist Pressure. The area of the boiler 
shell available as reinforcement that shall be used is the 
larger of the values of A! given by the formulas in 
Fig. HG-326.2. 

(c) Metal in the nozzle wall over and above the thickness 
required to resist pressure in that part of a nozzle wall 



19 



2007 SECTION IV 



FIG. HG-326.2 NOMENCLATURE AND FORMULAS FOR REINFORCED OPENINGS 

(This Figure Illustrates a Common Nozzle Configuration and Is Not Intended to Prohibit 

Other Configurations Permitted by the Code.) 



Includes consideration of 
these areas if S n /S v < 1.0 
(both sides of (£) 



2.5for2.5f n + f ( 
Use smaller value 




2.5for2.5f n 
Use smaller value 



Use larger value 
For nozzle wall inserted through the vessel wa 



EZZZZZZ] 



= A 

= Ay 



Without Reinforcing Element 

= dt r F+2t n t r FC\-f r y) 

= d(Eyt- Ft r ) - 2f n (Eyt- Ft r ) (1 - f n ) 

2(f + f n ) (Eyt- Ft r ) - 2f n (Eyt- Ft r ) (1 - f n ) 
= 5(f n -f rn )f r2 r 

5(t n -t m )f r2 t n 



L^ = A 2 

KXXX1 = A 3 2f n f r2 h 

j/\ IK. = An = outward nozzle weld = (leg) 2 f r 2 
■^l r7 = ^43 = inward nozzle weld = (leg) 2 f r 2 

If Ay + A 2 + A% + /A41 + A42 > A 
If A-\ + A 2 + A$ + An + A43 < A 



Use larger value 

For nozzle wall abutting the vessel wall 

Area required 

Area available in shell; use larger value 

Area available in nozzle projecting 
outward; use smaller value 

Area available in inward nozzle 

Area available in outward weld 
Area available in inward weld 

Opening is adequately reinforced 

Opening is not adequately reinforced so 
reinforcing elements must be added 
and/or thickness must be increased 



With Reinforcing Element Added 



A 
Ay 



A 2 
A3 



Area required 
Area available 

Area available in nozzle projecting 
outward; use smaller area 

Area available in inward nozzle 
Area available in outward weld 
Area available in outer weld 
Area available in inward weld 

Area available in element 

If Ay + A 2 + A3 + A41 + A42 + A43 + A5 > A Opening is adequately reinforced 

NOTE: 

(1) This formula is applicable for a rectangular cross-sectional element that falls within the limits of reinforcement. 



= same as A above 

= same as Ay above 

= 5(t n -t rn )f r2 t 

2(t n -t rn )(2.5t n +t e )f r2 

= same as A3 above 
^ ^ = A41 = outward nozzle weld = (leg) 2 f r 3 
/] fK = A42 = outer element weld = (leg) 2 f f 4 
^ ^ = A43 = inward nozzle weld = (leg) 2 f r 2 

= A 5 = (D p -d-2t n )t e f rA [Note (1)] 



20 



2007 SECTION IV 



extending outside the boiler shell. The maximum area in 
the nozzle wall available as reinforcement in the portion 
extending outside the boiler shell is the smaller of the 
values of A 2 given by the formulas in Fig. HG-326.2. All 
metal in the nozzle wall extending inside the boiler shell, 
designated as A 3 in Fig. HG-326.2, may be included. No 
allowance shall be taken for the fact that a differential 
pressure on an inwardly extending nozzle may cause oppos- 
ing stress to that of the stress in the shell around the 
opening. 

(d) Metal in the attachment welds, designated as A 4 in 
Fig. HG-326.2, may be included. 

(e) Metal added as reinforcement, designated as A 5 in 
Fig. HG-326.2, may be included. 



HG-327 STRENGTH OF REINFORCEMENT 

HG-327.1 Strength of Nozzle and Added Material. 

Material in the nozzle wall and added material used for 
reinforcement shall preferably be the same as that of the 
boiler shell, but if material with a lower allowable stress 
value is used, the area provided by such material shall be 
increased in proportion to the inverse ratio of the allowable 
stress values of the reinforcement and the boiler shell mate- 
rial. No advantage may be taken of the increased strength 
of reinforcement material having a higher allowable stress 
value than the material of the boiler shell. Deposited weld 
metal outside of either the boiler shell or any reinforcing 
pad used as reinforcement shall be credited with an allow- 
able stress value equivalent to the weaker of the materials 
connected by the weld. Boiler-to-nozzle or pad-to-nozzle 
attachment weld metal within the pad may be credited with 
a stress value equal to that of the boiler shell or pad, 
respectively. 

HG-327.2 Strength of Attachment Material. On each 
side of the plane defined in HG-326.1, the strength of the 
attachment joining the boiler shell and reinforcement or 
any two parts of the attached reinforcement shall be at 
least equal to the smaller of 

(a) the strength in tension of the cross section of the 
element of reinforcement being considered. 

(b) the strength in tension of the area defined in HG-321 
less the strength in tension of the reinforcement area that 
is integral in the boiler shell as permitted by HG-326.4. 

(c) the strength of the attachment joint shall be consid- 
ered for its entire length on each side of the plane of the 
area of reinforcement defined in HG-326.1. For obround 
openings, consideration shall also be given to the strength 
of the attachment joint on one side of the plane transverse 
to the parallel sides of the opening that passes through the 
center of the semicircular end of the opening. 



HG-328 REINFORCEMENT FOR MULTIPLE 
OPENINGS 

HG-328.1 When Limits of Reinforcement Overlap. 

When any two adjacent openings are spaced at less than 
two times their average diameter so that their limits of 
reinforcement overlap, the two openings (or similarly for 
any larger group of openings) shall be provided with rein- 
forcement in accordance with HG-321 with a combined 
reinforcement that has a strength equal to the combined 
strength of the reinforcement that would be required for 
the separate openings. No portion of the cross section shall 
be considered as applying to more than one opening or be 
evaluated more than once in a combined area. 

HG-328.2 Combined Reinforcement for Multiple 
Openings. When more than two adjacent openings are to 
be provided with a combined reinforcement, the minimum 
distance between centers of any two of these openings 
shall preferably be at least 1 \ times their average diameter, 
and the area of reinforcement between them shall be at 
least equal to 50% of the total required for these two 
openings. 

(a) Two adjacent openings as considered under 
HG-328.2 shall have a distance between centers not less 
than \% times their average diameter. 

(b) In lieu of providing reinforcement for individual 
openings, reinforcement may be provided for any number 
of closely spaced adjacent openings, in any arrangement, 
by providing reinforcement for an assumed opening of a 
diameter enclosing all such openings. 

(c) When a group of openings is provided with rein- 
forcement by a thicker section butt welded into the shell 
or head, the edges of the inserted section shall be tapered 
as prescribed in HW-701.1. 

HG-328.3 When Reinforcing Each of a Series of 
Openings Is Impractical. When there is a series of tube 
openings in a boiler and it is impractical to reinforce each 
opening, the construction will be acceptable provided the 
ligaments between openings are calculated by the rules 
given in HG-350. 



HG-330 INSPECTION AND ACCESS 
OPENINGS 

HG-330.1 General Inspection Openings 

(a) All boilers shall be provided with suitable manhole 
openings and handhole or washout plug openings to permit 
inspection and removal of accumulated sediment. 

(b) Electric boilers of a design employing a removable 
cover that will permit access for inspection and cleaning 
and having an internal gross volume (exclusive of casing 
and insulation) of not more than 5 ft 3 (0.14 m 3 ) need not 
be fitted with washout or inspection openings. 



21 



2007 SECTION IV 



Electric boilers equipped with immersion type resistance 
elements not provided with a manhole shall have an inspec- 
tion opening or handhole located in the lower portion of 
the shell or head. The inspection opening shall not be 
smaller than NPS 3 (DN 80). In addition, electric boilers 
designed for steam service shall have an inspection opening 
or manhole at or near the normal waterline. 

(c) Furnaces of internally fired boilers shall be provided 
with access doors as required by HG-330.5. 

HG-330.2 Manholes. A manhole shall be placed in the 
front head below the tubes of a horizontal-return tubular 
boiler 60 in. (1 500 mm) or over in diameter. There shall 
be a manhole in the upper part of the shell, or in the head 
of a firetube boiler over 60 in. (1500 mm) in diameter, 
except in a vertical firetube boiler. 

HG-330.3 Size of Manholes and Gasket Surfaces 

(a) An elliptical manhole opening shall not be less than 
12 in. X 16 in. (300 mm X 400 mm) in size. 

(b) A circular manhole opening shall not be less than 
15 in. (380 mm) in diameter. 

(c) The minimum width of bearing surface for a gasket 
on a manhole opening shall be l ){ 6 in. (17 mm). 

(d) No gasket for use on a manhole or handhole of any 
boiler shall have a thickness greater than % in. (3 mm) 
when compressed. 

HG-330.4 Handholes and Washout Plugs 

(a) Boilers of the locomotive or firebox type, except 
those set in brick or otherwise so constructed as to render 
such openings inaccessible, shall have one handhole or 
washout plug near each corner in the lower part of the 
waterleg and at least one opening near the line of the crown 
sheet. In addition, boilers designed for steam service shall 
have at least one inspection opening above the top row of 
tubes. This inspection opening shall be a minimum of NPS 
3 (DN 80) or a handhole as specified in (f) below and used 
solely for inspection purposes. 

(b) A boiler of the scotch type shall have a handhole 
or washout plug in the front head below or on each side 
of the furnace or on each side of the shell near the front 
head, a handhole or washout plug in the bottom of the 
shell, an opening to inspect the top of the furnace and 
an inspection opening above the top row of tubes. This 
inspection opening shall be a minimum of NPS 3 (DN 80) 
or a handhole as specified in (f) below and used solely for 
inspection purposes. Scotch marine boilers (wet-back type) 
shall also have an opening for inspection of the water space 
at the rear of the combustion chamber. 

(c) Vertical firetube or similar type boilers having gross 
internal volume (exclusive of casing and insulation) more 
than 5 ft 3 (0.14 m 3 ) shall have at least three handholes or 
washout plugs in the lower part of the waterleg and at least 
two handholes or washout plugs near the line of the lower 
tubesheet. Such boilers having gross internal volume not 



over 5 ft 3 (0.14 m 3 ) shall have at least two washout open- 
ings in the lower part of the waterleg and at least one 
washout opening near the line of the lower tubesheet. In 
addition, boilers designed for steam service shall have at 
least one inspection opening above the lowest permissible 
water level. This inspection opening shall be a minimum 
of NPS 3 (DN 80) or a handhole as specified in ( f ) below 
and used solely for inspection purposes. 

(d) Washout plugs shall be not smaller than NPS \\ 
(DN 40) for boilers having gross internal volume more 
than 5 ft 3 (0.14 m 3 ). Washout plugs shall be not smaller 
than NPS 1 (DN 25) for boilers having gross internal 
volume not more than 5 ft 3 (0.14 m 3 ). 

(e) Washout openings may be used for return pipe con- 
nections and the washout plug placed in a tee so that the 
plug is directly opposite and as close as possible to the 
opening in the boiler. 

(f) A handhole opening shall not be less than 2% in. x 
3/£ in. (70 mm x 89 mm) but it is recommended that, 
where possible, larger sizes be used. 

HG-330.5 Access Doors 

(a) A fire door or other access not less than 1 1 in. x 
15 in. (280 mm x 380 mm) or 10 in. x 16 in. (250 mm 
X 400 mm) or 15 in. (381 mm) in diameter, shall be 
provided for the furnace of an internally fired boiler in that 
the least furnace dimension is 28 in. (711 mm) or over. 
The minimum size of access door used in a boiler setting 
shall be 12 in. X 16 in. (300 mm x 400 mm), or equivalent 
area, the least dimension being 1 1 in. (280 mm). 

(b) Fuel Burning Equipment. Fuel burning equipment 
may be installed in the fire door opening provided the 
cover plate can be unbolted or unlatched to give full-size 
access to the furnace through the fire door opening. 



HG-340 STAYED SURFACES 
HG-340.1 Required Thickness and Design Pressure 

(a) The required thickness and design pressure for 
stayed flat plates and those parts that, by these rules, require 
staying, as flat plates with stays or staybolts of uniform 
cross section that are symmetrically spaced, shall be calcu- 
lated by the following formulas: 



t = P 7 p/sc 



P = t 2 SC/p 2 



(1) 

(2) 



where 



C = 2.7 for stays welded to plates or for stays screwed 
through plates not over 7{ 6 in. (11 mm) in thick- 
ness, with ends riveted over 

C = 2.8 for stays welded to plates or for stays screwed 
through plates over 7i 6 in. (11 mm) in thickness, 
with ends riveted over 



22 



2007 SECTION IV 



FIG. HG-340.1 PITCH OF STAYBOLTS ADJACENT TO 
UPPER CORNERS OF FIREBOXES 



FIG. HG-340.2 ACCEPTABLE PROPORTIONS FOR 
ENDS OF THROUGH-STAYS 





li 



Max. r = p as calculated by 

HG-340.5 
Min. /■ = 3 f 

If the radius "r" in Fig. 
HG-340.1 exceeds the 
pitch, the curved plate 
shall be stayed as a flat 
plate in accordance with 
HG-340. 



Not less than 272 
diameters of bolt as 
measured on the out- 
side of the threaded 
portion, but must be 
0.4 pitch of stays 
if C=4.0 



Not less than 1/2 f if 
C= 3.5 or less, and not 
less than f if C = 4.0 




C = 3.1 for stays screwed through plates and fitted 
with single nuts outside of plate, or with inside 
and outside nuts, omitting washers 

C = 3.5 for stays with heads not less than 1.3 times 
the diameter of the stays screwed through plates, 
or made a taper fit and having the heads formed 
on the stays before installing them and not riveted 
over, said heads being made to have a true bearing 
on the plate 

C = 4.0 for stays fitted with inside and outside nuts and 
outside washers where the diameter of washers is 
not less than OAp and thickness not less than t 

P = design pressure 

p = maximum pitch measured between straight lines 
passing through the centers of the stays in the 
different rows, which lines may be horizontal, 
vertical, or inclined 

r = radius of firebox corner 

S = maximum allowable stress value given in Tables 
HF-300.1 and HF-300.2 

t = required thickness of plate 

(b) When two flat stayed surfaces intersect at an angle 
as shown in Fig. HG-340.1, the pitch from the staybolt 
nearest to the intersection to the point of tangency of the 
corner curve with the plate shall be 



P = 



90/ 



CS 



where yS is the angle shown in Fig. HG-340. 1 . 

(c) When two plates are connected by stays and only 
one of these plates requires staying, the value of C shall 
be governed by the thickness of the plate requiring staying. 

HG-340.2 Proportions of Through-Stays With 
Washers. Acceptable proportions for the ends of through- 
stays with washers are indicated in Fig. HG-340.2. 



FIG. HG-340.3 EXAMPLES OF ACCEPTABLE CORNER 
WELDS FOR PRESSURES NOT OVER 30 psi 




HG-340.3 Maximum Pitch of Stays. The maximum 
pitch shall be 8^ in. (216 mm) except that for welded-in 
stays the pitch may be greater provided it does not exceed 
15 times the diameter of the stay. 

HG-340.4 Unsymmetrical Staying. Where the staying 
of shells is unsymmetrical by reason of the construction, 
it is permissible to consider the load carried by each stay 
as that on the area calculated by taking the distance from 
the center of the spacing on one side of the stay to the 
center of the spacing on the other side. 

HG-340.5 Stay Distance to Corner Joints, Welded 
Joints, and Flanges 

(a) In the construction of a heating boiler designed for 
not over 30 psi (200 kPa) and having welded joints, the 
allowable distance from a corner welded joint to the nearest 
row of stays may be a full pitch as provided by the formula 
in HG-340.1. A welded joint in a fiat surface shall be 
between two rows of stays that are not over one pitch apart 
except that the type of joint shown in Fig. HG-340.3 shall 
have a row of stays not more than one pitch from the weld. 

(b) In the construction of heating boilers to be designed 
for water pressures above 30 psi (200 kPa), corner joints 
shall comply with the requirements of HW-701.3. 



23 



2007 SECTION IV 



(c) When the edge of a flat stayed plate is flanged, the 
distance from the center of the outermost stays to the inside 
of the supporting flange shall not be greater than the pitch 
of the stays plus the inside radius of the flange. 

HG-340.6 Allowable Pitch of Stays. The allowable 
pitch, in inches, for stays as given in Table HG-340 may 
be used in place of the pitch calculated under HG-340. 1 
when the allowable stress of the steel is 1 1,000 psi (76 MPa) 
or greater. 



HG-341 STAYBOLTS 

HG-341.1 Threaded Staybolts. The ends of staybolts 
extending through the plate shall extend beyond the plate 
not less than two threads when installed, after which they 
shall be riveted over or upset by an equivalent process 
without excessive scoring of the plate, or they may be 
fitted with threaded nuts through which the staybolt shall 
extend. The outside ends of solid staybolts 8 in. (200 mm) 
or less in length, if of uniform diameter throughout their 
length, shall be drilled with telltale holes at least 3 / i6 in. 
(5 mm) in diameter to a depth extending at least \ in. 
(13 mm) beyond the inside of the plate. If such staybolts 
are reduced in section below their diameter at the root of 
the thread, the telltale holes shall extend at least \ in. 
(13 mm) beyond the point where the reduction in section 
commences. Hollow staybolts may be used in place of 
solid staybolts with drilled ends. Solid staybolts over 8 
in. (200 mm) long need not be drilled. Staybolts used in 
waterlegs of watertube boilers shall be hollow or drilled 
at both ends, in accordance with the requirements above 
stated, irrespective of their length. All threaded staybolts 
not normal to the stayed surface shall have not less than 
three engaging threads of which at least one shall be a full 
thread; but if the thickness of the material in the boiler is 
not sufficient to give one full engaging thread, the plates 
shall be sufficiently reinforced on the inside by a steel 
plate welded thereto. Telltale holes are not required in 
staybolts attached by welding. 

HG-341.2 Staybolts Upset for Threading. The ends 
of steel stays upset for threading shall be fully annealed 
after upsetting. 

HG-341.3 Staybolts Fitted With Nuts. The ends of 
staybolts fitted with nuts shall not be exposed to direct 
radiant heat from fire. 

HG-341.4 Welded-in Staybolts. Requirements for 
welded-in staybolts are given in HW-710. 



HG-342 DIMENSIONS OF STAYS 

HG-342.1 Required Area of Stays. The required area 
of a stay at its minimum cross section (usually at the root 



of the thread) and exclusive of any allowance for corrosion 
shall be obtained by dividing the load on the stay computed 
in accordance with HG-342.2, HG-342.3, and HG-342.4 
by the allowable stress value for the material. 

HG-342.2 Load Carried by Stays. The area supported 
by a stay shall be computed on the basis of the full pitch 
dimensions with a deduction for the area occupied by the 
stay. The load carried by a stay is the product of the area 
supported by the stay and the design pressure. 

HG-342.3 Stays Longer Than 120 Diameters. Stays 
exceeding 120 diameters in length shall be supported at 
intervals not exceeding 120 diameters or the cross-sectional 
area of the stay shall be increased by not less than 15% 
of the required area of the stays calculated in HG-342.1. 

HG-342.4 Stays Fabricated by Welding. Stays made 
of parts jointed by welding shall be computed for strength 
using a joint efficiency of 60% for the weld. Welded stays 
shall be used only where it is impractical to use stays of 
one-piece construction. 

HG-342.5 Minimum Cross-Sectional Area. No fer- 
rous screwed stay, or ferrous stay welded in by the fusion 
process of welding shall have a cross-sectional area less 
than 0.44 in. 2 (284 mm 2 ). 

HG-342.6 Minimum Diameter of Nonferrous Stays 

(a) For nonferrous staybolted construction using 
unthreaded copper staybolts and copper plates, the mini- 
mum diameter of the staybolts shall be as follows: 



Copper Plate Thickness, in. (mm) 

Not exceeding \ (3) 

Over % (3), but not over \ t (5) 

Over \ 6 (5) 



Min. Staybolt 
Diameter, in. (mm) 

fc (13) 
% (16) 
X (19) 



(b) For nonferrous staybolted construction using 
unthreaded copper-nickel staybolts and copper-nickel 
plates, the minimum diameter of staybolts shall be as 
follows: 



Copper-Nickel Plate Thickness, 
in. (mm) 

Not exceeding \ (3) 

Over % (3), but not over \ (5) 

Over \ (5) 



Min. Staybolt 
Diameter, in. (mm) 

% (10) 

^16 (11) 

^ (13) 



HG-343 DIMENSIONS OF DIAGONAL STAYS 

HG-343.1 Required Area of Diagonal Stays. To deter- 
mine the required area of a diagonal stay, multiply the area 
of the direct stay, required to support the surface, by the 
slant or diagonal length of the stay; divide this product by 
the length of a line (drawn perpendicular to the surface 



24 



2007 SECTION IV 



TABLE HG-340 
ALLOWABLE PITCH 1 OF STAYS, in. (mm) (Limited by HG-340.3) 



Design Pressure, 








Plate Thickness, in. (mm) 








psi (kPa) 


V 4 (6.4) 


% 2 (7.1) 


5 /ie (7.9) 


% (8.7) 


% (9.5) 


13 / 32 (10.3) 


7 /l 6 (11.1) 


% (11.9) 


30 (207) 
40 (276) 
50 (345) 
60 (414) 


7 7 / 8 (200) 
6 13 / lfe (173) 
6V 16 (154) 
5 9 / 16 (141) 


8 13 /i 6 (224) 
7 5 / 8 (194) 
6 7 / 8 (175) 
6V 4 (159) 


9 13 / 16 (249) 
8V 2 (216) 
7 5 / 8 (194) 
6 15 / 16 (176) 


10 13 / 16 (275) 
9 3 / 8 (238) 
8 3 / 8 (213) 
7 5 / 8 (194) 


ll 13 /i 6 (300) 

10 3 / 16 (259) 

9% (232) 

8 5 / 16 (211) 


12 3 / 4 (324) 
llV 16 (281) 

9 7 / 8 (251) 

9 (229) 


13 3 / 4 (349) 
11 15 / 16 (303) 
10 5 / 8 (270) 
9 3 / 4 (248) 


15 (381) 
13 (330) 
ll 5 / 8 (295) 
10 5 / 8 (270) 


70 (483) 
75 (517) 
80 (552) 
90 (621) 


5% (130) 
4 15 / 16 (125) 
4 13 / 16 (122) 
4 9 / 16 (116) 


5 13 /i 6 (148) 
5 9 / 16 (141) 
5 3 / 8 (137) 
5% (130) 


6 7 / 16 (164) 
6V 4 (159) 
6 (152) 
5 n /i 6 (144) 


7V lfe (179) 
6 13 / 16 (173) 
6 5 / 8 (168) 
6V 4 (159) 


7 n / 16 (195) 
7 7 / 16 (189) 
7 3 / 16 (183) 
6% (173) 


8 3 / 8 (213) 
8 X / 16 (205) 
7 13 / 16 (198) 
7 3 / 8 (187) 


9 (229) 
8 n / 16 (221) 
8 7 /i 6 (214) 
7 15 / 16 (202) 


9 13 / i6 (249) 
9V 2 (241) 
9 3 / 16 (233) 
8 n / 16 (221) 


100 (690) 
110 (758) 
120 (827) 
125 (862) 


4 5 / 16 (110) 


4 13 / 16 (122) 
4 5 / 8 (117) 
4 7 / 16 (113) 
4 5 / 16 (110) 


5 3 / 8 (137) 
5V 8 (130) 
4 7 / 8 (124) 
4 13 / 16 (122) 


5 15 / 16 (151) 
5 5 / 8 (143) 
5 3 / 8 (137) 
5 5 / 16 (135) 


6 7 / 16 (164) 
b\ (156) 
5 7 / 8 (149) 
5 3 / 4 (146) 


7 (178) 
6% (170) 
6 3 / 8 (162) 
b\ (159) 


7 : / 2 (191) 
7 3 / 16 (183) 
6 7 / 8 (175) 
6 3 / 4 (171) 


8 3 /i 6 (208) 
7 13 / 16 (198) 
7V 2 (191) 
7 3 / 8 (187) 


130 (896) 
140 (965) 
150 (1034) 
160 (1103) 








5 3 / 16 (132) 
5 (127) 
4 13 / 16 (122) 
4 U / 16 (119) 


5 5 / 8 (143) 
5 7 / 16 (138) 
5V 4 (133) 
5% (130) 


6V 8 (156) 
5 7 / 8 (149) 
5 n / 16 (144) 
5V 2 (140) 


6 5 / 8 (168) 
6 3 / 8 (162) 
6V 8 (156) 
5 15 / 16 (151) 


7 3 / 16 (183) 
6 15 / 16 (176) 
6 n / 16 (170) 
6V 2 (165) 


Design Pressure, 








Plate Thickness, in. (mm) 








psi (kPa) 


V 2 (12.7) 


% (13.5) 


9 /l 6 (14.3) 


19 / 32 (15.1) 


% (15.9) 


21 / 32 (16.7) 


% (17.5) 


% (19.1) 


30 (207) 
40 (276) 
50 (345) 
60 (414) 


16 (406) 
13 7 / 8 (352) 
12 3 / 8 (314) 
ll 5 /i 6 (287) 


17 (432) 
14 3 / 4 (375) 
13 3 / 16 (335) 
11 15 / 16 (303) 


18 (457) 
15 n / 16 (398) 
13 15 / 16 (354) 
12 3 / 4 (324) 


19 (483) 
16 7 / 16 (418) 
14 3 / 4 (375) 
13 7 / 16 (341) 


20 (508) 
17 7 / 16 (440) 
15V 2 (394) 
14% (359) 


21 (533) 
18 3 / 16 (462) 
I6V4 (413) 
14 7 / 8 (378) 


22 (559) 
19V 16 (484) 
17V 16 (433) 
15 9 / 16 (395) 


24 (610) 
20 13 /i 6 (529) 
18 5 / 8 (473) 
17 (432) 


70 (483) 
75 (517) 
80 (552) 
90 (621) 


10V 2 (267) 
lOVg (257) 
9 13 / 16 (249) 
9V 4 (235) 


llV 8 (283) 
10 3 / 4 (273) 
10 7 / 16 (265) 
9 13 / 16 (249) 


11 13 / 16 (300) 
ll 3 / 8 (289) 
11 (279) 
10 3 / 8 (264) 


12 7 / 16 (316) 
12 (305) 
ll 5 / 8 (295) 
11 (279) 


13V 8 (333) 
12 5 / 8 (321) 
I2V4 (311) 
11 9 / 16 (294) 


13 3 / 4 (349) 
13 5 / 16 (338) 
12 7 / 8 (327) 
12V 8 (308) 


14 3 / 8 (365) 
13 15 / I6 (354) 
13V 2 (343) 
12 n / 16 (322) 


15 n /i 6 (398) 
15 3 / 16 (386) 
14 n / 16 (373) 
13 7 / 8 (352) 


100 (690) 
110 (758) 
120 (827) 
125 (862) 


8 3 / 4 (222) 
8 3 / 8 (213) 
8 (203) 
7 13 / 16 (198) 


9 5 / 16 (237) 
8 7 / 8 (225) 
8V 2 (216) 
8 5 / 16 (211) 


9 7 / 8 (251) 
9 3 / 8 (238) 
9 (229) 
8 7 / 8 (225) 


10 3 / 8 (264) 
9 15 / 16 (252) 
9V 2 (241) 
9 5 / 16 (237) 


10 15 / 16 (278) 
10 7 / lfe (265) 
10 (254) 
9 13 /i 6 (249) 


ll x /2 (292) 
11 (279) 
10V 2 (267) 
10 5 / 16 (262) 


12V16 (306) 
IIV2 (292) 
11 (279) 
10 3 / 4 (273) 


13V 8 (333) 
12 9 / 16 (319) 
12 (305) 
ll 3 / 4 (198) 


130 (896) 
140 (965) 
150 (1034) 
160 (1103) 


7 n / 16 (195) 
7 3 / 8 (187) 
l\ (181) 
6 15 / 16 (176) 


8 3 /i 6 (208) 
7 7 / 8 (200) 
7 5 / 8 (194) 
7 3 / 8 (187) 


8 5 / 8 (219) 
8 5 / 16 (211) 
8V 16 (205) 
7 13 / 16 (198) 


9% (232) 
8 13 / 16 (224) 
8 l / z (216) 
8V 4 (210) 


9 5 / 8 (244) 
9V4 (235) 
8 15 / 16 (227) 
8 n / 16 (221) 


10V 8 (257) 
9 3 / 4 (248) 
9 3 / 8 (238) 
9V I6 (230) 


10 9 / 16 (268) 
10 3 / 16 (259) 
9 13 /i 6 (249) 
9V2 (241) 


llV 2 (292) 
llVs (283) 
10 3 / 4 (273) 
10 7 / 16 (265) 


NOTE: 



















(1) The pitches in Table HG-340 are calculated from the formula p — Jt 2 x SC/P. In calculating these pitches, C = 2.7 for plate thicknesses 
not over 7 / 16 in. and C = 2.8 for plate thicknesses exceeding 7 / 16 in.; S = 11,000 psi. 



25 



2007 SECTION IV 



FIG. HG-343 DETAILS OF INSTALLATION OF DIAGONAL STAYS 






(a) 



(b) 



(c) 



GENERAL NOTES: 

(a) Determine area of diagonal stays per HG-343. 1. 

(b) Determine weld details and weld size for stay-to-tube-sheet and stay-to-shell per HW-710. 

(c) Determine diagonal stay pitch per HG-340.1. 

(d) Maximum r = 8t; minimum r = 3t; t = nominal thickness of tubesheet. 



supported) to the center of the palm of the diagonal stay, 
as follows: 

A ~ I 

where 

A = sectional area of diagonal stay, in. 2 (mm 2 ) 

a — sectional area of direct stay, in. 2 (mm 2 ) 

L = length of diagonal stay as indicated in 

Fig. HG-343, in. (mm) 
/ = length of line, drawn perpendicular to boiler head 
or surface supported, to center of palm of diagonal 
stay, as indicated in Fig. HG-343, in. (mm) 

Example: 

Given diameter of direct stay = 1 in., a = 0.7854 in. , 
L = 60 in., / = 48 in.; substituting and solving: 



A = 



0.78 54 x 60 
48 



= 0.98 sectional area, in. 



Diameter = 1.11 in. (Use \\ in.) 

HG-343.2 Diagonal Stays for Segments of Tube- 
sheets. For staying segments of tubesheets such as in hori- 
zontal firetube boilers, where L is not more than 1.15 times 
/ for any stay, the stays may be calculated as direct stays 
using 90% of the allowable stress values calculated in 
HG-342.1. 



HG-345 STAYING OF HEADS 
HG-345.1 General 

(a) Those portions of heads that require staying shall 
be stayed as flat plates under the provisions of these rules. 

(b) For unflanged heads in boilers designed for not over 
30 psi (200 kPa) pressure, with the heads attached with 



single fillet welds in accordance with HW-701 .3(a), staying 
is not required if the greatest distance measured along a 
radial line from the inner surface of the shell to a fully 
supported line does not exceed 1.25/?. For unflanged heads 
in boilers designed for over 30 psi (200 kPa) with heads 
attached in accordance with HW-701. 3(b), or for flanged 
heads of any pressure, staying is not required if the greatest 
distance measured as above does not exceed 1.5/?. The 
value of p shall be obtained by applying the equation of 
HG-340 with a C value of 2.7 or 2.8 depending on the 
plate thickness. 

(c) For purposes of applying the above paragraph, a 
fully supported line is a flanged or welded corner joint or 
is a line tangent to a row of tubes not over one pitch apart 
between edges and extending to within one pitch of the 
shell or the diametrically opposite side of the shell. 

(d) For unflanged heads, the maximum distance 
between the inner surface of the shell and the centers of 
stays shall not be more than the allowable pitch as deter- 
mined by HG-340, using the value of C given for the 
thickness of plate and the type of stay used. 

(e ) For a flanged head welded to the shell, the maximum 
distance between the inner surface of the supporting flange 
and lines parallel to the surface of the shell passing through 
the centers of the stays shall be p as determined by the 
formula in HG-340, plus the inside radius of the supporting 
flange, using the value of C given for the thickness of plate 
and the type of stay used. 

(f) The maximum distance between the edges of the 
tube holes and the center of the first row of stays shall be 
p as determined by the formula in HG-340, using the 
value of C given for the thickness Of plate and the type of 
stay used. 

(g) When a portion of the head in a horizontal firetube 
boiler is provided with a manhole opening, the flange of 



26 



2007 SECTION IV 



which is formed from the solid plate and turned inward to 
a depth of not less than three times the required thickness of 
the head, measured from the outside or, when an unflanged 
manhole ring meeting the requirements of HG-321 is pro- 
vided in a flat stayed head of a firetube boiler, the area to 
be stayed may be reduced by 100 in. 2 (645 cm 2 ) provided 
both the following requirements are met [see Figs. HG- 
345.1(a) and HG-345.1(b)]. 

(1) The distance between the manhole opening and 
the inner surface of the supporting flange does not exceed 
one-half the maximum allowable pitch for an unflanged 
manhole or one-half the maximum allowable pitch plus 
the inside radius of the supporting flange for a flanged-in 
manhole in a flanged head. 

(2) The distance between the centers of the first row 
of stays, or the edges of the tube holes, and the manhole 
opening does not exceed one-half the maximum allowable 
pitch as determined by HG-340. 



HG-346 TUBESHEETS WITH FIRETUBES 
USED AS STAYS 

HG-346. 1 Required Thickness, Maximum Pitch, and 
Design Pressure. The required thickness, maximum pitch, 
and design pressure for tubesheets with firetubes used as 
stays shall be calculated using the following formulas: 



(1) 



t = 


/(*-*) 


P 


/(f).(f) 

CSt 2 



p -I 



rD 2 



(2) 



(3) 



where 



C = 2.7 for tubesheets not over 7 / i6 in. (11 mm) thick 
= 2.8 for tubesheets over ^ 6 in. (11 mm) thick 

D = outside diameter of the tube 

P = design pressure 

p = maximum pitch measured between the centers of 
tubes in different rows, which lines may be hori- 
zontal, vertical, or inclined 

S = maximum allowable stress value given in 

Tables HF-300.1 and HF-300.2 
t = required thickness of plate 



HG-346.2 Maximum Pitch of Firetubes Used as 
Stays. The pitch of firetubes used as stays shall not exceed 
15 times the diameter of the tube. 

HG-346.3 Calculating Firetubes Used as Stays. No 

calculation need be made to determine the availability of 
the required cross-sectional area or the maximum allowable 
pitch for tubes within or on the perimeter of a nest of tubes, 
which are spaced at less than twice their average diameter. 

HG-346.4 Dimensions and Welding of Firetubes 
Used as Stays 

(a) The dimensions of firetubes used as stays shall meet 
the requirements of HG-312.2 and HG-342. 

(b) Firetubes used as stays may be attached by any 
method permitted in HG-360.2. 

(c) Firetubes welded to the tubesheet and used as stays 
shall meet the requirements of HW-713. 



HG-350 LIGAMENTS 

HG-350.1 General. The rules in this paragraph apply 
to groups of openings that form a definite pattern in cylin- 
drical pressure parts and to openings spaced not more than 
two diameters center to center. 

(a) The symbols defined below are used in the formulas 
of this paragraph: 

d = diameter of openings 
E = efficiency of ligament 
n = number of openings in length p\ 
p = longitudinal pitch of adjacent openings 
p' = diagonal pitch of adjacent openings 
p" = transverse pitch of adjacent openings 
P\ = pitch between corresponding openings in a series 
of symmetrical groups of openings 

(b) The efficiency of ligaments between openings is 
defined as the ratio of the average strength of the material 
between adjacent openings to the average strength of the 
plate away from the openings. Where a series of openings 
has more than one efficiency, the lowest value shall govern. 

(c) The pitch shall be measured on the flat plate before 
rolling. 

HG-350.2 Openings Parallel to Shell Axis. The liga- 
ment efficiency shall be determined as follows. 

(a) For equal pitch of openings in every row (see 
Fig. HG-350.1), the efficiency is given by the formula: 



p-d 



(1) 



(b) For unequal pitch in symmetrical groups of openings 
(as in Figs. HG-350.2 and HG-350.3), the efficiency is 
given by the formula: 



E = 



Px - nd 
P\ 



(2) 



27 



FIG. HG-345.1(a) SKETCH SHOWING APPLICATION OF HG-345.1 TO THE STAYING OF BOILERS 



HG-345.1 (c) 




GENERAL NOTES: 

(a) Required cross-sectional area to carry total load on segment based upon allowable stresses from Table HF-300.1 and 
computed by HG-342.1. 

(b) Provide the number of stays required to not exceed the maximum calculated pitch. 

(c) Diagonal stay stresses must not exceed limits computed from HG-343.1. 



HG-345.1 (f) 



11 Ai6 in. (17 mm) 
min. 
bearing 
surface 
HG-330.3 (c) 



FIG. HG-345.1(b) SKETCH SHOWING APPLICATION OF HG-345.1 TO THE STAYING OF BOILERS 



HG-345.1 (d) 



HG-345.1 (f)(1) 



11 /i6 in. (17 mm) 
min. 
bearing 
surface 
HG-330.3 (c) 




GENERAL NOTES: 

(a) Required cross-sectional area to carry total load on segment based upon allowable stresses from Table HF-300.1 and 
computed by HG-342.1. 

(b) Provide the number of stays required to not exceed the maximum calculated pitch. 

(c) Diagonal stay stresses must not exceed limits computed from HG-343.1. 



2007 SECTION IV 



FIG. HG-350.1 EXAMPLE OF TUBE SPACING WITH 
PITCH OF HOLES EQUAL IN EVERY ROW 



^ <? <? <? <? <? <? 
^ ^ ^ <^ ^ ^ <? 



& & 



& & & & 



& 



>s? 



•S? •&' -S? •$' 



■Sr 



(HHHHHHH) 



■sV «N* -.V ^ ^\* ^\* *N* 
<o <o <o <o <o <0 <0 



(HHHKKHH) 



Longitudinal Line 



(c) For openings that do not fall into symmetrical 
groups, the efficiency shall be the value calculated as fol- 
lows for the group of openings that gives the lowest effi- 
ciency: 

(1 ) the efficiency given by Formula (2) above using 
Px equal to the inside diameter of the shell or 60 in. 
(1 500 mm), whichever is less 

(2) 1.25 times the efficiency given by Formula (2) 
above using pi equal to the inside radius of the shell or 
30 in. (750 mm), whichever is less 

HG-350.3 Openings Transverse to Shell Axis. The 

ligament efficiency of openings spaced at right angles to 
the axis of the shell is equal to two times the efficiency 
of similarly spaced holes parallel to the shell axis as calcu- 
lated in accordance with the rules in HG-350.2. 



FIG. HG-350.2 EXAMPLE OF TUBE SPACING WITH 
PITCH OF HOLES UNEQUAL IN EVERY SECOND ROW 






& s 



& s 



& s 



i 



& 



HG-350.4 Holes Along a Diagonal. The ligament effi- 
ciency shall be determined as follows. 

(a) The efficiency of openings that are equally spaced 
along diagonal lines (see Fig. HG-350.4) is given by the 
formula: 



•^ .£•• 



^' £- 



.? 






A* 



e-e-ee-ee-ee 



<o 



12 in. 
(305 mm) 

Longitudinal Line 



E = 



p'-d 
P'F 



(3) 



where F is a factor from Fig. HG-321 for the angle that 
the diagonal makes with a plane through the longitudinal 
axis of the boiler. 

(b) The ligament efficiency of openings that are 
unequally spaced along diagonal lines shall be determined 
as in HG-350.1(c) except that Formula (3) shall be used 
in place of Formula (2). 



FIG. HG-350.3 EXAMPLE OF TUBE SPACING WITH PITCH OF HOLES VARYING IN 
EVERY SECOND AND THIRD ROW 



& 






A 



& A 



■£? 



<o <o 



"C "C V" 

-s\* *\* o^> 
<o <o <b 



ee-eee-ee-eee 
e-e-eee-ee-eee 






& Ǥ> 



.C 






29V 4 in. 
(743 mm) 



Longitudinal Line 



30 



2007 SECTION IV 



FIG. 



HG-350.4 EXAMPLE OF TUBE SPACING WITH 
TUBE HOLES ON DIAGONAL LINES 



TABLE HG-360 
PERMITTED O-RING MATERIALS 




5 3 /4 in. 
(146 mm) 

Longitudinal Line 



HG-360 REQUIREMENTS FOR TUBE HOLES 
AND TUBE ATTACHMENTS 
HG-360.1 Tube Holes and Ends 

(a) Tube holes shall be drilled full size from the solid 
plate, or they may be punched \ m - (13 mm) smaller in 
diameter than full size when the plate thickness exceeds 
% in. (10 mm) and V% in. (3 mm) smaller in diameter than 
full size when the plate thickness is \ in. (10 mm) or less, 
and then drilled, reamed, or finished full size with rotating 
cutters. Tube holes may be counterbored where the metal 
is thicker than that required to get a proper bearing by 
expanding, so as to form narrow seats into which the tube 
ends can properly expand, provided there is space available 
to permit a proper amount of flare of the tube end. 

(b) The sharp edges of tube holes shall be taken off on 
both sides of the plate with a file or other tool. 

HG-360.2 Attachment of Firetubes 

(a) Ends of firetubes may be expanded, expanded and 
flared, expanded and beaded, expanded and welded, or 
welded. Firetubes that require consideration as stays in 
HG-346 shall not be attached by expanding alone. 

(b) Firetubes attached by expanding and welding or 
welding shall comply with HW-713. 

(c) Firetubes attached by expanding and flaring or 
expanding shall comply with the following: 

(1) If the firetube ends are in contact with primary 
furnace gases, the tubes shall extend beyond the tube-sheet 
a distance not less than the tube thickness or V$ in. (3 mm), 
whichever is greater, but not more than \ in. (6 mm) or 
the tube thickness, whichever is greater. 

(2) If the firetube ends are not in contact with primary 
furnace gases, the tubes shall extend beyond the tubesheet 
a distance not less than the tube thickness or % in. (3 mm), 
whichever is greater, but not more than % in. (10 mm) or 
the tube thickness, whichever is greater. 

(d) Where firetubes are attached by welding, the tube 
holes may be drilled, flame cut, or punched. The tube holes 



Material 



Temperature Limit, 
°F (°C) 



Hydrogenated IMitrile Rubber (HNBR) 300 (150) 

Ethylene Propylene Diene Rubber (EPDM) 300 (150) 

TFE/Propropylene Rubber (FEPM) 450 (230) 

Perfluorinated Elastomer (FFKM) 480 (250) 



may be punched full size provided the thickness of the 
tubesheet does not exceed /^ 6 in. (8 mm). The diameter of 
the tube hole in any case shall not be more than l / 3 2 m - 
(0.8 mm) greater than the outside diameter of the tube. 

HG-360.3 Attachment of Watertubes 

(a) Watertubes may be attached by expanding, 
expanding and flaring, expanding and beading, expanding 
and welding, or welding. Watertubes attached by 
expanding and welding or welding shall comply with 
HW-713. 

(b) Where attached by other than expanding and bead- 
ing, the tubes shall extend beyond the tubesheet a distance 
not less than \ in. (6 mm) nor more than \ in. (13 mm). 

(c) Watertubes not exceeding 2 in. (50 mm) O.D. may 
be attached mechanically with welded tapered ferrules. 
When such method of attachment is used, the tapered fer- 
rule shall completely penetrate the head or drum and be 
mechanically clamped to the header or drum with bolting 
of no less than \ in. (10 mm) diameter, and the tubing 
shall not be used to support the pressure vessel. 

(d) Where watertubes are attached by welding, the tube 
holes may be drilled, flame cut, or punched. The tube holes 
may be punched full size provided the thickness of the 
tubesheet does not exceed 5 / i6 in. (8 mm). The diameter of 
the tube hole in any case shall not be more than V 32 i n - 
(0.8 mm) greater than the outside diameter of the tube. 

(e) Watertubes in hot water boilers may be installed into 
headers with the use of O-ring seals in lieu of expanding, 
welding, or brazing, provided the following conditions 
are met. 

(1) The tube hole diameter shall be not more than %2 
in. (0.8 mm) larger than the outside diameter of the tube. 

(2) The tube hole shall be recessed to accommodate 
the O-ring. 

(3) The dimensions of both the O-ring and its 
retaining groove shall be in accordance with the O-ring 
manufacturer's recommendations. 

(4) The O-ring material shall be suitable for the 
design conditions. Material selections shall be limited to 
those shown in Table HG-360. 

(5) The O-ring shall be located or shielded in a man- 
ner determined by the boiler Manufacturer to preclude the 
O-ring from being exposed to temperatures higher than the 



31 



2007 SECTION IV 



maximum temperature listed in Table HG-360. 

(6) The headers shall be held together by stays ade- 
quately designed to carry the end loading and prevent the 
headers from spreading apart. The maximum allowable 
stress value of the stays shall not exceed that permitted in 
Table HF-300.1. 

(7) Means shall be provided to prevent the tubes from 
losing contact with the O-ring seal due to tube movement 
without loosening the stays. 

(8) If the tube length exceeds 6 ft (1.8 m), the tubes 
shall be supported at their midlength. 

HG-370 EXTERNAL PIPING CONNECTIONS 

HG-370.1 Threaded Connections. Pipe connections, 
if threaded, shall be tapped into material having a minimum 
thickness as specified in Table HG-370, except that when 
a curved surface is to be tapped the minimum thickness 
shall be sufficient to permit at least four full threads to be 
engaged. 

HG-370.2 Flanged Connections 

(a) It is recommended that dimensional requirements 
of bolted flange connections to external piping conform to 



TABLE HG-370 

MINIMUM THICKNESS OF MATERIAL FOR 

THREADED CONNECTIONS TO BOILERS 



Size of Pipe Connection, 


DN 


Minimum Thickness of Material 


in. (mm) 




Required, in. (mm) 


Under % (20) 




V 4 (6) 


% to 1 (20 to 25), incl. 




5 /i6 (8) 


lV 4 to 2V 2 (32 to 65), incl. 




7 / 16 (11) 


3 to 3V 2 (80 to under 100), 


, incl. 


% (16) 


4 to 5 (100 to 125), incl. 




7 / 8 (22) 


6 to 8 (150 to 200), incl. 




1 (25) 


9 to 12 (Over 200 to 300), 


incl. 


lV 4 (32) 



ANSI B 16.5, Steel Pipe Flanges and Flanged Fittings. Such 
flanges may be used for pressure-temperature ratings in 
accordance with the Standard. 

(b) Steel flanges that do not conform to ANSI B16.5 
shall be designed in accordance with the rules in 
Appendix II of Section VIII, Division 1, for the design 
pressure and temperature conditions. The outside diameter 
and bolting shall conform to a standard approved by ANSI. 



32 



2007 SECTION IV 



ARTICLE 4 
PRESSURE RELIEVING DEVICES 



HG-400 PRESSURE RELIEVING VALVE 
REQUIREMENTS 
HG-400.1 Safety Valve Requirements for Steam 
Boilers 

(a) Each steam boiler shall have one or more officially 
rated safety valves that are identified with the V or HV 
Symbol of the spring pop type adjusted and sealed to 
discharge at a pressure not to exceed 15 psi (100 kPa). 
07 (b) No safety valve for a steam boiler shall be smaller 
than NPS \ (DN 15) or larger than NPS 4 (DN 100). The 
inlet opening shall have an inside diameter equal to, or 
greater than, the seat diameter. 

(c) The minimum relieving capacity of valve or valves 
shall be governed by the capacity marking on the boiler 
called for in HG-530. 

(d) The minimum valve capacity in pounds per hour 
shall be the greater of that determined by dividing the 
maximum Btu output at the boiler nozzle obtained by the 
firing of any fuel for which the unit is installed by 1,000, 
or shall be determined on the basis of the pounds (kg) of 
steam generated per hour per square foot (m 2 ) of boiler 
heating surface as given in Table HG-400. 1 . For cast iron 
boilers constructed to the requirements of Part HC, the 
minimum valve capacity shall be determined by the maxi- 
mum output method. In many cases a greater relieving 
capacity of valves will have to be provided than the mini- 
mum specified by these rules. In every case, the require- 
ment of HG-400. 1(e) shall be met. 

(e) The safety valve capacity for each steam boiler shall 
be such that with the fuel burning equipment installed, and 
operated at maximum capacity, the pressure cannot rise 
more than 5 psi (35 kPa) above the maximum allowable 
working pressure. 

(f) When operating conditions are changed, or addi- 
tional boiler heating surface is installed, the valve capacity 
shall be increased, if necessary, to meet the new conditions 
and be in accordance with HG-400. 1(e). The additional 
valves required, on account of changed conditions, may 
be installed on the outlet piping provided there is no 
intervening valve. 

HG-400.2 Safety Relief Valve Requirements for Hot 
Water Boilers 

(a) Each hot water heating or supply boiler shall have at 
least one officially rated safety relief valve, of the automatic 



TABLE HG-400.1 

MINIMUM POUNDS OF STEAM PER HOUR (kg/hr) 

PER SQUARE FOOT (METER) OF HEATING SURFACE 





Firetube 


Watertube 


Boiler Heating Surface 


Boilers 


Boilers 


Hand fired 


5 (24) 


6 (29) 


Stoker fired 


7 (34) 


8 (39) 


Oil, gas, or pulverized 






fuel fired 


8 (39) 


10 (49) 


Waterwall heating surface: 






Hand fired 


8 (39) 


8 (39) 


Stoker fired 


10 (49) 


12 (59) 


Oil, gas, or pulverized 






fuel fired 


14 (68) 


16 (78) 



GENERAL NOTES: 

(a) When a boiler is fired only by a gas having a heat value not in 
excess of 200 Btu/ft 3 (7 400 kj/m 3 ), the minimum safety valves 
or safety relief valve relieving capacity may be based on the values 
given for hand fired boilers above. 

(b) The minimum safety valve or safety relief valve relieving capacity 
for electric boilers shall be 3 l / 2 Ib/hr/kW (1.6 kg/hr/kW) input. 

(c) For heating surface determination, see HG-403. 

(d) For extended heating surface, the minimum Ib/hr/sq ft may be 
determined by the Manufacturer [see HG-403(d)L 



reseating type, identified with the V or HV Symbol, and 
set to relieve at or below the maximum allowable working 
pressure of the boiler. 

(b) Hot water heating or supply boilers limited to a 
water temperature not in excess of 210°F (99°C) may have, 
in lieu of the valve(s) specified in (a) above, one or more 
officially rated temperature and pressure safety relief valves 
of the automatic reseating type identified with the HV 
symbol, and set to relieve at or below the maximum allow- 
able working pressure of the boiler. 

(c) When more than one safety relief valve is used on 
either hot water heating or hot water supply boilers, the 
additional valves shall be officially rated and may have a 
set pressure within a range not to exceed 6 psi (40 kPa) 
above the maximum allowable working pressure of the 
boiler up to and including 60 psi (400 kPa), and 5% for 
those having a maximum allowable working pressure 
exceeding 60 psi (400 kPa). 

(d) No safety relief valve shall be smaller than NPS % 
(DN 20) nor larger than NPS 4 (DN 100) except that boilers 



07 



33 



2007 SECTION IV 



having a heat input not greater than 15,000 Btu/hr (4.4 kW) 
may be equipped with a rated safety relief valve of NPS \ 
(DN 15). 

( e) The required steam relieving capacity, in pounds per 
hour (kg/h), of the pressure relieving device or devices on 
a boiler shall be the greater of that determined by dividing 
the maximum output in Btu at the boiler nozzle obtained 
by the firing of any fuel for which the unit is installed by 
1 ,000, or shall be determined on the basis of pounds (kg) 
of steam generated per hour per square foot (m 2 ) of boiler 
heating surface as given in Table HG-400.1. For cast iron 
boilers constructed to the requirements of Part HC, the 
minimum valve capacity shall be determined by the maxi- 
mum output method. In many cases a greater relieving 
capacity of valves will have to be provided than the mini- 
mum specified by these rules. In every case, the require- 
ments of HG-400.2(g) shall be met. 

(f) When operating conditions are changed, or addi- 
tional boiler heating surface is installed, the valve capacity 
shall be increased, if necessary, to meet the new conditions 
and shall be in accordance with HG-400.2(g). The addi- 
tional valves required, on account of changed conditions, 
may be installed on the outlet piping provided there is no 
intervening valve. 

(g) Safety relief valve capacity for each boiler with a 
single safety relief valve shall be such that, with the fuel 
burning equipment installed and operated at maximum 
capacity, the pressure cannot rise more than 10% above 
the maximum allowable working pressure. When more 
than one safety relief valve is used, the overpressure shall 
be limited to 10% above the set pressure of the highest set 
valve allowed by HG-400.2(a). 

HG-400.3 Safety and Safety Relief Valves for Tanks 
and Heat Exchangers 

(a) Steam to Hot Water Supply. When a hot water supply 
is heated indirectly by steam in a coil or pipe within the 
service limitations set forth in HG-101, the pressure of the 
steam used shall not exceed the safe working pressure of 
the hot water tank, and a safety relief valve at least NPS 1 
(DN 25), set to relieve at or below the maximum allowable 
working pressure of the tank, shall be applied on the tank. 

(b) High Temperature Water to Water Heat Exchanger. l 
When high temperature water is circulated through the 
coils or tubes of a heat exchanger to warm water for space 
heating or hot water supply, within the service limitations 
set forth in HG-101, the heat exchanger shall be equipped 
with one or more officially rated safety relief valves that 
are identified with the V or HV Symbol, set to relieve at 
or below the maximum allowable working pressure of the 
heat exchanger, and of sufficient rated capacity to prevent 
the heat exchanger pressure from rising more than 10% 



1 Suggested installation practices for the secondary side of heat 
exchangers. 



above the maximum allowable working pressure of the 
vessel. 

(c) High Temperature Water to Steam Heat Exchanger. l 
When high temperature water is circulated through the 
coils or tubes of a heat exchanger to generate low pressure 
steam, within the service limitations set forth in HG-101, 
the heat exchanger shall be equipped with one or more 
officially rated safety valves that are identified with the V 
or HV Symbol, set to relieve at a pressure not to exceed 
15 psi (100 kPa), and of sufficient rated capacity to prevent 
the heat exchanger pressure from rising more than 5 psi 
(35 kPa) above the maximum allowable working pressure 
of the vessel. For heat exchangers requiring steam pressures 
greater than 15 psi (100 kPa), refer to Section I or Section 
VIII, Division 1. 



HG-401 MINIMUM REQUIREMENTS FOR 
SAFETY AND SAFETY RELIEF 
VALVES 
HG-401.1 Mechanical Requirements 

(a) The inlet opening shall have an inside diameter 
approximately equal to, or greater than, the seat diameter. 
In no case shall the maximum opening through any part 
of the valve be less than V 4 in. (6 mm) in diameter or its 
equivalent area. 

(b) Safety relief valves officially rated as to capacity 
shall have pop action when tested by steam. 

(c) O-rings or other packing devices when used on the 
stems of safety relief valves shall be so arranged as not to 
affect their operation or capacity. 

(d) The design shall incorporate guiding arrangements 
necessary to insure consistent operation and tightness. 
Excessive lengths of guiding surfaces should be avoided. 
Bottom guided designs are not permitted on safety relief 
valves. 

(e) Safety valves shall have a controlled blowdown of 
2 psi to 4 psi (15 kPa to 30 kPa) and this blowdown need 
not be adjustable. 

(f) Safety valves shall be spring loaded. The spring shall 
be designed so that the full lift spring compression shall 
be no greater than 80% of the nominal solid deflection. 
The permanent set of the spring (defined as the difference 
between the free height and height measured 10 min after 
the spring has been compressed solid three additional times 
after presetting at room temperature) shall not exceed 0.5% 
of the free height. 

(g) There shall be a lifting device and a mechanical 
connection between the lifting device and the disk capable 
of lifting the disk from the seat a distance of at least fa in. 
(1.5 mm) with no pressure on the boiler. 

(h) A body drain below seat level shall be provided by 
the Manufacturer for all safety valves and safety relief 
valves, except that the body drain may be omitted when 



34 



2007 SECTION IV 



the valve seat is above the bottom of the inside diameter 
of the discharge piping. For valves exceeding NPS 2 l / 2 
(DN 65) the drain hole or holes shall be tapped not less 
than NPS % (DN 10). For valves NPS 2 x / 2 (DN 65) or 
smaller, the drain hole shall not be less than \ in. (6 mm) 
in diameter. Body drain connections shall not be plugged 
during or after field installation. In safety relief valves of 
the diaphragm type, the space above the diaphragm shall 
be vented to prevent a buildup of pressure above the dia- 
phragm. Safety relief valves of the diaphragm type shall 
be so designed that failure or deterioration of the diaphragm 
material will not impair the ability of the valve to relieve 
at the rated capacity. 

(i) In the design of the body of the valve consideration 
shall be given to minimizing the effects of water deposits. 

(j) Valves shall be provided with wrenching surfaces to 
allow for normal installation without damaging 
operating parts. 

(k) The set pressure tolerances, plus or minus, of safety 
valves shall not exceed 2 psi (15 kPa), and for safety relief 
valves shall not exceed 3 psi (20 kPa) for pressures up to 
and including 60 psig (400 kPa) and 5% for pressures 
above 60 psig (400 kPa). 

(7) Safety valves shall be arranged so that they cannot 
be reset to relieve at a higher pressure than the maximum 
allowable working pressure of the boiler. 

HG-401.2 Material Selection 

(a) Cast iron seats and disks are not permitted. 

(b) Adjacent sliding surfaces such as guides and disks 
shall both be of corrosion resistant material. 

(c) Springs of corrosion resistant material or having a 
corrosion resistant coating are required. 

(d) Material for seats and disks should be such as to 
provide a reasonable degree of resistance to steam cutting. 

(e) Material for valve bodies and bonnets or their corres- 
ponding metallic pressure containing parts shall be listed 
in Section II, except that in cases where a manufacturer 
desires to make use of materials other than those listed in 
Section II, he shall establish and maintain specifications 
requiring equivalent control of chemical and physical prop- 
erties and quality. 

(f) Synthetic disk inserts of O-ring or other types if used 
shall be compatible with the maximum design temperature 
established for the valve. 

(g) No materials liable to fail due to deterioration or 
vulcanization when subjected to saturated steam tempera- 
ture corresponding to capacity test pressure shall be used. 

HG-401.3 Manufacture and Inspection 

(a) A Manufacturer shall demonstrate to the satisfaction 
of an ASME designee that his manufacturing, production, 
and testing facilities and quality control procedures will 
insure close agreement between the performance of random 



production samples and the performance of those valves 
submitted for capacity certification. 

(b) Manufacturing, inspection, and test operations 
including capacity are subject to inspections at any time 
by an ASME designee. 

(c) A Manufacturer may be granted permission to apply 
the HV Code Symbol to production pressure relief valves 
capacity certified in accordance with HG-402.3 provided 
the following tests are successfully completed. This per- 
mission shall expire on the fifth anniversary of the date it 
is initially granted. The permission may be extended for 
5 year periods if the following tests are successfully 
repeated within the 6 month period before expiration. 

(1) Two sample production pressure relief valves of 
a size and capacity within the capability of an ASME 
accepted laboratory shall be selected by an ASME des- 
ignee. 

(2) Operational and capacity tests shall be conducted 
in the presense of an ASME designee at an ASME accepted 
laboratory. The valve Manufacturer shall be notified of the 
time of the test and may have representatives present to 
witness the test. 

(3) Should any valve fail to relieve at or above its 
certified capacity or should it fail to meet performance 
requirements of this Section, the test shall be repeated at 
the rate of two replacement valves, selected in accordance 
with HG-401. 3(c)(1), for each valve that failed. 

(4) Failure of any of the replacement valves to meet 
the capacity or the performance requirements of this Sec- 
tion shall be cause for revocation within 60 days of the 
authorization to use the Code Symbol on that particular 
type of valve. During this period, the Manufacturer shall 
demonstrate the cause of such deficiency and the action 
taken to guard against future occurrence, and the require- 
ments of HG-401. 3(c) above shall apply. 

(d) Safety valves shall be sealed in a manner to prevent 
the valve from being taken apart without breaking the seal. 
Safety relief valves shall be set and sealed so that they 
cannot be reset without breaking the seal. 

HG-401.4 Manufacturer's Testing 

(a) Every safety valve shall be tested to demonstrate its 
popping point, blowdown, and tightness. Every safety relief 
valve shall be tested to demonstrate its opening point and 
tightness. Safety valves shall be tested on steam or air 
and safety relief valves on water, steam, or air. When the 
blowdown is nonadjustable, the blowdown test may be 
performed on a sampling basis. 

(b) A Manufacturer shall have a well-established pro- 
gram for the application, calibration, and maintenance of 
test gages. 

(c) Testing time on safety valves shall be sufficient, 
depending on size and design, to insure that test results 
are repeatable and representative of field performance. 



35 



2007 SECTION IV 



FIG. HG-402 OFFICIAL SYMBOL FOR STAMP 

TO DENOTE THE AMERICAN SOCIETY OF 

MECHANICAL ENGINEERS' STANDARD 




(d) Test fixtures and test drums shall be of adequate 
size and capacity to assure representative pop action and 
accuracy of blowdown adjustment. 

(e) A tightness test shall be conducted at maximum 
expected operating pressure, but not at a pressure exceeding 
the reseating pressure of the valve. 

HG-401.5 Design Requirements. At the time of the 
submission of valves for capacity certification, or testing 
in accordance with this Section, the ASME Designee has 
the authority to review the design for conformity with 
the requirements of this Section, and to reject or require 
modification of designs that do not conform, prior to capac- 
ity testing. 



HG-402 DISCHARGE CAPACITIES OF 
SAFETY AND SAFETY RELIEF 
VALVES 

HG-402. 1 Valve Markings. Each safety or safety-relief 
valve shall be plainly marked with the required data by 
the Manufacturer in such a way that the markings will not 
be obliterated in service. The markings shall be stamped, 
etched, impressed, or cast on the valve or on a hameplate, 
which shall be securely fastened to the valve. 

(a) The markings shall include the following: 

(1) the name or an acceptable abbreviation of the 
Manufacturer 

(2) Manufacturer's design or type number 

(3) NPS size in. (DN) (the nominal pipe size 

of the valve inlet) 

(4) set pressure psi 

(5) capacity lb/hr (kg/hr), or capacity 

Btu/hr in accordance with HG-402.7(a) 



(6) year built or, alternatively, a coding may be 
marked on the valves such that the valve Manufacturer can 
identify the year the valve was assembled and tested, and 

(7) ASME Symbol as shown in Fig. HG-402 

(b) Nameplates of safety or safety-relief valves may be 
marked solely in metric units under the following condi- 
tions: 

(1) The pressure-relief device will be installed in a 
location where metric units are required or accepted by 
local authorities, if any. 



(2) Metric units shall be those required by the user 
when not mandated by enforcement authorities. 

(3) The Manufacturer's quality control system shall 
provide for the conversion from U.S. customary units to 
the metric units that will be marked on the nameplate. 

HG-402.2 Authorization to Use ASME Stamp. Each 
safety valve to which the Code Symbol (Fig. HG-402) is 
to be applied shall be produced by a Manufacturer and /or 
Assembler who is in possession of a valid Certificate of 
Authorization. (See HG-540.) 

For all valves to be stamped with the HV Symbol, a 
Certified Individual (CI) shall provide oversight to ensure 
that the use of the "HV" Code symbol on a safety valve 
or safety relief valve is in accordance with this Section 
and that the use of the "HV" Code symbol is documented 
on a Certificate of Conformance Form, HV-1. 

(a) Requirements for the Certified Individual (CI). The 
CI shall 

(1) be an employee of the Manufacturer. 

(2) be qualified and certified by the Manufacturer. 
Qualification shall include the following as a minimum: 

(a) knowledge of the requirements of this Section 
for the application of the "HV" Code Symbol 

(b) knowledge of the Manufacturer's quality 
program 

(c) training commensurate with the scope, com- 
plexity, or special nature of the activities to which oversight 
is to be provided 

(3) have a record, maintained and certified by the 
Manufacturer, containing objective evidence of the quali- 
fications of the CI and the training program provided 

(b) Duties of the Certified Individual (CI). The CI shall 

(1) verify that each item to which the Code Symbol 
is applied meets all applicable requirements of this Section 
and has a current capacity certification for the "HV" symbol 

(2) review documentation for each lot of items to be 
stamped, to verify, for the lot, that the requirements of this 
Section have been completed 

(3) sign the Certificate of Conformance Form (HV-1) 
prior to release of control of the item 

(c) Certificate of Conformance Form (HV-1) (see 
Appendix N) 

(1) The Certificate of Conformance shall be filled out 
by the Manufacturer and signed by the Certified Individual. 
Multiple duplicate pressure relief devices may be recorded 
on a single entry provided the devices are identical and 
produced in the same lot. 

(2) The Manufacturer's written quality control pro- 
gram shall include requirements for completion of Certifi- 
cates of Conformance forms and retention by the 
Manufacturer for a minimum of 5 years. 

HG-402.3 Determination of Capacity to Be Stamped 
on Valves. The Manufacturer of the valves that are to be 



36 



2007 SECTION IV 



stamped with the Code symbol shall submit valves for 
testing to a place where adequate equipment and personnel 
are available to conduct pressure and relieving-capacity 
tests which shall be made in the presence of and certified 
by an authorized observer. The place, personnel, and 
authorized observer shall be approved by the Boiler and 
Pressure Vessel Committee. The valves shall be tested in 
one of the following three methods. 

(a) Coefficient Method. Tests shall be made to determine 
the lift, popping, and blowdown pressures, and the capacity 
of at least three valves each of three representative sizes 
(a total of nine valves). Each valve of a given size shall 
be set at a different pressure. However, safety valves for 
steam boilers shall have all nine valves set at 15 psig 
(100 kPa). A coefficient shall be established for each test 
as follows: 



K r 



Actual steam flow 
Theoretical steam flow 



Coefficient of 
discharge 



The average of the coefficients K D of the nine tests required 
shall be multiplied by 0.90, and this product shall be taken 
as the coefficient K of that design. The stamped capacity 
for all sizes and pressures shall not exceed the value deter- 
mined from the following formulas: 

For 45 deg seat, 

(U.S. Customary Units) 

W = 51.5 TtDLP x 0.101 K 
(SI Units) 

W = 5.25 ttDLP x 0.101 K 
For flat seat, 
(U.S. Customary Units) 

W = 51.5 ttDLPK 
(SI Units) 

W = 5.25 ttDLP 
For nozzle, 

(U.S. Customary Units) 

W = 51.5APK 
(SI Units) 

W = 5.25 APR 

where 

A — nozzle-throat area 

D = seat diameter 

K = coefficient of discharge for the design 

L = lift 



P = (1.10 x set pressure + 14.7) psia or (1.10 x set 
pressure + 0.101) MPa, for hot water applica- 
tions or 
= (5.0 psi + 15 psi set + 14.7) psia or (0.035 MPa 
+ 0.100 MPa set + 0.101) MPa, for steam boilers 

W = weight of steam /hr 

NOTE: The maximum and minimum coefficient determined by the tests 
of a valve design shall not vary more than ±5% from the average. If 
one or more tests are outside the acceptable limits, one valve of the 
Manufacturer's choice shall be replaced with another valve of the same 
size and pressure setting or by a modification of the original valve. 
Following this test a new average coefficient shall be calculated, excluding 
the replaced valve test. If one or more tests are now outside the acceptable 
limits, as determined by the new average coefficient, a valve of the 
Manufacturer's choice must be replaced by two valves of the same size 
and pressure as the rejected valve. A new average coefficient, including 
the replacement valves, shall be calculated. If any valve, excluding the 
two replaced valves, now falls outside the acceptable limits, the tests 
shall be considered unsatisfactory. 

(b) Slope Method. If a Manufacturer wishes to apply 
the Code Symbol to a design of pressure relief valves, four 
valves of each combination of pipe and orifice size shall 
be tested. These four valves shall be set at pressures that 
cover the approximate range of pressures for which the 
valve will be used, or that cover the range available at 
the certified test facility that shall conduct the tests. The 
capacities shall be based on these four tests as follows: 

(1) The slope (W/P) of the actual measured capacity 
versus the flow pressure for each test point shall be calcu- 
lated and averaged: 



slope = W/P = 



measured capacity 
absolute flow pressure, psia 



All values derived from the testing must fall within ±5% 
of the average value: 

minimum slope = 0.95 X average slope 

maximum slope = 1.05 x average slope 

If the values derived from the testing do not fall between 
the minimum and maximum slope values, the Authorized 
Observer shall require that additional valves be tested at 
the rate of two for each valve beyond the maximum and 
minimum values with a limit of four additional valves. 

(2) The relieving capacity to be stamped on the valve 
shall not exceed 90% of the average slope times the abso- 
lute accumulation pressure: 

rated slope = 0.90 X average slope 

stamped capacity < rated slope x (1.10 X set pressure + 14.7) 
psia or (1 . 10 X set pressure +101) kPa for hot water applications 

(c) Three-Valve Method. If a Manufacturer wishes to 
apply the Code Symbol to steam safety valves or safety 
relief valves of one or more sizes of a design set at one 



37 



2007 SECTION IV 



pressure, he shall submit three valves of each size of each 
design set at one pressure for testing and the stamped 
capacity of each size shall not exceed 90% of the average 
capacity of the three valves tested. 

NOTE: The discharge capacity as determined by the test of each valve 
tested shall not vary by more than ±5% of the average capacity of the 
three valves tested. If one of the three valve tests falls outside of the 
limits, it may be replaced by two valves and a new average calculated 
based on all four valves, excluding the replaced valve. 

HG-402.4 Pressures at Which Capacity Tests Shall 
Be Conducted. Safety valves for steam boilers shall be 
tested for capacity at 5 psi (35 kPa) over the set pressure 
for which the valve is set to operate. Capacity certification 
tests of safety relief valves for hot water heating and hot 
water supply boilers shall be conducted at 110% of the 
pressure for which the valve is set to operate. 

HG-402.5 Opening Tests of Temperature and Pres- 
sure Safety Relief Valves. For the purpose of determining 
the set (opening) pressure, the test medium shall be room 
temperature water. The actual set pressure is defined as 
the pressure at the valve inlet when the flow rate through 
the valve is 40 cc/min. Capacity tests shall be conducted 
with steam (see HG-402.7) at a pressure 10% above the 
actual water set pressure. For production capacity check 
tests, the rated capacity shall be based on the actual water 
set pressure. 

HG-402.6 Capacity Tests of Temperature and Pres- 
sure Safety Relief Valves. For the purpose of determining 
the capacity of temperature and pressure safety relief 
valves, dummy elements of the same size and shape as the 
regularly applied thermal element shall be substituted and 
the relieving capacity shall be based on the pressure ele- 
ment only. Valves selected to meet the requirements of 
production testing, HG-401.3, shall have their temperature 
elements deactivated by the Manufacturer prior to or at 
the time of capacity testing. 

HG-402.7 Fluid Medium for Capacity Tests. The 

tests shall be made with dry saturated steam. For test pur- 
poses the limits of 98% minimum quality and 20°F (10°C) 
maximum superheat shall apply. Correction from within 
these limits may be made to the dry saturated condition. 
The relieving capacity shall be measured by condensing 
the steam or with a calibrated steam flowmeter. 

To determine the discharge capacity of safety relief 
valves in terms of Btu, the relieving capacity in pounds 
for steam per hour W is multiplied by 1,000. 



HG-402.8 Where and by Whom Capacity Tests Shall 
Be Conducted 

(a) Tests shall be conducted at a place where the testing 
facilities, methods, procedures, and person supervising the 
tests (Authorized Observer) meet the applicable require- 
ments of ASME PTC 25. The tests shall be made under 
the supervision of and certified by an Authorized Observer. 
The testing facilities, methods, procedures, and qualifica- 
tions of the Authorized Observer shall be subject to the 
acceptance of ASME on recommendation of an ASME 
Designee. Acceptance of the testing facility is subject to 
review within each 5 year period. 

(b) Capacity test data reports for each valve model, type, 
and size, signed by the Manufacturer and the Authorized 
Observer witnessing the tests, shall be submitted to the 
ASME Designee for review and acceptance. 2 

NOTE: When changes are made in the design, capacity certification 
tests shall be repeated. 

HG-402.9 Test Record Data Sheet. A data sheet for 
each valve shall be filled out and signed by the authorized 
observer witnessing the test. Such data sheet will be the 
manufacturer's authority to build and stamp valves of cor- 
responding design and construction. When changes are 
made in the design of a safety or safety relief valve in 
such a manner as to affect the flow path, lift, or performance 
characteristics of the valve, new tests in accordance with 
this Section shall be performed. 

NOTE: See HG-512 for safety and safety relief valve accumulation test 
requirements. See HG-701 for safety and safety relief valve installation 
requirements. 



HG-403 HEATING SURFACE 

The heating surface shall be computed as follows: 

(a) Heating surface, as part of a circulating system in 
contact on one side with water or wet steam being heated 
and on the other side with gas or refractory being cooled, 
shall be measured on the side receiving heat. 

(b) Boiler heating surface and other equivalent surface 
outside the furnace shall be measured circumferentially 
plus any extended surface. 

(c) Waterwall heating surface and other equivalent sur- 
face within the furnace shall be measured as the projected 
tube area (diameter X length) plus any extended surface 
on the furnace side. In computing the heating surface for 
this purpose, only the tubes, fireboxes, shells, tubesheets, 
and the projected area of headers need be considered, 
except that for vertical firetube steam boilers, only that 



Valve capacities are published in "Pressure Relief Device Certifica- 
tions." This publication may be obtained from The National Board of 
Boiler and Pressure Vessel Inspectors, 1055 Crupper Avenue, Columbus, 
OH 43229. 



38 



2007 SECTION IV 



portion of the tube surface up to the middle of the gage 
glass is to be computed. 

(d) When extended surfaces or fins are used, the total 
surface representing the extended surface and its maximum 
designed generating capacity per square foot, as determined 
by the Manufacturer, shall be recorded in the remarks 
section of the Manufacturer's Data Report. Also, the com- 
puted extended surface and the related generating capacity 
per square foot shall be included in the stamping or name- 
plate as shown in Fig. HG-530.2 and Fig. HG-530.3. The 
generating capacity attributed to the extended heating sur- 
face shall be included in the total minimum relief valve 
capacity marked on the stamping or nameplate. 



HG-405 TEMPERATURE AND PRESSURE 
SAFETY RELIEF VALVES 

The thermal sensing elements for temperature and pres- 
sure safety relief valves shall be so designed and con- 
structed that they will not fail in any manner that could 
obstruct flow passages or reduce capacities of the valves 
when the elements are subjected to saturated steam temper- 
ature corresponding to capacity test pressure. Temperature 
and pressure safety relief valves incorporating these ele- 
ments shall comply with a nationally recognized standard. 3 



3 An example of a nationally recognized standard is ANSI Z21.22/ 
CSA 4.4, Relief Valves for Hot Water Supply Systems. 



39 



2007 SECTION IV 



ARTICLE 5 
TESTS, INSPECTION, AND STAMPING 



HG-500 PROOF TESTS TO ESTABLISH 

DESIGN PRESSURE 
HG-501 GENERAL 

(a) The design pressure for pressure parts of boilers for 
which the strength cannot be computed with a satisfactory 
assurance of accuracy shall be established in accordance 
with the requirements of this paragraph, using one of the 
test procedures applicable to the type of loading and to the 
material used in its construction. 

(b) The tests in these paragraphs may be used only for 
the purpose of establishing the design pressure of those 
elements or component parts for which the thickness cannot 
be determined by means of the design rules given in the 
Code. The design pressure of all other elements or compo- 
nent parts shall not be greater than that determined by 
means of the applicable design rules. 

HG-501.1 Types of Tests. Provision is made for two 
types of tests for determining the internal design pressure: 

(a) tests based on yielding of the part to be tested; these 
tests are limited to materials with a ratio of minimum 
specified yield to minimum specified ultimate strength of 
0.625 or less. If a proof tested part shows no evidence of 
permanent yielding per HG-502.1 and HG-502.2, it may 
be Code stamped. 

(b) tests based on bursting of the part. The part proof 
tested under the burst test provisions shall not be Code 
stamped. 

HG-501.2 Retests. A retest shall be allowed on a dupli- 
cate pressure part if errors or irregularities are obvious in 
the test results. 

HG-501.3 Precautions. Safety of testing personnel 
should be given serious consideration when conducting 
proof tests, and particular care should be taken during the 
conducting of bursting tests per HG-502.3. 

HG-501. 4 Pressure Application 

(a) Previously Applied. The pressure parts for which 
the design pressure is to be established shall not previously 
have been subjected to a pressure greater than \\ times 
the desired or anticipated design pressure. 

(b) Application. In the procedures given in HG-502.1 
for the strain measurement test and HG-502.2 for the dis- 
placement measurement test, the hydrostatic pressure in 



the pressure part shall be increased gradually until approxi- 
mately one-half the anticipated design pressure is reached. 
Thereafter, the test pressure shall be increased in steps of 
approximately one-tenth or less of the anticipated design 
pressure until the pressure required by the test procedure 
is reached. The pressure shall be held stationary at the 
end of each increment for a sufficient time to allow the 
observations required by the test procedure to be made and 
shall be released to zero to permit determination of any 
permanent strain or displacement after any pressure incre- 
ment that indicates an increase in strain or displacement 
over the previous equal pressure increment. 

HG-501.5 Critical Areas. As a check that the measure- 
ments are being taken on the most critical areas, the Inspec- 
tor may require a lime wash or other brittle coating to be 
applied on all areas of probable high stress concentrations 
in the test procedures given in HG-502.1 and HG-502.2. 
The surfaces shall be suitably clean before the coating 
is applied in order to obtain satisfactory adhesion. The 
technique shall be suited to the coating material. 

NOTE: Strains should be measured as they apply to membrane stresses. 
In regard to bending stresses it is recognized that high localized and 
secondary stresses may exist in pressure parts designed and fabricated 
in accordance with these rules. Insofar as practical, design rules for details 
have been written to hold such stresses at a safe level consistent with 
experience. 

HG-501.6 Yield Strength and Tensile Strength. For 

proof tests based on yielding, HG-502.1 and HG-502.2, 
the yield strength (or yield point for those materials that 
exhibit that type of yield behavior indicated by a "sharp- 
kneed" portion of the stress-strain diagram) of the material 
in the part tested, shall be determined in accordance with 
the method prescribed in the applicable material specifica- 
tion and as described in ASTM E 8, Tension Testing of 
Metallic Materials. For proof tests based on bursting, 
HG-502.3, the tensile strength instead of the yield strength 
of the material in the part tested shall be similarly deter- 
mined. 

(a) Yield or tensile strength so determined shall be the 
average from three or four specimens cut from the part 
tested after the test is completed. The specimens shall be 
cut from a location where the stress during the test has not 
exceeded the yield strength. The specimens shall not be 



40 



2007 SECTION IV 



oxygen cut because this might affect the strength of the 
material. If yield or tensile strength is not determined by 
test specimens from the pressure part tested, alternative 
methods are given in HG-502.1, HG-502.2, and HG-502.3 
for evaluation of proof test results to establish the design 
pressure. 

(b) When excess stock from the same piece of wrought 
material is available the test specimens may be cut from 
this excess stock. The specimens shall not be removed by 
flame cutting or any other method involving sufficient heat 
to affect the properties of the specimen. 

HG-502 PROCEDURE 

HG-502.1 Strain Measurement Test 

(a) Subject to limitations of HG-501.1(a), this proce- 
dure may be used for pressure parts under internal pressure, 
constructed of any material permitted to be used under the 
rules of Section IV. Strains shall be measured in the direc- 
tion of the maximum stress at the most highly stressed 
parts (see HG-501.5) by means of strain gages of any type 
capable of indicating strains to 0.00005 in. /in. (0.005%). 
Pressure shall be applied as provided in HG-501.4(b). 

(b) After each increment of pressure has been applied, 
readings of the strain gages and the hydrostatic pressure 
shall be taken and recorded. The pressure shall be released 
and any permanent strain at each gage shall be determined 
after any pressure increment that indicates an increase in 
strain for this increment over the previous equal pressure 
increment. Only one application of each increment of pres- 
sure is required. 

(c) Two curves of strain against test pressure shall be 
plotted for each gage line as the test progresses, one show- 
ing the strain under pressure and one showing the perma- 
nent strain when the pressure is removed. The test may be 
discontinued when the test pressure reaches the value H 
that will, by the formula, justify the desired working pres- 
sure, but shall not exceed the pressure at which the plotted 
points for the most highly strained gage line reaches the 
value given below for the material used: 

(1) 0.2% permanent strain for carbon, low alloy, and 
high alloy steels 

(2) 0.5% strain under pressure for copper-base alloys 

(d) The design pressure P for parts tested under this 
paragraph shall be computed by one of the following for- 
mulas: 

(1 ) if the average yield strength is determined by 
HG-501.6, 

Y. 
P = 0.5// -*- 

* a 

(2) if the actual average yield strength is not deter- 
mined by test specimens, 

P = 0.4// 



where 

H = hydrostatic test pressure at which the test was 

stopped in accordance with HG-502. 1(c) 
Y a = actual average yield strength from test specimens 
Y s = specified minimum yield strength 

HG-502.2 Displacement Measurement Test 

(a) Subject to the limitations of HG-501 .1(a), this proce- 
dure may be used only for pressure parts under internal 
pressure, constructed of materials having a definitely deter- 
minable yield point. Displacement shall be measured at 
the most highly stressed parts (see HG-501.5) by means 
of measuring devices of any type capable of measuring to 
1 mil (0.025 mm). This displacement may be measured 
between two diametrically opposed reference points in a 
symmetrical structure, or between a reference point and a 
fixed base point. Pressure shall be applied as provided in 
HG-501. 4(b). 

(b) After each increment of pressure has been applied, 
readings of the displacement and the hydrostatic pressure 
shall be taken and recorded. The pressure shall be released 
and any permanent displacement shall be determined after 
any pressure increment that indicates an increase in mea- 
sured displacement for this increment over the previous 
equal pressure increment. Only one application of each 
increment is required. Care must be taken to insure that 
the readings represent only displacements of the parts on 
which measurements are being made and do not include 
any slip of the measuring devices or any movement of the 
fixed base points or of the pressure part as a whole. 

(c) Two curves of displacement against test pressure 
shall be plotted for each reference point as the test prog- 
resses, one showing the displacement under pressure, and 
one showing the permanent displacement when the pres- 
sure is removed. The application of pressure shall be 
stopped when it is evident that the curve through the points 
representing displacement under pressure has deviated 
from a straight line. 

(d) The pressure coincident with the proportional limit 
of the material shall be determined by noting the pressure at 
which the curve representing displacement under pressure 
deviates from a straight line. The pressure at the propor- 
tional limit may be checked from the curve of permanent 
displacement by locating the point where the permanent 
displacement begins to increase regularly with further 
increases in pressure. Permanent deformation at the begin- 
ning of the curve that results from the equalization of 
stresses and irregularities in the material may be disre- 
garded. 

The design pressure P at test temperature for parts tested 
under this paragraph shall be computed by one of the 
following formulas. 



41 



2007 SECTION IV 



(1) If the average yield strength is determined by 
HG-501.6, 

P = 0.5Hy- 

* a 

(2) In order to eliminate the necessity of cutting ten- 
sile specimens and determining the actual yield strength 
of the material under test, one of the following formulas 
may be used to determine the design pressure: 

(a) for carbon steel, meeting an acceptable Code 
specification, with a specified minimum tensile strength of 
not over 70,000 psi (480 MPa), 



(U.S. Customary Units) 

P = 0.5// 



S + 5,000 



(2a) 



(SI Units) 



P = 0.5// 



S + 34 500 



(2a) 



(b) for any acceptable material listed in Section IV, 



P = 0.4// 



(2b) 



where 



H = hydrostatic test pressure coincident with the pro- 
portional limit of the weakest element of the com- 
ponent part tested 

S = specified minimum tensile strength 

Y a = actual average yield strength from test specimens 

Y s = specified minimum yield strength 

(e) When Formula (2a) or (2b) is used, the material in 
the pressure part shall have had no appreciable cold work- 
ing or other treatment that would tend to raise the yield 
strength above the normal. 

HG-502.3 Bursting Tests 

(a) This procedure may be used for pressure parts under 
internal pressure when constructed of any material permit- 
ted to be used under the rules of Section IV. The design 
pressure of any component part proof tested by this method 
shall be established by a hydrostatic test to failure by 
rupture of a full-size sample of such pressure part. As an 
alternative, the hydrostatic test may be stopped when the 
test pressure reaches a value that will, by the formula in 
(b) below, justify the design pressure. 

(b) The design pressure P, psi, for parts tested under 
this paragraph shall be computed by the following formula: 





p = t x c — r 

5 S a or S m 


where 




B = 


bursting test pressure 



S = specified minimum tensile strength 
S a = average actual tensile strength of test specimens, 
5 m = maximum tensile strength of range of specifi- 
cation 

HG-502.4 Brittle Coating Test Procedure 

(a) Subject to the limitations of HG-501 .1(a), this proce- 
dure may be used only for boiler and boiler parts under 
internal pressure, constructed of materials having a defi- 
nitely determinable yield point. The component parts that 
require proof testing shall be coated with a lime wash or 
other brittle coating in accordance with HG-501. 5. Pressure 
shall be applied in accordance with HG-501. 4. The parts 
being proof tested shall be examined between pressure 
increments for signs of yielding as evidenced by flaking 
of the brittle coating, or by the appearance of strain lines. 
The application of pressure shall be stopped at the first 
sign of yielding, or if desired, at some lower pressure. 

(b) The design pressure P for parts tested under this 
paragraph shall be computed by one of the following for- 
mulas: 

(1) if the average yield strength is determined in 
accordance with HG-501.6, 

P = 0.5// y~ 

(2) to eliminate the necessity of cutting tensile speci- 
mens and determining the actual yield strength of the mate- 
rial under test, one of the following formulas may be used 
to determine the design pressure: 

(a) for carbon steel meeting an acceptable Code 
specification, with a specified minimum tensile strength of 
not over 70,000 psi (480 MPa), 



(U.S. Customary Units) 

P = 0.5// 



(SI Units) 



P = 0.5// 



S + 5,000 



5 + 34 500 



(2a) 



(2a) 



(b) for any acceptable material listed in Section IV, 



P = 0.4// 



(2b) 



where 



H = hydrostatic test pressure at which the test was 

stopped 
S = specified minimum tensile strength 
Y a = actual average yield strength from test specimens 
Y s = specified minimum yield strength 

(c) When Formula (2a) or (2b) is used, the material in 
the pressure part shall have had no appreciable cold work- 
ing or other treatment that would tend to raise the yield 
strength above the normal. 



42 



2007 SECTION IV 



HG-503 TESTS OF PARTS SUBJECT TO 
COLLAPSE 

Parts of the boiler normally subject to collapse for which 
specified rules are not provided in this Section shall with- 
stand without excessive deformation a hydrostatic test of 
not less than three times the desired design pressure. 



HG-504 TESTS OF DUPLICATE PARTS 

When the design pressure of a pressure part has been 
established by a proof test, duplicate parts of the same 
materials, design, and construction need not be proof tested 
but shall be given the standard hydrostatic test at 1 \ times 
the maximum allowable working pressure. The dimensions 
and minimum thickness of the structure to be tested should 
not vary materially from those actually used. A geometri- 
cally similar part may be qualified by a series of tests 
covering the complete size range of the pressure part. 



HG-505 TEST GAGES 

{a) An indicating gage shall be connected directly to 
the pressure part. Intermediate pipe and fittings may be 
used provided there are no intervening valves. If the indi- 
cating gage is not readily visible to the operator controlling 
the pressure applied, an additional indicating gage shall be 
provided where it will be visible to the operator throughout 
the duration of the test. For large pressure parts, it is recom- 
mended that a recording gage be used in addition to indicat- 
ing gages. 

(b) Dial indicating pressure gages used in testing shall 
be graduated over a range of about double the intended 
maximum test pressure, but in no case shall the range be 
less than 1 \ nor more than 4 times that pressure. Digital 
reading pressure gages having a wider range of pressure 
may be used provided the readings give the same or greater 
degree of accuracy as obtained with dial pressure gages. 

(c) All gages used in proof testing shall be calibrated 
against a standard deadweight tester or a calibrated master 
gage before the proof test is begun. Gages shall be recali- 
brated at any time that there is reason to believe they are 
in error. 



HG-506 INSPECTION OF PROOF TESTS 

Tests to establish the design pressure of pressure parts 
shall be witnessed and accepted by an Authorized 
Inspector. 



07 HG-510 



HYDROSTATIC TESTS 



(a) Cast iron boilers shall be tested in accordance with 
HC-410. 



(b) For boilers with integrally finned tubes and a design 
pressure of 160 psi (1.1 MPa), both the pneumatic test 
required in HF-204.1(e) and the hydrostatic test of 
HG-5 10(c) may be alternatively met by a hydrostatic test 
on the boiler under the following conditions: 

(1) A hydrostatic test pressure of at least 240 psi 
(1.9 MPa) is applied to the tubes and boiler. 

(2) A hold time of 5 min is maintained on the boiler 
at the required internal test pressure. 

(3) The test pressure may then be reduced to maxi- 
mum allowable working pressure for inspection. 

(4) The tubes must be readily visible for inspection 
while under pressure. 

(c) All other boilers shall be subjected to a hydrostatic 
test pressure that is not less than the greater of 60 psi 
(0.400 MPa) or 1 \ times the design pressure, except if a 
boiler made of material in Part HF has its maximum allow- 
able working pressure limited by a Part HC cast iron part 
the test pressure may be extended to l\ times the design 
pressure of the cast iron part or 1 \ times the design pressure 
of the next limiting part, whichever is less. 

Close visual inspection is not required during this stage. 
The hydrostatic test pressure may then be reduced to the 
maximum allowable working pressure to be stamped on 
the boiler and maintained at this pressure while close visual 
inspection for leakage is made of all joints and connections. 
In making hydrostatic pressure tests, the pressure shall be 
under such control that the test pressure established shall 
not be exceeded by more than 10 psi (70 kPa). 



HG-512 SAFETY AND SAFETY RELIEF 

VALVE ACCUMULATION TESTS 

If the safety valve or safety relief valve capacity cannot 
be computed or if it is desirable to prove the computations, 
it may be checked in any one of the following ways and, 
if found insufficient, additional capacity shall be provided 

(a) by making an accumulation test, that is, by shutting 
off all discharge outlets from the boiler and forcing the 
fires to the maximum, the safety valve equipment shall be 
sufficient to prevent an excess pressure beyond that speci- 
fied in HG-400.1(f) and HG-400.2(f). 

( b) by measuring the maximum amount of fuel that can 
be burned, and computing the corresponding evaporative 
capacity upon the basis the heating value of the fuel. (See 
B-100, B-101, and B-102.) 



HG-515 INSPECTION TESTS AND 

CERTIFICATION OF BOILERS 
HG-515.1 General. The inspection and testing of boil- 
ers to be marked with the Code H Symbol shall conform 
to the general requirements for inspection and testing in 



43 



2007 SECTION IV 



the following paragraphs and, in addition, to the specific 
requirements for inspection and tests given in Parts HF 
and HC. 

HG-515.2 Manufacturer's Responsibility. The Man- 
ufacturer has the responsibility of providing the Inspector 
with all specified information and of assuring that the qual- 
ity control, the detailed examination, and the tests required 
by this Section are performed at the stages of construction 
necessary to permit them to be meaningful (see F- 202.5). 
These responsibilities shall include, but not be limited to, 
providing or making available for review the following: 

(a) the Certificate of Authorization from the ASME 
Boiler and Pressure Vessel Committee authorizing the 
Manufacturer to fabricate the type of boiler being con- 
structed (see HG-540) 

(b) the drawings and design calculations for the boiler 
or part (see Part HG, Article 3; Part HF, Article 3; Subpart 
HW, Article 7; Subpart HB, Article 1300; and Part HC, 
Article 3) 

(c) identification for all materials used in the fabrication 
of the boiler or part (see Part HG, Article 2; Subpart HW, 
Article 5; Subpart HB, Article 1 100; and Part HC, Article 2) 

(d) any Partial Data Reports when required (see 
HG-531) 

(e) access for the Inspector to those parts of the plant 
concerned with the supply or fabrication of materials for 
the boiler; keeping the Inspector informed of the progress 
of the work so that the required inspections can be per- 
formed in the proper sequence (see HW-900, HB-1500, 
and F-202.5) 

(f) evidence of examination of all material before and 
during fabrication to make certain it has the required thick- 
ness, has no unacceptable defects, is one of the acceptable 
materials permitted by this Section, and that traceability 
to the material identification has been maintained (see 
HG-201, HC-502.5, F-202.4, and HF-210) 

(g) concurrence of the Inspector for correction of non- 
conformities in accordance with the Quality Control Sys- 
tem (see F-202.6) 

(h) evidence of qualification of the welding and /or braz- 
ing procedures before they are used in fabrication (see 
HW-610, HB-1001, HB-1202, and F-202.7) 

(i) evidence of qualification of all welders, welding 
operators, or brazers before the welders, welding operators, 
or brazers are used in production work, except that perform- 
ance qualification by radiography, in conformance with 
Section IX, QW-304 for welders or QW-305 for welding 
operators, may be performed within the first 3 ft (1 m) of 
the first production weld (see HW-401, HW-610, HB-1001, 
HB-1202, and F-202.7) 

(j) records of examination of parts prior to joining to 
make certain that they have been properly fitted for welding 
or brazing and that the surfaces to be joined have been 



cleaned and the alignment tolerances are maintained (see 
Subpart HW, Article 8; Subpart HB, Article 14; and 
F-202.7) 

(k) records of examination of parts as fabrication prog- 
resses for material marking, that surface defects are not 
evident, and that dimensional geometries are maintained 
(see HG-515.1; HF-210; Subpart HW, Article 8; HC-200; 
HC-502.5; and HC-502.6) 

(/) subjecting the boiler to the required hydrostatic test 
(see HG-510) 

(m) affixing the required stamping and/or nameplate to 
the boiler and making certain it is affixed to the proper 
boiler (see HG-530) 

(n) preparing the required Manufacturer's Data Report 
and having it certified by the Inspector (see HG-520) for 
boilers and boiler parts constructed of wrought materials, 
and having it certified by a Certified Individual (see 
HC-502.12); if constructed of cast material (see HC-403) 

(o) providing for retention of Manufacturer's Data 
Reports [see HG-520. 1(b), HC-403, and HC-502.10] 

(p) the Certificates of Conformance for cast iron boiler 
sections (see HC-520) 

HG-515.3 Inspection by Authorized Inspector 

(a) Except as otherwise permitted by Part HC, the 
inspection required by this Section shall be by an Inspector 
employed by an ASME Accredited Authorized Inspection 
Agency, 1 that is, the inspection organization of a state or 
municipality of the United States, a Canadian province, or 
of an insurance company authorized to write boiler and 
pressure vessel insurance. These Inspectors shall have been 
qualified by written examination under the rules of any 
state of the United States or province of Canada that has 
adopted the Code. 

(b) The Inspector shall make all inspections specifically 
required of him plus such other inspections as he believes 
are necessary to enable him to certify that all boilers and 
boiler parts constructed of wrought material that he autho- 
rizes to be stamped with the Code Symbol have been 
designed and constructed in accordance with the require- 
ments of this Code Section. The required inspections and 
verifications shall include, but not be limited to, the fol- 
lowing: 

(1) checking to see that the Manufacturer has a valid 
Certificate of Authorization (see HG-540) and is working 
to the quality control system accepted by the Society (see 
HG-540. 1) 

(2) checking to see that the design calculations, draw- 
ings, specifications, procedures, records, and test results 
are available (see HG-300, HG-200, HG-500, HF-200, and 
HVV-700) 



1 Whenever Authorized Inspection Agency or AIA is used in this 
Code, it shall mean an ASME Accredited Authorized Inspection Agency 
accredited by ASME in accordance with the latest edition of QAI-1. 



44 



2007 SECTION IV 



(3) checking to see that material used in the construc- 
tion of the boiler and parts complies with the requirements 
(see HG-200, HF-200, and HB-1100) 

(4) checking to see that all welding procedures have 
been qualified (see HW-910) 

(5) checking to see that all welders and welding oper- 
ators have been qualified (see HW-911) 

(6) checking to see that all brazing procedures have 
been qualified (see HB-1501) 

(7) checking to see that all brazer and brazer operators 
have been qualified (see HB-1502) 

(8) checking to see that the proper joint factor is used 
for brazed joints that can only be inspected from one side 
(blind joint) (see HB- 1503) 

(9) checking to see that material imperfections 
repaired by welding were acceptably repaired (see HW-830 
and HB-1402) 

(10) visual inspection of boiler parts to confirm that 
the material identification numbers have been properly 
transferred (see HF-210) 

(11) witnessing of proof tests conducted to establish 
the maximum allowable working pressure of boilers (see 
HG-500) 

(12) inspecting each boiler and water heater during 
construction and after completion (see HG-515.3) 

(13) performing internal and external inspections and 
witnessing hydrostatic tests (see HG-510) 

(14) verifying that stamping and /or nameplate is 
proper and that it has been stamped and /or attached to the 
proper boiler (see HG-530 through HG-533) 

(75) signing the certificate of inspection on the Manu- 
facturer' s Data Report when the boiler or part is complete 
and in compliance with all the provisions of this Section 
(see HG-532.3, HG-533.6, and HG-520.2) 

HG-515.4 Duty of Authorized Inspector 

(a) Each boiler shall be inspected during construction 
and after completion and, at the option of the Authorized 
Inspector, at such other stages of the work as he may 
designate. For specific requirements, see the applicable 
parts of this Section. Each Manufacturer or assembler is 
required to arrange for the services of Authorized Inspec- 
tors (see HG-515.2) to perform such inspections on all of 
this work within the scope of this Section, whether per- 
formed in the shop or in the field. 

(b) When multiple, duplicate boiler fabrication makes 
it impracticable for the Inspector to personally perform 
each of his required duties, the Manufacturer, in collabora- 
tion with the Inspector, shall prepare an inspection and 
quality control procedure setting forth in complete detail 
the method by which the requirements of this Section shall 
be maintained (see HG-515 for summaries of the responsi- 
bilities of the Manufacturer and the duties of the Inspector). 
This procedure shall be included in the Manufacturer's 



written Quality Control System (see HG-540). This proce- 
dure shall be submitted to, and shall have received the 
acceptance of, the inspection agency. It shall then be sub- 
mitted by the inspection agency for written acceptance by 
the legal jurisdiction concerned and by an ASME Designee. 
The inspection procedure shall be used in the plant of the 
named Manufacturer by the inspection agency submitting 
it, and shall be carried out by an Inspector in the employ 
of that inspection agency. Any changes in this inspection 
and Quality Control Procedure that affect the requirements 
of this Section are subject to review and acceptance by 
the parties required for a joint review. The joint reviews 
required by HG-540 shall include an ASME Designee. The 
Data Report for a multiple duplicate boiler shall include 
under "Remarks," the statement "Constructed under the 
provisions of HG-5 15.4(b)." 



HG-520 MASTER AND PARTIAL DATA 
REPORTS 

HG-520.1 Manufacturer's Master Data Report. 

Each manufacturer of heating boilers of wrought materials 
to which the Code H Symbol is to be applied shall compile 
a Manufacturer's Data Report for each boiler he produces, 
except that an individual Manufacturer's Data Report may 
be used to include the serial numbers in uninterrupted 
sequence of identical boilers completed, inspected, and 
stamped in a continuous 8 hr period. Form H-2 or H-3 
shall be used. 

(a) The boiler Manufacturer shall have the responsibil- 
ity of furnishing a copy of the completed Manufacturer's 
Data Report at the place of installation to the inspection 
agency, the purchaser, and the state, municipal, or provin- 
cial authority. 

(b) The Manufacturer shall either keep a copy of the 
Manufacturer's Data Report on file for at least 5 years, or 
the boiler may be registered and the original Data Report 
filed with the National Board of Boiler and Pressure Vessel 
Inspectors, 1055 Crupper Avenue, Columbus, Ohio 43229 

HG-520.2 Partial Data Reports 

(a) Manufacturer's Partial Data Reports for those parts 
of a boiler requiring inspection under this Code, which 
are furnished by other than the shop of the manufacturer 
responsible for the completed boiler, shall be executed by 
the parts manufacturer and shall be forwarded in duplicate 
to the manufacturer of the finished boiler. 

(b) Partial Data Reports (Form H-4) shall be completed 
for all parts that require inspection under this Code that are 
fabricated by a manufacturer other than the manufacturer of 
the completed boiler. These Partial Data Reports, together 
with his own inspection, shall be the final Authorized 
Inspector's authority to witness the application of the Code 
Symbol to the completed boiler. 



45 



2007 SECTION IV 



FIG. HG-530.1 OFFICIAL SYMBOL FOR STAMP 

TO DENOTE THE AMERICAN SOCIETY OF 

MECHANICAL ENGINEERS' STANDARD 




HG-520.3 Supplementary Sheet. Form H-6, Manufac- 
turer' s Data Report Supplementary Sheet, shall be used to 
record additional data where space was insufficient on 
a Data Report Form. This Manufacturer's Data Report 
Supplementary Sheet will be attached to the Manufactur- 
er's Data Report Form where used. If Form H-6 is used 
in conjunction with Form H-5, the Authorized Inspector's 
certification is not applicable. 



HG-530 STAMPING OF BOILERS 
07 HG-530.1 Stamping Requirements for Boilers Other 
Than Those Constructed Primarily of Cast Iron or Cast 
Aluminum (See HG-530.2) 

(a) All boilers to which the Code Symbol is to be applied 
shall be built according to the rules of this Section by a 
manufacturer who is in possession of a Code Symbol Stamp 
and a valid Certificate of Authorization. Each boiler shall 
be stamped with the Code Symbol shown in Fig. HG-530. 1 
and with the following data: 

(1) the boiler manufacturer's name, preceded by the 
words "Certified by" 

(2) maximum allowable working pressure 

(3) safety or safety relief valve capacity (minimum), 
as determined according to HG-400.1(d) and HG-400.2(d) 

(4) heating surface, as determined according to 
HG-403 (or power input for electric boilers) 

(5) manufacturer's serial number 

(6) year built 

(7) maximum water temperature 

NOTE: The year built may be incorporated into the serial number as a 
prefix consisting of the last two digits of the year. 

(b) Items (1) through (7) listed in (a) above, with the 
markings arranged substantially as shown in Fig. HG-530.2 
or Fig. HG-530.3, shall be stamped with letters at least 
% 6 in. (8 mm) high [except as permitted in HG-530. 1(d)] 
and in some conspicuous place on the boiler proper or on 
a nameplate at least %4 in. (1.2 mm) thick permanently 
fastened to the boiler proper. The location of the stamping 
shall be as follows: 

(1) Horizontal Tubular Flue Type Boilers: on the 
front head above the central rows of tubes or flues. 



FIG. HG-530.2 STEAM AND WATER BOILERS 

FORM OF STAMPING ON COMPLETED BOILERS OR 

THEIR NAMEPLATES 

(Not Applicable for Boilers Constructed 

Primarily of Cast Iron) 



07 



Certified by 



T T / (Name of Manufacturer) 

I 1 MAWP, Steam — 

■*• ■*■ * 1 MAWP, Water 

1 Maximum Water Temp. 

2 Heating surface boiler 

3 Heating surface water wall 

3 Heating surface extended 

3,4 Ext HS generating cap 



Minimum relief valve capacity 

Manufacturer's serial no. 

5 Year built 



GENERAL NOTE: Acceptable abbreviations to any of the stamp 
wording may be used. 

NOTES: 

(1) For steam only boilers, MAWP Water and Maximum Water 
Temperature markings are optional. 

(2) Kilowatt power input for electric boilers. 

(3) List each type of surface separately. May be omitted if type heating 
surface is not present. 

(4) Generating capacity for extended heating surface Csee HG-403(d)l 

(5) May be omitted when year built is prefix to serial number (see 
HG-530.1). 



(2) Locomotive Firebox, Compact, or Vertical Fire- 
tube Type Boilers: over or near the fire door or handhole 
or washout plug opening on the front end or side. 

(3) Watertube Type Boilers: on a head of the top 
outlet drum. Waterwalls and headers shall carry identifying 
markings. 

(4) Split-Section and Section Firebox Type Wrought 
Boilers: over or near the fire door or handhole or washout 
plug opening on the front end or side. Each section shall 
carry identifying markings. 

(5) Scotch Type Boilers: on either side of the shell 
near the normal water level line adjacent to the front tube- 
sheet. 

(c) On any of the above type boilers where there is not 
sufficient space in the places designated and on other types 
and new designs of boilers, the nameplate shall be located 
in a conspicuous place. 

( d) When there is insufficient space for the nameplate 
required above, smaller letter dimensions may be used, 
provided 

(1) stamping shall be as required in HG-530. 1(a) and 
(b) above, and 



46 



2007 SECTION IV 



FIG. HG-530.3 BOILERS SUITABLE FOR 
WATER ONLY 

FORM OF STAMPING ON COMPLETED BOILERS OR 
THEIR NAMEPLATES 



FIG. HG-530.4 STEAM AND WATER BOILERS 

FORM OF DATA CAST ON CAST IRON BOILER 
SECTIONS 



07 



(Not Applicable for Boilers Constructed 
Primarily of Cast Iron) 




( 


"* )-. Certified by 

TJ ] «> 


(5) 


Certified by 




I Name of Manufacturer 
_^j MAWP Steam 


for 


111/ (Name of Manufacturer) 
II 1 MAWP r Water 


MAWP ; Water 
(3) 


(2) 


( 1 1 \ 

V_- yJ 1 Maximi]m Water Temp. 


V— — ' 

2 Heating surface hniler 
3 Heating surface water wall 
3 Heating surface extended 
3 ' 4 Fxt HS generating nap 


(Pattern number) 
(4) 




(Casting date) 




NOTE: 


(1) through (5) refer to HG-530. 2(a)(1)- 


(a)(5); (5) is 


Manufacturer's serial nn. 


optional 




5 Yearhuilt 





GENERAL NOTE: Acceptable abbreviations to any of the stamp 
wording may be used. 

NOTES: 

(1) For steam only boilers, MAWP Water and Maximum Water 
Temperature markings are optional. 

(2) Kilowatt power input for electric boilers. 

(3) List each type of surface separately. May be omitted if type heating 
surface is not present. 

(4) Generating capacity for extended heating surface [see HG-403(d)l 

(5) May be omitted when year built is prefix to serial number (see 
HG-530. 1). 

(2) character size shall be no smaller than % 2 m - 
(4 mm) 

(e) The stamping or nameplate on the boiler proper shall 
not be covered with insulating or other material unless 

(1) the required markings are duplicated and stamped 
directly on the boiler casing in some conspicuous place 
using letters and numerals at least \§ in. (8 mm) high 

(2) an opening with a removable cover is provided 
in the jacket or other form of casing so that, when removed, 
the stamping or nameplate on the boiler proper can be 
viewed 

(3) the required data are duplicated by stamping or 
marking with letters at least \ in. (3 mm) high on a nonfer- 
rous nameplate at least 3 in. X 4 in. (75 mm x 100 mm) 
size and permanently attaching the nameplate to the casing 
in some conspicuous place by mechanical means or by an 
adhesive system meeting the requirements of Appendix 3 

(f) The Code Symbol may be preapplied to a nameplate. 
The nameplate may be attached to the boiler after the 
final fabrication and examination sequence but before the 
hydrostatic test, provided the procedure for sequence of 
stamping is described in the manufacturer's accepted qual- 
ity control system. The Code Symbol and manufacturer's 



data may be stamped, etched, cast, or impressed thereon. 
(g) The ASME Code Symbol Stamp(s) shall not be used 
by an organization to which it was not issued. 

HG-530.2 Marking Requirements for Cast Iron or 
Cast Aluminum Boilers 

(a) All boiler parts or sections to which the Code Sym- 
bol is to be applied shall be built according to the rules of 
this Section by a manufacturer 3 who is in possession of a 
Code Symbol Stamp and a valid Certificate of Authoriza- 
tion. Each boiler section, including end and intermediate 
cored sections, shall be cast with the Code Symbol shown 
in Fig. HG-530. 1 and with the following data cast in letters 
or numerals at least \ 6 in. (8 mm) high: 

(1) the boiler or parts manufacturer's 3 name or 
acceptable abbreviation, preceded by the words "Certified 
by:" (or "Cert, by" on cast boiler sections only where space 
for marking is limited; the abbreviation "Cert, by" shall 
not be used on nameplates) 

(2) maximum allowable working pressure 4 

(3) pattern number 

(4) casting date 

(5) the shop assembler' s 5 name or acceptable abbrevi- 
ation (if different from manufacturer) 6 

Arrangement of data cast on sections shall be substan- 
tially as shown in Fig. HG-530.4 for cast iron steam or 
hot water heating boilers or Fig. HG-530.5 for cast iron 
or cast aluminum hot water heating boilers. 



The foundry that casts the boiler parts or sections and that may shop 
assemble. 
4 May be stamped. 

The shop that assembles sections into boilers and that is in possession 
of a Code Symbol Stamp and valid Certificate of Authorization. 
6 Optional. 



07 



47 



2007 SECTION IV 



FIG. HG-530.5 BOILERS SUITABLE FOR WATER 
ONLY 

FORM OF DATA CAST ON CAST IRON BOILER 
SECTIONS 




Certified by 



(1) 



(5) 



Name of Manufacturer 
MAWP, Water 



for 
-(2) 



(3) 



(Pattern number) 
(4) 



(Casting date) 



NOTE: (1) through (5) refer to HG-530.2(a)(l)-(a)(5); (5) is 
optional. 



FIG. HG-530.7 BOILERS SUITABLE FOR WATER 
ONLY 

FORM OF STAMPING ON COMPLETED 
CAST IRON BOILERS OR THEIR NAMEPLATES 




Certified by 



Name of Shop Assembler 



MAWP, Water 
Maximum Water Temp. 

Minimum relief valve capacity 



07 FIG. HG-530.6 STEAM AND WATER BOILERS 

FORM OF STAMPING ON COMPLETED 
CAST IRON BOILERS OR THEIR NAMEPLATES 




Certified by 



Name of Shop Assembler 



MAWP, Steam 
MAWP, Water 
Maximum Water Temp. 

Minimum relief valve capacity 



Other data may be cast on the sections. The marking 
"ASME" or "ASME standard" shall not be used. 

(b) When the boiler size and number of sections have 
been decided, the completed boiler shall be marked with 
the Code Symbol shown in Fig. HG-530.1 and with the 
following data: 

(1) the shop assembler's name preceded by the words 
"Certified by" 

(2) maximum allowable working pressure 

(3) safety or safety relief valve capacity (minimum), 
as determined according to HG-400.1(e) and HG-400.2(d) 

(4) maximum water temperature 

(c) The markings for the completed boiler shall be 
arranged substantially as shown in Fig. HG-530.6 or 
Fig. HG-530.7. 



(d) Data for more than one size boiler in a model series 
may be listed on the nameplate. When different model 
numbers having the same number of sections and jacket 
length have different minimum safety or safety relief valve 
capacities, the highest value shall be listed. The following 
additional information shall be included for each size listed: 

(1) boiler model number 

(2) number of sections 

(3) jacket length 

(4) the statement: "To determine boiler size, count 
the number of sections or measure the jacket length" 

(e) The provisions of (b) above shall be met utilizing 
one of the following methods: 

(1) stamping the required markings on a nonferrous 
nameplate at least 3 in. X 4 in. (75 mm x 100 mm) in 
size and 3 / M in. (1.2 mm) thick using letters and numerals 
at least \ in. (3 mm) high and permanently attaching the 
nameplate to the boiler proper in some conspicuous place. 
The nameplate shall not be covered with insulating or other 
material except that when a jacket or other form of casing 
is applied to a boiler, an opening with a removable cover 
shall be provided for viewing the required stamping. 

(2) stamping the required markings directly into the 
boiler casing in some conspicuous place using letters and 
numerals at least 5 / l6 in. (8 mm) high. 

(3) stamping or marking the required data on a non- 
ferrous or nonmetallic nameplate at least 3 in. x 4 in. 
(75 mm X 100 mm) in size using letters and numerals at 
least \ in. (3 mm) high and permanently attaching the 
nameplate to the casing in some conspicuous place by 
mechanical means or by an adhesive system. The name- 
plate and the adhesive system shall meet the requirements 
of Appendix 3. 



48 



2007 SECTION IV 



Other data may be stamped on the casing or the name- 
plate provided the required markings are distinct and sepa- 
rate from the other data. The marking "ASME" or "ASME 
standard" shall not be used. 

(4) the Code Symbol may be preapplied to a name- 
plate. 
07 (5) the nameplate may be attached to the casing of a 

cast iron or cast aluminum boiler by the Manufacturer or 
shop assembler at a plant other than that shown on his 
Certificate of Authorization provided the plant is owned 
by the Certificate Holder and the nameplate 's control and 
use is addressed in his Quality Control Manual. 

(6) the ASME Code Symbol stamp(s) shall not be 
used by an organization to which it was not issued. 



HG-531 STAMPING OF PARTS AND 
ACCESSORIES 

(a) Parts of boilers for which Partial Data Reports are 
required by HG-520.2 shall be marked with the following: 

(1) the official Code Symbol shown in Fig. HG-530. 1 
above the word "Part" 

(2) the part manufacturer's name 

(3) the part manufacturer's serial number 

(b) No part or accessory of a boiler may be marked 
with the Code Symbol shown in Fig. HG-530. 1 unless so 
specified in the Code. The markings "ASME" or "ASME 
standard" shall not be used. 



HG-532 STAMPING OF FIELD ASSEMBLED 
WROUGHT BOILERS 
HG-532.1 Responsibility of Manufacturer of Boiler 
Unit. When a boiler manufactured of wrought material is 
furnished by one manufacturer and is not assembled and 
subjected to hydrostatic test prior to shipment, the manufac- 
turer of the boiler unit shall compile a Manufacturer's Data 
Report Form H-2 or H-3 recording all items of the complete 
boiler unit. 

HG-532. 2 Execution of Manufacturer's Data 
Report. The Manufacturer's Data Report shall be properly 
executed by the manufacturer and the Authorized Inspec- 
tor, who shall sign the certificate of shop inspection certi- 
fying that each enumerated item that has been inspected 
at the shop conforms to the requirements of the ASME 
Code. The manufacturer in signing each Data Report shall 
state under his signature the expiration date on the Certifi- 
cate of Authorization to use the Symbol. 

HG-532.3 Application of Stamping and Signing Data 
Sheets. Proper stamping as required by HG-530.2 shall be 
applied at the shop and the data sheets shall be signed by 
the same or different Inspectors who shall indicate the 
portions of the inspections made at the shop and in the field. 



HG-533 INSPECTION AND STAMPING OF 
FIELD ASSEMBLED BOILER 
PRESSURE PARTS 
HG-533.1 Authorized Assemblers and Welders. The 

assembly of any parts or subassemblies of the unit that 
requires welding shall be made by one possessing a heating 
boiler stamp. The welding of any parts or subassemblies 
during field assembly shall be done by persons who meet 
the requirements of HW-610. 

HG-533.2 Execution of Data Report Sheet. When the 
assembly is made by anyone other than the manufacturer 
of the boiler unit, the Data Report sheet properly executed 
in accordance with HG-532 shall be forwarded to the 
assembler who shall be responsible for the proper handling 
of the Data Report and who shall fill in such items as are 
not filled in 'at the shop, and sign the Data Sheet as the 
"assembler" or "assembling organization" instead of "man- 
ufacturer." He shall also append, above his signature, the 
statement: "We certify that the field assembly of all parts 
conform with the requirements of the ASME Boiler and 
Pressure Vessel Code." 

HG-533.3 Field Inspection by Authorized Inspector. 

The field inspection shall be made by an Authorized Inspec- 
tor (as defined in HG-515.3) and the Inspector shall make 
such inspections as he believes are needed to enable him 
to certify that the boiler has been constructed in accordance 
with the Code. Properly executed Manufacturer's Data 
Reports, together with the Inspector's own inspection, shall 
constitute his authority to sign the certificate of field 
inspection. 

HG-533.4 Application of Assembler's Stamp. The 

Assembler's H Stamp, together with the assembler's name 
or an acceptable abbreviation, shall be applied in the field 
on the boiler near the stamping called for in HG-530. 1, 
when the assembly is accepted by the Authorized Inspector. 

HG-533.5 Application for H Symbol. Applicants for 
an H Symbol to be used only in the field assembly of 
heating boilers shall so state on the application form, and 
the Certificate of Authorization issued to such applicants 
shall show that the authorization to use the H Symbol is 
limited to the field assembly of welded boilers constructed 
to Section IV (see HG-540). 

HG-533.6 Certificate of Field Inspection. The certifi- 
cate of field inspection on the Data Report shall be executed 
by the Authorized Inspector. The assembler or assembling 
organization shall have the responsibility for forwarding 
and filing of Manufacturer's Data Reports as required by 
HG-520.1(a) and HG-520.1(b). 

HG-533.7 Mechanical Field Assembly. For a boiler 
manufactured of wrought materials that has not been com- 
pleted in the Manufacturer's shop, field assembly involving 
no welding does not need to be performed by a Company 



49 



2007 SECTION IV 



possessing a heating boiler stamp. However, when a boiler 
is not assembled by a stamp holder, the Manufacturer 
assuming responsibility for the completed boiler is respon- 
sible for providing for field inspection by an Authorized 
Inspector employed by the Manufacturer's Authorized 
Inspection Agency, and signature of the Certificate of Field 
Assembly Compliance by a representative of the Manufac- 
turer, after the required hydrostatic test has been completed. 
Application of an assembler H stamp in accordance with 
HG-533.4 is not required. 



HG-534 FIELD-ASSEMBLED CAST IRON 
BOILERS 
HG-534. 1 Hydrostatic Tests. Each individual section 
or boiler part shall be subjected to a hydrostatic test as 
required in HC-410 at the Manufacturer's plant prior to 
shipment. 

HG-534.2 Marking. The marking on cast iron boilers 
shall meet the requirements of HG-530.2. The nameplate 
shall be attached to the casing by the Manufacturer or Shop 
Assembler. 

HG-534.3 Assembly Instructions. The Manufacturer 
shall provide printed instructions for the installer to follow 
when mechanically assembling the boiler, including 
instructions for performing the hydrostatic test of the 
assembled boiler in HC-410. 1 and HC-410.2. 



HG-540 CODE SYMBOL STAMPS 

HG-540.1 Authorization. A Certificate of Authoriza- 
tion to use the Code Symbols H, HLW, and/or HV will 
be granted by the Society pursuant to the provisions of 
the following paragraphs. Stamps for applying the Code 
Symbol shall be obtained from the Society. 

HG-540.2 Application for Certificate of Authori- 
zation 

(a) Any organization desiring a Certificate of Authoriza- 
tion shall apply to the Boiler and Pressure Vessel Commit- 
tee of the Society, on forms issued by the Society, 7 
specifying the Stamp desired and the scope of Code activi- 
ties to be performed. When an organization intends to build 
Code items in plants in more than one geographical area, 
either separate applications for each plant or a single appli- 
cation listing the addresses of all such plants may be sub- 
mitted. Each application shall identify the Authorized 
Inspection Agency providing Code inspection at each plant. 
A separate Certificate of Authorization will be prepared 
and a separate fee charged by the Society for each plant. 



7 The application forms and related information and instructions may 
be obtained by writing to: ASME, Secretary, Boiler and Pressure Vessel 
Committee, Three Park Avenue, New York, NY 10016. 



Each applicant must agree that each Certificate of Autho- 
rization and each Code Symbol Stamp are at all times the 
property of the Society, that they will be used according 
to the rules and regulations of this Section of the Code, 
and that they will be promptly returned to the Society 
upon demand, or when the applicant discontinues the Code 
activities covered by his Certificate, or when the Certificate 
of Authorization has expired and no new Certificate has 
been issued. The holder of a Code Symbol Stamp shall 
not allow any other organization to use it. 

(b) Issuance of Authorization. Authorization to use 
Code Symbol Stamps may be granted or withheld by the 
Society in its absolute discretion. If authorization is 
granted, and the proper administrative fee paid, a Certifi- 
cate of Authorization evidencing permission to use any 
such Symbol, expiring on the triennial anniversary date 
thereafter, will be forwarded to the applicant. Each such 
certificate will identify the Code Symbol to be used, and 
the type of shop and /or field operations for which authori- 
zation is granted (see Appendix K). The Certificate will 
be signed by the Chairman of the Boiler and Pressure 
Vessel Committee and the Director of Accreditation. 

(c) Six months prior to the date of expiration of any 
such Certificate, the applicant must apply for a renewal of 
such authorization and the issuance of a new Certificate. 
The Society reserves the absolute right to cancel or refuse 
to renew such authorization, returning, pro rata, fees paid 
for the unexpired term. 

The Certificate of Authorization for the use of the H, 
HLW, and/or HV Code Symbol Stamp is valid for 3 years; 
the H (cast iron) Certificate of Authorization for the H 
(cast iron) Code Symbol Stamp is valid for one year. 

HG-540.3 Inspection Agreement. As a condition of 
obtaining and maintaining a Certificate of Authorization to 
use the H or HLW Code Symbol Stamps, the Manufacturer 
(except for cast iron heating boilers) must have in force 
at all times an inspection contract or agreement with an 
Authorized Inspection Agency as defined in HG-515.3 to 
provide inspection services. This inspection agreement is 
a written agreement between the Manufacturer and the 
Inspection Agency that specifies the terms and conditions 
under which the inspection services are to be furnished 
and that states the mutual responsibilities of the Manufac- 
turer and the Authorized Inspectors. A Certificate Holder 
shall notify the Society whenever his agreement with an 
Authorized Inspection Agency is cancelled or changed to 
another Authorized Inspection Agency. Manufacturers of 
pressure relief valves are not required to have an inspection 
agreement with an Authorized Inspection Agency. 

A Certificate of Authorization may be granted to a Manu- 
facturer of safety valves to use the safety valve Symbol 
Stamp providing such stamp is applied only to safety valves 
that have been capacity certified in accordance with the 
requirements of this Section. 



50 



2007 SECTION IV 



HG-540.4 Quality Control System. Any Manufacturer 
or Assembler holding or applying for a Certificate of 
Authorization to use the H, HLW, or HV Stamp shall have, 
and demonstrate, a quality control system to establish that 
all Code requirements, including material, design, fabrica- 
tion, examination (by the Manufacturer), inspection of boil- 
ers, vessels, parts (by the Authorized Inspector), pressure 
testing, and certification will be met. The quality control 
system shall be in accordance with the requirements of 
Appendix F, except for Cast Iron Boiler Certificate Hold- 
ers. It must be in accordance with the requirements of 
Article 5 of Part HC. 

HG-540.5 Evaluation for Authorization and Reau- 
thorization. Before issuance or triennial renewal of a Cer- 
tificate of Authorization for use of the H or HLW Stamp, 
the Manufacturer's facilities and organization are subject 
to a joint review by his Inspection Agency and an ASME 
Designee who is selected by the concerned legal jurisdic- 
tion, except that for H (cast iron) the review shall be 
yearly by an ASME Designee selected by ASME. A written 
description or checklist of the quality control system that 
identifies what documents and what procedures the Manu- 
facturer will use to produce a Code item shall be available 
for review. 

The purpose of the review is to evaluate the applicant's 
quality control system and its implementation. The appli- 
cant shall demonstrate sufficient administrative and fabri- 
cation functions of the system to show that he has the 
knowledge and ability to produce the Code items covered 
by his quality control system. Fabrication functions may 
be demonstrated using current work, a mock-up, or a com- 
bination of the two. 

A written report to the Society shall be made jointly by 
the ASME Designee and the Inspection Agency employed 
by the Manufacturer to do his Code inspection. This report 
is then reviewed by the Subcommittee on Boiler and Pres- 
sure Vessel Accreditation, which will either issue a Cer- 
tificate of Authorization or notify the applicant of 
deficiencies revealed by the review. In such a case, the 
applicant will be given an opportunity to explain or correct 
these deficiencies. 

Certificates of Authorization will be endorsed to indicate 
the scope of activity authorized. Authorization may include 
field operations if the review team determines that these 
operations are adequately described in the quality control 
manual, and this determination is accepted by the Society. 

Before issuance or renewal of a Certificate of Authoriza- 
tion for use of the HV stamp, the valve Manufacturer's 
facilities and organization are subject to a review by an 
ASME Designee. A written description or checklist of the 
quality control system, which identifies the documents and 
procedures the Manufacturer will use to produce Code 
safety and safety relief valves, shall be available for review. 
The ASME Designee shall make a written report to the 



Society, where the Subcommittee on Boiler and Pressure 
Vessel Accreditation will act on it as described above. 

Before issuance or renewal of a Certificate of Authoriza- 
tion for use of the H (cast iron) Stamp to produce cast 
iron boilers, each Manufacturer (the foundry who casts the 
boiler parts or sections and who may shop assemble) or 
Assember is subject to review by an ASME Designee. A 
written description or checklist of the quality control sys- 
tem in accordance with the requirements of Part HC shall 
be available for review. The ASME Designee shall make 
a written report to the Society, where the Subcommittee 
on Boiler and Pressure Vessel Accreditation will act on it 
as described above. 

HG-540.6 Authorization of Changes. The Manufac- 
turer may at any time make changes in the quality control 
system concerning the methods of achieving results, sub- 
ject to acceptance by the Authorized Inspector. For Manu- 
facturers of multiple duplicate pressure vessels, 8 
acceptance of these changes by the jurisdiction (if applica- 
ble) and an ASME Designee is also required. For Manufac- 
turers of HV stamped safety and safety relief valves, such 
acceptance shall be by a representative from an ASME- 
designated organization. 

For those areas where there is no jurisdiction, that func- 
tion shall be performed by an ASME Designee selected 
by ASME. Where a jurisdiction does not review a Manufac- 
turer' s facility, that function shall be performed by an 
ASME Designee who is selected by the concerned legal 
jurisdiction. Where the jurisdiction is the Manufacturer's 
Inspection Agency, the joint review and joint report shall 
be made by the jurisdiction and an ASME Designee. 

HG-540.7 Code Construction Before Receipt of Cer- 
tificate of Authorization. When used to demonstrate his 
quality control system, a Manufacturer may start fabricat- 
ing Code items before receipt of a Certificate of Authoriza- 
tion to use a Code Symbol Stamp under the following 
conditions. 

(a) The fabrication is done with the participation of the 
Authorized Inspector and is subject to his acceptance. 

(b) The activity is in conformance with the applicant's 
quality control system. 

(c) The item is stamped with the appropriate Code Sym- 
bol and certified once the applicant receives his Certificate 
of Authorization from the Society. 

HG-540.8 Regulations on Use of Code Symbol 
Stamps. The Boiler and Pressure Vessel Committee may 
at any time make such regulations concerning the issuance 
and use of Code Symbol Stamps as it deems appropriate, 
and all such regulations shall become binding upon the 
holders of any valid Certificates of Authorization. 



See HG-515.4 for additional requirements applicable to multiple, 
duplicate pressure vessel fabrication. 



51 



2007 SECTION IV 



ARTICLE 6 
INSTRUMENTS, FITTINGS, AND CONTROLS 



HG-600 GENERAL 

All instruments, fittings, and controls described in this 
Article shall be installed prior to operation. 



HG-601 FOR STEAM HEATING BOILERS 
HG-602 STEAM GAGES 

(a) Each steam boiler shall have a steam gage or a 
compound steam gage connected to its steam space or to 
its water column or to its steam connection. The gage or 
piping to the gage shall contain a siphon or equivalent 
device that will develop and maintain a water seal that will 
prevent steam from entering the gage tube. The piping 
shall be so arranged that the gage cannot be shut off from 
the boiler except by a cock placed in the pipe at the gage 
and provided with a tee- or lever-handle arranged to be 
parallel to the pipe in which it is located when the cock 
is open. The gage connection boiler tapping, external 
siphon, or piping to the boiler shall not be less than NPS % 
(DN 8). Where steel or wrought iron pipe or tubing is used, 
the boiler connection and external siphon shall be not less 
than NPS V 2 (DN 15). Ferrous and nonferrous tubing hav- 
ing inside diameters at least equal to that of standard pipe 
sizes listed above may be substituted for pipe. 

(b) The scale on the dial of a steam boiler gage shall 
be graduated to not less than 30 psi (200 kPa) nor more 
than 60 psi (414 kPa). The travel of the pointer from psi 
to 30 psi (0 kPa to 200 kPa) pressure shall be at least 3 in. 
(75 mm). 



HG-603 WATER GAGE GLASSES 

(a) Each steam boiler shall have one or more water gage 
glasses attached to the water column or boiler by means 
of valved fittings not less than NPS \ (DN 15), with the 
lower fitting provided with a drain valve of a type having 
an unrestricted drain opening not less than \ in. (6 mm) 
in diameter to facilitate cleaning. Gage glass replacement 
shall be possible with the boiler under pressure. Water 
glass fittings may be attached directly to a boiler. 

Boilers having an internal vertical height of less than 
10 in. (250 mm) may be equipped with a water level 



indicator of the Glass Bull's-Eye type provided the indica- 
tor is of sufficient size to show the water at both normal 
operating and low-water cutoff levels. 

(b) The lowest visible part of the water gage glass shall 
be at least 1 in. (25 mm) above the lowest permissible 
water level recommended by the boiler Manufacturer. With 
the boiler operating at this lowest permissible water level, 
there shall be no danger of overheating any part of the 
boiler. 

Each boiler shall be provided at the time of the manufac- 
ture with a permanent marker indicating the lowest permis- 
sible water level. The marker shall be stamped, etched, or 
cast in metal; or it shall be a metallic plate attached by 
rivets, screws, or welding; or it shall consist of material 
with documented tests showing its suitability as a perma- 
nent marking for the application. This marker shall be 
visible at all times. Where the boiler is shipped with a 
jacket, this marker may be located on the jacket. 

NOTE: Transparent material other than glass may be used for the water 
gage provided that the material will remain transparent and has proved 
suitable for the pressure, temperature, and corrosive conditions expected 
in service. 



(c) In electric boilers of the submerged electrode type, 
the water gage glass shall be so located to indicate the 
water levels both at startup and under maximum steam 
load conditions as established by the manufacturer. 

(d) In electric boilers of the resistance element type, the 
lowest visible part of the water gage shall be located at 
least 1 in. (25 mm) above the lowest permissible water 
level specified by the Manufacturer. Each electric boiler 
of this type shall also be equipped with an automatic low- 
water cutoff on each boiler pressure vessel so located as 
to automatically cut off the power supply to the heating 
elements before the surface of the water falls below the 
visible part of the glass. 

(e) Tubular water glasses on electric boilers having a 
normal water content not exceeding 100 gal (300 1) shall 
be equipped with a protective shield. 

(f) A water level indicator using an indirect sensing 
method may be used in lieu of an operating water gauge 
glass; however, a water gauge glass must be installed and 
operable but may be shut off by valving. The water level 



52 



2007 SECTION IV 



indicator must be attached to a water column or directly 
to the boiler by means of valved fittings not less than NPS 
\ (DN 15). The device shall be provided with a drain valve 
of a type having an unrestricted drain opening not less 
than % in. (6 mm) in diameter to facilitate cleaning. Service 
and replacement of internal parts and/or housing shall be 
possible with the boiler under pressure. 



HG-604 WATER COLUMN AND WATER 
LEVEL CONTROL PIPES 

(a) The minimum size of ferrous or nonferrous pipes 
connecting a water column to a steam boiler shall be NPS 1 
(DN 25). No outlet connections, except for damper regula- 
tor, feedwater regulator, steam gages, or apparatus that 
does not permit the escape of any steam or water except 
for manually operated blowdowns, shall be attached to a 
water column or the piping connecting a water column to 
a boiler (see HG-705 for introduction of feedwater into a 
boiler). If the water column, gage glass, low- water fuel 
cutoff, or other water level control device is connected to 
the boiler by pipe and fittings, no shutoff valves of any 
type shall be placed in such pipe, and a cross or equivalent 
fitting to which a drain valve and piping may be attached 
shall be placed in the water piping connection at every 
right angle turn to facilitate cleaning. The water column 
drain pipe and valve shall be not less than NPS \ (DN 20). 

(b) The steam connections to the water column of a 
horizontal firetube wrought boiler shall be taken from the 
top of the shell or the upper part of the head, and the water 
connection shall be taken from a point not above the center 
line of the shell. For a cast iron boiler, the steam connection 
to the water column shall be taken from the top of an 
end section or the top of the steam header, and the water 
connection shall be made on an end section not less than 
6 in. (150 mm) below the bottom connection to the water 
gage glass. 

HG-605 PRESSURE CONTROL 

Each automatically fired steam boiler shall be protected 
from overpressure by two pressure-operated controls. 

(a) Each individual automatically fired steam boiler 
shall have a safety limit control that will cut off the fuel 
supply to prevent steam pressure from exceeding the 15 psi 
(100 kPa) maximum allowable working pressure of the 
boiler. Each control shall be constructed to prevent a pres- 
sure setting above 15 psi (100 kPa). 

(b) Each individual steam boiler shall have a control 
that will cut off the fuel supply when the pressure reaches 
an operating limit, which shall be less than the maximum 
allowable pressure. 

(c) Shutoff valves of any type shall not be placed in 
the steam pressure connection between the boiler and the 



controls described in (a) and (b) above. These controls 
shall be protected with a siphon or equivalent means of 
maintaining a water seal that will prevent steam from enter- 
ing the control. The control connection boiler tapping, 
external siphon, or piping to the boiler shall not be less 
than NPS \ (DN 8), but where steel or wrought iron pipe 
or tubing is used, they shall not be less than NPS \ (DN 15). 
The minimum size of an external siphon shall be NPS \ 
(DN 8) or \ in. (10 mm) O.D. nonferrous tubing. 



HG-606 AUTOMATIC LOW- WATER FUEL 

CUTOFF AND/OR WATER FEEDING 
DEVICE 

(a) Each automatically fired steam or vapor-system 
boiler shall have an automatic low-water fuel cutoff so 
located as to automatically cut off the fuel supply before 
the surface of the water falls below the lowest visible part of 
the water gage glass. If a water feeding device is installed, it 
shall be so constructed that the water inlet valve cannot 
feed water into the boiler through the float chamber and 
so located as to supply requisite feedwater. 

(b) Such a fuel cutoff or water feeding device may be 
attached directly to a boiler. A fuel cutoff or water feeding 
device may also be installed in the tapped openings avail- 
able for attaching a water glass direct to a boiler, provided 
the connections are made to the boiler with nonferrous tees 
or Y's not less than NPS \ (DN 15) between the boiler 
and the water glass so that the water glass is attached 
directly and as close as possible to the boiler; the run of 
the tee or Y shall take the water glass fittings, and the side 
outlet or branch of the tee or Y shall take the fuel cutoff 
or water feeding device. The ends of all nipples shall be 
reamed to full-size diameter. 

(c) Fuel cutoffs and water feeding devices embodying 
a separate chamber shall have a vertical drain pipe and a 
blowoff valve not less than NPS 3 / 4 (DN 20), located at 
the lowest point in the water equalizing pipe connections 
so that the chamber and the equalizing pipe can be flushed 
and the device tested. 



HG-607 MODULAR STEAM HEATING 
BOILERS 

(a) Each module of a modular steam heating boiler shall 
be equipped with 

(1) steam gage, see HG-602 

(2) water gage glass, see HG-603 

(3) a pressure control that will cut off the fuel supply 
when the pressure reaches an operating limit, which shall 
be less than the maximum allowable pressure 

(4) low water cutoff, see HG-606 

(b) The assembled modular steam boiler shall also be 
equipped with a safety limit control that will cut off the 



53 



2007 SECTION IV 



fuel supply to prevent steam pressure from exceeding the 
15 psi (100 kPa) maximum allowable working pressure of 
the boiler. The control shall be constructed to prevent a 
pressure setting above 15 psi (100 kPa). 

HG-610 FOR HOT WATER HEATING OR 
HOT WATER SUPPLY BOILERS 

HG-611 PRESSURE OR ALTITUDE GAGES 

(a) Each hot water heating or hot water supply boiler 
shall have a pressure or altitude gage connected to it or to 
its flow connection in such a manner that it cannot be shut 
off from the boiler except by a cock with tee or lever 
handle, placed on the pipe near the gage. The handle of 
the cock shall be parallel to the pipe in which it is located 
when the cock is open. 

(b) The scale on the dial of the pressure or altitude gage 
shall be graduated approximately to not less than 1 V 2 nor 
more than 3V 2 times the pressure at which the safety relief 
valve is set. 

(c) Piping or tubing for pressure- or altitude-gage con- 
nections shall be of nonferrous metal when smaller than 
NPS 1 (DN 25). 

HG-612 THERMOMETERS 

Each hot water heating or hot water supply boiler shall 
have a thermometer so located and connected that it shall 
be easily readable. The thermometer shall be so located 
that it shall at all times indicate the temperature of the 
water in the boiler at or near the outlet. 



HG-613 TEMPERATURE CONTROL 

Each automatically fired hot water heating or hot water 
supply boiler shall be protected from over-temperature by 
two temperature-operated controls. 

(a) Each individual automatically fired hot water heat- 
ing or hot water supply boiler shall have a high temperature 
limit control that will cut off the fuel supply to prevent 
water temperature from exceeding its marked maximum 
water temperature at the boiler outlet. This control shall 
be constructed to prevent a temperature setting above the 
maximum. 

(b) Each individual hot water heating or hot water sup- 
ply boiler shall have a control that will cut off the fuel 
supply when the system water temperature reaches a preset 
operating temperature, which shall be less than the maxi- 
mum water temperature. 

HG-614 LOW- WATER FUEL CUTOFF 

(a) Each automatically fired hot water boiler with heat 
input greater than 400,000 Btu/hr (1 17 kW) shall have an 



automatic low-water fuel cutoff that has been designed 
for hot water service, and it shall be so located as to 
automatically cut off the fuel supply when the surface of 
the water falls to the level established in (b) below (see 
Fig. HG-703.2). 

(b) As there is no normal waterline to be maintained in 
a hot water boiler, any location of the low- water fuel cutoff 
above the lowest safe permissible water level established 
by the boiler manufacturer is satisfactory. 

(c) A coil-type boiler or a watertube boiler with heat 
input greater than 400,000 Btu/hr (117 kW) requiring 
forced circulation to prevent overheating of the coils or 
tubes shall have a flow-sensing device installed in lieu of 
the low-water fuel cutoff required in (a) above to automati- 
cally cut off the fuel supply when the circulating flow is 
interrupted. 

(d) A means shall be provided for testing the operation 
of the external low-water fuel cutoff without resorting to 
draining the entire system. Such means shall not render 
the device inoperable except as described as follows. If 
the means temporarily isolates the device from the boiler 
during this testing, it shall automatically return to its normal 
position. The connection may be so arranged that the device 
cannot be shut off from the boiler except by a cock placed 
at the device and provided with a tee or lever-handle 
arranged to be parallel to the pipe in which it is located 
when the cock is open. 

HG-615 MODULAR HOT WATER HEATING 
BOILERS 

(a) Each module of a modular hot water heating boiler 
shall be equipped with 

(1) pressure /altitude gage, see HG-611 

(2) thermometer, see HG-612 

(3) temperature control that will cut off the fuel sup- 
ply when the temperature reaches an operating limit, which 
shall be less than the maximum allowable temperature 

(b) The assembled modular hot water heating boiler 
shall also be equipped with 

(1) a safety limit control that will cut off the fuel 
supply to prevent the water temperature from exceeding 
the maximum allowable temperature at the boiler outlet. 
The control shall be constructed to prevent a temperature 
setting above the maximum. This control shall be located 
within 3 ft. (1.0 m) of the fitting connecting the last module 
to the heating supply piping. 

(2) low water fuel cutoff, see HG-614. 

HG-620 FOR ALL BOILERS 

HG-621 INSTRUMENTS, FITTINGS, AND 

CONTROLS MOUNTED INSIDE 

BOILER JACKETS 

Any or all instruments, fittings, and controls required 
by these rules may be installed inside of boiler jackets 



54 



2007 SECTION IV 



provided the water gage on a steam boiler is accessible 
without the use of tools and provided the water gage and 
pressure gage on a steam boiler or the thermometer and 
pressure gage on a water boiler are visible through an 
opening or openings at all times. 



HG-630 ELECTRIC WIRING 

HG-631 ELECTRICAL CODE COMPLIANCE 

All field wiring for controls, heat generating apparatus, 
and other appurtenances necessary for the operation of the 
boiler or boilers should be installed in accordance with the 
provisions of the National Electric Code and/or should 
comply with the applicable local electrical codes. All boil- 
ers supplied with factory mounted and wired controls, heat 
generating apparatus, and other appurtenances necessary 
for the operation of the boilers should be installed in accor- 
dance with the provisions of the nationally recognized 
standards such as listed in footnote 2 of HG-640. 



HG-632 TYPE CIRCUITRY TO BE USED 

Whether field or factory wired, the control circuitry shall 
be positively grounded and shall operate at 150 V or less. 
One of the two following systems may be employed to 
provide the control circuit. 

(a) Two-Wire Nominal 120 V System With Separate 
Equipment Ground Conductor 

(1) This system shall consist of the line, neutral, and 
equipment ground conductors. The control panel frame 
and associated control circuitry metallic enclosures shall 
be electrically continuous and be bonded to the equipment 
ground conductor. 

(2) The equipment ground conductor and the neutral 
conductor shall be bonded together at their origin in the 
electrical system as required by the NEC. 1 

(3) The line side of the control circuit shall be pro- 
vided with a time delay fuse sized as small as practicable. 

(b) Two- Wire Nominal 120 V System Obtained By Using 
an Isolation Transformer 

(1) The two- wire control circuit shall be obtained 
from the secondary side of an isolation transformer. One 
wire from the secondary of this transformer shall be electri- 
cally continuous and shall be bonded to a convenient cold 
water pipe. All metallic enclosures of control components 
shall be securely bonded to this ground control circuit wire. 
The primary side of the isolation transformer will normally 
be a two-wire source with a potential of 230 V or 208 V 
or 440 V. 

(2) Both sides of the two-wire primary circuit shall 
be fused. The hot leg on the load side of the isolation 



transformer shall be fused as small as practicable and in 
no case fused above the rating of the isolation transformer. 



HG-633 LIMIT CONTROLS 

Limit controls shall be wired on the hot or line side of 
the control circuit. 



HG-634 SHUTDOWN SWITCHES AND 
CIRCUIT BREAKERS 

A manually operated remote heating plant shutdown 
switch or circuit breaker should be located just outside 
the boiler room door and marked for easy identification. 
Consideration should also be given to the type and location 
of the switch to safeguard against tampering. If the boiler 
room door is on the building exterior the switch should be 
located just inside the door. If there is more than one door 
to the boiler room, there should be a switch located at 
each door. 

(a) For atmospheric-gas burners, and oil burners where 
a fan is on a common shaft with the oil pump, the complete 
burner and controls should be shut off. 

(b) For power burners with detached auxiliaries, only 
the fuel input supply to the firebox need be shut off. 



HG-640 CONTROLS AND HEAT 

GENERATING APPARATUS 

(a) Oil and gas-fired and electrically heated boilers 
should be equipped with suitable primary (flame safeguard) 
safety controls, safety limit switches, and burners or electric 
elements as required by a nationally recognized standard. 2 

(b) The symbol of the certifying organization 3 that has 
investigated such equipment as having complied with a 
nationally recognized standard shall be affixed to the equip- 
ment and shall be considered as evidence that the unit was 
manufactured in accordance with that standard. 



Examples of these nationally recognized standards are: 

American National Standard/CSA Standard Z21.13/CSA 4.9 for Gas- 
Fired Low Pressure Steam and Hot Water Boilers. 

American National Standard/CSA Standard Z21.17/CSA 2.7 for 
Domestic Gas Conversion Burners. 

Underwriters Laboratories, Inc., UL 296, Standards for Safety, Oil 
Burners. 

Underwriters Laboratories, Inc., UL 726, Standards for Safety, Oil 
Fired Boiler Assemblies. 

Underwriters Laboratories, Inc., UL 795, Standards for Safety, Com- 
mercial-Industrial Gas-Heating Equipment. 

Underwriters Laboratories, Inc., UL 834, Electric Heating, Water Sup- 
ply and Power Boilers. 

A certifying organization is one that provides uniform testing, exami- 
nation, and listing procedures under established, nationally recognized 
standards and that is acceptable to the authorities having jurisdiction. 



See Appendix H. 



55 



2007 SECTION IV 



ARTICLE 7 
INSTALLATION REQUIREMENTS 



HG-700 INSTALLATION REQUIREMENTS, 
ALL BOILERS 

HG-701 MOUNTING SAFETY AND SAFETY 
RELIEF VALVES 
HG-701.1 Permissible Mounting. Safety valves and 
safety relief valves shall be located in the top or side 1 of 
the boiler. They shall be connected directly to a tapped or 
flanged opening in the boiler, to a fitting connected to the 
boiler by a short nipple, to a Y-base, or to a valveless header 
connecting steam or water outlets on the same boiler. Coil 
or header type boilers shall have the safety valve or safety 
relief valve located on the steam or hot water outlet end. 
Safety valves and safety relief valves shall be installed 
with their spindles vertical. The opening or connection 
between the boiler and any safety valve or safety relief 
valve shall have at least the area of the valve inlet. 

HG-701.2 Requirements for Common Connections 
for Two or More Valves 

(a) When a boiler is fitted with two or more safety 
valves on one connection, this connection shall have a 
cross-sectional area not less than the combined areas of 
inlet connections of all the safety valves with which it 
connects. 

(b) When a Y-base is used, the inlet area shall be not 
less than the combined outlet areas. When the size of the 
boiler requires a safety valve or safety relief valve larger 
than A\ in. (115 mm) in diameter, two or more valves 
having the required combined capacity shall be used. When 
two or more valves are used on a boiler, they may be 
single, directly attached, or mounted on a Y-base. 

HG-701.3 Threaded Connections. A threaded connec- 
tion may be used for attaching a valve. 

HG-701.4 Prohibited Mountings. Safety and safety 
relief valves shall not be connected to an internal pipe in 
the boiler. 

HG-701.5 Use of Shutoff Valves Prohibited. No shut- 
off of any description shall be placed between the safety 



1 The top or side of the boiler shall mean the highest practicable part 
of the boiler proper but in no case shall the safety valve be located below 
the normal operating level and in no case shall the safety relief valve be 
located below the lowest permissible water level. 



or safety relief valve and the boiler, or on discharge pipes 
between such valves and the atmosphere. 

HG-701.6 Safety and Safety Relief Valve Discharge 
Piping 

(a) A discharge pipe shall be used. Its internal cross- 
sectional area shall be not less than the full area of the 
valve outlet or of the total of the valve outlets discharging 
thereinto and shall be as short and straight as possible and 
so arranged as to avoid undue stress on the valve or valves. 
A union may be installed in the discharge piping close to 
the valve outlet. When an elbow is placed on a safety or 
safety relief valve discharge pipe, it shall be located close 
to the valve outlet downstream of the union. 

(b) The discharge from safety or safety relief valves 
shall be so arranged that there will be no danger of scalding 
attendants. The safety or safety relief valve discharge shall 
be piped away from the boiler to the point of discharge, 
and there shall be provisions made for properly draining 
the piping. The size and arrangement of discharge piping 
shall be independent of other discharge piping and shall 
be such that any pressure that may exist or develop will 
not reduce the relieving capacity of the relieving devices 
below that required to protect the boiler. 

HG-701.7 Temperature and Pressure Safety Relief 
Valves. Hot water heating or supply boilers limited to a 
water temperature of 210°F (99°C) may have one or more 
officially rated temperature and pressure safety relief valves 
installed. The requirements of HG-701.1 through 
HG-701.6 shall be met, except as follows: 

(a) A Y-type fitting shall not be used. 

(b) If additional valves are used they shall be tempera- 
ture and pressure safety relief valves. 

(c) When the temperature and pressure safety relief 
valve is mounted directly on the boiler with no more than 
4 in. (100 mm) maximum interconnecting piping, the valve 
may be installed in the horizontal position with the outlet 
pointed down. 

HG-703 PIPING 2 

HG-703.1 Provisions for Expansion and Contrac- 
tion. Provisions shall be made for the expansion and con- 
traction of steam and hot water mains connected to boilers 



2 Guidance for the design of piping systems may be found in ASME 
B31.9, Building Services Piping. 



56 



2007 SECTION IV 



by providing substantial anchorage at suitable points and 
by providing swing joints when boilers are installed in 
batteries, so there will be no undue strain transmitted to 
the boilers. See Figs. HG-703.1(a), HG-703.1(b), and 
HG-703.2 for typical schematic arrangements of piping 
incorporating strain absorbing joints for steam and hot 
water heating boilers. 

HG-703.2 Return Pipe Connections 

(a) The return pipe connections of each boiler supplying 
a gravity return steam heating system shall be so arranged 
as to form a loop substantially as shown in 
Fig. HG-703.1(b) so that the water in each boiler cannot 
be forced out below the safe water level. 

(b) For hand-fired boilers with a normal grate line, the 
recommended pipe sizes detailed as "A" in Fig. HG-703.1 
are NPS \\ (DN 40) for 4 ft 2 (0.37 m 2 ) or less firebox 
area at the normal grate line, NPS 2 l / 2 (DN 65) for areas 
more than 4 ft 2 (0.37 m 2 ) up to 14.9 ft 2 (1.4 m 2 ), and NPS 4 
(DN 100) for 15 ft 2 (1.4 m 2 ) or more. 

(c) For automatically fired boilers that do not have a 
normal grate line, the recommended pipe sizes detailed as 
"A" in Fig. HG-703.1 are NPS \\ (DN 40) for boilers 
with minimum safety valve relieving capacity 250 lb/hr 
(113 kg/hr) or less, NPS l\ (DN 65) for boilers with 
minimum safety valve relieving capacity from 251 lb/hr 
(114 kg/hr) to 2,000 lb/hr (900 kg/hr), inclusive, and NPS 4 
(DN 100) for boilers with more than 2,000 lb/hr (900 kg/hr) 
minimum safety valve relieving capacity. 

(d) Provision shall be made for cleaning the interior of 
the return piping at or close to the boiler. Washout openings 
may be used for return pipe connections and the washout 
plug placed in a tee or a cross so that the plug is directly 
opposite and as close as possible to the opening in the 
boiler. 



HG-705 FEEDWATER AND MAKEUP WATER 
CONNECTIONS 

(a) Steam Boilers. Feedwater or water treatment shall 
be introduced into a boiler through the return piping system. 
Alternatively, feedwater or water treatment may be intro- 
duced through an independent connection. The water flow 
from the independent connection shall not discharge 
directly against parts of the boiler exposed to direct radiant 
heat from the fire. Feedwater or water treatment shall not 
be introduced through openings or connections provided 
for inspection or cleaning, safety valve, water column, 
water gage glass, or pressure gage. The feedwater pipe shall 
be provided with a check valve or a backflow preventer 
containing a check valve 3 near the boiler and a stop valve 



3 Plumbing codes may require the installation of a reduced pressure 
principle backflow preventer on a boiler when the makeup water source 
is from a potable water supply. 



or cock between the check valve and the boiler or between 
the check valve and the return pipe system. 

(b) Hot Water Boilers. Makeup water may be introduced 
into a boiler through the piping system or through an inde- 
pendent connection. The water flow from the independent 
connection shall not discharge directly against parts of the 
boiler exposed to direct radiant heat from the fire. Makeup 
water shall not be introduced through openings or connec- 
tions provided exclusively for inspection or cleaning, safety 
relief valve, pressure gage, or temperature gage. The 
makeup water pipe shall be provided with a check valve 
or a backflow preventer containing a check valve 3 near the 
boiler and a stop valve or cock between the check valve 
and the boiler or between the check valve and the piping 
system. 



HG-707 OIL HEATERS 

(a) A heater for oil or other liquid harmful to boiler 
operation shall not be installed directly in the steam or 
water space within a boiler. 

(b) Where an external type heater for such service is 
used, means shall be provided to prevent the introduction 
into the boiler of oil or other liquid harmful to boiler 
operation. 



HG-708 STORAGE TANKS FOR HOT WATER 
SUPPLY SYSTEMS 

If a system is to utilize a storage tank that exceeds the 
capacity exception of HLW-101.2(c), the tank shall be 
constructed in accordance with the rules of Part HLW; 
Section VIII, Division 1; or Section X. For tanks con- 
structed to Section X, the maximum allowable temperature 
marked on the tank shall equal or exceed the maximum 
water temperature marked on the boiler. 



HG-709 PROVISIONS FOR THERMAL 
EXPANSION IN HOT WATER 
SYSTEMS 

All hot water heating systems incorporating hot water 
tanks or fluid relief columns shall be so installed as to 
prevent freezing under normal operating conditions. 

HG-709. 1 Heating Systems With Open Expansion 
Tank. An indoor overflow from the upper portion of the 
expansion tank shall be provided in addition to an open 
vent, the indoor overflow to be carried within the building 
to a suitable plumbing fixture or the basement. 

HG-709.2 Closed Heating Systems. An expansion 
tank shall be installed that will be consistent with the 
volume and capacity of the system. If the system is 



57 



FIG. HG-703.1(a) STEAM BOILERS IN BATTERY - PUMPED RETURN - ACCEPTABLE PIPING INSTALLATION 



Steam main 




Heating 
supply 



Pump control 
and gage glass 



Blowoff 
valve/drain 



Single Return 
Shown 



GENERAL NOTES: ' From receiver tank 

(a) Return connections shown for a multiple boiler installation may not always insure that the system will operate properly. In order to 
maintain proper water levels in multiple boiler installations, it may be necessary to install supplementary controls or suitable devices. 

(b) Plumbing codes may require the installation of a reduced pressure principle backflow preventer on a boiler when the makeup water 
source is from a potable water supply. 

NOTE: 

(1) Recommended for 1 in. (DN 25) and larger safety valve discharge. 



FIG. HG-703.1(b) STEAM BOILERS IN BATTERY - GRAVITY RETURN - ACCEPTABLE PIPING INSTALLATION 



Steam main 



Heating 
supply 




Water column 
and gage glass 



Single Return 
Shown 



Heating return 

GENERAL NOTES: 

(a) Return connections shown for a multiple boiler installation may not always insure that the system will operate properly. In order to maintain 
proper water levels in multiple boiler installations, it may be necessary to install supplementary controls or suitable devices. 

(b) Plumbing codes may require the installation of a reduced pressure principle backflow preventer on a boiler when the makeup water source is 
from a potable water supply. 

NOTE: 

(1) Recommended for 1 in. (DN 25) and larger safety valve discharge. 



2007 SECTION IV 



FIG. HG-703.2 HOT WATER BOILERS IN BATTERY - ACCEPTABLE PIPING INSTALLATION 



Expansion 
tank 



rf Heating 
External low water ' supply 

High limit fuel cutoff (1) r*\/' 

COntro1 / JO*— P referred location of 

St0P \ y°J )S circulating pump 

valve yiA^jprl -r 

Temperature 



High limit 
control 




Temperature 
pressure gage 



Make up 
water 



Safety relief valve, 
discharge piping I S\ 
(with union) , \y 



Alternate make up 
water arrangement 




Internal 
low-water 
fuel cut off 
(alternate 
arrangement) 



Maximum 
temperature 
imit control 



Heating 
return 



Pressure 
reducing 
valve 



Drain valve 



Alternate expansion 
■ — - tank with diaphragm 
(required on each 
boiler) 



GENERAL NOTE: Plumbing codes may require the installation of a reduced pressure principle backflow preventer on a boiler when the makeup 
water source is from a potable water supply. 

NOTES: 

(1) Recommended control. See HG-614. Acceptable shutoff valves or cocks in the connecting piping may be installed for convenience of control 
testing and/or service. 

(2) The common return header stop valves may be located on either side of the check valves. 



designed for a working pressure of 30 psi (200 kPa) or 
less, the tank shall be suitably designed for a minimum 
hydrostatic test pressure of 75 psi (520 kPa). Expansion 
tanks for systems designed to operate above 30 psi 
(200 kPa) shall be constructed in accordance with Section 
VIII, Division 1. Alternatively, a tank built to Section X 
requirements may be used if the pressure and temperature 
ratings of the tank are equal to or greater than the pressure 
and temperature ratings of the system. Provisions shall be 
made for draining the tank without emptying the system, 
except for prepressurized tanks. 



The minimum capacity of the closed type expansion 
tank may be determined from Table HG-709.2 or from 
the following formula where the necessary information is 
available: 

(U.S. Customary Units) 

V t = [(0.000417- - 0.0466) V, ]l[(PJP f ) - (P a /P )] 
(SI Units) 

V, = [(0.181557- - 8.236) V 5 ]/[(PJP f ) - (P JP )) 
where 



60 



2007 SECTION IV 



TABLE HG-709.2 

EXPANSION TANK CAPACITIES 

FOR FORCED HOT WATER SYSTEMS 

[Based on average operating water 

temperature 195°F (90°C), fill pressure 12 psig (83 kPa), 

and maximum operating pressure 30 psig (200 kPa)] 





Tank Capacities, 


gal (m 3 ) 


System Volume, 


Prepressurized 


Nonpressurized 


gal (m 3 ) 


Diaphragm Type 


Type 


100 (0.38) 


9 (0.034) 


15 (0.057) 


200 (0.76) 


17 (0.064) 


30 (0.114) 


300 (1.14) 


25 (0.095) 


45 (0.170) 


400 (1.51) 


33 (0.125) 


60 (0.227) 


500 (1.89) 


42 (0.159) 


75 (0.284) 


1,000 (3.79) 


83 (0.314) 


150(0.568) 


2,000 (7.57) 


165(0.625) 


300(1.136) 



GENERAL NOTE: System volume includes volume of water in boiler, 
radiation, and piping, not including the expansion tank. Expansion tank 
capacities are based on an acceptance factor of 0.4027 for prepressur- 
ized types and 0.222 for nonprepressurized types. A procedure for 
estimating system volume and determining expansion tank sizes for 
other design conditions may be found in Chapter 12 of the 1996 HVAC 
Systems and Equipment Volume of the ASHRAE Handbook. 



P a = atmospheric pressure 

Pf = fill pressure 

P = maximum operating pressure 

T = average operating temperature 

V s = volume of system, not including tanks 

V t = minimum volume of tanks 

HG-709.3 Hot Water Supply Systems. If a system is 
equipped with a check valve or pressure reducing valve in 
the cold water inlet line, consideration should be given to 
the installation of an airtight expansion tank or other suit- 
able air cushion. Otherwise, due to the thermal expansion 
of the water, the safety relief valve may lift periodically. 
If an expansion tank is provided, it shall be constructed in 
accordance with Section VIII, Division 1 or Section X. 
Except for prepressurized tanks, which should be installed 
on the cold water side, provisions shall be made for draining 
the tank without emptying the system. See Fig. HLW-809. 1 
for a typical acceptable installation. 



HG-710 STOP VALVES 

HG-710.1 For Single Steam Boilers. When a stop 
valve is used in the supply pipe connection of a single 
steam boiler, there shall be one used in the return pipe 
connection. 

HG-710.2 For Single Hot Water Heating Boilers 

(a) Stop valves shall be located at an accessible point 
in the supply and return pipe connections as near the boiler 
nozzle as is convenient and practicable, of a single hot 



water heating boiler installation to permit draining the 
boiler without emptying the system. 

(b) When the boiler is located above the system and 
can be drained without draining the system, stop valves 
may be eliminated. 

HG-710.3 For Multiple Boiler Installations. A stop 
valve shall be used in each supply and return pipe connec- 
tion of two or more boilers connected to a common system. 
See Figs. HG-703.1 and HG-703.2. 

HG-710.4 Type of Stop Valve(s) 

(a) All valves or cocks shall conform with the applicable 
portions of HF-203 and may be ferrous or nonferrous. 

(b) The minimum pressure rating of all valves or cocks 
shall be at least equal to the pressure stamped upon the 
boiler, and the temperature rating of such valves or cocks, 
including all internal components, shall be not less than 
250°F (120°C). 

(c) Valves or cocks shall be flanged, threaded, or have 
ends suitable for welding or brazing. 

(d) All valves or cocks with stems or spindles shall have 
adjustable pressure type packing glands and, in addition, 
all plug type cocks shall be equipped with a guard or gland. 
The plug or other operating mechanism shall be distinctly 
marked in line with the passage to indicate whether it is 
opened or closed. 

(e) All valves or cocks shall have tight closure when 
under boiler hydrostatic test pressure. 

HG-710.5 Identification of Stop Valves by Tags. 

When stop valves are used, they shall be properly desig- 
nated substantially as follows by tags of metal or other 
durable material fastened to them: 

Supply Valve - Number ( ) 

Do Not Close Without Also 

Closing Return Valve - 

Number ( ) 

Return Valve - Number ( ) 

Do Not Close Without Also 

Closing Supply Valve - 

Number ( ) 



HG-715 BOTTOM BLOWOFF AND 
DRAIN VALVES 

(a) Bottom Blowoff Valve. Each steam boiler shall have 
a bottom blowoff connection fitted with a valve or cock 
connected to the lowest water space practicable with a 
minimum size as shown in Table HG-715. The discharge 
piping shall be full size to the point of discharge. 



61 



2007 SECTION IV 



TABLE HG-715 

SIZE OF BOTTOM BLOWOFF PIPING, 

VALVES, AND COCKS 



Minimum Required Safety Valve 


Blowoff Piping, 


Capacity, lb (kg) of steam/hr 


Valves, and Cocks 


[Note (1)] 


Min. Size NPS (DN) 


Up to 500 (225) 


% (20) 


501 to 1,250 (225 to 550) 


1 (25) 


1,251 to 2,500 (550 to 1 200) 


lV 4 (32) 


2,501 to 6,000 (1 200 to 2 700) 


lV 2 (40) 


6,001 (2 700) and larger 


2 (50) 



NOTE: 

(1) To determine the discharge capacity of safety relief valves in terms 
of Btu, the relieving capacity in lb of steam/hr is multiplied by 1,000. 



(1) The individual modules shall be manifolded 
together at the job-site without any intervening valves. The 
header or manifold piping is field piping and is exempt 
from Article 2, Part HG, HF, HB, or HC. 

(2) The assembled modular steam heating boiler shall 
also be equipped with 

(a) feedwater connection, see HG-705(a) 

(b) return pipe connection, see HG-703.2 

(3) The assembled modular hot water heating boiler 
shall also be equipped with 

(a) makeup water connection, see HG-705(b) 

(b) provision for thermal expansion, see HG-709 

(c) stop valves, see HG-710.2 



(b) Boilers having a capacity of 25 gal (95 1) or less 
are exempt from the above requirements, except that they 
must have an NPS % (DN 20) minimum drain valve. 
07 (c) Drain Valve. Each steam or hot water boiler shall 

have one or more drain connections, fitted with valves or 
cocks. These shall be connected at the lowest practicable 
point on the boiler, or to the lowest point on piping con- 
nected to the boiler, at the lowest practicable point on the 
boiler. The minimum size of the drain piping, valves, and 
cocks shall be NPS % (DN 20). The discharge piping shall 
be full size to the point of discharge. When the blowoff 
connection is located at the lowest water containing space, 
a separate drain connection is not required. 

(d) Minimum Pressure Rating. The minimum pressure 
rating of valves and cocks used for blowoff or drain pur- 
poses shall be at least equal to the pressure stamped on 
the boiler but in no case less than 30 psi (200 kPa). The 
temperature rating of such valves and cocks shall not be 
less than 250°F (120°C). 



HG-716 MODULAR BOILERS 

(a) Individual Modules 

(1) The individual modules shall comply with all the 
requirements of Part HG, except as specified in HG-607, 
HG-615, and this paragraph. The individual modules shall 
be limited to a maximum input of 400,000 Btuh (gas), 
3 gal/hr (11 1/hr) (oil), or 115 kW (electricity). 

(2) Each module of a steam heating boiler shall be 
equipped with 

(a) safety valve, see HG-701 

(b) blowoff valve, see HG-715(a) 

(c) drain valve, see HG-7 15(c) 

(3) Each module of a modular hot water heating 
boiler shall be equipped with 

(a) safety relief valve, see HG-701 

(b) drain valve, see HG-7 15(c) 

(b) Assembled Modular Boilers 



HG-720 SETTING 

Boilers of wrought materials of the wet-bottom type 
having an external width of over 36 in. (900 mm) shall 
have not less than 12 in. (300 mm) between the bottom of 
the boiler and the floorline, with access for inspection. 
When the width is 36 in. (900 mm) or less, the distance 
between the bottom of the boiler and the floorline shall be 
not less than 6 in. (150 mm), except that, when any part 
of the wet bottom is not farther from an outer edge than 
12 in. (300 mm), this distance shall be not less than 4 in. 
(100 mm). 



HG-725 METHODS OF SUPPORT 
HG-725.1 Loadings 

(a) The design and attachment of lugs, hangers, saddles, 
and other supports shall take into account the stresses due to 
hydrostatic head in determining the minimum thicknesses 
required. Additional stresses imposed by effects other than 
working pressure or static head, which increase the average 
stress by more than 10% of the allowable working stress, 
shall also be taken into account. These effects include the 
weight of the component and its contents, and the method 
of support. 

(b) In applying the requirements of (a) above, localized 
stresses due to concentrated support loads, temperature 
changes, and restraint against dilation of the boiler due to 
pressure shall be provided for. Lugs, hangers, brackets, 
saddles, and pads shall conform satisfactorily to the shape 
of the shell or surface to which they are attached or are in 
contact. 

HG-725.2 Boilers Over 72 in. (1 800 mm) in Diame- 
ter. A horizontal-return tubular boiler over 72 in. 
(1 800 mm) in diameter shall be supported from steel hang- 
ers by the outside-suspension type of setting, independent 
of the furnace wall. The hangers shall be so designed that 
the load is properly distributed. 



62 



2007 SECTION IV 



HG-725.3 Boilers Over 54 in. (1 400 mm) up to 72 in. 
(1 800 mm) in Diameter. A horizontal-return tubular 
boiler over 54 in. (1 400 mm) and up to and including 
72 in. (1 800 mm) in diameter shall be supported by the 
outside-suspension type of setting, or at four points by not 
less than eight steel brackets set in pairs, the brackets of 
each pair to be spaced not over 2 in. (50 mm) apart and the 
load to be equalized between them. [See Fig. HG-725(a).] 

HG-725.4 Boilers up to 54 in. (1 400 mm) in Diame- 
ter. A horizontal-return tubular boiler up to and including 
54 in. (1 400 mm) in diameter shall be supported by the 
outside-suspension type of setting, or by not less than two 
steel brackets on each side. 

HG-725.5 Supporting Members. If the boiler is sup- 
ported by structural steel work, the steel supporting mem- 
bers shall be so located or insulated that the heat from the 
furnace can not impair their strength. 

HG-725.6 Lugs or Hangers. Lugs, hangers, or brackets 
made of materials in accordance with the Code require- 
ments may be attached by fusion welding provided they 
are attached by fillet welds along the entire periphery or 
contact edges. Figure HG-725(b) illustrates an acceptable 
design of hanger bracket with the additional requirement 
that the center pin be located at the vertical center line 



over the center of the welded contact surface. The bracket 
plates shall be spaced at least 2 ! / 2 in- (64 mm) apart, but 
this dimension shall be increased if necessary to permit 
access for the welding operation. The stresses computed 
by dividing the total load on each lug, hanger, or bracket, 
by the minimum cross-sectional area of the weld shall not 
exceed 2800 psi (19 MPa). Where it is impractical to attach 
lugs, hangers, or brackets by welding, studs with not less 
than 10 threads/in. (approx. 4 threads/cm) may be used. 
In computing the shearing stresses, the root area at the 
bottom of the thread shall be used. The shearing and crush- 
ing stresses on studs shall not exceed 8% of the strength 
given in Table HF-300. 1 for bolting materials. 

HG-725.7 Settings. Boilers of wrought materials of the 
wet-bottom type having an external width of over 36 in. 
(900 mm) shall be supported so as to have a minimum 
clearance of 12 in. (300 mm), between the bottom of the 
boiler and the floor, to facilitate inspection. When the width 
is 36 in. (900 mm) or less, the clearance between the 
bottom of the boiler and the floorline shall be not less than 
6 in. (150 mm), except when any part of the wet bottom 
is not farther from the outer edge than 12 in. (300 mm). 
This clearance shall be not less than 4 in. (100 mm). Boiler 
insulation, saddles, or other supports shall be arranged so 
that inspection openings are readily accessible. 



63 



2007 SECTION IV 



FIG. HG-725(a) SPACING AND WELD DETAILS FOR SUPPORTING LUGS IN PAIRS ON HORIZONTAL-RETURN 

TUBULAR BOILER 

T- not less than 
1% of the boiler 
diameter 

2 in. 

4 v (51 mm; 4 ^ 






0.7 T 




FIG. HG-725(b) WELDED BRACKET CONNECTION FOR HORIZONTAL-RETURN TUBULAR BOILER 

B 



2V 2 in. (64 mm) min 



R- not less than 
1 1 / 2 x diameter 
of hole 

7= not less than 
1% of the boiler 
diameter 




64 



2007 SECTION IV 



PART HF 
REQUIREMENTS FOR BOILERS 
CONSTRUCTED OF WROUGHT 

MATERIALS 



ARTICLE 1 
GENERAL 



HF-100 SCOPE 

The rules in Part HF are applicable to heating boilers that are constructed primarily of wrought materials, and shall 
be used in conjunction with general requirements of Part HG of this Section. 



65 



2007 SECTION IV 



ARTICLE 2 
MATERIAL REQUIREMENTS 



HF-200 GENERAL MATERIAL 
REQUIREMENTS 

Materials other than those described herein may not be 
used, unless approved by the Boiler and Pressure Vessel 
Committee in accordance with Appendix 5 in Section n, 
PartD. 



HF-201 



PLATE 



(a) Plate used in the construction of pressure containing 
parts shall conform to one of the specifications given in 
Section II for which allowable stress values are given in 
Tables HF-300.1 and HF-300.2 except as otherwise pro- 
vided in HF-203 and HF-205. 

(b) Stainless plates of SA-240 for which allowable 
stress values are given in Table HF-300. 1 may be used in 
the construction of hot water heating boilers provided the 
following are met: 

(1) The water temperature shall not exceed 210°F 
(99°C). 

(2) The material shall be fully annealed. 

(c) For pressure retaining plate material, a material test 
report is required to verify that the chemical and mechanical 
properties are within the permissible range listed in Sec- 
tion n. 



HF-202 RODS, BARS, AND SHAPES 

Rods, bars, and shapes may be used in boiler construc- 
tion for pressure parts such as flange rings, stiffening rings, 
braces, frames for reinforced openings, stays and staybolts, 
and similar parts. Rods, bars, and shapes used for pressure 
parts shall conform to one of the specifications in Section 
II and shall be limited to those listed in Tables HF-300. 1 
and HF-300.2, except as otherwise provided in HF-203 
and HF-205. 



HF-203 PREFABRICATED OR PREFORMED 
PRESSURE PARTS 

Prefabricated or preformed pressure parts for boilers that 
are subject to allowable working stresses due to internal 



or external pressure in the boilers and that are furnished 
by other than the shop of the manufacturer responsible 
for the completed boilers shall conform to all applicable 
requirements of the Code as related to a completed boiler, 
including inspection in the shop of the parts manufacturer 
and the furnishing of Partial Data Reports except as permit- 
ted in HF-203. 1, HF-203.2, and HF-203.3. 

HF-203.1 Cast, Forged, Rolled, or Die Formed Stan- 
dard Pressure Parts 

(a) Pressure parts such as pipe fittings, valves, flanges, 
nozzles, welding necks, welding caps, manhole frames and 
covers, and casings of pumps that are part of a boiler 
circulating system that are wholly formed by casting, forg- 
ing, or die forming shall not require inspection, mill test 
reports or Partial Data Reports; however, they shall be 
made of materials permitted under Section II or in a Code- 
accepted standard (such as ANSI) covering the particular 
type of pressure part. Such parts shall be marked with the 
name or trademark of the manufacturer and such other 
markings as are required by the several standards. Such 
markings shall be considered as the manufacturer's certifi- 
cation that the product complies with the material specifi- 
cations and standards indicated and is suitable for service 
at the rating indicated. The intent of the paragraph will 
have been met if, in lieu of the detailed marking on the 
part itself, the parts described herein have been marked in 
any permanent or temporary manner that will serve to 
identify the part with the manufacturer's written listing 
of the particular items and such listings are available for 
examination by the Inspector. 

(b) Parts of small size falling within this category for 
which it is difficult or impossible to obtain identified mate- 
rial or that may be stocked and for which mill test reports 
or certificates cannot be economically obtained and are not 
customarily furnished, and that do not appreciably affect 
the safety of the vessel, may be used for relatively unim- 
portant parts or parts stressed to not more than 50% of the 
stress value permitted by the Code provided they are suit- 
able for the purpose intended and are accepted by the 
Inspector [see HF-203. 1(a)]. The manufacturer of the com- 
pleted vessel shall satisfy himself that the part is suitable 
for the design conditions specified for the completed vessel. 



66 



2007 SECTION IV 



HF-203.2 Cast, Forged, Rolled, or Die Formed Non- 
standard Pressure Parts. Pressure parts such as shells, 
heads, removable cover plates, and pipe coils that are 
attached to other wrought parts and that are wholly formed 
by casting, forging, rolling, or die forming may be supplied 
basically as materials. All such parts shall be made of 
materials permitted under Section II and the manufacturer 
of the part shall furnish mill test reports or other acceptable 
evidence to that effect. Such parts shall be marked with 
the name or trademark of the manufacturer and with such 
other markings as will serve to identify the particular parts 
with accompanying material identification. The manufac- 
turer of the completed boiler shall satisfy himself that the 
part is suitable for the design conditions specified for the 
completed boiler. 

HF-203.3 Welded Standard Pressure Parts for Use 
Other Than the Shell of a Boiler 1 

(a) Pressure parts such as pipe fittings, nozzles, welding 
necks, welding caps, valves, and flanges that are fabricated 
by one of the welding processes recognized by the Code 
shall not require inspection, mill test reports, or Partial 
Data Reports provided 

(1) all such parts are made of materials permitted 
under Section n or in a Code-accepted standard 

(2) if arc or gas welded, the welding complies with 
the rules of this Section 

(b) Such parts shall be marked with the name or trade- 
mark of the manufacturer and with such other markings 
as will serve to identify the materials of which the parts 
are made. Such markings shall be considered as the manu- 
facturer' s certification that the product complies with 
HF-203.3(a)(l). A statement by the parts manufacturer 
that all welding complies with Code requirements shall 
be accepted as evidence that the product complies with 
HF-203.3(a)(2). 



HF-204 



PIPE AND TUBES 



Pipe and tubes of seamless or welded construction shall 
conform to one of the specifications given in Section II 
for which allowable stress values are given in 
Tables HF-300.1 and HF-300.2 except as otherwise pro- 
vided in HF-203 and HF-205 when used in the construction 
of pressure containing parts. 

HF-204.1 Integrally Finned Tubes. Integrally finned 
tubes may be made from tubes that conform in every 
respect with one of the specifications given in Section n, 
except that the pressure test is not required for nonferrous 
tubes. These tubes may be used under the following condi- 
tions. 



(a) The tubes after finning shall have a temper or condi- 
tion that conforms to one of those provided in the governing 
specifications. 

(b) The maximum allowable stress value for the finned 
tube shall be that given in Tables HF-300.1 and HF-300.2 
for the tube before finning, except as permitted in (c) below. 

(c) The maximum allowable stress value for a temper 
or condition that has a higher stress value than that of the 
tube before finning may be used provided that qualifying 
tensile tests demonstrate that such a temper or condition 
is obtained. The stress values used shall not exceed those 
shown in Tables HF-300.1 and HF-300.2 for the temper 
or condition involved. The qualifying tensile tests shall be 
made on specimens of finned tube from which the fins 
have been removed by machining. 

(d) The maximum allowable internal or external design 
pressure of the tube shall be based on either the minimum 
wall thickness of the finned section or of the unfinned 
section, whichever is smaller. 

(e) In addition to the tests required by the governing 
specifications (except for pressure tests for nonferrous 
tubes), each tube after finning shall withstand without evi- 
dence of leakage an internal pneumatic test of not less than 
250 psi (1 720 kPa) for 5 sec. The test method used shall 
permit easy visual detection of any leakage, such as immer- 
sion of the tube under water or a pressure differential 
method. 2 A test meeting the requirements of HG-5 10(c) 
may be substituted for this requirement if the boiler design 
so permits. 

HF-204.2 Electric Resistance Welded Fin Tubes. 

Tubes with electric resistance welded fins that serve as 
extended heating surface and have no load-carrying func- 
tion may be supplied as materials. A Code Certificate 
holder need not perform the welds attaching the fins. When 
the welding process attaching the fins is automatic, welding 
procedure and performance qualification testing is not 
required. 

HF-204.3 Stainless Tubes. Stainless steel tubes, for 
which allowable stress values are given in Table HF-300. 1 , 
may be used in the construction of hot water heating or 
hot water supply boilers, provided the following conditions 
are met. 

(a) Minimum tube thickness shall be 0.035 in. 
(0.89 mm). 

(b) The required wall thickness of stainless tubes under 
internal pressure shall be determined in accordance with 
the rules for Cylindrical Parts Under Internal Pressure in 
HG-301. 

(c) The wall thickness of stainless tubes subject to exter- 
nal pressure shall be determined by using the procedures 
outlined in HG-312.3. 



1 Arc and gas welded pipe for use as the shell of a boiler shall be 
subject to the same requirements as a shell fabricated from plate, including 
inspection at the point of manufacture and Partial Data Reports. 



The pressure differential method is described in Materials and 
Research Standards, Vol. 1, No. 7, July 1961, published by ASTM. 



67 



2007 SECTION IV 



(d) Tubes installed by rolling shall have an additional 
0.04 in. (1.02 mm) wall thickness added to the minimum 
required thickness. 

(e) For austenitic stainless steel materials only, the water 
temperature shall not exceed 210°F (99°C). [See 
Table HF-300.1, Note (16).] 

(f) Welding or brazing shall be qualified in accordance 
with Section IX. 



HF-205 



MATERIAL NOT FULLY IDENTIFIED 



Material that has lost its identity with a permitted speci- 
fication may be accepted provided that it satisfies the condi- 
tions given in either HF-205. 1 or HF-205.2. 

HF-205.1 Acceptance by Authentic Test Record and 
Marking. Each piece shall be shown to have chemical 
requirements and mechanical properties within the permis- 
sible range of the permitted specification in Section II by 
an authentic test record and by marking identifying it with 
that record. When the permitted specification requires other 
tests or more restrictive tests than those of the specification 
covered by the authentic test record, the material shall be 
subjected to sufficient additional tests to satisfy the Inspec- 
tor that it complies with the permitted specification. 

HF-205.2 Acceptance by Testing 

(a) Plate. The chemical check analyses and mechanical 
tests of plates shall be made as required in the permitted 
specification with the following modifications. The carbon 
and manganese contents shall be determined in all check 
analyses. The Inspector shall decide whether these contents 
are acceptable when the permitted specification does not 
specify carbon and manganese limits. When the direction 
of rolling is not definitely known, two tension specimens 
shall be taken at right angles to each other from a corner 
of each plate, and two bend specimens shall be taken from 
the middle of adjacent sides of each plate. One tension 
specimen and both bend specimens shall meet the permitted 
specification requirements. 

(b) Tubes and Pipe. Each length of tube or pipe shall 
be subjected to a chemical check analysis and sufficient 
mechanical tests to satisfy the Inspector that all the material 
is identified with a given heat or heat treatment lot and that 
the material complies with the chemical and mechanical 
requirements of the permitted specification. Material speci- 
fied as suitable for welding, cold bending, close coiling, 
and similar operations shall be given sufficient check tests 
to satisfy the Inspector that it is suitable for the fabrication 
procedure to be used. 



(c) Rods, Bars, and Shapes. Each length of rods shall 
be subjected to a chemical check analysis and sufficient 
mechanical tests to satisfy the Inspector that all the material 
is identified with a given heat or heat treatment lot, and that 
the material complies with the chemical and mechanical 
requirements of the permitted specification. Material speci- 
fied as suitable for welding, cold bending, and similar 
operations shall be given check tests to satisfy the Inspector 
that it is suitable for the fabrication procedure to be used. 

HF-205.3 Marking and Report on Tests of Noniden- 
tiiied Material. When the identity of the material with the 
permitted specification has been established in accordance 
with HF-205.1 or HF-205.2, each piece of material (except 
as alternatively provided in the specification for tubes, pipe, 
rods, bars, or shapes) shall be marked to the satisfaction 
of the Inspector by the boiler manufacturer or the testing 
agency, with a marking giving the permitted specification 
number and grade or type and a serial S-number identifying 
the particular lot of material. A suitable report, clearly 
marked as being a "Report on Tests of Nonidentified Mate- 
rial," shall be furnished, properly filled out and certified 
by the boiler manufacturer or testing agency, and this 
report, when accepted by the Inspector, shall constitute 
authority to use the material. 



HF-206 RECERTIFICATION OF MATERIAL 
PRODUCED TO A SPECULATION 
NOT PERMITTED BY THIS SECTION 

A particular production lot of material may be recertified 
to a permitted specification by the boiler or part manufac- 
turer under the following conditions. 

(a) The specification to which the material was pro- 
duced, processed, and purchased must be available for 
comparison to the permitted specification. 

(b) A test report from the material manufacturer must 
be available. 

(c) The material must have marking, acceptable to the 
Inspector, for identification to the test report. 

(d) The test report must show that all chemical and 
mechanical properties of the lot comply with the require- 
ments of the permitted specification. 

( e) When conformance of the lot to the permitted speci- 
fication has been established, it may be accepted and 
marked, as required by the permitted specification, by the 
boiler or part manufacturer. 



HF-207 



AUSTENITIC STAINLESS STEEL 



Austenitic alloys are subject to stress corrosion cracking, 
intergranular attack, pitting, and crevice corrosion. Factors 
that affect the susceptibility of these materials are applied 
or residual stress, water chemistry and deposition of solids, 



68 



2007 SECTION IV 



and material condition. Susceptibility to attack is enhanced 
when the material is used in a sensitized condition or with 
residual cold work. Concentration of corrosive agents (e.g., 
chlorides, caustic or reduced sulfur species) can occur 
under deposits formed on the surface of these materials 
and can result in severe under deposit wasting or cracking. 
The following preventive measures should be considered 
in designs utilizing these materials, along with Appendix 
6, paragraph 6-300 of Section II-D: 

(a) Careful selection of materials for the specific appli- 
cation. For welded applications, low carbon grades or tita- 
nium-stabilized grades should be considered. 

(b) Proper consideration of fabrication methods and 
techniques to reduce residual stresses and sites for crevice 
corrosion. Cold working, grinding, bending, and high-heat 
input welding should be minimized. In the design of the 
boiler, stagnant fluid regions should be avoided, as should 
crevices. Weld joints should be designed to avoid integral 
back-up rings or back-up bars that are left in place and 
create a crevice. 



(c) Control of boiler water chemistry and avoidance of 
other environmental sources of chlorides, such as chloride 
containing insulation or swimming pool environments. 



HF-210 MAINTAINING MATERIAL 
IDENTIFICATION 

(a) Material for pressure parts shall carry identification 
markings as required by the applicable material specifica- 
tion. If the original identification markings are cut out or 
the material is divided into two or more parts, the marking 
shall either be accurately transferred prior to cutting or a 
coded method of identification shall be used to assure 
identification of each piece of material during subsequent 
fabrication. 

(b) Materials may be identified by any method suitable 
to the Inspector, provided the method used does not result 
in sharp discontinuities and identifies the material until the 
boiler is completed. 



69 



2007 SECTION IV 



ARTICLE 3 

DESIGN STRESSES AND MINIMUM 

THICKNESSES 



HF-300 MAXIMUM ALLOWABLE STRESS 
VALUES 

Tables HF-300. 1 and HF-300.2 give the maximum 
allowable stress values indicated for ferrous and nonferrous 
materials, respectively, conforming to the specifications 
listed therein. 



HF-301 MINIMUM THICKNESSES 1 
07 HF-301.1 Ferrous Plates 

(a) Except as permitted in (c) and (d) below and for 
cylindrical shells in Table HF-301.1, the minimum thick- 
ness of any ferrous plate, or pipe used in lieu of plate, 
under any pressure shall be % in. (6 mm). 

(b) The minimum thicknesses of ferrous shell and other 
ferrous plates, heads, and tubesheets for various shell diam- 
eters of boilers shall be as shown in Table HF-301.1. All 
sheets, except those having tubes installed by rolling, may 
be classified as shell plates. 

(c) Carbon steel plate with a thickness less than that 
permitted by HF-301. 1(a), HF-301. 1(b), and HG-312.1(a) 
may be used when all of the following requirements are 
met: 

(1) The operating service shall be limited to closed 
hot water heating systems at a maximum pressure of 30 psi 
(200 kPa). 

(2) The pressure parts shall be limited to a maximum 
diameter of 30 in. (750 mm) O.D. 

(3) No plate shall be less than 3 / 32 in. (2.5 mm) (actual 
thickness), but if less than 3 / 16 in. (5.0 mm) (actual thick- 
ness), the plate shall not be exposed to the primary products 
of combustion. 

(d) Alloy steel plate of Specification SA-240 type 
316Ti, 316L, 439 (UNS S43035), and UNS S43932, with 
a thickness less than that permitted by HF-301. 1(a), 
HF-301. 1(b), and HG-312.1(a), may be used when all of 
the following requirements are met: 



1 These minimum thicknesses for pressure shall not be less than required 
by design formulas in Part HG, Article 3, nor less than those thicknesses 
established by proof testing in Part HG, Article 5. 



(1) The operating service shall be limited to closed 
hot water heating systems at a maximum pressure of 80 psi 
(550 kPa). 

(2) The cylindrical parts for combustion chamber and 
pressure vessel shall be limited to a maximum of 38 in. 
(950 mm) outside diameter. 

( 3) The material thickness shall not be less than % 2 i n - 
(2.5 mm) (actual thickness) for combustion chamber 
design. 

(4) The material thickness shall not be less than 
0.0394 in. (1 mm) (actual thickness) for secondary flue 
gas heat exchange surfaces. 

HF-301.2 Nonferrous Plates 

(a) The minimum thickness of any nonferrous plate 
under pressure shall be % in. (3 mm) for copper, admiralty, 
and red brass, and V32 in. (2.5 mm) for copper-nickel. 

(b) The minimum thicknesses of nonferrous shells and 
other copper or copper-alloy plates, heads, and tubesheets 
for various shell diameters of boilers shall be as shown in 
Table HF-301.2. All sheets, except those having tubes 
installed by rolling, may be classified as shell plates. 

(c) The minimum thickness of any nonferrous tubesheet 
with tubes installed by rolling shall be 5 / 16 in. (8 mm). 



HF-302 BASIS FOR ESTABLISHING STRESS 
VALUES IN TABLES HF-300.1 AND 
HF-300.2 

(a) In the determination of allowable stress values for 
pressure parts, the Committee is guided by successful expe- 
rience in service, insofar as evidence of satisfactory per- 
formance is available. Such evidence is considered 
equivalent to test data where operating conditions are 
known with reasonable certainty. In the evaluation of new 
materials, it is necessary to be guided to a certain extent 
by the comparison of test information with similar data on 
successful applications of similar materials. 



70 



2007 SECTION IV 



(b) At any temperature below the creep range, the allow- 
able stresses are established at no higher than the lowest 
of the following: 

(1 ) V 5 of the specified minimum tensile strength at 
room temperature 

(2) % of the tensile strength at temperature 

(3) 2 /3 of the specified minimum yield strength at 
room temperature 

(4) 2 / 3 of the yield strength at temperature 

(c) For bolting materials, the basis for setting stresses 
is the same as for all other materials with the exception 
that (1) and (2) above are 



(1 ) % of the specified minimum tensile strength at 
room temperature, and 

(2) V4 of the tensile strength at temperature 

The following limitation also applies to bolting materi- 
als: at temperatures below the creep range, the stresses 
for materials whose strength has been enhanced by heat 
treatment or by strain hardening shall not exceed the lesser 
of 20% of the specified minimum tensile strength at room 
temperature or 25% of the specified minimum yield 
strength at room temperature unless these values are lower 
than the annealed values, in which case the annealed values 
shall be used. 



71 



2007 SECTION IV 



TABLE HF-300.1 

MAXIMUM ALLOWABLE STRESS VALUES FOR FERROUS MATERIALS, ksi (MPa) 

(Multiply by 1,000 to Obtain psi) 















Spec. Min. 


Spec. Min. 
















External 


Tensile 


Yield 




Max. Allow. 


Spec. 




Nominal 




Group 


Pressure 


Strength, 


Strength, 




Stress Value, 


No. 


Grade 


Composition 


P-No. 


No. 


Chart 


ksi (MPa) 


ksi (MPa) 


Note(s) 


ksi (MPa) 



Plate Steels 
Carbon Steels 



SA-36 




Carbon steel 


SA-285 


A 


Carbon steel 


SA-285 


B 


Carbon steel 


SA-285 


C 


Carbon steel 


SA-455 




Carbon steel 


SA-455 




Carbon steel 


SA-455 




Carbon steel 


SA-515 


60 


Carbon steel 


SA-515 


65 


Carbon steel 


SA-515 


70 


Carbon steel 


SA-516 


55 


Carbon steel 


SA-516 


60 


Carbon steel 


SA-516 


65 


Carbon steel 


SA-516 


70 


Carbon steel 


Sheet Steels 






Carbon Steels 




SA-414 


A 


Carbon steel 


SA-414 


B 


Carbon steel 


SA-414 


C 


Carbon steel 


SA-414 


D 


Carbon steel 


SA-414 


E 


Carbon steel 


SA-414 


F 


Carbon steel 


SA-414 


G 


Carbon steel 



CS-2 58.0 (400) 36.0 (250) 



1 
1 
1 


1 
1 
1 


CS-1 
CS-1 
CS-2 


45.0 (310) 
50.0 (345) 
55.0 (380) 


24.0 (165) 
27.0 (185) 
30.0 (205) 


1 
1 
1 


2 
2 
2 


CS-2 
CS-2 
CS-2 


75.0 (515) 
73.0 (505) 
70.0 (485) 


38.0 (260) 
37.0 (255) 
35.0 (240) 


1 
1 
1 


1 
1 
2 


CS-2 
CS-2 
CS-2 


60.0 (415) 
65.0 (450) 
70.0 (485) 


32.0 (220) 
35.0 (240) 
38.0 (260) 


1 
1 
1 
1 


1 
1 
1 
2 


CS-2 
CS-2 
CS-2 
CS-2 


55.0 (380) 
60.0 (415) 
65.0 (450) 
70.0 (485) 


30.0 (205) 
32.0 (220) 
35.0 (240) 
38.0 (260) 



1 1 


CS-1 


45.0 (310) 


25.0 (170) 


1 1 


CS-2 


50.0 (345) 


30.0 (205) 


1 1 


CS-2 


55.0 (380) 


33.0 (230) 


1 1 


CS-2 


60.0 (415) 


35.0 (240) 


1 1 


CS-2 


65.0 (450) 


38.0 (260) 


1 2 


CS-3 


70.0 (485) 


42.0 (290) 


1 2 


CS-3 


75.0 (515) 


45.0 (310) 



1)(2) 


11.6 (80.0) 




9.0 (62.1) 




10.0 (68.9) 




11.0 (75.8) 


(3) 


15.0 (103.0) 


(4) 


14.6 (101.0) 


(5) 


14.0 (96.5) 




12.0 (82.7) 




13.0 (89.6) 




14.0 (96.5) 




11.0 (75.8) 




12.0 (82.7) 




13.0 (89.6) 




14.0 (96.5) 



9.0 (62.1) 
10.0 (68.9) 
11.0 (75.8) 
12.0 (82.7) 
13.0 (89.6) 
14.0 (96.5) 
15.0 (103.0) 



Pipe and Tubes 
Seamless Carbon Steel 



SA-53 
SA-53 

SA-106 
SA-106 
SA-106 

SA-192 

SA-210 



A-l 



Carbon steel 
Carbon steel 

Carbon steel 
Carbon steel 
Carbon steel 

Carbon steel 

Carbon steel 



1 
1 


1 
1 


CS-2 
CS-2 


48.0 (330) 
60.0 (415) 


30.0 (205) 
35.0 (240) 


1 
1 
1 


1 
1 

2 


CS-2 
CS-2 
CS-3 


48.0 (330) 
60.0 (415) 
70.0 (485) 


30.0 (205) 
35.0 (240) 
40.0 (275) 


1 


1 


CS-1 


47.0 (325) 


26.0 (180) 


1 


1 


CS-2 


60.0 (415) 


37.0 (255) 



(6) 



9.6 (66.2) 
12.0 (82.7) 

9.6 (66.2) 
12.0 (82.7) 
14.0 (96.5) 

9.4 (64.8) 

12.0 (82.7) 



72 



2007 SECTION IV 



TABLE HF-300.1 
MAXIMUM ALLOWABLE STRESS VALUES FOR FERROUS MATERIALS, ksi (MPa) (CONT'D) 

(Multiply by 1,000 to Obtain psi) 



Spec. 
No. 



Grade 











Spec. Min. 


Spec. Min. 








External 


Tensile 


Yield 


Nominal 




Group 


Pressure 


Strength, 


Strength, 


Composition 


P-No. 


No. 


Chart 


ksi (MPa) 


ksi (MPa) 



Note(s) 



Max. Allow. 

Stress Value, 

ksi (MPa) 



Pipe and Tubes (Cont'd) 
Electric Resistance Welded Carbon Steel 



SA-53 


A 


Carbon steel 


SA-53 


B 


Carbon steel 


SA-135 


A 


Carbon steel 


SA-135 


B 


Carbon steel 


SA-178 


A 


Carbon steel 


SA-178 


C 


Carbon steel 


Butt Welded 







1 


1 


CS-2 


48.0 (330) 


30.0 (205) 


(7) 


8.2 (56.3) 


1 


1 


CS-2 


60.0 (415) 


35.0 (240) 


(7) 


10.2 (70.3) 


1 


1 


CS-2 


48.0 (330) 


30.0 (205) 


(7) 


8.2 (56.3) 


1 


1 


CS-2 


60.0 (415) 


35.0 (240) 


(7) 


10.2 (70.3) 


1 


1 


CS-1 


47.0 (325) 


26.0 (180) 


(6)(7) 


8.0 (55.1) 


1 


1 


CS-2 


60.0 (415) 


37.0 (255) 


(7) 


10.2 (70.3) 



SA-53 



Carbon steel 



48.0 (330) 30.0 (205) 



(8) 



5.8 (39.7) 



Forgings 






Carbon Steels 




SA-105 




Carbon steel 


SA-181 


Class 60 


Carbon steel 


SA-181 


Class 70 


Carbon steel 


SA-266 


1 


Carbon steel 


SA-266 


2 


Carbon steel 


SA-266 


3 


Carbon steel 


Castings 






Carbon Steels 




SA-216 


WCA 


Carbon steel 


SA-216 


WCB 


Carbon steel 


Bolting 






Carbon Steels 





1 


2 




70.0 (485) 


36.0 (250) 


1 


1 


CS-2 


60.0 (415) 


30.0 (205) 


1 


2 


CS-2 


70.0 (485) 


36.0 (250) 


1 


1 


CS-2 


60.0 (415) 


30.0 (205) 


1 


2 


CS-2 


70.0 (485) 


36.0 (250) 


1 


2 


CS-2 


75.0 (515) 


37.5 (260) 



1 1 CS-2 60.0 (415) 30.0 (205) (9) 

1 2 CS-2 70.0 (485) 36.0 (250) (9) 



14.0 (96.5) 
12.0 (82.7) 
14.0 (96.5) 
12.0 (82.7) 
14.0 (96.5) 
15.0 (103.0) 



9.6 (66.2) 
11.2 (77.2) 



SA-307 B Carbon steel 

SA-193 B5 5Cr-V 2 Mo 

SA-193 B7 lCr-0.2Mo 

SA-311 1018, Class A Carbon steel 

SA-311 1035, Class A Carbon steel 

SA-311 1045, Class A Carbon steel 

SA-311 1045, Class B Carbon steel 

SA-311 1050, Class A Carbon steel 



SA-320 


L7 


lCr-0.2Mo 


SA-320 


L43 


l^Ni-^Cr-VfcMo 


SA-325 


1 


Carbon steel 


SA-354 


BC 


Carbon steel 


SA-354 


BD 


Carbon steel 



60.0 (415) 
100.0 (690) 
100.0 (690) 



125.0 (860) 
125.0 (860) 



(10) 


7.0 (48.3) 


(10) 


25.0 (172.0) 


(10) 


25.0 (172.0) 


(ll)(lla) 


14.0 (96.5) 


(lib) 


13.0 (89.6) 


(ll)(lla) 


17.0 (117.0) 


(lib) 


16.0 (110.0) 


(ll)(lla) 


19.0 (131.0) 


(lib) 


18.0 (124.0) 


(lD(lla) 


23.0 (159.0) 


(ll)(lla) 


20.0 (138.0) 


(lib) 


19.0 (131.0) 


(10) 


25.0 (172.0) 


(10) 


25.0 (172.0) 


(10) 


7.0 (48.3) 


(10) 


25.0 (172.0) 


(10) 


25.0 (172.0) 



73 



2007 SECTION IV 



TABLE HF-300.1 
MAXIMUM ALLOWABLE STRESS VALUES FOR FERROUS MATERIALS, ksi (MPa) (CONT'D) 

(Multiply by 1,000 to Obtain psi) 















Spec. Min. 


Spec. Min. 
















External 


Tensile 


Yield 




Max. Allow. 


Spec. 




Nominal 




Group 


Pressure 


Strength, 


Strength, 




Stress Value, 


No. 


Grade 


Composition 


P-No. 


No. 


Chart 


ksi (MPa) 


ksi (MPa) 


Note(s) 


ksi (MPa) 



Bars and Stays 
Carbon Steels 



SA-36 

SA-675 

SA-675 

SA-675 

SA-675 

SA-675 

SA-675 



45 
50 
55 
60 
65 
70 (483) 



Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 



58.0 (400) 
45.0 (310) 
50.0 (345) 
55.0 (380) 
60.0 (415) 
65.0 (450) 
70.0 (485) 



(1) 



11.6 (80.0) 
9.0 (62.1) 
10.0 (68.9) 
11.0(75.8) 
12.0 (82.7) 
13.0 (89.6) 
14.0 (96.5) 



Plate 
Alloy Steel 



SA-240 304 18Cr-8Ni 8 1 HA-1 

SA-240 304L 18Cr-8Ni 8 1 HA-3 

SA-240 316 16Cr-12Ni-2Mo 8 1 HA-2 

SA-240 316L 16Cr-12Ni-2Mo 8 1 HA-4 

SA-240 316Ti 16Cr-12Ni-2Mo-Ti 8 1 HA-2 

SA-240 439 18Cr-Ti 7 2 

SA-240 S44400 18Cr-2Mo 7 2 CS-2 

SA-240 S43932 18Cr-Ti-Co 7 2 CS-2 



75.0 (515) 
70.0 (485) 
75.0(515) 
70.0 (485) 
75.0 (515) 
60.0 (415) 
60.0 (415) 



30.0 (205) 
25.0 (170) 
30.0 (205) 
25.0(170) 
30.0(205) 
30.0(205) 
40.0 (275) 



(12) 
(12) 
(12) 
(12) 
(12) 
(13)(14)(15) 
(13X16) 



65.0 (450) 30.0 (205) (13)(14)(15) 



15.0 (103.0) 
14.0 (96.5) 
15.0(103.0) 
14.0 (96.5) 
15.0(103.0) 
13.0(82.7) 
12.0 (82.7) 
13.0 (89.6) 



Tube 
Alloy Steel 



SA-213 TP304 Smls. 18Cr-8Ni 

SA-213 TP304L Smls. 18Cr-8Ni 

SA-213 TP316 Smls. 16Cr-12Ni-2Mo 

SA-213 TP316L Smls. 16Cr-12Ni-2Mo 

SA-249 TP304 Wld. 18Cr-8Ni 

SA-249 TP304L Wld. 18Cr-8l\li 

SA-249 TP316 Wld. 16Cr-12Ni-2Mo 

SA-249 TP316L Wld. 16Cr-12l\li-2Mo 

SA-268 S44400 18Cr-2Mo 

SA-268 TP439 18Cr-Ti 

SA-268 S44735 Smls. 29Cr-4Mo 

SA-268 S44735 Wld. 29Cr-4Mo 



8 


1 


HA-1 


75.0 (515) 


30.0 (205) 


(17X18X12) 


15.0 (103.0) 


8 


1 


HA-3 


70.0 (485) 


25.0 (170) 


(17X18X12) 


14.0 (96.5) 


8 


1 


HA-2 


75.0 (515) 


30.0 (205) 


(17X18X12) 


15.0 (103.0) 


8 


1 


HA-4 


70.0 (485) 


25.0 (170) 


(17X18X12) 


14.0 (96.5) 


8 


1 


HA-1 


75.0 (515) 


30.0 (205) 


(7X17X18X12) 


12.8 (103.0) 


8 


1 


HA-3 


70.0 (485) 


25.0 (170) 


(7X17X18X12) 


11.9 (96.5) 


8 


1 


HA-2 


75.0 (515) 


30.0 (205) 


(7X17X18X12) 


12.8 (103.0) 


8 


1 


HA-4 


70.0 (485) 


25.0(170) 


(7X17X18X12) 


11.9 (96.5) 


7 


2 


CS-2 


60.0 (415) 


40.0 (275) 


(13X16) 


12.0 (82.7) 


7 


2 


CS-2 


60.0 (415) 


30.0 (205) 


(13X14X15) 


12.0(82.7) 


10J 


1 


CS-2 


75.0 (515) 


60.0 (415) 


(19) 


15.0 (103.0) 


10J 


1 


CS-2 


75.0 (515) 


60.0 (415) 


(7X19) 


15.0 (103.0) 



Pipe 
Alloy Steel 



SA-312 
SA-312 
SA-312 

SA-312 



TP304 
TP304L 
TP316 

TP316L 



Smls. 18Cr-8l\li 

Smls. 18Cr-8Ni 

Smls. 16Cr-12l\li- 

2Mo 

Smls. 16Cr-12Ni- 

2Mo 



8 
8 
8 


1 
1 
1 


HA-1 
HA-3 
HA-2 


75.0 (515) 
70.0 (485) 
75.0 (515) 


30.0 (205) 
25.0 (170) 
30.0 (205) 


(18X12) 
(18X12) 
(18X12) 


15.0(103.0) 
14.0 (96.5) 
15.0 (103.0) 


8 


1 


HA-4 


70.0 (485) 


25.0(170) 


(18X12) 


14.0 (96.5) 



74 



2007 SECTION IV 



TABLE HF-300.1 
MAXIMUM ALLOWABLE STRESS VALUES FOR FERROUS MATERIALS, ksi (MPa) (CONT'D) 

(Multiply by 1,000 to Obtain psi) 













External 


Spec. Min. 
Tensile 


Spec. Min. 
Yield 




Max. Allow. 


Spec. 
No. 


Grade 


Nominal 
Composition 


P-No. 


Group 
No. 


Pressure 
Chart 


Strength, 
ksi (MPa) 


Strength, 
ksi (MPa) 


Note(s) 


Stress Value, 
ksi (MPa) 


Pipe 
Alloy Steel 


















SA-312 


TP304 


Wld. 18Cr-8l\li 


8 


1 


HA-i 


75.0 (515) 


30.0 (205) 


(7)(18)(12) 


12.8 (87.9) 


SA-312 


TP304L 


Wld. 18Cr-8Ni 


8 


1 


HA-3 


70.0 (485) 


25.0 (170) 


(7)(18)(12) 


11.9(82.0) 


SA-312 


TP316 


Wld. 16Cr-12Ni-2Mo 


8 


1 


HA-2 


75.0(515) 


30.0 (205) 


(7)(18)(12) 


12.8 (87.9) 


SA-312 


TP316L 


Wld. 16Cr-12IMi-2Mo 


8 


1 


HA-4 


70.0 (485) 


25.0 (170) 


(7)(18)(12) 


11.9(82.0) 


Bar 




















Alloy Steel 


















SA-479 


S44400 


18Cr-2Mo 


7 


2 




60.0 (415) 




(13K16) 


12.0 (82.7) 


SA-479 


439 


18Cr-Ti 


7 


2 


HA-27 


70.0 (485) 


40.0 (275) 


(13)(14)(15) 


14.0 (96.5) 


SA-479 


304L 


18Cr-8Ni 


8 


1 


HA-3 


70.0 (485) 


25.0(170) 


(17M12) 


14.0 (96.5) 


SA-479 


316L 


16Cr-12Ni-2Mo 


8 


1 


HA-4 


70.0 (485) 


25.0(170) 


(17)(12) 


14.0 (96.5) 


SA-479 


304 


18Cr-8Ni 


8 


1 


HA-1 


75.0 (515) 


30.0 (205) 


(10K12K20) 


15.0 (103.0) 


SA-479 


ER308 


20Cr-10Ni 






HA-2 


75.0 (515) 


30.0 (205) 


(10)(12)(20) 


15.0(103.0) 


SA-479 


309S 


23Cr-12Ni 


8 


2 


HA-2 


75.0 (515) 


30.0 (205) 


(10)(12)(20) 


15.0 (103.0) 


SA-479 


309H 


23Cr-12Ni 


8 


2 


HA-2 


75.0 (515) 


30.0 (205) 


(10)(12)(20) 


15.0 (103.0) 


SA-479 


310S 


25Cr-20Ni 


8 


2 


HA-2 


75.0(515) 


30.0 (205) 


(10)(12)(20) 


15.0(103.0) 


SA-479 


316 


16Cr-12Ni-2Mo 


8 


1 


HA-2 


75.0 (515) 


30.0(205) 


(10)(12)(20) 


15.0 (103.0) 


Forgings 
Alloy Steel 


















SA-182 


F304 


18Cr-8Ni 


8 


1 


HA-1 


75.0 (515) 


30.0 (205) 


(18)(12)(21) 


15.0(103.0) 


SA-182 


F304L 


18Cr-8Ni 


8 


1 


HA-3 


70.0 (485) 


25.0 (170) 


(18)(12)(21) 


14.0 (96.5) 


SA-182 


F316 


16Cr-12l\li-2Mo 


8 


1 


HA-2 


75.0 (515) 


30.0 (205) 


(18)(12)(21) 


15.0(103.0) 


SA-182 


F316L 


16Cr-12Ni-2Mo 


8 


1 


HA-4 


70.0 (485) 


25.0(170) 


(18)(12)(21) 


14.0 (96.5) 


Castings 
Alloy Steel 


















SA-351 


CF8C 


18Cr-10Ni-Cb 


8 


1 




70.0 (485) 




(9)(12)(22) 


11.2 (77.2) 


SA-351 


CF3M 


16Cr-12Ni-2Mo 


8 


1 




70.0 (485) 




(9K12K22) 


11.2 (77.2) 



75 



2007 SECTION IV 



TABLE HF-300.1 
MAXIMUM ALLOWABLE STRESS VALUES FOR FERROUS MATERIALS, ksi (MPa) (CONT'D) 

(Multiply by 1,000 to Obtain psi) 

NOTES: 

(1) These allowable stress values apply also to structural shapes. 

(2) SA/CSA-G40.21 as specified in Section IIA, grade 38W or 44W, may be used in lieu of SA-36 for plates and bars not exceeding % in. 
(20 mm). For use at the same maximum allowable stress values as SA-36. 

(3) For thicknesses up to % in. (9.52 mm), inclusive. 

(4) For thicknesses over % in. to 0.580 in. (9.5 mm to 14.7 mm), inclusive. 

(5) For thicknesses over 0.580 to 0.750 in. (14.7 mm to 19.0 mm), inclusive. 

(6) Tensile value is expected minimum. 

(7) The stress value includes a joint factor of 0.85. 

(8) The stress value includes a joint factor of 0.60. 

(9) The stress value includes a casting quality factor of 0.80. Increased casting quality factors as a result of material examination beyond the 
requirements of the material specifications shall not be permitted. 

(10) The stress value is established from a consideration of strength only and will be satisfactory for average service. For bolted joints, where 
freedom from leakage over a long period of time without retightening is required, lower stress values may be necessary as determined from 
the relative flexibility of the flange and bolts, and corresponding relaxation properties. 

(11) For tie-rods and draw bolts on cast-iron sectional boilers subject to system pressure. Welding is not permitted. 

(a) To 7 / 8 in. (22 mm) diam. incl. 

(b) Over 7 / 8 in. to lV 4 in. incl. (22 mm to 32 mm). 

(c) To 3 in. (76 mm) incl. 

(12) The water temperature shall not exceed 210°F (98°C). 

(13) The maximum thickness of material covered by this Table is % in. (9.5 mm). 

(14) The service temperature shall not exceed 200°F (93°C). 

(15) Filler metal shall be Type 430 with a nominal titanium content of approximately 1.25%. The 300 series of chromium-nickel-iron filler 
metals shall not be used in welding vessels conforming to the requirements of Section IV. 

(16) Filler metal shall be Type 430 with a nominal molybdenum content of approximately 2%. The 300 series of chromium-nickel-iron filler 
metals shall not be used in welding vessels conforming to the requirements of Section IV. 

(17) Tubing material shall be fully annealed. 

(18) Limitations of HF-204.2 also apply. 

(19) Heat treatment after forming or fabrication is neither required nor prohibited. 

(20) For arc or resistance welded studs only. 

(21) These allowable stresses apply only to material 5 in. (127 mm) and under in thickness. 

(22) The minimum thickness for header material is 0.10 in. (2.6 mm). 



76 



07 



TABLE HF-300.2 

MAXIMUM ALLOWABLE STRESS VALUES FOR NONFERROUS MATERIALS, ksi 

(multiply by 1000 to obtain psi) 



Spec. Spec. Maximum Allowable Stress Value, ksi 

Min. Min. 

External Tensile Yield 

Pressure Strength, Strength, Up To 

Class/Condition/Temper P-No. Chart ksi ksi Note(s) 100°F 150 200 250 300 350 400 450 500 



Alloy 
Designation 
Spec. No. UNS No. 



Product Form 



Aluminum Bronze 

SB-Ill C60800 Smls. Condenser Tubes 



Annealed/061 



35 NFC-2 50.0 19.0 



10.0 10.0 10.0 10.0 10.0 9.9 



Copper 






SB-42 


C10200 


Pipe 


SB-42 


C10200 


Pipe 



SB-42 



C10200 



Pipe 



Annealed/061 31 NFC-1 

Hard Drawn/H80 - \ in. 31 NFC-4 

to 2 in. NPS, incl. 

Light Drawn/H55 - l\ in. 31 NFC-3 

to 12 in. NPS, incl. 



30 
45 



36 



9 

40 



30 



(1) 6.0 5.1 4.9 4.8 4.7 4.0 3.0 

(2X1) 9.0 9.0 9.0 9.0 8.8 8.3 4.3 



(2X1) 



7.2 7.2 7.2 7.2 7.0 6.8 6.6 



SB-75 


C10200 


Smls. Tubes 




Annealed/050/060 


31 


NFC-1 


30 


9 


(1) 


6.0 


5.1 


4.9 


4.8 


4.7 


4.0 


3.0 


SB-75 


C10200 


Smls. Tubes 




Light Drawn/H55 


31 


NFC-3 


36 


30 


(2)(1) 


7.2 


7.2 


7.2 


7.2 


7.0 


6.8 


6.6 


SB-75 


C10200 


Smls. Tubes 




Hard Drawn/H80 


31 


NFC-4 


45 


40 


(2)(1) 


9.0 


9.0 


9.0 


9.0 


8.8 


8.3 


4.3 


SB-Ill 


C10200 


Smls. Condenser 


Tubes 


Light Drawn/H55 


31 


NFC-6 


36 


30 


(1) 


7.2 


7.2 


7.2 


7.2 


7.0 


6.8 


6.6 


SB-Ill 


C10200 


Smls. Condenser 


Tubes 


Hard Drawn/H80 


31 


NFC-4 


45 


40 


(1) 


9.0 


9.0 


9.0 


9.0 


8.8 


8.3 


4.3 


SB-152 


C10200 


Plate, Sheet, Str 


ip, & Bar 


Hot Rolled/025, Annealed 


31 


NFC-1 


30 


10 


(1) 


6.0 


5.6 


5.4 


5.2 


5.0 


4.0 


3.0 


SB-283 


C37700 


Forging Brass 




As Forged/MlO/Mll 






46 


15 


(3X4) 


9.2 


9.2 


9.0 










SB-395 


C10200 


Smls. Tubes 




Light Drawn/H55 


31 


NFC-6 


36 


30 


(2X1) 


7.2 


7.2 


7.2 


7.2 


7.0 


6.8 


6.6 


Copper-Silicon 


































SB-96 


C65500 


Plate & Sheet 




Annealed/061 


33 


NFC-2 


50 


18 


(5) 


10.0 


10.0 


10.0 


10.0 


10.0 


5.0 


3.7 


SB-98 


C65500 


Rods 




Soft Anneal/060 


33 




52 


15 


(5) 


10.0 


10.0 


9.9 


9.8 


9.7 


5.0 


3.7 


SB-98 


C65500 


Rods 




Quarter Hard/HOl 


33 




55 


24 


(5) 


11.0 


11.0 


11.0 


11.0 


11.0 


8.0 


3.8 


SB-98 


C65100 


Rods 




Soft Anneal/060 


33 




40 


12 


(5) 


8.0 


7.9 


7.9 


7.9 


7.9 


5.0 


3.7 


SB-98 


C65100 


Rods 




Half Hard/H02 


33 




55 


20 


(5) 


11.0 


11.0 


11.0 


11.0 


11.0 


8.0 


3.8 


SB-315 


C65500 


Pipe & Tube 




Annealed/030/061 


33 


NFC-2 


50 


15 


(5) 


10.0 


10.0 


9.9 


9.8 


9.7 


5.0 


3.7 


Red-Brass 


































SB-43 


C23000 


Smls. Pipe 




Annealed/061 


32 


NFC-2 


40 


12 




8.0 


8.0 


8.0 


8.0 


8.0 


7.0 


4.8 


SB-Ill 


C23000 


Smls. Condenser Tubes 


Annealed/061 


32 


NFC-2 


40 


12 




8.0 


8.0 


8.0 


8.0 


8.0 


7.0 


4.8 


SB-395 


C23000 


Smls. Condenser 


Tubes 


Annealed/061 


32 


NFC-2 


40 


12 




8.0 


8.0 


8.0 


8.0 


8.0 


7.0 


4.8 



TABLE HF-300.2 
MAXIMUM ALLOWABLE STRESS VALUES FOR NONFERROUS MATERIALS, ksi (CONT'D) 

(multiply by 1000 to obtain psi) 



Spec. No. 



Alloy 

Designation 

UNS No. 



Product Form 



Spec. Spec. 

Min. Min. 

External Tensile Yield 

Pressure Strength, Strength, 

Class/Condition/Temper P-No. Chart ksi ksi 



Maximum Allowable Stress Value, ksi 



Up To 
Note(s) 100°F 150 200 250 300 350 400 450 



500 



Admirality 
SB-395 
SB-395 
SB-395 

SB-171 
SB-171 
SB-171 

Naval Brass 
SB-171 

Copper-Nickel 
SB-Ill 
SB-Ill 
SB-Ill 

SB-171 

SB-171 

SB-395 
SB-395 
SB-395 

SB-466 
SB-466 
SB-466 

Nickel-Copper 
SB-164 

SB-164 

SB-165 
SB-165 



C44300 Smls. Condenser Tubes 

C44400 Smls. Condenser Tubes 

C44500 Smls. Condenser Tubes 

C44300 Plates, < 4 in. 

C44400 Plates, < 4 in. 

C44500 Plates, < 4 in. 



C46400 



Plates, < 3 in. 



C70600 Smls. Condenser Tubes 

C71000 Smls. Condenser Tubes 

C71500 Smls. Condenser Tubes 

C70600 Plates, < 5 in. 

C71500 Plates, < l\ in. 

C70600 Smls. Condenser Tubes 

C71000 Smls. Condenser Tubes 

C71500 Smls. Condenser Tubes 

C70600 Pipe & Tube 

C71000 Pipe & Tube 

C71500 Pipe & Tube 



N04400 Bar 

N04400 Rounds 

IM04400 Smls. Pipe & Tube, 

5 in. O.D. max. 

N04400 Smls. Pipe & Tube, 

Over 5 in. O.D. 



Annealed/061 
Annealed/061 
Annealed/061 



32 


NFC-2 


45 


32 


NFC-2 


45 


32 


NFC-2 


45 


32 


NFC-2 


45 


32 


NFC-2 


45 


32 


NFC-2 


45 



32 



Annealed/061 
Annealed/061 
Annealed/061 



34 



34 



NFC-2 



NFC-3 



NFC-4 



50 



34 


NFC-3 


40 


34 


NFC-3 


45 


34 


NFC-4 


52 



40 



50 



Annealed/061 


34 


NFC-3 


40 


Annealed/061 


34 


NFC-3 


45 


Annealed/061 


34 


NFC-4 


52 


Annealed 


34 


NFC-3 


38 


Annealed 


34 


NFC-3 


45 


Annealed 


34 


NFC-4 


52 


Hot or Cold Worked, 


42 


NFN-3 


70 


Annealed 








Hot Worked (As Worked 


42 


NFN-3 


80 


or Stress Relieved) 








Annealed 


42 


NFN-3 


70 


Annealed 


42 


NFN-3 


70 



15 


9.0 


9.0 


9.0 


9.0 


9.0 


9.0 


3.5 


15 


9.0 


9.0 


9.0 


9.0 


9.0 


9.0 


3.5 


15 


9.0 


9.0 


9.0 


9.0 


9.0 


9.0 


3.5 


15 


9.0 


9.0 


9.0 


9.0 


9.0 


9.0 


3.5 


15 


9.0 


9.0 


9.0 


9.0 


9.0 


9.0 


3.5 


15 


9.0 


9.0 


9.0 


9.0 


9.0 


9.0 


3.5 



20 



15 
16 
18 

15 

20 

15 
16 
18 

13 
16 
18 



25 
40 

28 
25 



(6) 
(6) 

(6) 
(6) 



10.0 10.0 10.0 10.0 10.0 6.3 2.5 



8.0 8.0 7.9 7.6 7.3 7.1 6.9 6.7 6.6 

9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 

10.4 10.4 10.4 10.4 10.4 10.4 10.3 10.1 9.9 

8.0 8.0 7.9 7.6 7.3 7.1 6.9 6.7 6.6 

10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 

8.0 8.0 7.9 7.6 7.3 7.1 6.9 6.7 6.6 

9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 

10.4 10.4 10.4 10.4 10.4 10.4 10.3 10.1 9.9 

7.6 7.6 7.5 7.2 6.9 6.7 6.5 6.4 6.3 

9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 

10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 9.9 



14.0 14.0 14.0 14.0 13.6 13.3 13.2 13.1 13.1 

16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 16.0 

14.0 14.0 14.0 14.0 14.0 14.0 14.0 14.0 14.0 

14.0 14.0 14.0 14.0 13.6 13.3 13.2 13.1 13.1 



TABLE HF-300.2 
MAXIMUM ALLOWABLE STRESS VALUES FOR NONFERROUS MATERIALS, ksi (CONT'D) 

(multiply by 1000 to obtain psi) 



Alloy 
Designation 
Spec. No. UNS No. 



Product Form 



Spec. Spec. 

Min. Min. 

External Tensile Yield 

Pressure Strength, Strength, 

Class/Condition/Temper P-No. Chart ksi ksi 



Maximum Allowable Stress Value, ksi 



Up To 
Note(s) 100°F 150 200 250 300 350 400 450 500 



Nickel-Copper (Cont'd) 
SB-165 N04400 



Smls. Pipe & Tube, All 
Sizes 



Stress Relieved 



42 



NFN-3 



85 



55 



(6) 



17.0 17.0 17.0 17.0 17.0 17.0 17.0 17.0 17.0 



Integrally Finned Tubes 
SB-359 

Casting, Bronze and Brass 



SB-61 


C92200 


Steam or Valve Bronze 


SB-62 


C83600 


85-5-5-5 Composition 
Brass 


SB-584 


C84400 


81-3-7-9 Composition 
Semi-red Brass 


SB-584 


C90300 


88-8-0-9 Tin Bronze 



Casting, Bronze, Brass, and Aluminum 
SB/EN 1706 AISilOMg(a) Castings 
EN AC4300 



21.8 



(7) 



NFN-1 


34 


16 


(8) 


NFC-1 


30 


14 


(8) 




29 


13 


(8) 




40 


18 


(8) 



5.4 5.4 5.4 5.4 5.4 5.4 4.7 

6.0 6.0 6.0 6.0 6.0 5.8 5.7 5.6 5.5 

4.6 4.6 4.6 4.5 4.3 4.1 4.0 

5.1 5.1 5.1 5.1 5.1 5.1 5.1 



11.6 (8)(9) 4.6 4.4 4.4 4.3 4.3 3.9 



Nickel-Iron-Chromium 

SB-409 N08810 Plate 

SB-409 N08800 Plate 



Sol. Annealed 
Annealed 



45 
45 



NFN-9 
NFN-8 



65 
75 



25 (10) 13.0 13.0 13.0 13.0 13.0 13.0 12.9 12.8 12.8 
30 (10) 15.0 



NOTES: 

(1) When material is to be welded, the phosphorus deoxide types should be specified. 

(2) When nonferrous materials conforming to specifications given in Section II are used in welded or brazed construction, the maximum allowable working stresses shall not exceed the values 
given herein for the material in the annealed condition. 

(3) For use in HG-307.2(b) eq. (2), the maximum allowable stress at room temperature (100°F, max.) shall be 10.0 ksi (through 1V2 in. thickness) and 9.2 ksi (over l l / 2 in. thickness). 

(4) No welding or brazing permitted. 

(5) Copper-silicon alloys are not always suitable when exposed to certain median and high temperatures, particularly steam above 212°F. Therefore this material is limited to the construction 
of hot water boilers to be operated at a temperature not to exceed 200°F. 

(6) To be used for HLW connections only. 

(7) Use in accordance with HF-204 and HF-204.1. 

(8) The stress value includes a casting quality factor of 0.80. Increased casting quality factors as a result of material examination beyond the requirement of the material specification shall 
not be permitted. This is not intended to apply to valves and fittings made to recognized standards. 

(9) The maximum water temperature shall not exceed 200°F. 

(10) The maximum water temperature shall not exceed 210°F. 



07 



TABLE HF-300.2M 
MAXIMUM ALLOWABLE STRESS VALUES FOR NONFERROUS MATERIALS, MPa 



Spec. Spec. Maximum Allowable Stress Value, MPa 

Min. Min. 

External Tensile Yield 

Pressure Strength, Strength, Up To 

Class/Condition/Temper P-No. Chart MPa MPa Note(s) 40°C 65 100 125 150 175 200 225 250 



Spec. 
No. 



Alloy 

Designation 

UNS No. 



Product Form 



Aluminum Bronze 

SB-Ill C60800 Smls. Condenser Tubes Annealed/061 



35 NFC-2 345 



131 



68.9 68.9 68.9 68.9 68.9 68.4 65.8 



Copper 



SB-42 


C10200 


Pipe 




Annealed/061 


31 


NFC-1 


205 


62 


(1) 


41.4 


35.0 


33.4 


32.9 


32.3 


27.8 


21.7 




SB-42 


C10200 


Pipe 




Hard Drawn/H80 - % in. 
to 2 in. IMPS, incl. 


31 


NFC-4 


310 


275 


(2X1) 


62.1 


62.1 


62.1 


62.1 


60.3 


57.1 


36.3 




SB-42 


C10200 


Pipe 




Light Drawn/H55 - 2V 2 in. 
to 12 in. NPS, incl. 


31 


NFC-3 


250 


205 


(2X1) 


49.6 


49.6 


49.6 


49.6 


48.1 


46.9 


45.7 




SB-75 


C10200 


Smls. Tubes 




Annealed/050/060 


31 


NFC-1 


205 


62 


(1) 


41.4 


35.0 


33.4 


32.9 


32.3 


27.8 


21.7 


to 

e 


SB-75 


C10200 


Smls. Tubes 




Light Drawn/H55 


31 


NFC-3 


250 


205 


(2X1) 


49.6 


49.6 


49.6 


49.6 


48.1 


46.9 


45.7 


o 


SB-75 


C10200 


Smls. Tubes 




Hard Drawn/H80 


31 


NFC-4 


310 


275 


(2X1) 


62.1 


62.1 


62.1 


62.1 


60.3 


57.1 


36.3 


VI 

H 

n 

H 

o 
z 


SB-Ill 


C10200 


Smls. Condenser 


Tubes 


Light Drawn/H55 


31 


NFC-6 


250 


205 


(1) 


49.6 


49.6 


49.6 


49.6 


48.1 


46.9 


45.7 


SB-Ill 


C10200 


Smls. Condenser 


Tubes 


Hard Drawn/H80 


31 


NFC-4 


310 


275 


(1) 


62.1 


62.1 


62.1 


62.1 


60.3 


57.1 


36.3 


SB-152 


C10200 


Plate, Sheet, Strip, & Bar 


Hot Rolled/025, Annealed 


31 


NFC-1 


205 


70 


(1) 


41.4 


38.9 


37.1 


35.7 


34.1 


27.8 


21.7 


3 


SB-283 


C37700 


Forging Brass 




As Forged/MlO/Mll 






315 


105 


(3X4) 


63.4 


63.4 


61.3 












SB-395 


C10200 


Smls. Tubes 




Light Drawn/H55 


31 


NFC-6 


250 


205 


(2X1) 


49.6 


49.6 


49.6 


49.6 


48.1 


46.9 


45.7 




Copper-Sili 


con 


































SB-96 


C65500 


Plate & Sheet 




Annealed/061 


33 


NFC-2 


345 


125 


(5) 


68.9 


68.9 


68.9 


68.9 


68.9 


35.3 


27.1 




SB-98 


C65500 


Rods 




Soft Anneal/060 


33 




360 


105 


(5) 


68.9 


68.6 


68.0 67.4 


66.7 


35.3 


27.1 




SB-98 


C65500 


Rods 




Quarter Hard/HOl 


33 




380 


165 


(5) 


75.8 


75.8 


75.8 


75.8 


75.8 


58.4 


29.2 




SB-98 


C65100 


Rods 




Soft Anneal/060 


33 




275 


83 


. (5) 


55.2 


54.3 


54.3 


54.3 


54.1 


35.3 


27.1 




SB-98 


C65100 


Rods 




Half Hard/H02 


33 




380 


140 


(5) 


75.8 


75.8 


75.8 


75.8 


75.8 


58.4 


29.2 




SB-315 


C65500 


Pipe & Tube 




Annealed/030/061 


33 


NFC-2 


345 


105 


(5) 


68.9 


68.6 


68.0 


67.4 


66.7 


35.3 


27.1 




Red Brass 




































SB-43 


C23000 


Smls. Pipe 




Annealed/061 


32 


NFC-2 


275 


83 




55.2 


55.1 


55.1 


55.1 


55.1 


50.0 


36.3 




SB-Ill 


C23000 


Smls. Condenser Tubes 


Annealed/061 


32 


NFC-2 


275 


83 




55.2 


55.1 


55.1 


55.1 


55.1 


50.0 


36.3 




SB-395 


C23000 


Smls. Condenser Tubes 


Annealed/061 


32 


NFC-2 


275 


83 




55.2 


55.1 


55.1 


55.1 


55.1 


50.0 


36.3 





TABLE HF-300.2M 
MAXIMUM ALLOWABLE STRESS VALUES FOR NONFERROUS MATERIALS, MPa (CONT'D) 



Spec. 
No. 



Alloy 

Designation 

UNS No. 



Product Form 



Spec. Spec. 

Min. Min. 

External Tensile Yield 

Pressure Strength, Strength, 

Class/Condition/Temper P-No. Chart MPa MPa Note(s) 



Up To 
40°C 



Maximum Allowable Stress Value, MPa 



65 100 125 150 175 200 225 250 



Admirality 
SB-395 
SB-395 
SB-395 

SB-171 
SB-171 
SB-171 

Naval Brass 



C44300 Smls. Condenser Tubes Annealed/061 

C44400 Smls. Condenser Tubes Annealed/061 

C44500 Smls. Condenser Tubes Annealed/061 

C44300 Plates, < 100 mm 

C44400 Plates, < 100 mm 

C44500 Plates, < 100 mm 



32 NFC-2 310 105 

32 NFC-2 310 105 

32 NFC-2 310 105 

32 NFC-2 310 105 

32 NFC-2 310 105 

32 NFC-2 310 105 



SB-171 


C46400 


Plates, < 75 mm 




32 


NFC-2 


345 


140 


Copper-Nicke 
















SB-Ill 


C70600 


Smls. Condenser Tubes 


Annealed/061 


34 


NFC-3 


275 


105 


SB-Ill 


C71000 


Smls. Condenser Tubes 


Annealed/061 


34 


NFC-3 


310 


110 


SB-Ill 


C71500 


Smls. Condenser Tubes 


Annealed/061 


34 


NFC-4 


360 


125 


SB-171 


C70600 


Plates, < 125 mm 




34 


NFC-3 


275 


105 


SB-171 


C71500 


Plates, < 64 mm 




34 


NFC-4 


360 


140 


SB-395 


C70600 


Smls. Condenser Tubes 


Annealed/061 


34 


NFC-3 


275 


105 


SB-395 


C71000 


Smls. Condenser Tubes 


Annealed/061 


34 


NFC-3 


310 


110 


SB-395 


C71500 


Smls. Condenser Tubes 


Annealed/061 


34 


NFC-4 


360 


125 


SB-466 


C70600 


Pipe & Tube 


Annealed 


34 


NFC-3 


260 


90 


SB-466 


C71000 


Pipe & Tube 


Annealed 


34 


NFC-3 


310 


110 


SB-466 


C71500 


Pipe & Tube 


Annealed 


34 


NFC-4 


345 


125 


Nickel-Copper 
















SB-164 


N04400 


Bar 


Hot or Cold Worked, 
Annealed 


42 


NFN-3 


485 


170 


SB-164 


N04400 


Rounds 


Hot Worked (As Worked 
or Stress Relieved) 


42 


NFN-3 


550 


275 


SB-165 


N04400 


Smls. Pipe & Tube, 
125 mm O.D. max. 


Annealed 


42 


NFN-3 


485 


195 


SB-165 


N04400 


Smls. Pipe & Tube, 
Over 125 mm O.D. 


Annealed 


42 


NFN-3 


485 


170 


SB-165 


N04400 


Smls. Pipe & Tube, 
All sizes 


Stress Relieved 


42 


NFN-3 


585 


380 



62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 


62.1 



62.1 62.1 27.7 

62.1 62.1 27.7 

62.1 62.1 27.7 

62.1 62.1 27.7 

62.1 62.1 27.7 

62.1 62.1 27.7 



68.9 68.9 68.9 68.9 68.9 45.4 19.9 



55.2 55.2 54.0 52.1 50.3 48.8 47.5 46.5 45.7 

62.1 62.1 62.1 62.1 62.1 62.1 62.1 62.1 62.1 
71.7 71.7 71.7 71.7 71.7 71.7 71.4 70.1 68.9 

55.2 55.2 54.0 52.1 50.3 48.8 47.5 46.5 45.7 

68.9 68.9 68.9 68.9 68.9 68.9 68.9 68.9 68.9 

55.2 55.2 54.0 52.1 50.3 48.8 47.5 46.5 45.7 

62.1 62.1 62.1 62.1 62.1 62.1 62.1 62.1 62.1 

71.7 71.7 71.7 71.7 71.7 71.7 71.4 70.1 68.9 

52.4 52.4 51.3 49.5 47.8 46.3 45.1 44.2 43.5 

62.1 62.1 62.1 62.1 62.1 62.1 62.1 62.1 62.1 

68.9 68.9 68.9 68.9 68.9 68.9 68.9 68.9 68.9 



(6) 96.5 96.5 96.5 96.2 93.6 91.9 90.9 90.4 90.4 

(6) 110 110 110 110 110 110 110 110 110 

(6) 96.5 96.5 96.5 96.5 96.5 96.5 96.5 96.5 96.5 

(6) 96.5 96.5 96.5 96.2 93.6 91.9 90.9 90.4 90.4 

(6) 117 117 117 117 117 117 117 117 117 



TABLE HF-300.2M 
MAXIMUM ALLOWABLE STRESS VALUES FOR NONFERROUS MATERIALS, MPa (CONT'D) 



Spec. 
No. 



Alloy 

Designation 

UNS No. 



Product Form 



Spec. Spec. 
Min. Min. 

External Tensile Yield 

Pressure Strength, Strength, Up To 

Class/Condition/Temper P-No. Chart MPa MPa Note(s) 40°C 65 



Maximum Allowable Stress Value, MPa 



100 125 150 175 200 225 250 



Integrally Finned Tubes 
SB-359 



(7) 



Casting, Bronze and Brass 



SB-61 
SB-62 

SB-584 

SB-584 



C92200 
C83600 

C84400 

C90300 



Steam or Valve Bronze 
85-5-5-5 Composition 

Brass 
81-3-7-9 Composition 

Semi-red Brass 
88-8-0-9 Tin Bronze 



Casting, Bronze, Brass, and Aluminum 
SB/EN 1706 AISilOMg(a) Castings 
EN AC4300 

Nickel-Iron-Chromium 

SB-409 N08810 Plate 

SB-409 N 08800 Plate 



Sol. Annealed 
Annealed 



(8) 37.5 37.5 37.5 37.5 37.5 37.5 33.4 

(8) 41.4 41.4 41.4 41.4 41.3 40.2 39.2 

(8) 32.0 32.0 31.9 30.6 29.3 28.3 27.7 

(8) 35.3 35.3 35.3 35.3 35.3 35.3 35.3 



150.0 80.6 (8)(9) 24.0 24.0 24.0 24.0 24.0 



NFN-1 


235 


110 


NFC-1 


205 


97 




200 


90 




275 


125 



45 


NFN-9 


450 


170 


45 


NFN-8 


520 


210 



(10) 89.6 89.6 89.6 89.6 89.6 89.6 89.2 88.7 88.3 
(10) 103 



NOTES: 

(1) When material is to be welded, the phosphorus deoxidized types should be specified. 

(2) When nonferrous materials conforming to specifications given in Section II are used in welded or brazed construction, the maximum allowable working stresses shall not exceed the values 
given herein for the material in the annealed condition. 

(3) For use in HG-307.2(b) eq.(2), the maximum allowable stress at room temperature (40°C, max.) shall be 68.9 MPa (through 38 mm thickness) and 63.4 MPa (over 38 mm thickness). 

(4) No welding or brazing permitted. 

(5) Copper-silicon alloys are not always suitable when exposed to certain median and high temperatures, particularly steam above 100°C. Therefore this material is limited to the construction 
of hot water boilers to be operated at a temperature not to exceed 93°C. 

(6) To be used for HLW connections only. 

(7) Use in accordance with HF-204 and HF-204.1. 

(8) The stress value includes a casting quality factor of 0.80. Increased casting quality factors as a result of material examination beyond the requirement of the material specification shall 
not be permitted. This is not intended to apply to valves and fittings made to recognized standards. 

(9) The maximum water temperature shall not exceed 93°C. 

(10) The maximum water temperature shall not exceed 96°C. 



2007 SECTION IV 



TABLE HF-301.1 

MINIMUM ALLOWABLE 

THICKNESS OF FERROUS SHELL PLATES 

Minimum Ferrous Material 

Thickness Allowable Under 

Rules, in. (mm) 





Tubesheet or 




Diameter or Width of Shell, 


Head With 


Shell 


Tubesheet, or Head, in. (mm) 


Rolled Tubes 


Plate 


42 (1 050) or under 


5 /ie (8) 


V 4 (6) 
[Note (1)] 


Over 42 to 60 (1 050 to 1 500) 


X (9.5) 


5 /i fe (8) 


Over 60 to 78 (1 500 to 1 950) 


7 / 16 (ll) 


% (9.5) 


Over 78 (1 950) 


V 2 (13) 


7 / 16 (11) 



NOTE: 

(1) Shell plate 3 / 16 in. (4.8 mm) thickness is permissible for cylindrical 
shells 24 in. (600 mm) in diameter or less, and for a maximum 
allowable working pressure not over 30 psi (207 kPa). 

TABLE HF-301.2 
MINIMUM ALLOWABLE THICKNESS OF NONFERROUS SHELL PLATES 





Minimum 


Nonferrous Material Thickness Allowable Under Rules, in. 


(rrm 


l) 


Diameter or Width of Shell, 


Tubesheet 


or Head 


Shell Plate 




Tubesheet, or Head, in. (mm) 


Copper, Admiralty, 




Copper-Nickel 


Copper, Admiralty, 




Copper-Nickel 


[Note (1)] 


and Red Brass 




Alloy 


and Red Brass 




Alloy 


24 (600) or under 


3 / 16 (5.0) [Note (2)] 




% 2 (4.0) [Note (2)] 


V 8 (3.0) 




3 / 32 (2.5) 


Over 24 to 36 (600 to 900) 


V 4 (6.0) [Note (2)] 




3 / 16 (5.0) [Note (2)] 


3 /i6 (5.0) 




V 8 (3.0) 


Over 36 to 42 (900 to 1 050) 


5 / 16 (8.0) 




\ (6.0) [Note (2)] 


\ (6.0) 




3 /i6 (5.0) 


Over 42 to 60 (1 050 to 1 500) 


% (9.5) 




% (9.5) 


5 / 16 (8.0) 




5 / 16 (8.0) 


Over 60 to 78 (1 500 to 1 950) 


7 / 16 (11.0) 




7 / 16 (11.0) 


% (9.5) 




% (9.5) 


Over 78 (1 950) 


V 2 (13.0) 




\ (13.0) 


7 / 16 (11.0) 




7 / 16 (11.0) 



NOTES: 

(1) For the purpose of applying Tables HF-301.1 and HF-301.2 to a noncylindrical boiler, the equivalent shell diameter shall be taken as the 
width of the unsupported portion of any plate, measured before stays are installed. 

(2) See HF-301.2(c). 



83 



2007 SECTION IV 



PART HF — SUBPART HW 

REQUIREMENTS FOR BOILERS 

FABRICATED BY WELDING 



ARTICLE 4 
GENERAL REQUIREMENTS 



HW-400 SCOPE 

The requirements of this Subpart HW are applicable to 
boilers and parts thereof that are fabricated by welding. 



HW-401 RESPONSIBILITY OF 
MANUFACTURER OR 
CONTRACTOR 

Each manufacturer or contractor is responsible for the 
welding done by his organization and shall establish the 



procedures and conduct the tests required in Section IX to 
qualify the welding procedures he uses in the construction 
of the weldments built under Section IV and the perform- 
ance tests of welders and welding operators who apply 
these procedures. 

It should be noted that the use of standard welding 
procedures is acceptable. All requirements for the use of 
these procedures shall be in accordance with Section IX. 
The use of these procedures shall be addressed in the 
manufacturer's or contractor's Quality Control Manual and 
shall be available for review by the Authorized Inspector. 



84 



2007 SECTION IV 



ARTICLE 5 
MATERIAL REQUIREMENTS 



HW-500 PERMISSIBLE MATERIALS 

Materials used in welded construction of pressure parts 
shall conform to one of the specifications given in Section 
II and shall be limited to those for which allowable stress 
values are given in Tables HF-300.1 and HF-300.2 and for 
which weld group P-Numbers are assigned in Section IX. 

(a) Carbon or alloy steel having a carbon content of 
more than 0.35% shall not be used in welded construction 
or be shaped by oxygen cutting or other thermal cutting 
processes. 

(b) Stud material for arc stud welding and resistance 
stud welding of carbon steel shall be low carbon steel of 
an acceptable material in this Section and with a carbon 
maximum of 0.27% and with a minimum tensile strength 
of 60,000 psi (400 MPa). See further limits in HW-730.4 
and HW-820. 



(c) Materials joined by the inertia and continuous drive 
friction welding processes shall be limited to materials 
assigned P-Numbers in Section IX and shall not include 
rimmed or semikilled steel. 



HW-501 MATERIALS OF DIFFERENT 
SPECIFICATIONS 

Two materials of different specifications may be joined 
by welding provided the requirements of QW-251.2 of 
Section IX are met. 



HW-502 MATERIALS FOR SMALL PARTS 

Small parts used in welded construction under the provi- 
sions of HF-203.1 shall be of good weldable quality. 



85 



2007 SECTION IV 



ARTICLE 6 
WELDING PROCESSES AND QUALIFICATIONS 



HW-600 WELDING PROCESSES 

The welding processes that may be used under this Part 
shall meet all the requirements of Section IX and are 
restricted to the following: 

(a) arc or gas welding processes are restricted to 
shielded metal arc, submerged arc, gas metal arc, gas tung- 
sten arc, plasma arc, atomic hydrogen metal arc, laser 
beam, electronic beam, and oxyfuel gas welding 

(b) pressure welding processes are restricted to flash, 
induction, resistance, pressure thermit, pressure gas, and 
inertia and continuous drive friction welding 

(c) definitions are given in Section IX that include varia- 
tions of these processes 



qualified, except that performance qualification by radiog- 
raphy, in conformance with Section IX, QW-304 for weld- 
ers or QW-305 for welding operators, may be performed 
within the first 3 ft (1 m) of the first production weld. 



HW-612 INTERCHANGE OF QUALIFYING 
TESTS AMONG MANUFACTURERS 
PROHIBITED 

The performance qualification tests for welders and 
welding operators conducted by one manufacturer or con- 
tractor shall not qualify a welder or welding operator to 
do work for any other manufacturer or contractor. 



HW-610 WELDING QUALIFICATIONS 

Unless specified otherwise for a particular process, the 
procedures, the welders, and the welding operators used 
in welding pressure parts and in joining nonpressure parts 
(attachments) to pressure parts shall be qualified in accor- 
dance with Section IX. When the welding process attaching 
non-pressure parts that have essentially no load-carrying 
function (such as extended heat transfer surfaces) is auto- 
matic, procedure and performance qualification testing is 
not required. 



HW-611 NO PRODUCTION WORK WITHOUT 
QUALIFICATIONS 

No production work shall be undertaken until the proce- 
dures, the welders, and the welding operators have been 



HW-613 MAINTENANCE OF RECORDS OF 
QUALIFICATIONS AND 
IDENTIFYING MARKS 

The Manufacturer or contractor shall maintain qualifica- 
tion records of the welding procedures, welders, and weld- 
ing operators employed by him showing the date and results 
of test and the identification mark assigned to each welder. 
These records shall be certified to by the Manufacturer or 
contractor by signature or some other method of control in 
accordance with the Manufacturer's quality control system, 
and be accessible to the Inspector. The welder or welding 
operator shall stamp his identification mark on or adjacent 
to all welded joints made by him at intervals of not greater 
than 3 ft (1 m), or the Manufacturer shall keep a record 
of the welded joints on a vessel and the welders and welding 
operators used in making the joints. 



86 



2007 SECTION IV 



ARTICLE 7 
DESIGN OF WELDMENTS 



HW-700 DESIGN OF WELDED JOINTS 
HW-701 GENERAL REQUIREMENTS 

All welds, fillet or full penetration, shall be made to a 
qualified welding procedure by qualified welders for each 
welding process employed (manual, semiautomatic, auto- 
matic), in accordance with the applicable provisions of 
Section IX to assure satisfactory penetration and fusion 
into the base metal to the root of the weld. All members, 
prior to being welded, shall be properly fitted, aligned, 
and retained in position in accordance with the procedure 
specification for the welding procedure to be used. 

HW-701.1 Butt Joints. Longitudinal, circumferential, 
and other joints uniting plates of a drum, shell, or other 
pressure parts, except as provided in HW-701.1, 
HW-701.2, HW-701.3, HW-710, HW-711, and HW-712, 
shall be butt joints. A butt joint shall be double-welded 
butt or may have filler metal added from one side only, 
provided the weld penetration is complete and there is 
reinforcement on both sides of the joint. There shall be no 
valley either on the edge or in the center of the joint and 
the weld shall be so built up that the weld metal shall 
present a gradual increase in thickness from the surface of 
the plate to the center of the weld. At no point shall the 
plate on one side of the joint be offset with the plate on 
the other side of joint in excess of the alignment tolerance 
in HW-812 except as provided in HW-7 15(a)(2). 

(a) A tapered transition section having a length not less 
than three times the offset between the adjoining surfaces 
as shown in Fig. HW-701.1, shall be provided at joints 
between materials that differ in thickness by more than 
one-fourth of the thickness of the thinner material or by 
more than !/ 8 in. (3.0 mm). The transition section may be 
formed by any process that will provide a uniform taper. 
The weld may be partly or entirely in the tapered section or 
adjacent to it as indicated in Fig. HW-701.1. The transition 
requirement also applies when there is a reduction in thick- 
ness within a cylindrical shell course and to tapers within 
formed heads. In longitudinal shell joints, the middle lines 
of the adjoining thicknesses shall be in alignment within 
the fabricating tolerances specified in HW-812. 

(b) Where fusion welded steel plate boilers are made 
up of two or more courses, the welded longitudinal joints of 
adjacent courses shall be not less than 6 in. (150 mm) apart. 



FIG. HW-701.1 BUTT WELDING OF PLATES OF 
UNEQUAL THICKNESS 




Tapered one 
side only 
(inside or 
outside) 




(a) 


(b) 


(c) 


Preferred Method 


Permissible 


Not 


(Center lines 


(Circumferential 


Permissible 


coincide) 


joints only) 





HW-701.2 Lap Joints 

(a) Boilers designed for not more than 30 psi (200 kPa) 
and having inside diameters not exceeding 24 in. (600 mm) 
I.D. may have longitudinal or circumferential joints uniting 
plates of a shell made with lap joints, provided the joint 
is not in direct contact with the products of combustion. 

(b) For boilers over 30 psi (200 kPa) or 24 in. (600 mm) 
I.D., lap joints may be used only where stayed plates are 
joined, where a cylindrical shell and a stayed wrapper are 
joined, or as permitted in HW-711. 

(c) Except as permitted in HW-701. 4 and HW-71 1, lap 
joints shall be full fillet welded inside and outside and the 
throats of the fillet welds shall be not less than 0.7 times 
the thickness of the thinner plate. The surface overlap shall 
be not less than 4 times the thickness of the thinner plate. 

HW-701.3 Corner or Tee Joints 

(a) Boilers designed for not more than 30 psi (200 kPa) 
may have the corner or tee joints made with single full 
fillet welds. The throat of the fillet weld shall be not less 
than 0.7 times the thickness of the thinner plate joined [see 
Fig. HW-701.3, sketches (a), (b), and (c)]. 



87 



2007 SECTION IV 



FIG. HW-701.3 SOME FORMS OF ATTACHMENTS OF PRESSURE PARTS TO FLAT 
PLATES TO FORM A CORNER JOINT (TEE JOINT) 



■* mm. t n 



-* fh 



(a) 







■< min. t m 












1 — M 








IV ' 






t 


s 








< T h 





(b) 




min. t n 



(0 



Not less than 1.25f s 
but need not be greater than t h 




min. 2f c 



Backing strip may be used 




(d) 



Backing strip 
may be used 



(e) 



Not permissible 



a i + a 2 = 2f m where 
3t is not less than 0.5a 2 
nor greater than 2a 2 

(f) 

tf, = nominal head thickness 
t m = lesser of t s or tf, 
t s = nominal shell thickness 

GENERAL NOTES: 

(a) Illustrations (a), (b), and (c) are permissible for boilers for pressures up to 30 psi (200 kPa). 

(b) Illustrations (d), (e), or (f) are required for boilers designed for pressures over 30 psi (200 kPa). 

(c) Illustration (g) is not permissible. 



(g) 



2007 SECTION IV 



(b) Hot water boilers designed to these rules for pres- 
sures in excess of 30 psi (200 kPa) shall have corner or 
tee joints made only with full penetration welds [see Fig. 
HW-701.3, sketches (d) and (e)] or double full fillet welds 
[see Fig. HW-701.3, sketch (f)]. 

HW-701.4 Single Fillet Joints for Lap Attachment 
of U-Bend Tubes. Tubes bent to a nominal 180 deg to 
form a U-bend may be attached to headers by fillet welds 
provided 

(a) the header is not larger than NPS 3 (DN 80) 

(b) the maximum thickness of the parts being joined is 
\ in. (10 mm) 

(c) the tubes are inserted, coaxially with a forced fit for 
a minimum distance of 1.5 times the minimum thickness 
of the parts being joined, into the end of the header and 
are attached by fillet welds 

(d) the fillet welds are deposited from the outside only 
with one leg not smaller than the thickness of the header 
and the other leg not smaller than 1 .3 times the thickness 
of the thinnest part being joined, and 

(e) the fillet weld shall not be in contact with primary 
furnace gasses 

HW-702 JOINT EFFICIENCIES 

The following joint efficiencies E are to be used in e., 
HG-301 and HG-305 for joints completed by an arc or gas 
welding process: 

(a) E = 85% for full penetration butt joints as attained 
by double welding or by other means that will obtain the 
same quality of deposited weld metal on the inside and 
outside weld surfaces, to provide complete joint penetration 
and assurance that the weld grooves are completely filled 
(HW-701.1). Welds that use metal backing strips that 
remain in place are excluded. 

(b) E = 80% for full penetration single-welded butt 
joints with backing strips other than those included in (a) 
above. 

(c) E = 60% for single-welded butt joints without use 
of backing strips. 

(d) E = 65% for double full fillet lap joints meeting 
the requirements of HW-701.2(b). 

(e) E = 49% for double full fillet lap joints meeting 
the requirements of HW-701.2(a). 

HW-702.1 Joint Efficiencies for External Pressure 
Design. Joint efficiency E factors are not required to be 
used when the boiler part is designed for external pres- 
sure only. 

HW-703 MINIMUM THICKNESS OF WELDED 
PARTS 

The minimum thicknesses specified in HF-301 and 
Tables HF-301.1 and HF-301. 2 apply if greater than the 



thicknesses calculated utilizing the above listed joint effi- 
ciency factors with formulas of this Section. 

HW-710 WELDED STAYS 

HW-710.1 Insertion of Stays. Except as provided in 
HW-710.4 and HW-710.5, the stays are to be inserted 
through holes having a maximum gap around the periphery 
of the stay of V l6 in. (1.5 mm). The size of the weld in 
shear, measured parallel to that portion of the stay in or 
extended through the plate, shall be not less than 5 / 16 times 
the required diameter of the stay and in no case less than 
V 4 in. (6 mm). For a stay with other than circular cross 
section, the minimum size of the weld shall be that calcu- 
lated for a circular stay of the same cross-sectional area. 
To provide for the above specified welding, the plate may 
be countersunk by machining or pressing, or the stay may 
protrude through the plates, or a combination of those 
methods may be used. The end of the stay shall not be 
covered by weld metal and shall not be below the surface 
of the plate. 

HW-710.2 Projection of Stays Exposed to Products 
of Combustion. The ends of stays inserted through plates 
shall not project more than 3 /g in. (10 mm) beyond surfaces 
exposed to the products of combustion. 

HW-710.3 Fit-Up and Welding of Stays. The fit-up 
and welding shall be such that excessive weld deposits do 
not project beyond the surface of the plate at the root of 
the weld. 

HW-710.4 Welding of Diagonal Stays. Diagonal stays 
shall be attached to the inner surface of the shell, but not 
to a head or tubesheet, by fillet welds only provided the 
following [see Figs. HW-7 10.4(a) and HW-7 10.4(b)]: 

(a) Fillet welds shall be not less than 3 / 8 in. (10 mm) 
size and shall continue the full length of each side of the 
portion of the stay in contact with the shell. The product 
of the aggregate length of these fillet welds times their 
throat shall be not less than 1 .25 times the required cross- 
sectional area of the stay. A fillet weld across the end of 
the stay is optional but shall not be credited in calculating 
the required area of fillet welds. 

(b) The longitudinal center line of the stay (projected 
if necessary) shall intersect the surface of the plate to which 
the stay is attached within the outer boundaries of the 
attaching welds (also projected if necessary). 

(c) Diagonal stays shall, for boilers designed for not 
more than 30 psi (200 kPa) pressure, comply with the 
requirements of HW-710.1, HW-710.2, and HW-710.3 and 
shall, for boilers designed for pressures in excess of 30 psi 
(200 kPa), comply with the requirements of HW-710.5. 

HW-710.5 For Pressures in Excess of 30 psi 
(200 kPa). The stays shall be inserted into holes count- 
ersunk in the sheet except as provided in HW-710.4, and 
shall be attached by full penetration welds. 



89 



2007 SECTION IV 



FIG. HW-710.4(a) SOME ACCEPTABLE TYPES OF DIAGONAL STAYS FOR INSTALLATION BY WELDING 




GENERAL NOTE: A round bar or a round bar with a forged palm 



FIG. HW-710.4(b) UNACCEPTABLE TYPES OF DIAGONAL STAYS FOR INSTALLATION BY WELDING 




HW-711 HEADS OR TUBESHEETS 
ATTACHED BY WELDING 
HW-711. 1 Flanged Heads or Tubesheets. Boilers 
may be constructed by attaching an outwardly or inwardly 
flanged head or tubesheet to the shell by fillet welding 
provided 

(a) the head or tubesheet is supported by tubes, or 
braces, or both 

(b) the joint attaching an outwardly flanged head or 
tubesheet is wholly within the shell and forms no part 
thereof 

(c) inwardly flanged heads or tubesheets are full fillet 
welded inside and outside 

(d) the throats of the full fillet welds are not less than 
0.7 times the thickness of the head or tubesheet 

(e) on inwardly flanged heads or tubesheets, the mini- 
mum length of the straight flange shall conform with the 
requirements of HW-701.2 



(f) the shell at the weld is not in contact with primary 
furnace gases 

(g) these constructions shall not be used on the rear 
head of a horizontal-return tubular boiler, and inwardly 
flanged heads or tubesheets shall not be used on a boiler 
with an extended shell 

HW-711.2 Unflanged Heads or Tubesheets. Boilers 
may be constructed by attaching unflanged heads or tube- 
sheets to the shell by welding, provided 

(a) the head or tubesheet is supported by tubes or braces, 
or both, as required by HG-340, or its thickness is calcu- 
lated using the appropriate formula from HG-307 

(b) the welding for boilers designed for not more than 
30 psi (200 kPa) meets the minimum requirements for 
HW-701.3(a) 

(c) the weld for boilers designed for pressure in excess 
of 30 psi (200 kPa) is a full penetration weld applied from 



90 



2007 SECTION IV 



either or both sides as shown in Fig. HW-701.3, sketch 
(d) or (e), or a double full fillet weld as shown in Fig. 
HW-701.3, sketch (f) 

(d) the shell or wrapper sheet, where exposed to primary 
furnace gases and not water cooled, shall not extend beyond 
the outside face of the head or tubesheet for a distance 
greater than the thickness of the head or tubesheet 

(e) this construction shall not be used on the rear head 
of a horizontal-return tubular boiler 



HW-712 FURNACE ATTACHMENTS 

HW-712.1 For Pressures Not More Than 30 psi 
(200 kPa). A furnace or crown sheet in a boiler designed 
to these rules for pressures not more than 30 psi (200 kPa) 
may be attached to a head or tubesheet with a full fillet 
weld, provided 

(a) the furnace shall not extend beyond the outside face 
of the head or tubesheet for a distance greater than the 
thickness of the head or tubesheet, unless protected by 
refractory material; the furnace shall be trimmed to remove 
any excess material before welding 

(b) the throat of the full fillet weld is not less than 0.7 
times the thickness of the head or tubesheet 

(c) the joint attaching a cylindrical furnace to a head or 
tubesheet is wholly outside the cylindrical portion of the 
furnace 

HW-712.2 For Pressures in Excess of 30 psi 
(200 kPa). A furnace or crown sheet in a hot water boiler 
designed to these rules for pressures in excess of 30 psi 
(200 kPa) shall be attached to a head or tubesheet, as shown 
in Fig. HW-701.3, by a full penetration weld, with the 
furnace or crown sheet extending at least through the full 
thickness of the head or tubesheet, but when exposed to 
primary gases, furnace or crown sheet projections shall not 
extend beyond the face of the plate by more than \ in. 
(10 mm), unless protected by refractory material. 



HW-713 TUBES ATTACHED BY WELDING 

(a) The edge of the plate at the tubesheet hole may be 
beveled or recessed. The depth of any bevel or recess shall 
not be less than the tube thickness. Where the plate is 
beveled or recessed, the projection of the tubes beyond the 
tube sheet shall not exceed a distance equal to the tube 
thickness, but shall extend at least through the tubesheet. 

(b) The maximum and minimum distance the firetube 
shall extend through the tubesheet shall be in accordance 
with Table HW-713. 

(c) The minimum fillet weld throat plus groove weld 
depth (if present) shall be no smaller than the tube thick- 
ness. For tubes that are not exempt from calculations as 
stays by HG-346(c), the area of the weld in shear measured 



parallel to the axis of the tube at the outside diameter of 
the tube shall additionally not be less than 1 .25 times the 
cross-sectional area of the tube required by HG-342.1. 

(d) The above projections do not apply to watertubes; 
the maximum projection for watertubes is \ in. (13 mm). 
For attachment of watertubes by welding, see HW-731. 

HW-715 HEAD-TO-SHELL ATTACHMENTS 

Ellipsoidal, torispherical, hemispherical, and other types 
of formed heads, concave or convex to the pressure shall 
have the following requirements as to skirt length. 

(a)(1) An ellipsoidal or torispherical head that is 
attached to a shell by a butt joint need not be provided 
with a skirt when the nominal head thickness does not 
exceed \\ times the nominal shell thickness. When the 
nominal head thickness exceeds \\ times the nominal 
shell thickness, a skirt shall be provided having a length 
not less than three times the nominal head thickness or 
\\ in. (38 mm), whichever is smaller. When a skirt is 
used it shall meet the requirements for shell thickness in 
HG-301. 

(2) Flanged heads concave to pressure may be 
attached to shells using a butt weld with one plate offset 
as shown in Fig. HW-715.1 provided the welded joint is 
not in contact with primary furnace gases. The offset shall 
be smooth and symmetrical and shall not be machined or 
otherwise reduced in thickness. There shall be a uniform 
force fit with the mating section at the root of the weld. 

(b) Ellipsoidal or torispherical heads, concave or convex 
to the pressure, shall have a skirt length not less than that 
shown in Fig. HW-715.1 provided the welded joint is not 
in contact with primary furnace gases. Heads that are fitted 
inside or over a shell shall have a driving fit before welding. 

(c) Formed heads of full hemispherical shape, concave 
to pressure, need not have an integral skirt, but where a 
skirt is provided for butt welded attachment, the thickness 
of the skirt shall be at least that required for a seamless 
cylindrical shell of the same diameter. 

(d) Flanged ellipsoidal or torispherical heads convex to 
pressure may be attached to the shell with a full fillet weld 
with throat no less than 0.7 times the head thickness. The 
shell at the weld shall not be in contact with primary 
furnace gases. 

HW-720 OPENINGS IN WELDS 

Any type of opening that meets the requirements for 
reinforcement given in HG-321 may be located in a butt 
welded joint. 

HW-730 WELDED CONNECTIONS 
HW-730.1 Strength of Attachment Welds 

(a) Nozzles, other connections, and their reinforcement 
may be attached to a boiler by arc or gas welding. Sufficient 



91 



2007 SECTION IV 



TABLE HW-713 
FIRETUBE EXTENSION THROUGH TUBESHEETS FOR WELDED CONSTRUCTION 



Tubes Exposed to Primary Furnace Gases 
[Note (1)] 



Tubes Not Exposed to Primary Furnace 
Gases [Note (1)] 



Tubesheet beveled or recessed 



Tubesheet not beveled or recessed 



min. = the tube shall extend at least 
through the tubesheet 

max. = tfube 

min. = t tU be 

max. = greater of t tube or \ in. (6 mm) 



min. = the tube shall extend at least 

through the tubesheet 
max. = greater of t tube or % in. (10 mm) 

min. = t tube 

max. = greater of t tube or % in. (10 mm) 



NOTE: 

(1) See HG-360.2. 



FIG. HW-715.1 HEADS ATTACHED TO SHELLS 



Tangent 
line — 



k 



2t h min., but not less than 1 / 2 in. (13 mm) 
for ellipsoidal heads 

2f h min. + 1 A> in. (13 mm) for other heads 



■yj— 1.3f s min. 



£Z 



*fi 



Hi' MMm™ 



■3t h min. + V2 in. (13 mm) 
but not less 
than 1 in. 




■ 2f s min. 
1.3f c min. 



Tangent 
line — 



"ZZZZZZZ 



-f- 3t h min. + 1 /2 in. h ~ 

(13 mm) Taper -' 

but not less optional 

than 1 in. (25 mm) 



W* 



3t h min., but need not exceed 
1 1 / 2 in.(38mm) 

r s min. 

a L 



(a) Single Fillet Weld 



Bevel optional 
f. 



x. 



~r 



2V 2 t max. 
1 f min. 

jl' 



' ~^ \ Avoid sharp break 



As desired 



IV2 f min 
for fs= 1 /2 (13 mm) max. 

(b) Butt Weld With One 
Plate Edge Offset 



Depth of offset = t s 
Pressure on this side 



r;/;/ 






t 
zzz 



1.3f s min. 
2f«.min. 



r 

(c) (d) 

(e) 

Details (c), (d), and (e) 
are not permissible 



welding shall be provided on either side of the line through 
the center of the opening parallel to the longitudinal axis 
of the shell to develop the strength of the shell as prescribed 
in HG-327 through shear or tension in the weld, whichever 
is applicable. The strength of groove welds shall be based 
on the area subjected to shear or to tension. The strength 
of fillet welds shall be based on the area subjected to 
shear, computed on the minimum leg dimension. The inside 
periphery of fillet weld shall be used in computing its 
length. 

(b) Weld strength calculations for pressure loadings are 
not required for the following: 

(1) nozzle connections made per Fig. HW-731, 
sketches (a), (b), (c), (g), (h), (o-l), (s-1), (u-1), (v-1), 
and (w-1) 

(2) nozzle connections for openings that are exempt 
from reinforcement requirements by HG-320.3(c) or 
HG-320.3(d), and 



(3) openings designed in accordance with the rules 
for ligaments in para. HG-350 

HW-730.2 Stress Values for Weld Metal. The allow- 
able stress values for groove and fillet welds and for shear 
in nozzle necks in percentages of stress values for the 
vessel material are as follows: 



Factor 



Percentage of Stress Values, 



Nozzle-wall shear 


70 


Groove-weld tension 


74 


Groove-weld shear 


60 


Fillet-weld shear 


49 



NOTE: These values are obtained by combining the following fac- 
tors:87^% for combined end and side loading, 80% for shear strength, 
and the applicable joint efficiency factors. 

HW-730.3 Telltale Holes in Reinforcement Plates 
and Saddles. Separate reinforcement plates and saddles 



92 



2007 SECTION IV 



used to reinforce the material around openings and that 
are attached to the outside of a boiler shall be provided 
with at least one telltale hole [maximum size: % in. (6 mm) 
pipe tap] that may be tapped for a preliminary compressed- 
air and soapsuds test for tightness of welds that seal off 
the inside of the boiler. These telltale holes may be left 
open when the boiler is in service. If the holes are plugged, 
the plugging material used shall not be capable of sus- 
taining pressure between the plate and the boiler wall. 

HW-730.4 Stud Welds. Arc stud welding and resist- 
ance stud welding, as defined in E- 101, where the boiler 
pressure exerts a tensile load on the studs, may be used 
only for the attachments of bolted unstayed flat heads, 
cover plates and blind flanges, handholes and manholes, 
with the further limitations as follows: 

(a) Studs attached by stud welding shall not be in direct 
contact with products of combustion or flue gases. 

(b) Where the pressure exerts a tensile load on the studs, 
a full face gasket must be used on flat heads, cover plates 
and blind flanges attached by stud welding. 

(c) The minimum size stud used shall be not less than 
V4 in. (6 mm) nominal diameter, and the maximum size 
shall not exceed 7 / 8 in. (22 mm) nominal diameter. 

( d) The type of stud shall be limited to round externally 
threaded studs. 

(e) Base metal shall be of ferrous material specification 
as permitted by this Section, and the base metal must be 
thick enough to prevent burn through. See HW-500(b) for 
stud material. 

(f) The maximum spacing of studs shall not exceed 
12 times the nominal diameter of the stud. 

(g) The maximum allowable stress for the stud shall be 
7800 psi (54 MPa) based on the smallest cross-sectional 
area (i.e., the root of the thread). 



HW-731 MINIMUM REQUIREMENTS FOR 
ATTACHMENT WELDS 

HW-731.1 General. The location and minimum size 
of attachment welds for nozzles and other connections shall 
conform to the requirements in this paragraph. 

(a) Notation. The symbols used in this paragraph and 
in Fig. HW-731 are defined as follows: 

t = nominal thickness of boiler shell or head 
t c = not less than the smaller of \ in. (6 mm) or 
0-7 fmin. (inside corner welds may be further 
limited by a lesser length of projection of noz- 
zle wall beyond the inside face of the boiler 
wall) 
f min = the smaller of 3 / 4 in. (19 mm) or the thickness 
of the thinner of the parts joined by a fillet, 
single-bevel, or single-J weld 
t„ = nominal thickness of nozzle wall 



t w = dimension of partial penetration attachment 
welds (fillet, single-bevel, or single-J), mea- 
sured as shown in Fig. HW-731 
t\, t 2 = not less than the smaller of V 4 in. (6 mm) or 
0-7?min and 1 1 + t 2 not less than 1 % t^ n 

HW-731.2 Necks Abutting the Boiler Shell 

(a) Nozzles abutting the boiler shell shall be attached 
by a full penetration groove weld. Backing strips shall be 
used with welds deposited from only one side when the 
shell thickness is over \ in. (10 mm) or when complete 
joint penetration cannot be verified by visual inspection 
[for example, see Fig. HW-731, sketch (y)]. 

(b) Nozzles or tubes recessed into thick boiler shells or 
headers may be welded from only one side by cutting a 
welding groove in the boiler shell to a depth of not less 
than t n on the longitudinal axis of the opening. It is recom- 
mended that a recess at least V 16 in. (1.5 mm) deep be 
provided at the bottom of the groove in which to center 
the nozzle. The dimension t w of the attachment weld shall 
be not less than t n or less than !/ 4 in. (6 mm) [for example, 
see Fig. HW-731, sketch (y)]. 

HW-731.3 Inserted Nozzles Without Added Rein- 
forcement Elements 

(a) Nozzles inserted into or through a hole cut in the 
boiler shell and without additional reinforcement elements 
shall be attached by a full penetration groove weld or by 
two partial penetration welds, one on each face of the boiler 
shell. Permissible types of welds are shown in 
Fig. HW-731, sketches (c) through (h). 

(b) Backing strips shall be used with full penetration 
welds deposited from one side only when the shell thick- 
ness is over \ in. (10 mm) or when complete joint penetra- 
tion cannot be verified by visual inspection. The two partial 
penetration welds may be any desired combination of fillet, 
single-bevel, and single-J welds. The dimension t w of each 
weld shall be not less than the smaller of V4 in. (6 mm) 
or O.ltmin and their sum shall be not less than 1 V4 r min (see 
Fig. HW-731). 

HW-731.4 Inserted Nozzles With Added Reinforce- 
ment. Inserted type nozzles having added reinforcement 
in the form of one or more separate reinforcement plates 
shall be attached by welds at the nozzle neck periphery 
and at the outer edge of each reinforcement plate. The 
weld at the outer edge of each reinforcement plate shall 
be a fillet weld with a minimum throat dimension of ^fmj n . 
The welds attaching the nozzle to the boiler shell and to 
the reinforcement shall consist of one of the following 
combinations: 

(a) a single-bevel or single-J weld in the shell plate, 
and a single-bevel or single-J weld in each reinforcement 
plate. The dimension t w of each weld shall be not less than 
0.7^ [see Fig. HW-731, sketch (n)]. 



93 



2007 SECTION IV 



FIG. HW-731 SOME ACCEPTABLE TYPES OF WELDS FOR FITTINGS, NOZZLES, AND 
OTHER CONNECTIONS TO SHELLS, DRUMS, AND HEADERS 




Backing strip if used may be removed after welding 





(a) 



(b) 



(c) 




(9) 





W) t. -t- *■- = n/.* m in (e-D 



ti + t 2 = 1 1 / 4 fmin. 
t, or t 2 not less than 
the smaller of V4 in. (6 mm) 
or OJt min. 





Typical flush type nozzles 



(e-2) 




/H, rrx 



> L 



(f) 



t IM = OJt min. 



V- 



< f 



i/ 2 t min. 





(h) 



(k) 



1 /2f nnin. 




1 /2f min. 



Weld to shell 



X\k 



Lm 



t uu = OJt min. 



■Weld to pad 




y l 2 t min 




(m) 



(n) 



94 



2007 SECTION IV 



FIG. HW-731 SOME ACCEPTABLE TYPES OF WELDS FOR FITTINGS, NOZZLES, AND 
OTHER CONNECTIONS TO SHELLS, DRUMS, AND HEADERS (CONT'D) 



^ 




Kr 



(o-1) 



^^ 



1 1 / 4 f min. — 
(o-2) 







Either method of attachment is satisfactory 
f c \, / \ t ^ / \ t r 




3 in. (75 mm) z l-$2 in - 

^ NPS max. 3 / 8 in . (10 mm) < 2 - 5 mm > 



(u-1) 



t 2 \ g C l 2 

t : + t 2 = IV4 t min 



^ 





(u-2) 



(v-1) (v-2) 



t w (not lesstha 
the thickness of 
schedule 160 pipe) 
t ! or 1 2 not less than the smaller of V4 in. (6 mm) or 0.7f min. 

(w-1) (w-2) (w-3) (w-4) 



min. leg 



T—Jl 



Z_IZ__aKZZJ 

V 

t„=0.7 t min. 



V2 f min. 



(x) 



(y) 




V16 m 1 f n 




,but 

not less than 
V4 in. (6 mm) 'A f c 

For nozzels or tubes recessed into thick 
boiler shells or headers [see HW-731.2 (b)] 
when used for other than square, round or 
oval headers, corners shall be rounded off. 



Nozzle or tube connections - 
[see HW-731. 2(b) and HW-731. 8] 



J 



(z) 



95 



2007 SECTION IV 



(b) a full penetration groove weld in the shell plate, and 
a fillet, single-bevel, or single-J weld with a weld dimen- 
sion t w not less than 0.7f m j n in each reinforcement plate 
[see Fig. HW-731, sketch (m)]. 

(c) a full penetration groove weld in each reinforcement 
plate, and a fillet, single-bevel, or single-J weld with a 
weld dimension t w not less than 0.7^ in the shell plate 
[see Fig. HW-731, sketch (1)]. 

HW-731.5 Nozzles With Integral Reinforcement. 

Nozzles and other connections having integral reinforce- 
ment in the form of extended necks or saddle type pads 
shall be attached by a full penetration weld or by means 
of a fillet weld along the outer edge and a fillet, single- 
bevel, or single-J weld along the inner edge. The throat 
dimension of the outer weld shall be not less than l^t^. 
The dimension t w of the inner weld shall be not less than 
0.7^ [see Fig. HW-731, sketch (k)]. 

HW-731.6 Fittings. The attachment of fittings shall 
meet the following requirements. 

(a) Except as provided for in HW-731. 7, fittings shall 
be attached by a full penetration groove weld or by two 
fillet or partial penetration welds, one on each face of the 
boiler wall. The minimum weld dimensions shall be as 
shown in Fig. HW-731, sketches (u) through (x). 

(b) Flange-type fittings not exceeding NPS 3 (DN 80) 
as shown in Fig. HW-731, sketch (w-4), may be attached 
without additional reinforcement other than that in the 
fitting and its attachments, provided all of the following 
conditions are met: 

(1) The boiler wall thickness shall not exceed \ in. 
(10 mm). 

(2) The minimum fillet leg shall be 3 / 32 in. (2.5 mm). 

(3) The opening in the boiler wall shall not exceed the 
outside diameter of the nominal pipe plus % in. (19 mm). 

HW-731.7 Fittings and Nozzles Not Exceeding NPS 3 
(DN 75) 

(a) Fittings, nozzles, or equivalent bolting pads may be 
attached to vessels having a wall thickness not greater than 
3 / 8 in. (10 mm) by a fillet weld deposited from the outside 
only, having the minimum dimensions shown in 
Fig. HW-731, sketches (o) through (t). 

(b) Fittings shown in Fig. HW-731, sketches (u-2), 
(v-2), (w-2), and (x), may be attached by welds that are 
exempt from size requirements other than those specified 
in HW-730.1. 

(c) Fittings may be attached by a groove and fillet weld 
from the outside only as shown in Fig. HW-731, sketch 
(w-3). The groove weld t w shall not be less than the thick- 
ness of Schedule 160 pipe (ANSI B36.10-1979). 

(d) Fittings and nozzles not exceeding NPS 1 !/ 2 (DN 40) 
as shown in Fig. HW-731, sketches (t-1) and (t-2) may be 
attached to vessels by a fillet weld deposited from the 
outside only provided the following conditions are met: 



(1 ) The boiler wall thickness shall not exceed \ in. 
(10 mm). 

(2) The fillet weld shall be a minimum of 0.7 1 instead 
of lV^min shown in Fig. HW-731, sketches (t-1) and (t-2), 
but in no case less than % 2 m - (2.5 mm) leg. 

HW-731.8 Watertube Attachments. Watertubes not 
exceeding 3 l / 2 in. (89 mm) O.D. may be attached to tube- 
sheets with fillet welds deposited from the outside only, 
having a minimum weld dimension as shown in 
Fig. HW-731, sketch (z) [see HG-360.3(d)]. 



HW-740 RESISTANCE WELDING IN CARBON 
STEEL FOR OTHER THAN BUTT 
WELDED JOINTS 

Resistance spot and seam welding may be used in the 
construction of embossed or dimpled assemblies under the 
following limitations and additional requirements: 

(a) Materials used in the resistance welded parts are 
SA-285 and SA-414 with the further limitation that the 
carbon content is 0.15 maximum on heat analysis. 

(b) Embossed or dimpled assemblies consist of either 
two embossed plates welded together, or two dimpled 
plates welded together, or an embossed or dimpled plate 
welded to a flat plate as in Fig. HW-745 sketch (a). A 
third, intermediate plate, frame, or series of spacers, as 
illustrated in Fig. HW-740, sketch (a) or (c), may be used 
to form a three-ply assembly. 

(c) The allowable working pressure for resistance 
welded embossed or dimpled assemblies shall be the lowest 
pressure established by the following: 

(1) a proof test in accordance with the requirements 
of HG-500. 

(2) the computed value of the plain plate, if used in 
resistance spot welded construction. The plain plate, if 
used, shall meet the requirements for braced and stayed 
surfaces in HG-340. 

(3) the computed value of the plain plate if used in 
resistance seam welded construction. The plain plate, if 
used, shall meet the requirements of HG-307.3(a), formulas 
(3) and (4), with z = 2.5 max., c = 0.2. 

(d) In lieu of the Procedure and Performance Qualifica- 
tion requirements of Section IX, the following require- 
ments shall be met for resistance spot welded and resistance 
seam welded pressure vessels. 

(1) Proof Test. A pressure proof test to destruction 
shall be conducted on a finished vessel or representative 
panel. The test shall be conducted as specified in HG-502.3. 
If a representative panel is used, it shall be rectangular in 
shape and at least 5 pitches in each direction, but not less 
than 24 in. (600 mm) in either direction. 

(2) Workmanship Samples 



96 



2007 SECTION IV 



FIG. HW-740 THREE-PLY JOINT ASSEMBLIES 



Edge seam 
weld 



Spot or seam 
welds" 




Three-Ply Assembly 



(a) Two outer Embossed or Dimpled Plates 
Welded to Inner Flat Plate 



Seam welds 



Spacer 



Spot welds 




Section A - A Section B - B 

Three-Ply Assembly 

(b) Two Outer Embossed Plates Welded 
to Inner Edge Frame and Spacers 



1 in. (25 mm) to 
1 1 /4 in. (32 mm) 



Filler as 
required for 
tension-test 
grip 



As required 



* 



H 



_1 in. (25 mmp" 
to 1 V 4 in. (32 mm) 



^ ^ 



(c) Spot-Weld Tension Specimen for 
Three-Ply Joint 



± 



1 in. (25 mm) to 
1V 4 in. (32 mm) 



± 

1 in. (25 mm) to 
1 1 / 4 in. (32 mm) 

T 



As required- 



H 



Macro-section on £ 
of seam weld 



_ 1 in. (25 mm) 

to 1V 4 in. (32 mm) 



(d) Seam Weld Specimen for Tension 
and Macro-section for Three-Ply Joint 



(a) Three single spot welded specimens, and /or 
one seam welded specimen, as shown in Fig. HW-745 for 
two-ply joints, and in Fig. HW-740 for three-ply joints, 
shall be made immediately before and after the welding 
of the proof test vessel. These test specimens shall be 
representative of the manufacturing practice employed in 
the fabrication of the proof test vessel. When a difference 
in the amount of magnetic material in the throat of the 
machine or the part geometry precludes the welding of 
satisfactory test specimens at the same machine settings 
as those used for the proof test vessel, sufficient material 
shall be placed in the throat of the welding machine to 
compensate for the difference in size of the proof test panel 
and the small test specimens. 

(b) The spot welded specimens shall be subjected 
to tensile loading for ultimate strength and visually 
inspected for nugget size, electrode indentation, and evi- 
dence of defects. The seam weld specimens shall be simi- 
larly tested for ultimate strength and prepared for 
macrographic examination to reveal nugget size, spacing, 
penetration, soundness, and surface conditions. 

(c) In addition, a typical spot weld sample and 
seam welded sample shall be cut from the proof test vessel 
after failure. A portion of each sample shall be sectioned 
for macroetch examination. 

( d) All pertinent information obtained from the 
foregoing tests shall be recorded. These samples and data 
constitute workmanship samples that shall be available for 
comparison with quality control specimens that may be 
made during production. 

(e) With every change in production run of mate- 
rial or gage, the machine setting control will be verified 
by test samples. 

(3) Machine Settings and Controls. The resistance 
welding machine settings and process control parameters 
used in the making of the proof test vessel and the work- 
manship samples shall be recorded. Except for minor varia- 
tions and adjustments as may be permitted at the discretion 
of the Authorized Inspector, the applicable settings shall 
be used in the fabrication of all vessels in a given produc- 
tion run. 

(4) Pressure Tests and Inspection. All production 
vessels shall be pressure tested to a pressure not less than 
1.5 times the allowable working pressure. These tests and 
inspection during fabrication shall be in accordance with 
HG-510. 

(5) Records. Records shall be kept of all data obtained 
from tests of the proof test vessel, the workmanship sam- 
ples, the welding machine settings, the welding procedure, 
and process control parameters. Records shall be kept of 
all preheat, postheat, and heat-treatment procedures and of 
inspection procedures. 

(6) If spot and seam welding machines other than 
those used for the initial proof test vessel and workmanship 



97 



2007 SECTION IV 



samples are to be used in production, each additional 
machine and welding procedure shall be qualified in full 
accordance with (d). The performance of the additional 
proof test vessels shall substantiate the allowable working 
pressure previously established for the specific boiler 
design. 

(7) Lap joints only, between two thicknesses of metal 
sheet, may be resistance spot or seam welded. The use of 
projection welding (including resistance stud welding) is 
excluded. 

( 8) The range of thickness of sheet materials that may 
be resistance spot or seam welded under this case shall be 
as follows 

(a)Two-Ply Joints [See Fig. HW-745, Sketch (a)] 

(1) The minimum thickness t± or t 2 shall be 
0.045 in. (1.14 mm). 

(2) The maximum thickness t\ or t 2 shall be V 4 in. 
(6 mm) nominal. 

(b)Three-Ply Joints [See Fig. HW-740, Sketches 
(a) and (b)] 

(1) The two outer layers t\ and t 2 shall be equal 
in thickness. 

(2) The inner layer t 3 shall be at least as thick 
as t\ or t 2 . 

(3) The minimum thickness of t u t 2 , and f 3 shall 
be 0.045 in. (1.14 mm). 

(4) The maximum thickness of t\ and t 2 shall be 
0.126 in. (3.20 mm). 

(5) The maximum thickness of f 3 shall be 
0.188 in. (4.8 mm). 

(6) The total thickness of the three layers t\ + 
t 2 + t 3 shall be 0.135 in. (3.43 mm) min., 0.378 in. 
(10 mm) max. 



HW-745 RESISTANCE WELDING OF 

HYDRAULICALLY FORMED PANELS 

Resistance spot and seam welding may be used in the 
construction of embossed or dimpled assemblies under the 
following limitations and additional requirements. 

(a) Materials used in the resistance welded parts of such 
vessels are carbon steel SA-285, SA-620, and SA-414, or 
any proven combination, with the further limitation that 
the carbon content is 0.15% maximum. 

(b) Construction consists of employing resistance spot 
welding or resistance seam welding to join two sheets 
together [see Fig. HW-740, sketch (a)]. Subsequent to the 
joining and sealing operation, the assembly is subjected to 
a hydraulic or pneumatic pressure to achieve a dimpled 
formation. 

Construction may consist of two sheets of equal thick- 
ness that results in the formation of a dimpled surface 
on both sides of an assembly or two sheets of different 



thicknesses that results in the formation of a dimpled sur- 
face on only one side of a pressure assembly. Any number 
of such assemblies may be joined together, by fusion weld- 
ing, to make a boiler or boiler parts. 

(c) The allowable working pressure for the construction 
shall be the lowest pressure established by the following: 

(1) a proof test in accordance with the bursting test 
procedures in HG-502 and HG-503 need not be followed, 
provided that when performing the proof test, the applica- 
tion of pressure is continuous until burst or until the proof 
test is stopped. In using the formulas for calculating the 
maximum allowable working pressure, a value of 0.80 
shall be used for E, the weld joint efficiency factor. All 
provisions of HG-501 and HG-504 shall apply. 

(2 ) the computed value of the plain plate, if used in 
resistance spot welded construction. The plain plate, if 
used, shall meet the requirements for braced and stayed 
surfaces in HG-340. 

(3) the computed value of the plain plate, if used in 
resistance seam welded construction. The plain plate, if 
used, shall meet the requirements of HG-307.3 formulas 
(3) and (4), with z = 2.5 max., c = 0.2, and E = 1.0. 

(d) The following design limitations apply: 

(1) A change in any of the following variables will 
require requalification of the design proof test of (c): 

(a) an increase in the spot or row pitch exceeding 
Vi6 in. (1.5 mm) 

(b) a change in the specification, type, or grade of 
material or material thickness for either sheet or both sheets 

(c) a change in the electrode size or material 

(2) A duplicate test panel of that used to establish 
the maximum allowable working pressure shall be inflated 
to a pressure at least 5% greater than the maximum forming 
pressure to be used in production. The rate of pressurization 
shall be the same as that used in the burst test. The panel 
shall be sectioned to show at least six spot welds [see 
Fig. HW-745, sketches (d-1) and (d-2)]. The weld cross 
sections shall be subjected to macroetch examinations and 
shall show no cracks. The maximum pillow heights mea- 
sured, as shown in Fig. HW-745, sketch (e), of panels 
made in production shall not exceed 95% of the maximum 
pillow height of this duplicate test panel. The maximum 
forming pressure shall not exceed 80% of the burst 
pressure. 

(e) In lieu of the Procedure Qualification requirements 
of Section IX, the following requirements shall be met for 
resistance spot welded and resistance seam welded panels. 

(1) Proof Test. A pressure proof test to destruction 
as set forth in (c)(1) above shall be conducted on a finished 
boiler or representative panel. This test may be a separate 
test or part of the test in (c)(1) above. If a representative 
panel is used, it shall be rectangular in shape and at least 
5 pitches in each direction, but not less than 24 in. (600 mm) 
in either direction. 



98 



2007 SECTION IV 



FIG. HW-745 TWO-PLY JOINT ASSEMBLIES 



Edge seam 
weld 



Spot or 
seam welds 



Edge seam 
we d 




Two-Ply Assembly 



Two Embossed or 
Dimpled Plates 



Embossed or Dimpled 
Plate to Flat Plate 



2 in. 
(50 mm) 
min. 



(a) 
As required 



-I 



Tension 



Macro-section 
on£ of 
seam weld 



Tension 



1 in. (25 mm) < D< 1V 4 in. (32 mm) 

(c) Seam-Weld Specimen for Tension and Macro-section, 
Two-Ply Joint 





Step (1) 



Step (2) 



Step 1: Grip specimen in vase or other suitable device. 



As required 




1 "* 





1 in. (25 mm) < D< 1 1 / 4 in. (32 mm) 
(b) Single-Spot-Weld Tension Specimen, Two-Ply Joint 




Pillow height 



(e) 




Step (3) 



Step 2: Bend specimen (this step may not be required if the gripped portion of the specimen is greatly thicker than the 
other portion). 

Step 3: Peel pieces apart with suitable tool until they are separated. 

(f) Peel Test 



99 



2007 SECTION IV 



(a) A typical spot weld sample and seam welded 
sample shall be cut from the proof test panel after failure. 
A portion of each sample shall be sectioned for macroetch 
examination. 

(2) Workmanship Samples 

(a) Three single spot welded specimens, and /or 
one seam welded specimen as shown in Fig. HW-745, 
sketches (b) and (c), shall be made immediately before 
and after the welding of the proof test panel. These test 
specimens shall be representative of the manufacturing 
practice employed in the fabrication of the proof test panel. 
When a difference in the amount of magnetic material in 
the throat of the welding machine or the part geometry 
precludes the welding of satisfactory test specimens at the 
same machine settings as those used for the proof test 
panel, sufficient material shall be placed in the throat of 
the welding machine to compensate for the difference in 
size of the proof test panel and the small test specimens. 

(b) The spot welded specimens shall be subjected 
to tensile loading for ultimate strength and visually 
inspected for nugget size, electrode indentation, and evi- 
dence of defects. The seam weld specimens shall be simi- 
larly tested for ultimate strength and prepared for 
macrographic examination to reveal nugget size, spacing, 
penetration, soundness, and surface condition. 

(c) All pertinent information obtained from the 
foregoing tests shall be recorded. These samples and data 
constitute workmanship samples that shall be available for 
comparison with quality control specimens that may be 
made during production. 

(d) With every change of material gage, the 
machine setting control shall be verified by test samples. 

(e ) At the beginning of each production run, which 
is a group of panels or assemblies all produced during a 
24 hr period using the same welding process, material, and 
material thickness, either a tension test or a peel test as 
shown in Fig. HW-745, sketch (f), shall be performed. The 
acceptance criterion for these tests shall be that the parent 
metal adjacent to the weld must fail before the weld 
itself fails. 

(3) Machine Settings and Controls. The resistance 
welding machine settings and process control parameters 
used in the making of the proof test panel and the workman- 
ship samples shall be recorded. Except for minor variations 
and adjustments as may be permitted at the discretion of 



the Inspector, the applicable settings shall be used in the 
fabrication of all panels in a given production run. 

(4) Pressure Tests and Inspection. All production 
boilers shall be pressure tested to a pressure not less than 
1.5 times the allowable working pressure. These tests and 
inspection during fabrication shall be in accordance with 
HG-510, except that provisions of HG-5 10(b) may be 
exceeded because the application of pressure during forma- 
tion of the pillows will exceed the design and test pressure 
by more than the allowed 10 psi (70 kPa). 

(5) Records. Records shall be kept of all data obtained 
from tests of the proof test boiler or panel, duplicate test 
panel, the workmanship samples, the welding machine set- 
tings, and the welding procedure and process control 
parameters. Records shall be kept of all preheat, postheat, 
and heat-treatment procedures and of inspection proce- 
dures. 

(f) If spot and seam welding machines other than those 
used for the initial proof test panel, duplicate test panel, 
and workmanship samples are to be used in production, 
each additional machine and welding procedure shall be 
qualified in accordance with (e)(2)(a) and (b) above. 

(g) Lap joints only, between two thicknesses of metal 
sheet, may be resistance spot or seam welded. The use of 
projection welding (including resistance stud welding) is 
excluded. 

(h) The range of thickness of sheet materials that may 
be resistance spot or seam welded shall be as follows for 
two-ply joints [see Fig. HW-745, sketch (a)]: 

(a) the minimum thickness t\ or t 2 shall be 0.045 
in. (1.14 mm) 

(b) the maximum thickness t\ or t 2 shall be V4 in. 
(6 mm) nominal 

(i) If arc welding, gas welding, or brazing are used for 
the attachment of nozzles, tubes, and fittings, for repair or 
for the closing of peripheral seams, the qualification of 
welding or brazing procedure and welding or brazing per- 
formance shall be conducted in accordance with the 
requirements of Section IX. Filler metals, if used, shall 
conform to the requirements of Section IX. 

(j) For construction having sheets formed within dies 
where the dies control the shape of the pillow and restrain 
the spot welds so that the bending in the sheet is outside 
the heat affected zone, the welding may be done before or 
after forming. The requirements and limitations in (d)(2) 
above do not apply to this method of construction. 



100 



2007 SECTION IV 



ARTICLE 8 
FABRICATION REQUIREMENTS 



HW-800 FORMING PLATES 

The ends of plates that form the longitudinal joints of 
boiler shells shall be formed by pressure, not sledging, to 
the proper curvature. 



HW-801 BASE METAL PREPARATION 

(a) The preparation of joints prior to welding may 
involve any of the conventional methods in use such as 
machining, thermal cutting, chipping, grinding, or combi- 
nations of these. 

(b) Where thermal cutting is used, the effect on the 
mechanical and metallurgical properties of the base metal 
shall be taken into consideration. 

(c) The method of base metal preparation used shall 
leave the welding groove with reasonably smooth surfaces 
and free from deep notches, striations, or irregularities. 
The surfaces for welding shall be free of all scale, rust, 
oil, grease, or other foreign materials. 

(d) Cast surfaces to be welded shall be machined, 
chipped, or ground where necessary to remove foundry 
scale and to expose sound metal. 



HW-810 ASSEMBLY 

(a) Parts that are being welded shall be fitted, aligned, 
and retained in position during the welding operation 
within the tolerance specified in HW-812. 

(b) Bars, jacks, clamps, tack welds, or other appropriate 
means may be used to hold the edges of the parts to be 
welded in alignment. 

(c) Tack welds used to secure alignment shall either be 
removed completely when they have served their purpose, 
or their stopping and starting ends shall be properly pre- 
pared by grinding or other suitable means so that they may 
be satisfactorily incorporated into the final weld. Tack 
welds, whether removed or left in place, shall be made 
using a fillet weld or butt weld procedure qualified in 
accordance with Section IX. Tack welds to be left in place 
shall be made by welders qualified in accordance with 
Section IX and shall be examined visually for defects, and 
if found defective shall be removed. 



It is not necessary that a subcontractor performing such 
tack welds for the vessel manufacturer be a holder of an 
ASME Certificate of Authorization. If the tack welds are 
permanently left in place, the final vessel manufacturer 
shall maintain the controls to assure that the necessary 
welding procedure and performance qualifications are met 
in order to satisfy Code requirements. 

(d) When joining two parts by the inertia and continuous 
drive friction welding processes, one of the two parts must 
be held in a fixed position and the other part rotated. The 
two faces to be joined must be essentially symmetrical 
with respect to the axis of rotation. Some of the basic types 
of applicable joints are solid round to solid round, tube to 
tube, solid round to tube, solid round to plate, and tube 
to plate. 



HW-812 ALIGNMENT TOLERANCE 

(a) The edges of plates at butt joints shall not be offset 
from each other at any point in excess of the amount in 
the following table, where t is the plate thickness. 

Direction of Joints in 
Cylindrical Vessels 



Plate Thickness, in. 

Up to !/ 2 (13 mm), incl. 
Over !/ 2 to \ (13 mm to 

19 mm), incl. 
Over 3 / 4 (19 mm) 



Longitudinal 

'/ 8 in. (3.0 mm) 
% in. (3.0 mm) 



Circumferential 



3 / 1( 5 in. (5.0 mm) 



(b) Butt joints in heads and butt joints between cylindri- 
cal shells and hemispherical heads shall meet the require- 
ments in (a) above for longitudinal joints in cylindrical 
shells. 



HW-813 DISTORTION 

(a) The cylinder or barrel of a drum or shell shall be 
circular at any section within a limit of 1 % of the mean 
diameter, based on the differences between the maximum 
and minimum mean diameters at any section, and if neces- 
sary to meet this requirement shall be reheated, rerolled, 
or reformed. To determine the difference in diameters, 
measurements may be made on the inside or the outside. 



101 



2007 SECTION IV 



For vessels with longitudinal lap joints, the permissible 
difference in inside diameters may be increased by the 
nominal plate thickness. 

(b) Cylindrical furnaces and other cylindrical parts sub- 
jected to external pressure shall be rolled to a circle with 
a maximum permissible deviation from the true circle of 
not more than !/ 4 in. (6 mm). 



HW-820 SPECIFIC WELDING 
REQUIREMENTS 
HW-820.1 Finished Longitudinal and Circumferen- 
tial Joints 

(a) Butt welded joints shall have complete penetration 
and full fusion. The surface of the weld may be left as- 
welded provided the weld is free of coarse ripples, grooves, 
overlaps, abrupt ridges, or valleys. A reduction in thickness 
due to the welding process is acceptable provided all of 
the following conditions are met: 

(1) The reduction in thickness shall not reduce the 
material of the adjoining surfaces below the minimum 
required thickness at any point. 

(2) The reduction in thickness shall not exceed V32 in. 
(0.8 mm) or 10% of the nominal thickness of the adjoining 
surface, whichever is less. 1 

HW-820.2 Fillet Welds. In making fillet welds, the 
weld metal shall be deposited in such a way that adequate 
penetration into the base metal at the root of the weld is 
secured. The reduction of the thickness of the base metal 
due to the welding process at the edges of the fillet weld 
shall meet the same requirements as for butt welds [see 
HW-820.1]. 

HW-820.3 Double-Welded Butt Joints. Before 
applying weld metal on the second side to be welded, the 
root of double- welded butt joints shall be prepared by 
suitable methods such as chipping, grinding, or thermal 
gouging, so as to secure sound metal at the base of weld 
metal deposited on the face side, except for those processes 
of welding by which proper fusion and penetration are 
otherwise obtained and by which the root of the weld 
remains free from impurities. 

HW-820.4 Stud Welding. In the case where arc stud 
welding and resistance stud welding is used to attach load 
carrying studs, a production stud weld test of the procedure 
and welding operator shall be performed on five studs, 
welded and tested in accordance with either the bend or 
torque stud weld testing described in Section DC as follows: 



1 It is not the intent of this paragraph to require measurement of 
reductions in thickness due to the welding process. If a disagreement 
between the Manufacturer and the Inspector exists as to the acceptability 
of any reduction in thickness, the depth shall be verified by actual mea- 
surement. 



(a) prior to start of daily operation if used continuously 
on units of similar construction 

(b) prior to the start of application to a given unit when 
not used continuously 

(c) after adjustment or servicing is done on welding 
equipment 

HW-820.5 Procedure and Performance Qualifica- 
tion Tests and Material Requirements for Stud Weld- 
ing. Procedure and performance qualification tests for stud 
welds shall be made in accordance with Section IX. Further 
requirements for stud welding are as follows. 

(a) Metallic coatings (such as cadmium plating) if used 
shall not be within V 2 in. (13 mm) from the weld end of 
the stud. 

(b) The base metal must be above 50°F (10°C) during 
the welding process. 

HW-820.6 Stud Welding. When stud welding and 
resistance stud welding are used for joining nonpressure- 
bearing attachments, which have essentially no load-car- 
rying function [such as extended heat transfer surfaces and 
insulation attachment pins, except as provided in 
HW-840(b)], to pressure parts by an automatic welding 
process performed in accordance with a Welding Procedure 
Specification (in compliance with Section IX as far as 
applicable), procedure and performance qualification test- 
ing is not required. 

When stud welding is used to attach nonload-carrying 
studs, a production stud weld test, appropriate to the end 
use application requirements, shall be specified by the Man- 
ufacturer or Assembler and carried out on a separate test 
plate or tube 

(a) prior to the start of daily operation if used continu- 
ously on units of similar construction 

(b) prior to the start of application to a given unit when 
not used continuously 

(c) after adjustment or servicing is done on welding 
equipment 

HW-820.7 The welded joint between two members 
joined by the inertia and continuous drive friction welding 
processes shall be a full penetration weld. Visual examina- 
tion of the as-welded flash roll of each weld shall be made 
as an in-process check. The weld upset shall meet the 
specified amount within ±10%. The flash shall be removed 
to sound metal. 

HW-820.8 Welding (Brazing) by Non-Certificate 
Holders 

(a) Welders, including brazers, and welding and brazing 
operators not in the employ of the manufacturer (Certificate 
of Authorization Holders) may be used to fabricate boilers 
or parts thereof constructed in accordance with the Section, 
provided all of the following conditions are met: 



102 



2007 SECTION IV 



(1) All Code construction shall be the responsibility 
of the Manufacturer. 

(2) All welding shall be performed in accordance 
with the Manufacturer's welding procedure specifications 
which have been qualified by the Manufacturer in accor- 
dance with the requirements of Section IX and this Section. 

(3) All welders shall be qualified by the Manufacturer 
in accordance with the requirements of Section IX and this 
Section. 

(4) The Manufacturer's quality control system shall 
include as a minimum the following: 

(a) a requirement for complete and exclusive 
administrative and technical supervision of all welders by 
the Manufacturer 

(b) evidence of the Manufacturer's authority to 
assign and remove welders at his discretion without 
involvement of any other organization 

(c) a requirement for Assignment of Welder Identi- 
fication symbols 

(d) evidence that this program has been accepted 
by the Manufacturer's Authorized Inspection Agency 
which provides the inspection service 

(5) The Manufacturer shall be responsible for Code 
compliance of the completed boiler or part, including Code 
symbol stamping and providing Data Report Forms prop- 
erly executed and countersigned by the Inspector. 

HW-820.9 Flash Welding. If tube butt welds are made 
using the flash welding process, production testing shall 
be performed in accordance with Section IX, QW-199.7.3 
as follows: 

(a) one example shall be tested at the start of production 

(b) one sample shall be tested at the beginning, mid- 
point, and end of each work shift 

(c) when production shifts are consecutive, a test at the 
end of the shift may serve as the test for the beginning of 
the next shift 

(d) when a welding operator is replaced during pro- 
duction 

(e) if any machine's settings are changed 

When any production run weld fails to pass the required 
tests, the welding parameters shall be adjusted until two 
consecutive welds pass the bend test. In addition, all welds 
that were made subsequent to the previous successful test 
shall be either cut out and rewelded or cut out and tested 
in reverse sequence of welding until two successive welds 
pass the tests. 

HW-830 REPAIR OF WELD DEFECTS 

Visible defects, such as cracks, pinholes and incomplete 
fusion, and defects detected by leakage tests shall be 



removed by mechanical means or by thermal grooving 
processes, after which the joint shall be rewelded and reex- 
amined. 



HW-840 POSTHYDROTEST WELDING OF 
NONPRESSURE PARTS TO 
PRESSURE PARTS 

(a) Nonpressure parts, other than insulation attachment 
pins welded by the capacitive discharge method, may be 
welded to pressure parts after the hydrostatic test has been 
performed in accordance with the requirements as set forth 
in HG-510, provided the following criteria are met. 

(1) The welding is done in accordance with this Sub- 
part (see HW-820). 

(2) The material requirements shall comply as 
follows: 

(a) The pressure part material is limited to P-No. 1 , 
Group 1 or 2 materials. 

(b) The nonpressure attachment material is limited 
to carbon steel with a carbon content not exceeding 0.20% 
or any P-No. 1 material. 

(c) When the nonpressure attachment material is 
other than P-No. 1, a minimum 200°F (93°C) preheat shall 
be applied when the pressure part thickness exceeds \ in. 
(19 mm). 

(3) The attachment is done by stud welding or with 
fillet welds where the throat of the weld is not to exceed 
the lesser of 1.5 times the thickness of the pressure part 
or V 4 in. (6 mm). 

(4) The completed weld is inspected by the Author- 
ized Inspector. 

(5) The Manufacturer's Data Report Form shall be 
signed only after completion of the welding. 

(6) Welding is not permitted on brazed joints. 

(b) Insulation attachment pins may be stud welded to 
pressure parts after the hydrostatic test without requiring 
inspection by the Authorized Inspector and without requir- 
ing a production stud weld test, provided the following 
conditions are met. 

(1) Insulation attachment pins shall have a nominal 
diameter not exceeding 50% of the plate thickness or 3 / 16 in. 
(5.0 mm), whichever is less. 

(2) Capacitive discharge welding process shall be 
used. 

(3) The procedure shall be included in the Manufac- 
turer's Quality Control Manual, and the Authorized Inspec- 
tor shall have the opportunity to monitor the process. 

(4) The insulation attachment pins shall be installed 
prior to application of the Code Symbol Stamp and the 
signing of the Manufacturer's Data Report. 



103 



2007 SECTION IV 



ARTICLE 9 
INSPECTION 



HW-900 INSPECTION DURING 
FABRICATION 

The manufacturer shall submit the boiler or other pres- 
sure part for inspection at such stages of the work as may 
be designated by the Inspector. 



HW-910 CHECK OF WELDING PROCEDURE 
QUALIFICATIONS 

(a) It is the duty of the Inspector to assure himself 
that the welding procedures employed in construction have 
been qualified under the provisions of Section IX. The 
manufacturer shall submit evidence to the Inspector that 
those requirements have been met. 

(b) The Inspector has the right at any time to call for 
and witness the test welding and testing, although it is not 



mandatory that he witness the test welding and the testing 
unless he so desires. 

HW-911 CHECK OF WELDER AND WELDING 
OPERATOR PERFORMANCE 
QUALD7ICATIONS 

(a) It is the duty of the Inspector to assure himself 
that all welding is done by welders or welding operators 
qualified under the provisions of Section IX. The manufac- 
turer shall make available to the Inspector a certified copy 
of the record of performance qualification tests of each 
welder and welding operator as evidence that these require- 
ments have been met. 

(b) The Inspector has the right at any time to call for 
and witness the test welding and testing, although it is not 
mandatory that he witness the test welding and the testing 
unless he so desires. 



104 



2007 SECTION IV 



PART HF — SUBPART HB 

REQUIREMENTS FOR BOILERS 

FABRICATED BY BRAZING 



ARTICLE 10 
GENERAL REQUIREMENTS 



HB-1000 SCOPE 

The requirements of this Subpart HB are applicable to 
boilers and parts thereof that are fabricated by brazing. 



HB-1001 RESPONSIBILITY OF 
MANUFACTURER OR 
CONTRACTOR 

Each manufacturer or contractor is responsible for the 
brazing done by his organization and shall establish the 



procedures and conduct the tests required in Section IX to 
qualify the brazing procedures he uses in the construction 
of the brazed assemblies built under Section IV and the 
performance tests of brazers and brazing operators to deter- 
mine their ability to apply the procedure properly. 



105 



2007 SECTION IV 



ARTICLE 11 
MATERIAL REQUIREMENTS 



HB-1100 GENERAL 

Materials used in the construction of boilers and parts 
thereof by brazing shall conform to the specifications in 
Section n, and shall be limited to those materials for which 
allowable stress values have been assigned in 
Table HF-300.1 and Table HF-300.2. The materials being 
brazed shall be of proved brazing quality with the brazing 
filler metal employed. Satisfactory qualification of the braz- 
ing procedure under Section IX is considered proof of 
acceptable material for brazed construction. 



HB-1102 BRAZING FILLER METALS 

The selection of the brazing filler metal for a specific 
application shall depend upon its suitability for the base 
metals being joined. Satisfactory qualification of the braz- 
ing procedure under Section IX is considered proof of the 
suitability of the filler metal. Brazing used with brazing 
filler metals other than those listed in Section II, Part C, 
SFA-5.8 shall be separately qualified for both procedure 
and performance qualification in accordance with Sec- 
tion IX. 



HB-1101 COMBINATIONS OF DISSIMILAR 
MATERIALS 

Combinations of dissimilar metals may be joined by 
brazing provided they meet the qualification requirements 
of Section IX. 



HB-1103 FLUXES AND ATMOSPHERES 

Suitable fluxes or atmospheres or combinations of fluxes 
and atmospheres shall be used to prevent oxidation of the 
brazing filler metal and the surfaces to be joined. Satisfac- 
tory qualification of the brazing procedure under Section 
IX is considered proof of the suitability of the flux and /or 
atmosphere. 



106 



2007 SECTION IV 



ARTICLE 12 

BRAZING PROCESSES, PROCEDURES, 

AND QUALIFICATIONS 



HB-1200 BRAZING PROCESSES 

Specific brazing processes which are permitted for use 
under this Section are classified by method of heating 
and are torch brazing, furnace brazing, induction brazing, 
electrical resistance brazing, and dip brazing — salt and 
flux bath. 



HB-1201 JOINT BRAZING PROCEDURES 

A joint brazing procedure shall be developed for each 
different type of joint of a brazed assembly. A recom- 
mended form for recording the brazing procedure is shown 
in QB-480 of Section IX. If more than one joint occurs in 
a brazed assembly, the brazing sequence shall be specified 
on the drawing or in instructions accompanying the draw- 
ing. If welding and brazing are to be done on the same 
assembly, the welding shall precede the brazing unless it 
is determined that the heat of welding will not adversely 
affect the braze previously made, and the weld will not be 
adversely contaminated by the brazing metal. 



HB-1202 BRAZING QUALIFICATIONS AND 
RECORDS 
HB-1202.1 Qualification of Brazing Procedures 

(a) Each brazing procedure employed in the fabrication 
of boilers shall be qualified in accordance with Section IX. 
Only qualified procedure specifications shall be followed in 
construction. Each manufacturer shall conduct the required 
tests to qualify all brazing procedures to be used by his 
organization. 



(b) The nominal thickness of base material used with 
lap joints tested using the test fixture shown in QB-463.7 
of Section IX shall not exceed V 2 in. (13 mm). There is 
no thickness limitation when specimens are tested without 
the test fixture shown in QB-463.7. 

HB-1202. 2 Qualification of Brazers and Brazing 
Operators. All brazers assigned to manual brazing shall 
have passed the tests prescribed for brazers in Section IX. 
All brazing operators assigned to brazing by automatic 
means or by furnace, induction, resistance, or dip brazing 
shall pass the tests as prescribed in Section IX. Such tests 
shall be conducted by the manufacturer or contractor. 

HB-1202.3 No Production Work Without Qualifica- 
tions. No production work shall be undertaken until both 
the brazing procedure and the brazers or brazing operators 
have been qualified. 

HB- 1202.4 Maintenance of Records of Qualifications 
and Identifying Marks 

(a) The manufacturer shall maintain qualification rec- 
ords of the brazers and brazing operators employed by him 
showing the date and results of qualifying tests and the 
identifying mark assigned to each. These records shall be 
certified to by the Manufacturer by signature or some other 
method of control in accordance with the Manufacturer's 
quality control system, and shall be accessible to the 
Inspector. 

(b) Each brazer and brazing operator so qualified shall 
be assigned an identifying number, letter, or symbol by 
the manufacturer which shall be used to identify the work 
of that brazer or brazing operator. 



107 



2007 SECTION IV 



ARTICLE 13 
DESIGN 



HB-1300 STRENGTH OF BRAZED JOINTS 

(a) It is the responsibility of the designer to determine 
from suitable tests or from past experience that the specific 
brazing filler metal selected can produce a joint which 
will have adequate strength over the operating temperature 
range. The strength of the brazed joint shall not be less 
than the strength of the base metal, or the weaker of the 
two base metals in the case of dissimilar metal joints. 

(b) For any type of joint, the strength of the brazed 
section shall exceed that of the base metal portion of the 
test specimen in the qualification tension tests provided for 
in QB-150 of Section IX. Lap joints shall have a sufficient 
overlap to provide a higher strength in the brazed joint 
than in the base metal. 



HB-1301 BRAZED JOINT EFFICIENCY 
FACTORS 

(a) The joint efficiency factor to be used in design of 
boilers with brazed joints shall be 0.80 for joints in which 
visual examination assures that the brazing filler metal has 
penetrated the entire joint. 

(b) The joint efficiency factor to be used in the design 
of boilers shall be 0.50 for joints in which visual examina- 
tion will not provide proof that the brazing filler metal has 
penetrated the entire joint. 



HB-1302 MINIMUM THICKNESS 

The minimum thickness of nonferrous and other copper 
or copper-alloy plates, heads, and tubesheets shall be as 
specified in HF-301. 



HB-1303 PERMISSIBLE SERVICE 
TEMPERATURE 

Satisfactory qualification of the brazing procedure in 
accordance with Section IX, Part QB is considered satisfac- 
tory proof of the adequacy of the base materials, the brazing 
filler metal, the flux and /or atmosphere, and other variables 
of the procedure for service not exceeding 250°F (120°C). 



HB-1304 APPLICATION OF BRAZING FILLER 
METAL 

The design shall provide for the application of the braz- 
ing filler metal as part of the design of the joint. Where 
practicable, the brazing filler metal shall be applied in such 
a manner that it will flow into the joint or be distributed 
across the joint and produce visible evidence that it has 
penetrated the joint. 

(a) Manual Application. The manual application of the 
brazing filler metal by face-feeding to a joint should be 
from one side only. Visual observation of the other side 
of the joint will then show if the required penetration of 
the joint by the filler metal has been obtained. If the side 
opposite to the filler metal application cannot be visually 
examined, as is the case with socket-type joints in pipe 
and tubing (blind joint), a joint efficiency factor of 0.50 
shall be used in design of this joint. 

(b) Preplaced Brazing Filler Metal. The brazing filler 
metal may be preplaced in the form of slugs, powder, rings, 
strip, cladding, spraying, or other means. After brazing, 
the brazing filler metal should be visible on both sides of 
the joint. If the brazing filler metal is preplaced within a 
blind joint in such a manner that it penetrates the major 
portion of the joint during brazing and appears at the visible 
side of the joint, a joint efficiency factor of 0.80 may be 
used in the design of the joint. If the brazing filler metal 
is preplaced on the outside or near the outside of a blind 
joint, and the other side cannot be inspected to ascertain 
complete penetration, then a joint efficiency factor of 0.50 
shall be used in the design of the joint. 



HB-1305 JOINT CLEARANCE 

(a) The joint clearance shall be kept sufficiently small 
so that the filler metal will be distributed by capillary 
attraction. Since the strength of a brazed joint tends to 
decrease as the joint clearance used is increased, the clear- 
ances for the assembly of joints in boilers shall be within 
the tolerances set up by the joint design and as used for the 
corresponding qualification specimens made in accordance 
with Section IX. 



108 



2007 SECTION IV 



(b) If greater tolerances are to be used in production, 
the joint must be requalified for those greater tolerances. 
The control of tolerances required may be obtained by 
using rivets, spot welding, crimping, or other means which 
will not interfere with the quality of the braze. If such means 
are employed in production, they must also be employed in 
qualification of procedure, brazer, and operator. 

NOTE: For guidance, see Table HB-1305, which gives recommended 
joint clearances at brazing temperature for various types of brazing filler 
metal. Brazing alloys will exhibit maximum unit strength if clearances 
are maintained within these limits. 



TABLE HB-1305 

RECOMMENDED JOINT CLEARANCES AT 

BRAZING TEMPERATURE 



Brazing Filler 




Metal 


Clearance, in. (mm) 


B Al Si Group 


0.006-0.010 (0.15-0.25) for laps 




< V 4 in. (6.35) 




0.010-0.025 (0.25-0.64) for 




laps > \ in. (6.35) 


B CuP Group 


0.001-0.005 (0.02-0.12) 


B Ag Group 


0.002-0.005 (0.05-0.12) 


B Cu Zn Group 


0.002-0.005 (0.05-0.12) 


B Cu Group 


0.000-0.002 (0.00-0.05) 



HB-1306 OPENINGS 



(a) Openings for nozzles and other connections shall 
be far enough away from any main brazed joint so that 
the joint and the opening reinforcement plates do not inter- 
fere with one another. 

(b) Openings for pipe connections in boilers having 
brazed joints may be made by inserting pipe couplings, 
not exceeding NPS 3 (DN 80), or similar devices in the 
shell or heads and securing them by welding, provided the 
welding is performed by welders who have been qualified 
under the provisions of Section IX for the welding position 
and type of joint used. Such attachments shall conform to 
the rules for welded connections. 



HB-1307 BRAZED CONNECTIONS 

(a) Connections, such as saddle type fittings and fittings 
inserted into openings formed by outward flanging of the 
vessel wall, in sizes not exceeding NPS 3 (DN 80), may 
be attached to boilers by lap joints of brazed construction. 
Sufficient brazing shall be provided on either side of the 
line through the center of the opening parallel to the longi- 
tudinal axis of the shell to develop the strength of the 
reinforcement through shear in the brazing. 

(b) For nozzle fittings having a bolting flange and an 
integral flange for brazing, the thickness of the flange 
attached to the boiler shall not be less than the thickness 
of the neck of the fitting. 



109 



2007 SECTION IV 



ARTICLE 14 
FABRICATION REQUIREMENTS 



HB-1400 CLEANING OF SURFACES TO BE 
BRAZED 

The surfaces to be brazed shall be clean and free from 
grease, paint, oxides, scale, and foreign matter of any kind. 
Any chemical or mechanical cleaning method may be used 
that will provide a surface suitable for brazing. 



HB-1401 POSTBRAZING OPERATIONS 

Brazed joints shall be thoroughly cleaned of flux residue 
by any suitable means after brazing and prior to inspection. 1 
Other postbrazing operations such as thermal treatments 



1 Flux residues can be extremely corrosive as well as interfere with 
visual inspection. 



shall be performed in accordance with the qualified pro- 
cedure. 



HB-1402 REPAIR OF DEFECTIVE BRAZING 

Brazed joints which have been found to be defective 
may be rebrazed, where feasible, after thorough cleaning, 
and by employing the same brazing procedure used for the 
original braze. If a different brazing procedure is employed 
i.e., torch repair of furnace brazed parts, a repair brazing 
procedure shall be established and qualified. 

When a repair brazing procedure is established it shall 
provide control of the application of brazing filler metal 
to meet the conditions set forth in HB-1301(a). Where 
these requirements cannot be met, the limitations of 
HB-1301(b) will apply. 



110 



2007 SECTION IV 



ARTICLE 15 
INSPECTION AND STAMPING 



HB-1500 INSPECTION 
HB-1501 INSPECTION OF BRAZING 
PROCEDURE 

The Inspector shall examine the procedure for each type 
of joint being produced and shall determine that the proce- 
dure has been qualified in accordance with the requirements 
of Section IX and shall satisfy himself that fabrication of 
the joint is in accordance with the procedure. Where there 
is evidence of consistent poor quality, the Inspector shall 
have the right at any time to call for and witness tests of 
the brazing procedure. 

HB-1502 CERTIFICATION OF BRAZER AND 
BRAZING OPERATOR 

(a) The manufacturer shall certify that the brazing on 
a vessel or part thereof has been done by brazers or brazing 
operators who are qualified under the requirements of Sec- 
tion IX, and the Inspector shall assure himself that only 
qualified brazers or brazing operators have been used. 

(b) The manufacturer shall make available to the Inspec- 
tor a certified copy of the record of the qualification tests 
of each brazer and brazing operator. The Inspector shall 
have the right at any time to call for and witness tests of 
the ability of a brazer or brazing operator. 

HB-1503 VISUAL EXAMINATION 

(a) Where possible, both sides of each brazed joint shall 
be visually examined after flux residue removal. Where it 



is not possible to inspect one side of a brazed joint (blind 
joint), the Inspector shall check the design to determine 
that the proper joint factor has been employed, unless he 
can assure himself that the brazing filler metal has been 
preplaced in such a manner that it satisfied HB-1304. 

(b) There shall be evidence that the brazing filler metal 
has penetrated the joint. In a butt braze there shall be no 
concavity. The braze may be repaired or rebrazed. 

(c) The presence of a crack in the brazing filler metal 
shall be cause for rejection. Dye penetrant inspection may 
be used if desired. The braze may be repaired or rebrazed. 

( d) The presence of a crack in the base metal adjacent 
to a braze shall be cause for rejection even if the crack 
is filled with brazing alloy. Such cracking shall not be 
repaired. 

(e) Visible pinholes or open defects in the braze shall 
be cause for rejection. The joint may be rebrazed. 

(f) Rough fillets, particularly those with a convex 
appearance, are cause for rejection. Such joints may be 
repaired or rebrazed. 



HB-1510 STAMPING 

Boilers shall be stamped according to the requirements 
of HG-530 or the stamping may be placed on a nonferrous 
plate, irremovably attached to a visible part of the boiler. 



Ill 



2007 SECTION IV 



PART HC 
REQUIREMENTS FOR BOILERS 
CONSTRUCTED OF CAST IRON 



ARTICLE 1 
GENERAL 



07 HC-100 SCOPE 

The rules in Part HC are applicable to heating boilers that are constructed primarily of cast iron sections, and shall 
be used in conjunction with general requirements of Part HG of this Section. 



112 



2007 SECTION IV 



ARTICLE 2 
MATERIAL REQUIREMENTS 



HC-200 GENERAL MATERIAL 
REQUIREMENTS 

(a) All materials used for cast sections of boilers that 
are constructed primarily of cast iron shall meet the require- 
ments of this Article for gray iron castings. 

(b) External appurtenances, such as cast or welded head- 
ers and other miscellaneous pressure parts, shall be manu- 
factured under part HC or HF-203. The design pressure 
for these pressure parts for which the strength cannot be 
computed shall be established in accordance with HG-500. 

HC-201 MANUFACTURE 

The melting procedure shall be optional with the Manu- 
facturer. 

HC-202 CHEMICAL COMPOSITION 

Drillings taken from test ingots, broken test specimens, 
or from castings, shall conform to the following as to 
chemical composition. 

(a) The manganese shall be controlled as required to 
meet Mn > (1 .7 x S) + 0.2, where Mn is percent manganese 
and S is percent sulfur. 

(b) The phosphorous content shall not exceed 1.00%. 



transverse tests shall determine compliance for the various 
classes given in HC-203. (See HC-212, Retests.) 



HC-205 TEST BARS 

Test bars shall be cast separately from the castings (see 
HC-207). The sizes of cast test bars shall be as determined 
in HC-206. Tension specimens shall be machined from 
those castings to the dimensions shown in Fig. HC-205. 1. 
Tension test specimens "cast to size" shall not be used. 
The test bar castings shown in Fig. HC-206. 1 may be used 
for optional transverse tests, when that test is specified. 



HC-206 SELECTION OF TEST BAR SIZE 

The dimensions of the test bars as shown in 
Fig. HC-206. 1 shall be determined by the thickness of the 
controlling section of the casting as follows (the body or 
shell of the casting shall be the controlling section): 



Thickness of Controlling 

Section of Casting, 

in. (mm) 

0.5 (13) and under 
0.51 to 1.00 (13.0 to 25) 
over 1.00 (25) 



Test Bar 

A 
B 
C 



HC-203 TENSILE STRENGTH 
CLASSIFICATION 

Castings shall be known and listed by classes according 
to the minimum requirements as to tensile strengths of test 
bars, specified as follows: 

Class No. Tensile Strength Min., psi (MPa) 



20 


20,000 (140) 


25 


25,000 (170) 


30 


30,000 (200) 


35 


35,000 (240) 


40 


40,000 (275) 


4 


TENSION TEST 



HC-204 

The tension test shall be considered the primary test for 
qualification under this Article. The results of the tension or 



HC-207 MOLDING AND POURING TEST 
BARS 

Test bars shall be made under the same sand conditions 
as the castings. The bars shall be poured from the same 
ladles of iron used to pour the castings. The test bars shall 
receive the same thermal treatment as the castings. Thermal 
treatment involving a liquid quench from above the critical 
range is not permitted for castings covered in this Article. 



HC-208 TENSILE STRENGTH TEST 
PROCEDURE 

Tension test specimens (Fig. HC-205. 1) shall fit the 
holders of the testing machine in such a way that the 
load shall be axial. The use of self-aligning shackles is 



113 



2007 SECTION IV 



FIG. HC-205.1 DIMENSIONS OF TENSILE TEST SPECIMEN 
L 




Dimensions 







Tension Test Specimen, 


A 


Tension test Specimen, 


B 


Tension Test Specimen, C 


G- 

D- 
R- 


Length of parallel, min., 
in. (mm) 

Diameter, in. (mm) 
Radius of fillet, min., in. 


0.50 (13) 

C0.500 ± 0.010 (13 ± 0.25)] 
1 (25) 


0.75 (19) 

[0.750 ± 0.015 (19 ± 
1 (25) 


D.38)] 


1.25 (32) 

[1.25 ± 0.025 (32 ± 0.63)] 
2 (51) 


A - 
L - 


Length of reduced section, 

min., in. (mm) 

Overall Length, min., in. 


lV 4 (32) 
3 3 / 4 (95) 






lV 2 (38) 
4 (100) 






2V 4 (57) 
6 3 / 8 (160) 


C- 
E- 
F- 


Diameter of end section, 
in. (mm), approximately 
Length of shoulder, min., 
in. (mm) 
Diameter of shoulder, in. 


% (19) 

V 4 (6) 

[ 5 / 8 ± V 64 (16 ± 


0.4)] 




lV 8 (29) 
V 4 (6) 
C 15 /i6 ± V M 


(24 ± 0.4)] 




l 7 / 8 (48) 

5 /ie (8) 

[1 7 / 16 ± V 64 (37 ± 0.4)] 


B- 


Length of end section 


Note (1) 






Note (1) 






Note (1) 



NOTE: 

(1) Optional to fit holders on testing machine. If threaded, root diameter shall not be less than dimension F. 



recommended. 1 After reaching a stress equivalent to 
15,000 psi (100 MPa), the speed of the moving head of 
the testing machine shall not exceed 0.125 in. /min 
(3.18 mm/min). 



HC-209 TRANSVERSE TEST 

(a) Except for the tensile tests required in HC-402.2, 
the Manufacturer may waive the tension test and the trans- 
verse test may be used. When used, the minimum breaking 
load, lb, prescribed as follows, shall apply (see HC-212 
Retests): 



The use of ball and socket holders in the tensile strength test is 
recommended. Tests made under conditions where eccentric loadings 
may occur will give erroneous results. 





Test Bar A 


Test Bar B 


Test Bar C 




0.875 in. 


1.20 in. (30 mm) 


2.00 in. (50 mm) 




(22 mm) Diam., 


Diam., 


Diam., 


Class 


12 in. (300 mm) 


18 in. (450 mm) 


24 in. (600 mm) 


No. 


Supports, lb (kg) 


Supports, lb (kg) 


Supports, lb (kg) 


20 


900 (400) 


1,800 (800) 


6,000 (2 700) 


25 


1,025 (450) 


2,000 (900) 


6,800 (3 000) 


30 


1,150 (500) 


2,200 (1 000) 


7,600 (3 400) 


35 


1,275 (550) 


2,400 (1 100) 


8,300 (3 700) 


40 


1,400 (600) 


2,600 (1 200) 


9,100 (4 100) 



(b) Where the transverse test has been made as pre- 
scribed in (a) above and the transverse or flexure test bar 
fails to meet the load requirements, the Manufacturer shall 
have the right to have a tension test specimen machined 
from a broken end of the transverse test bar tested. In 
the event that this tension test specimen conforms to the 
requirements of the class specified, as prescribed in 



114 



2007 SECTION IV 



FIG. HC-206.1 CAST TEST BARS 













1 










-- fiX e 








\ir* 








\ 








■ D ' 






Test Bar 


Diameter a, 
in. (mm) 


Dimensions Length, b, 
in. (mm) [Note (1)] 


Distance Between Supports 

in Transverse Test, 

in. (mm) 


Permissible Variations, 
in. (mm) 


A 
B 
C 


0.875 (22) 
1.20 (30) 
2.00 (50) 


15 (380) 
21 (530) 
27 (680) 


12 (300) 
18 (460) 
24 (600) 


±0.05 (±1.3) 
±0.10 (±2.5) 
±0.10 (±2.5) 



GENERAL NOTE: Test bars shall be plain, cylindrical shapes as shown. Where bars are cast on end, allowance for draft may be made. However, 
the diameter at the center of the length must correspond to the normal diameter, within the permissible variations. 

NOTE: 

(1) If only tensile strength are specified, dimensions b may be reduced to the minimum length shown in Fig. HC-205.1. 



HC-203, the class requirements shall be considered as hav- 
ing been met, irrespective of the transverse breaking load. 

HC-210 TRANSVERSE TEST PROCEDURE 

(a) The transverse test shall be made on the bar as cast, 
or as skin machined (provided in the latter case that the 
diameter is not reduced below the minimum sizes given 
in Table HC-210) with central loading between supports. 
Corrections shall be made for sizes of round bars as shown 
in Table HC-210. In case of slightly elliptical bars (maxi- 
mum and minimum diameters both within the tolerances 
given in Table HC-210), loading shall be on the minimum 
diameter, and the correction factor shall be obtained as 
follows: Square the depth of the bar measured at the point 
of application of the original load, multiply by the width, 
and divide the product by the cube of the diameter of 
the standard or nominal size bar. A bar whose diameters 
(maximum and minimum) vary by more than 0.025 in. 
(0.60 mm) for the 0.875 in. (22 mm) diameter nominal 
size, or by more than 0.050 in. (1.25 mm) for the 1.2 in. 
(30 mm) and 2.0 in. (50 mm) diameter nominal sizes, 
respectively, shall be considered a slightly elliptical bar. 

(b) In all cases, controlling dimensions shall be the 
diameter of the bar at fracture. 

( c) The rate of application of the load shall be such that 
fracture is produced in not less than 15 sec for the 0.875 
in. (22 mm) diameter bar, 20 sec for the 1.2 in. (30 mm) 
diameter bar, and 40 sec for the 2.0 in. (50 mm) diame- 
ter bar. 



HC-211 NUMBER OF TESTS 

(a) For purposes of this requirement, a melting period 
shall not exceed 8 hr. 

(b) For tensile or transverse tests for each class of iron, 
two or more test bars shall be cast from each melt, one 
during the first half of the melting period, and the other 
during the last half of the melting period. For chemical 
composition test samples, see HC-202. 

(c) One chemical composition test and either one tensile 
or one transverse test shall be made on each melt (or 
mixture if two or more mixtures of a different class of iron 
are made in a given melt) for each controlling section (see 
HC-206) in the castings made from each melt (or mixture). 2 



HC-212 



RETESTS 



(a) If any test specimen shows defective machining or 
obvious lack of continuity of metal, it shall be discarded 
and replaced by another specimen. 

(b) In case of the failure of a test bar to meet the specified 
strength within 90% of its value, a retest may be made. If 
the retest fails, the casting shall be rejected, except as 
provided for in (c) below. 



2 Example: If Class 20, Test Bar A, castings alone are being made, 
one test shall be made on each melt on Test Bar A. If Class 20, controlling 
sections A and B castings (that is, light and medium sections) are made 
from the same melt (or mixture), then Test Bars A and B shall be made 
and tested. In all cases, test bars corresponding to the different tensile 
classes (Nos. 20, 30, and 40) and controlling sections (A, B, and C) must 
be made and tested to correspond to the classes of iron specified for the 
castings, and the controlling sections thereof. 



115 



2007 SECTION IV 



TABLE HC-210 

CORRECTION FACTORS FOR TRANSVERSE TEST BARS 

(In order to Correct to the Standard Diameter, the Breaking Load and 

Deflection Obtained in Testing the Bar Shall be Divided by the Respective Correction Factors.) 





Test Bar A 






Test Bar B 






Test Bar C 




0.875 in. 


(22 mm) in 


Diameter 


1.20 in. 


(30 mm) in 


Diameter 


2.000 in. 


(50 mm) in Diameter 


Diameter of 


Correction Factor 


Diameter of 


Correction Factor 




Correction Factor 


Test Bars, 






Test Bars, 






Diameter of Test 




in. (mm) 


Load 


Deflection 


in. (mm) 


Load 


Deflection 


Bars, in. (mm) 


Load 


Deflection 


0.825 (20.96) 


0.838 


1.061 


1.10 (27.94) 


0.770 


1.091 


1.90 (48.26) 


0.857 


1.053 


0.830 (21.08) 


0.853 


1.054 


1.11 (28.19) 


0.791 


1.081 


1.91 (48.51) 


0.871 


1.047 


0.835 (21.21) 


0.869 


1.048 


1.12 (28.45) 


0.813 


1.071 


1.92 (48.77) 


0.885 


1.042 


0.840 (21.34) 


0.885 


1.042 


1.13 (28.70) 


0.835 


1.062 


1.93 (49.02) 


0.899 


1.037 


0.845 (21.46) 


0.900 


1.036 


1.14 (28.96) 


0.857 


1.053 


1.94 (49.28) 


0.913 


1.032 


0.850 (21.59) 


0.916 


1.029 


1.15 (29.21) 


0.880 


1.043 


1.95 (49.53) 


0.927 


1.026 


0.855 (21.72) 


0.933 


1.023 


1.16 (29.46) 


0.903 


1.034 


1.96 (49.78) 


0.941 


1.021 


0.860 (21.84) 


0.949 


1.017 


1.17 (29.27) 


0.927 


1.026 


1.97 (50.04) 


0.955 


1.015 


0.865 (21.97) 


0.966 


1.012 


1.18 (29.97) 


0.951 


1.017 


1.98 (50.29) 


0.970 


1.010 


0.870 (21.10) 


0.983 


1.006 


1.19 (30.23) 


0.975 


1.009 


1.99 (50.55) 


0.985 


1.005 


0.875 (22.23) 


1.000 


1.000 


1.20 (30.48) 


1.000 


1.000 


2.00 (50.80) 


1.000 


1.000 


0.880 (22.35) 


1.017 


0.994 


1.21 (30.73) 


1.025 


0.992 


2.01 (51.05) 


1.015 


0.995 


0.885 (22.48) 


1.034 


0.989 


1.22 (30.99) 


1.051 


0.984 


2.02 (51.31) 


1.030 


0.990 


0.890 (22.61) 


1.051 


0.983 


1.23 (31.24) 


1.077 


0.976 


2.03 (51.56) 


1.046 


0.985 


0.895 (22.73) 


1.069 


0.978 


1.24 (31.50) 


1.105 


0.968 


2.04 (51.82) 


1.061 


0.980 


0.900 (22.86) 


1.087 


0.972 


1.25 (31.75) 


1.130 


0.960 


2.05 (52.07) 


1.076 


0.976 


0.905 (22.99) 


1.106 


0.967 


1.26 (32.00) 


1.158 


0.952 


2.06 (52.32) 


1.092 


0.972 


0.910 (23.11) 


1.125 


0.962 


1.27 (32.26) 


1.185 


0.945 


2.07 (52.58) 


1.109 


0.967 


0.915 (23.24) 


1.143 


0.956 


1.28 (32.51) 


1.214 


0.938 


2.08 (52.83) 


1.125 


0.962 


0.920 (23.37) 


1.162 


0.951 


1.29 (32.77) 


1.242 


0.930 


2.09 (53.09) 


1.141 


0.957 


0.925 (23.50) 


1.181 


0.946 


1.30 (33.02) 


1.271 


0.923 


2.10 (53.34) 


1.158 


0.952 



(c) As provided for in HC-209(b) when the transverse 
test bars fail to meet the specification requirements, tension 
test specimens may be machined from the broken ends of 
the transverse test bar. If the tension specimens meet the 
requirements of the specified class, the castings shall be 
accepted. 



leak may be plugged with a solid cast iron tapered thread 
pipe plug. The maximum size of the pipe plug shall be 
1 in. NPS (DN 25) and there shall be no less than four 
full standard pipe threads in the section metal. (See 
Table HC-213.) 



HC-213 WORKMANSHIP, FINISH, AND 
REPAIR 

(a) The surface of the casting shall conform substan- 
tially to the dimensions on drawings or to the dimensions 
predicated by the pattern, and be free from injurious 
defects. The surface of the casting shall be free from burnt- 
on sand and shall be reasonably smooth. Risers, fins, and 
projections used to facilitate the making of the casting 
shall be removed. In other respects, they shall conform 
to whatever requirements may be specially agreed upon 
between the Manufacturer and Purchaser. 

(b) Seepage about chaplets, and minor leakage defects, 
may be repaired by peening or by plugging as directed 
below. Provided the surrounding metal is sound, a minor 



HC-214 EXAMINATIONS AND TESTS 

The Manufacturer shall be responsible for all examina- 
tions and tests. When requested by a Purchaser, the Manu- 
facturer shall agree to permit a representative of the 
Purchaser to have entry, at the time while work under the 
contract of the Purchaser is being performed, to all parts 
of the Manufacturer's works that concern the castings man- 
ufactured to the requirements of this Article. All examina- 
tions and tests shall be made at the place of the manufacture 
prior to shipment, unless otherwise specified and shall be 
so conducted as not to interfere unnecessarily with the 
operation of the works. 



116 



2007 SECTION IV 



HC-215 TEST RECORDS TABLE HC-213 

PIPE PLUG SIZE FOR MINIMUM WALL THICKNESS 
The Manufacturer shall record and retain all test results 



required by this Article for a period of at least 1 year. The Pi P e Plug ' NPS Minimum Wa " Thick "ess for 4 
. . ,. , n , ,., . , ..- U1 . , 4 , . (DN) Thread Engagement, in. (mm) 
test results shall be readily identifiable with the casting L-i ' 



represented by the test results. V 8 (-) 0.15 (3.8) 

\ (-) 0.22 (5.6) 

% (10) 0.22 (5.6) 

V 2 (15) 0.285 (7.2) 

% (20) 0.285 (7.2) 

1 (25) 0.35 (8.9) 



117 



2007 SECTION IV 



ARTICLE 3 
DESIGN 



HC-300 MAXIMUM ALLOWABLE STRESS 
VALUES 

(a) Table HC-300 gives the maximum allowable stress 
values in tension for castings conforming to the class iron 
listed therein. 

(b) The maximum allowable stress value in bending 
shall be 1 l / 2 times that permitted in tension and the maxi- 
mum allowable stress value in compression shall be two 
times that permitted in tension. 

(c) Stress values in Table HC-300 shall be used in calcu- 
lations employing the available formulas in Part HG when 
applicable to the geometry of the boiler or boiler parts. 
Where the design pressure cannot be calculated under the 
available formulas, then the design pressure of the part 
in question shall be established in accordance with the 
provisions of HC-400. 



HC-301 BASIS FOR ESTABLISHING STRESS 
VALUES IN TABLE HC-300 

In the determination of allowable stress values for pres- 
sure parts, the Committee is guided by successful experi- 
ence in service, insofar as evidence of satisfactory 
performance is available. Such evidence is considered 
equivalent to test data where operating conditions are 
known with reasonable certainty. In the evaluation of new 
materials, it is necessary to be guided to a certain extent 
by the comparison of test information with similar data on 
successful applications of similar materials. 

At any temperature below the creep range, the allowable 
stresses are established at no higher than the lowest of the 
following: 

(1) % of the specified minimum tensile strength at 
room temperature 

(2) V 5 of the tensile strength at temperature 



HC-310 HEADS 
HC-310.1 Heads With Pressure on Concave Side. 

Heads with pressure on the concave side (plus heads) shall 
be designed in accordance with formulas in HG-305 using 
the maximum allowable stress value in tension from 



TABLE HC-300 

MAXIMUM ALLOWABLE STRESS VALUES 

IN TENSION FOR CAST IRON, ksi (MPa) 

(Multiply ksi by 1000 to Obtain psi) 







Minimum 


Maximum Allowable 






Tensile 


Design Stress Values 


Spec. No. 




Strength, 


in Tension, 


[Note (1)] 


Class 


ksi (MPa) 


ksi (MPa) 




20 


20.0 (140) 


4.0 (28) 




25 


25.0 (173) 


5.0 (35) 




30 


30.0 (207) 


6.0 (41) 




35 


35.0 (242) 


7.0 (48) 




40 


40.0 (276) 


8.0 (55) 



GENERAL NOTE: Multiply MPa by 1000 to obtain kPa. 

NOTE: 

(1) Cast iron specifications shall comply with Article 2 of Part HC. 

Table HC-300. Bolted flanges when cast integral with con- 
cave heads shall have dimensions that conform to ANSI 
B16.1, Cast Iron Pipe Flanges and Flanged Fittings, Class 
125 and Class 250, and may be used as part of a pressure 
vessel for pressures not exceeding the ANSI ratings at 
temperatures not exceeding 450°F (230°C). 

HC-310.2 Heads With Pressure on Convex Side. The 

thickness of heads with pressure on the convex side (minus 
heads) shall not be less than the thickness required in 
HC-310.1 for plus heads under the same pressure, nor less 
than 0.01 times the inside diameter of the head skirt. 



HC-311 SPHERICALLY SHAPED COVERS 

Circular cast iron spherically shaped covers with bolting 
flanges, similar to Fig. HC-3 1 1 , sketches (a), (b), and (c), 
shall be designed in accordance with the following, and 
shall also be subjected to the proof test provisions of 
HC-400. 

(a) Notations. The symbols used in the formulas of this 
paragraph are defined as follows: 

A = outside diameter of flange 

B = inside diameter of flange 

C = bolt circle diameter 

L = inside spherical or crown radius 



118 



2007 SECTION IV 



FIG. HC-311 SPHERICALLY SHAPED COVERS WITH BOLTING FLANGES 

Use radius in 
accordance with HC-320 



Ring 
gasket 
shown 




Use radius in 
accordance 




Ring 
gasket 
shown 



Use any 
suitable 
type of 
gasket 



-1/2 A 



MA(A+B) 

Use radius in 
accordance with HC-320 




M = the total moment determined as in Section VIII, 
Division 1, Appendix 2, 2-6, except that for heads 
of the type shown in Fig. HC-311, sketch (c), a 
moment H r h r (which may add or subtract) shall 
be included in addition to the moment H D h D 
where 
H D = axial component of the membrane load in 
the spherical segment acting at the inside 
of the flange ring 
= 0JS5B 2 P 
h D = radial distance from the bolt circle to the 

inside of the flange ring 
H r = radial component of the membrane load in 
the spherical segment acting at the intersec- 
tion of the inside of the flange ring with the 
center line of the dished cover thickness 
= H D cot A 
h r = lever arm of force H r about centroid of 
flange ring 
P = design pressure for existing vessels 
r = inside knuckle radius 
S = maximum allowable stress value as given in Table 

HC-300 
T = flange thickness 

t = minimum required thickness of head plate after 
forming 



fl\ = angle formed by the tangent to the center line of 
the dished cover thickness at its point of intersec- 
tion with the flange ring, and a line perpendicular 
to the axis of the dished cover 
= arcsin [B/(2L + t)] 

NOTE: Since H,h r in some cases will subtract from the total moment, 
the moment in the flange ring when the internal pressure is zero may be 
the determining loading for the flange design. 

HC-311.1 Heads Concave to Pressure. Circular spher- 
ically dished heads with bolting flanges, concave to the 
pressure and conforming to the several types illustrated in 
Fig. HC-311, shall be designed in accordance with the 
following formulas: 

(a) Heads of the Type Shown in Fig. HC-311, Sketch (a) 
(1) Head thickness 



t = 



5PL 
65 



(2) Range thickness T: 



For ring gasket, 



T = ^ 



M 
SB 


~A + B~ 
A-B 



119 



2007 SECTION IV 



For full-faced gasket, 



and 



T -°*Js 



B(A + B)(C-B) 



A-B 



NOTE: The radial components of the membrane load in the spherical 
segment are assumed to be resisted by its flange. 

Within the range of ANSI B 16. 1-1975, the flange facings and drillings 
should conform to those standards and the thickness specified therein 
shall be considered as a minimum requirement. 

(b) Heads of the Type Shown in Fig. HC-311, Sketch (b) 
(1) Head thickness 



t = 



5PL 
65 



(2) Range thickness for ring gaskets shall be calcu- 
lated as follows: 

(a) For heads with round bolting holes, 



t = Q + 



l.S15M (C + B) 
SB{1C - 55) 



^ PL 
Q = 4S 



C + B 



1C-5B 



(I) 



(II) 



(b) For heads with bolting holes slotted through 
the edge of the head, 



Q + 



1.875M (C + £) 
SB(3C-B) 



„ PL 



C + B 



3C-B 



(IH) 



(IV) 



(3) Flange thickness for full face gaskets shall be 
calculated by the following formula: 



T = Q + 



q2 | 3BQ(C - B) 



(V) 



The value of Q in eq. (V) is calculated by eq. (II) for round 
bolting holes or by eq. (IV) for bolting holes slotted through 
the edge of the head. 

(4) The required flange thickness shall be T as calcu- 
lated in (2) or (3) above, but in no case less than the value 
of t calculated in (1). 

(c) Heads of the Type Shown in Fig. HC-311, Sketch (c) 

(1) Head thickness 



t = 



5PL 
65 



(2) Range thickness 

T = F+ J F 2 + J 
where 

PB^JAL 2 -B 2 



F = 



85 (A - B) 



j - Mo] A + B 
l SB \A-B 



HC-315 OPENINGS AND REINFORCEMENTS 

(a) The dimensional requirements in HG-320 through 
HG-328 are applicable to cast iron and shall be used in 
the design of openings and reinforcements in boilers and 
boiler parts. 

(b) Cast iron flanges, nozzles, and opening reinforce- 
ments that enter into the design calculations of the com- 
pleted boiler or boiler part, shall be cast integrally with 
the boiler or boiler part. 



HC-320 CORNERS AND FILLETS 

(a) A liberal radius shall be provided at projecting 
edges, reentrant corners, and the juncture of non-load- 
bearing heat-transmitting fins and pins where they connect 
to the body of the casting, in accordance with good foundry 
practice. Abrupt changes in surface contour and in wall 
thickness at junctures shall be avoided. 

(b) Fillets and transition sections between adjacent main 
pressure containment walls or integral attachments thereto, 
such as nozzles, lugs, supports, flanges, and bosses, shall 
have radii or the equivalent not less than one times the 
thickness of the thinner of the sections being joined. 



HC-325 WASHOUT OPENINGS 

All cast iron steam and hot water boilers shall be pro- 
vided with washout openings to permit the removal of any 
sediment that may accumulate therein. Washout plugs shall 
not be smaller than NPS 1 1 / 2 (DN 40) for boilers having 
gross internal volume more than 5 ft 3 (142 1). Washout 
plugs shall not be smaller than 1 in. (25 mm) for boilers 
having gross internal volume not more than 5 ft 3 (142 1). 
Washout openings may be used for return pipe connections 
and the washout plug placed in a tee so that the plug is 
directly opposite and as close as possible to the opening 
in the boiler. 



HC-330 ASSEMBLY METHOD 

Cast iron boilers may be assembled using internal con- 
nections, such as electrochemically compatible metallic 
push nipples or grommet seals, or external connections 
such as cast iron headers or threaded pipe headers. The 
completed boiler shall satisfactorily pass the hydrostatic 
test prescribed in HC-410. 



07 



120 



2007 SECTION IV 



ARTICLE 4 
TESTS 



HC-400 TESTS TO ESTABLISH DESIGN 
PRESSURE 

HC-401 GENERAL 

(a) The design pressure for a boiler or boiler parts, for 
which the strength cannot be computed with a satisfactory 
assurance of accuracy, shall be established in accordance 
with the requirement of this paragraph using the following 
test procedure. 

(b) Safety of testing personnel should be given serious 
consideration when conducting the bursting tests in 
HC-402. 

HC-401.1 Purpose for Which Tests May Be Used. 

The tests in these paragraphs may be used for the purpose 
of establishing the design pressure of those parts or compo- 
nent parts for which the thickness cannot be determined 
by means of design rules given in this Section. Design 
changes shall also require a retest. The maximum allowable 
working pressure of all other elements or component parts 
shall not be greater than that determined by means of the 
applicable design rules. 

HC-401.2 Frequency of Tests. The tests performed in 
HC-401.1 shall be repeated within every 5 year period. 
This testing period may be extended when parts are inter- 
mittently produced, in which case the tests shall be per- 
formed at the time of or before the first production run 
after the 5 year period. All requirements of HC-403 shall 
be met. 



Pr = 



HC-402 



BURSTING TEST PROCEDURE 



(a) The design pressure of any component part tested 
by this method shall be established by a hydrostatic test 
to failure by rupture of a full-size sample of such pressure 
part. As an alternative, the hydrostatic test may be stopped 
when the test pressure reaches a value that will, by the 
formula in (b), justify the design pressure. 

(b) The design pressure of any component part deter- 
mined by either method shall be based on hydrostatically 
testing three representative boilers or boiler parts. The 
lowest value of P B obtained shall be used in determining 
the value of P R in the following formula: 



Specified minimum tensile strength 1 
Average tensile strength of associ- 
ated test bar (see HC-402.2) 



where 
P R = test pressure per HC-402(a), psi (kPa) 



rg = lesi pressure per ni^-^uz^ 
P R = design pressure, psi (kPa) 



NOTE: Due to the geometry of parts of cast iron boilers, failure under 
hydrostatic tests is principally in bending. When an analysis of the test 
indicates failure occurred in bending, P R may be multiplied by 1.5. 

HC-402.1 Test Gages 

(a) An indicating gage shall be connected directly to 
the vessel. If the indicating gage is not readily visible to 
the operator controlling the pressure applied, an additional 
indicating gage shall be provided where it will be visible 
to the operator throughout the duration of the test. For 
large vessels, it is recommended that a recording gage be 
used in addition to indicating gages. 

(b) Dial indicating pressure gages used in testing shall 
be graduated over a range of about double the intended 
maximum test pressure, but in no case shall the range be 
less than 1 \ nor more than 4 times that pressure. Digital 
reading pressure gages having a wider range of pressure 
may be used provided the readings give the same or greater 
degree of accuracy as obtained with dial pressure gages. 

(c) All gages shall be calibrated against a standard dead- 
weight tester or a calibrated master gage. Gages shall be 
recalibrated at any time that there is reason to believe that 
they are in error. 

HC-402.2 Associated Test Bars. A separately cast test 
bar shall be produced, machined, and tested in accordance 
with the requirements of the tensile bar test procedure in 
Article 2 of Part HC for each of the three boilers or boiler 
sections to be tested to destruction [see HC-402(b)]. Each 
test bar shall be from the same ladle of iron from which 
is cast the boiler or boiler section to be subjected to burst- 
ing. The arithmetical average tensile strength, psi, of the 
three bars shall be determined and shall equal or exceed 
the minimum tensile strength, specified in Table HC-300, 
of the class of iron selected by the Manufacturer for use 



The specified tensile strength is the tensile strength for the class of 
iron set forth in Table HC-300. 



121 



2007 SECTION IV 



in the formula in HC-402(b) for determining the design 
pressure. In no case shall the actual tensile strength of any 
of the three test bars, used to determine this arithmetical 
average tensile strength, be more than 10% under the mini- 
mum tensile strength listed in Table HC-300 for the class 
of iron selected by the Manufacturer. The tensile strengths 
obtained from the associated test bars shall be recorded on 
the Manufacturer's Master Data Report for Boilers Con- 
structed From Cast Iron (Form H-5). 



HC-403 WITNESSING, RECORDING, AND 
CERTIFYING TESTS 

Tests to establish the design pressure of a boiler or boiler 
parts shall be witnessed by a Certified Individual (see HC- 
502.12). These bursting tests shall be recorded on the Man- 
ufacturer's Master Data Report for Boilers Constructed 
From Cast Iron as shown in Form H-5 and the completed 
form shall be certified by the designated responsible engi- 
neering head of the Manufacturer and his signature nota- 
rized. These forms shall be kept on file by the Manufacturer 
as a matter of record. 



HC-404 RATING OF PRODUCTION BOILERS 
BASED ON TESTS 

All boilers or boiler parts of the same material, design, 
and construction, whose design pressures are based on a 
test to destruction of a sample boiler or boiler part in 
accordance with HC-402, shall be considered to have 
design pressures equal to the maximum allowable working 



pressure thus determined and shall be subjected to a hydro- 
static test pressure in conformity with rules of HC-410. 



HC-410 HYDROSTATIC TEST 

All completed boilers or boiler parts shall satisfactorily 
pass the hydrostatic test prescribed in this paragraph. 

HC-410.1 Steam Boilers. All steam boilers shall have 
each individual section or boiler part subjected to a hydro- 
static test pressure of not less than 60 psig (400 kPa) at 
the shop where made. The assembled boiler shall be sub- 
jected to a hydrostatic test of not less than 45 psig (300 kPa). 

HC-410.2 Hot Water Boilers. All hot water heating 
or hot water supply boilers marked for maximum allowable 
working pressures not over 30 psi (200 kPa) shall have 
each individual section or boiler part subjected to a hydro- 
static test of not less than 60 psi (400 kPa) at the shop 
where made. Hot water heating and hot water supply boilers 
marked for maximum allowable working pressures over 
30 psi (200 kPa) shall have each individual section or 
boiler part subjected to a hydrostatic test of 2 l / 2 times the 
maximum allowable working pressure at the shop where 
made. The assembled boiler shall be subjected to a hydro- 
static test pressure not less than \\ times the maximum 
allowable working pressure. 

HC-410.3 Required Test Pressure. In making hydro- 
static pressure tests, the pressure shall be under such control 
that in no case shall the required test pressure be exceeded 
by more than 10 psi (70 kPa). 



07 



122 



2007 SECTION IV 



ARTICLE 5 
QUALITY CONTROL AND INSPECTION 



HC-501 GENERAL 

HC-501.1 Quality Control System. Each Manufac- 
turer 1 or shop assembler shall have and maintain a quality 
control system that will establish that all Code require- 
ments, including material, design, testing, fabrication, 
examination, and inspection (by the Manufacturer and shop 
assembler), shall be met. 

Providing that Code requirements are suitably identified, 
the system may include provisions for satisfying any 
requirements by the Manufacturer or shop assembler or 
user that exceed minimum Code requirements and may also 
include provision for quality control of non-Code work. In 
such systems, the Manufacturer or shop assembler may 
make changes in parts of the system that do not affect the 
Code requirements. 

The system that the Manufacturer or shop assembler 
uses to meet the requirements of this Section must be one 
suitable for his own circumstances. The necessary scope 
and detail of the system shall depend upon the complexity 
of the work performed and upon the size and complexity 
of the organization. A written description of the system 
the Manufacturer or shop assembler will use to produce a 
Code item shall be available for review. Depending upon 
the circumstances, the description may be brief or volu- 
minous. 

The written description may contain information of a 
proprietary nature relating to the Manufacturer's or shop 
assembler's processes. Therefore, the Code does not 
require any distribution of this information, except to the 
ASME Designee, as covered by HC-502. 1 1 .3. It is intended 
that information learned about the quality control system in 
connection with evaluation will be treated as confidential. 



HC-502 OUTLINE OF FEATURES TO BE 
INCLUDED IN THE WRITTEN 
DESCRIPTION OF THE QUALITY 
CONTROL SYSTEM 

The following is a guide to some of the features that 
should be covered in the written description of the quality 
control system. 



1 In Article 5, the Manufacturer referred to is the foundry who casts 
the boiler part or section and who may shop assemble it. 



HC-502.1 Product or Work Description. The quality 
control system shall contain a brief description of the prod- 
ucts the Manufacturer wishes to fabricate under the Code 
or the work the shop assembler wishes to accomplish under 
the Code. 

HC-502.2 Authority and Responsibility. The author- 
ity and responsibility of those in charge of the quality 
control system shall be clearly established. Persons per- 
forming quality control functions shall have sufficient and 
well-defined responsibility, the authority, and the organiza- 
tional freedom to identify quality control problems and to 
initiate, recommend, and provide solutions. 

HC-502.3 Organization. An organization chart show- 
ing the relationship between management and engineering, 
purchasing, manufacturing, inspection, and quality control 
is required to reflect the actual organization. The purpose 
of this chart is to identify and associate the various organi- 
zational groups with the particular function for which they 
are responsible. The Code does not intend to encroach on 
the Manufacturer's or shop assembler's right to establish 
and, from time to time, alter whatever form of organization 
the Manufacturer or shop assembler considers appropriate 
for his Code work. 

HC-502. 4 Drawings, Design Calculations, Test 
Results, and Specification Control. The Manufacturer's 
or shop assembler's quality control system shall provide 
procedures that will insure that the latest applicable draw- 
ings, design calculations, test results, specifications, and 
instructions required by the Code, as well as authorized 
changes, are used for manufacture, assembly, examination, 
inspection, and testing. 

HC-502.5 Material Control. The Manufacturer or 
shop assembler shall include a system that requires verifi- 
cation that the material meets the requirements of Article 
2 of Part HC. The system shall assure that only the intended 
material is used in Code construction. 

HC-502.6 Examination Program. The Manufacturer' s 
or shop assembler's quality control system shall describe 
the bursting test procedure and the fabrication operations, 
sufficiently to determine at which stages specific examina- 
tions are to be performed. 



123 



2007 SECTION IV 



HC-502.7 Correction of Nonconformities. There shall 
be a system for correction of nonconformities. A noncon- 
formity is any condition that does not comply with the 
applicable rules of this Section. Nonconformities must be 
corrected or eliminated before the completed component 
can be considered to comply with this Section. 

HC-502.8 Calibration of Measurement and Test 
Equipment. The Manufacturer or shop assembler shall 
have a system for calibration of all equipment used for 
examination, measuring, and testing to fulfill the require- 
ments of this Section. 

HC-502.9 Sample Forms. The forms used in the qual- 
ity control system and any detailed procedures for their 
use shall be available for review. The written description 
shall make necessary references to these forms. The forms 
exhibited shall be marked "Sample" and completed in a 
manner typical of actual production and test procedures. 

HC-502.10 Retention of Records. The Manufacturer 
or shop assembler shall have a system for retaining the 
Manufacturer's Data Forms for a minimum of 15 years. 

HC-502.11 ASME Designee 
HC-502.11.1 The written description of the quality 
control system shall include reference to the ASME Des- 
ignee. 

HC-502.11.2 The Manufacturer or shop assembler 
shall make available to the ASME Designee a controlled 
copy of the written description of the quality control 
system. 

HC-502.11.3 The Manufacturer's or shop assem- 
bler's quality control system shall provide for the ASME 
Designee to have access to all drawings, calculations, speci- 
fications, procedures, process sheets, repair procedures, 
records, test results, and any other documents as necessary 
for the ASME Designee to perform his review in accor- 
dance with this Section. The Manufacturer or shop assem- 
bler may provide such access either to his own files of such 
documents or by providing copies to the ASME Designee. 

HC-502.12 Certified Individual (CI). A Certified Indi- 
vidual shall provide oversight of the activities that affect the 
proper utilization of the "H" symbol on cast iron sections as 
outlined in Part HC. 

HC-502.12.1 Requirements for a Certified Indi- 
vidual (CI). A Certified Individual (CI) shall 

(a) be an employee of the Manufacturer. 

(b) be qualified by the Manufacturer. Qualifications 
shall include as a minimum: 

(J) knowledge of the requirements of Parts HG and 
HC 

(2) knowledge of the Manufacturer' s quality program 

(3) training commensurate with the scope, complex- 
ity, or special nature of the activities to which oversight 
is to be provided 



(c) have a record, maintained and certified by the Manu- 
facturer, containing objective evidence of the qualifications 
and training of the CI. 

(d) not be directly involved in the production of cast 
iron sections for which he is performing the duties listed 
in HC-502.12.2. 

HC-502.12.2 Duties of a Certified Individual (CI). 

A Certified Individual (CI) shall 

(a) witness tests to determine the design pressure of a 
boiler or boiler part as outlined in HC-403 

(b) verify that cast iron sections marked with the "H" 
symbol have a current H-5 Manufacturers Master Data 
Report for Boilers Constructed of Cast Iron 

(c) review the tensile and chemical composition tests 
records, verifying that they meet the requirements of Arti- 
cle 2 of Part HC 

(d) review documentation to verify that cast iron sec- 
tions marked with the "H" symbol have been hydrostati- 
cally tested as required by HC-410 

(e) sign the Certificates of Conformance as outlined in 
HC-520 



HC-510 EXAMINATION 

Examination of each boiler or boiler part shall be in 
compliance with Article 2 of Part HC. Hydrostatic tests 
shall be conducted as required in HC-410 by the Manufac- 
turer or shop assembler, and there shall be a means of 
identifying acceptable boiler sections or parts. 



HC-520 CERTIFICATES OF CONFORMANCE 

Cast iron boiler sections marked with the "H" symbol 
shall be recorded on Certificates of Conformance as 
follows: 

(a) A Certificate of Conformance Form HC-1 listing 
the pattern number, cast date, and quantity of castings 
marked with the "H" symbol shall be filled out and signed 
by a representative of the Manufacturer, and signed by a 
Certified Individual. 

(1) Multiple cast iron boiler sections may be recorded 
on the same HC-1 form. 

(2 ) Castings with the same cast date may be recorded 
on the same line. 

(b) A Certificate of Conformance Form HC-2 listing 
the pattern number, MAWP, hydrostatic test pressure and 
quantity of cast iron sections that have satisfactorily passed 
the hydrostatic test required in HC-410 shall be filled out 
and signed by a respresentative of the Manufacturer, and 
signed by a Certified Individual. 

(1 ) Multiple cast iron boiler sections may be recorded 
on the same HC-2 form. 



124 



2007 SECTION IV 



(c) The Manufacturer's written quality control program 
shall include requirements for completion of the Certifi- 
cates of Conformance and retention by the Manufacturer 
for a minimum of 5 years. 

( d) The representative of the Manufacturer and Certified 
Individual above shall not be the same person. 



125 



2007 SECTION IV 



07 



PART HA 

REQUIREMENTS FOR BOILERS 

CONSTRUCTED OF 

CAST ALUMINUM 



ARTICLE 1 
GENERAL 



HA-100 SCOPE 

The rules in Part HA are applicable to hot water heating boilers that are constructed primarily of cast aluminum 
sections and shall be used in conjunction with general requirements of Part HG of this section. 



126 



2007 SECTION IV 



ARTICLE 2 
MATERIAL REQUIREMENTS 



HA-200 GENERAL MATERIAL 
REQUIREMENTS 

(a) All materials used for cast sections of heating boilers 
that are constructed primarily of cast aluminum shall meet 
the requirements of this Article and material specifications 
listed in HF-300.2 for aluminum castings. 

(b) External appurtenances such as cast or welded head- 
ers and other miscellaneous pressure parts shall be manu- 
factured from materials permitted under Part HF-203. The 
design pressure for these pressure parts for which the 
strength cannot be computed shall be established in accor- 
dance with HG-500. 

(c) Maximum allowable water temperature is 250°F 
(120°C). 



HA-201 WORKMANSHIP, FINISH, AND 
REPAIR 

(a) The surface of the casting shall conform substan- 
tially to the dimensions on drawings or to the dimensions 
predicated by the pattern, and be free from injurious 
defects. The surface of the casting shall be free from burnt- 
on sand and shall be reasonably smooth. Risers, fins, and 
projections used to facilitate the making of the casting 
shall be removed. In other respects, they shall conform 
to whatever requirements may be specially agreed upon 
between the Manufacturer and shop assembler when the 
shop assembler is separate from the Manufacturer. 

(b) Seepage about chaplets, and minor leakage defects, 
may be repaired by plugging, impregnation, or welding as 
directed in the following: 

(1) Provided the surrounding metal is sound, a minor 
leak may be plugged with a solid aluminum, brass, or 
stainless steel tapered thread pipe plug. The maximum size 
of the pipe plug shall be NPS 1 (DN 25) and there shall 
be no less than four full standard pipe threads in the section 
metal. (See Table HC-213.) 

(2) Impregnation may be used to correct seepage 
leaks in aluminum alloy castings under the following con- 
ditions: 

(a) Limitations of the extent and frequency of 
impregnation shall be as approved in the Manufacturer's 
written quality control system. 



(b) Impregnated castings shall be marked in a way 
that is approved in the Manufacturer's written quality con- 
trol system. The method of marking shall be documented 
in the shop assembler's QC manual when the shop assem- 
bler is separate from the Manufacturer. 

(c) Control of the impregnation process shall be 
addressed in the Manufacturer's QC manual. 

(d) The impregnation material shall meet the 
requirements of Class 1 material as defined in 
MIL-I-17563C. 1 

(e) Impregnation shall be accomplished in accor- 
dance with MIL-STD-276. 1 

(f) Welding shall not be performed on castings 
after impregnation. 

(g) The Manufacturer shall hydrostatically test 
each casting per HA-410 after impregnation. 

(3) Castings may be repaired by welding only as 
approved in the Manufacturer's and shop assemblers writ- 
ten quality control system. 

(a) Limitations on the extent and frequency of such 
repairs, and methods of inspection of repaired areas shall 
also be covered in the written quality control system. 

(b) The welding procedure and welders shall be 
qualified in accordance with Section IX. 

(c) Control of the welding process shall be 
addressed in the quality control manual. 

(d) Welding shall not be performed after impreg- 
nation. 



HA-202 EXAMINATIONS AND TESTS 

The Manufacturer shall be responsible for all examina- 
tions and tests. When requested by a shop assembler, the 
Manufacturer shall agree to permit a representative of the 
shop assembler to have entry, at the time while work under 
the contract of the shop assembler is being performed, to 
all parts of the Manufacturer's works that concern the 
castings manufactured to the requirements of this Article. 
All examinations and tests shall be made at the place of 
manufacture prior to shipment, unless otherwise specified 



Military specification is available from Standardization Documents 
Order Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 
19111-5094. 



127 



2007 SECTION IV 



and shall be so conducted as not to interfere unnecessarily 
with the operation of the works. 



HA-203 TEST RECORDS 

The Manufacturer shall record and retain all test results 
required by this Article for a period of at least 1 year. The 
test results shall be readily identifiable with the casting 
represented by the test results. 



128 



2007 SECTION IV 



ARTICLE 3 
DESIGN 



HA-300 MAXIMUM ALLOWABLE STRESS 
VALUES 

(a) Table HF-300.2 gives the maximum allowable stress 
values in tension for aluminum castings. 

(b) Stress values in Table HF-300.2 shall be used in 
calculations employing the available formulas in Part HG 
when applicable to the geometry of the boiler or boiler 
parts. Where the design pressure cannot be calculated under 
the available formulas, then the design pressure of the part 
in question shall be established in accordance with the 
provisions of HA-400. 

HA-301 HEADS AND SPHERICALLY SHAPED 
COVERS 

Circular spherically dished heads with bolting flanges, 
concave to the pressure and conforming to the several types 
illustrated in Fig. HC-311 shall be designed in accordance 
withHC-311 and HC-3 11.1. 

HA-302 OPENINGS AND REINFORCEMENTS 

(a) The dimensional requirements in HG-320 through 
HG-328 are applicable to aluminum and shall be used in 
the design of openings and reinforcements in boilers and 
boiler parts. 

(b) Cast flanges, nozzles, and opening reinforcements 
that enter into design calculations of the completed boiler 
or boiler part shall be cast integrally with the boiler or 
boiler part. 

(c) Core holes in aluminum alloy castings may be 
plugged with electrochemically compatible push-in sealing 
caps under the following conditions: 

(1 ) The sealing caps shall only be used to plug holes 
required for the manufacturing process, such as core sand 
removal. They shall not be used for repair. 

(2 ) The dimensions of the plug and mating hole shall 
conform to manufacturers' standards or such published 
standards as DIN 443. ! 

(3) Proof testing to establish design pressure is 
required and shall comply with HA-402. 



(4) The shop assembler shall hydrostatically test each 
casting per HA-406. 



HA-303 



CORNERS AND FILLETS 



1 English translations of DIN 443 and its references can be obtained 
from DIN Deutsches Institute fur Normung e. V., Burggrafenstrasse, 
10787 Berlin, Germany, Tel: +49 30 2601-0, Fax: +49 30 2601-1231. 



(a) A liberal radius shall be provided at projecting edges 
and reentrant corners, and the juncture of non-load-bearing 
heat transmitting fins and pins where they connect to the 
body of the casting, in accordance with good foundry prac- 
tice. Abrupt changes in surface contour and in wall thick- 
ness at junctures shall be avoided. 

(b) Fillets and transition sections between adjacent main 
pressure containment walls or integral attachments thereto, 
such as nozzles, lugs, supports, flanges, and bosses, shall 
have radii or the equivalent not less than one times the 
thickness of the thinner of the sections being joined. 



HA-304 WASHOUT OPENINGS 

All cast aluminum hot water boilers shall be provided 
with washout openings to permit the removal of any sedi- 
ment that may accumulate therein. Washout plugs shall 
not be smaller than NPS 1 1 / 2 (DN 40) for boilers having a 
gross internal volume more than 5 ft 3 (142 1). Washout 
plugs shall not be smaller than NPS 1 (DN 25) for boilers 
having gross internal volumes from 2.0 ft 3 (57 1) through 
5.0 ft 3 (142 1). Washout plugs shall not be smaller than 
NPS % (DN 20) for boilers having gross internal volumes 
less than 2.0 ft 3 (57 1). Washout openings may be used for 
return pipe connections and the washout plug placed in a 
tee so that the plug is directly opposite and as close as 
possible to the opening in the boiler. 



HA-305 ASSEMBLY METHOD 

Cast aluminum boilers may be assembled using internal 
connections, such as electrochemically compatible metallic 
push nipples, grommet seals, or external connections such 
as cast headers or threaded pipe headers. The complete 
boiler shall satisfactorily pass the hydrostatic test pre- 
scribed in HA-406. 



129 



2007 SECTION IV 



ARTICLE 4 
TESTS 



HA-400 TESTS TO ESTABLISH DESIGN 
PRESSURE 

HA-401 GENERAL 

(a) The design pressure for a boiler or boiler parts for 
which the strength cannot be computed shall be established 
in accordance with the requirements of this paragraph using 
the following test procedure. 

(b) Safety of testing personnel should be given serious 
consideration when conducting the bursting tests in 
HA-402. 

HA-401.1 Purpose for Which Tests May Be Used. 

The tests in these paragraphs may be used for the purpose 
of establishing the design pressure of those parts or compo- 
nent parts for which the thickness cannot be determined 
by means of design rules given in this Section. Design 
changes shall also require a retest. The maximum allowable 
working pressure of all other elements or component parts 
shall not be greater than that determined by means of the 
applicable design rules. 

HA-401.2 Frequency of Tests. The tests performed in 
HA-401.1 shall be repeated within every 5-year period. 
This testing period may be extended when parts are inter- 
mittently produced, in which case the tests shall be per- 
formed at the time of or before the first production run 
after the 5-year period. All requirements of HA-403 shall 
be met. 

HA-402 BURSTING TEST PROCEDURE 

(a) The design pressure of any component part tested 
by this method shall be established by a hydrostatic test 
to failure by rupture of a full-size sample of such pressure 
part. As an alternative, the hydrostatic test may be stopped 
when the test pressure reaches a value that will, by the 
formula in HA-402(b), justify the design pressure. 

(b) The design pressure of any component part deter- 
mined by this method shall be based on hydrostatically 
testing three representative boilers or boiler parts. The 
lowest value of P B obtained shall be used in determining 
the value of P R in the following formula: 



Pr = -=- x 



S„ or S„ 



*% 



where 

P B = test pressure per HA-402(a), psi (kPa) 

P R = design pressure, psi (kPa) 
S = specified minimum tensile strength, psi (kPa) 

S a = average actual tensile strength of test specimens, 
psi (kPa) 

S m = maximum tensile strength of range of specimens, 
psi (kPa) 

S\ = maximum allowable stress at room temperature, 
psi (kPa) 

S 2 = maximum allowable strength at design tempera- 
ture, psi (kPa) 



HA-403 TEST GAGES 

(a) An indicating gage shall be connected directly to 
the vessel. Intermediate pipe and fittings may be used 
provided there are no intervening valves. If the indicating 
gage is not readily visible to the operator controlling the 
pressure applied, an additional indicating gage shall be 
provided where it will be visible to the operator throughout 
the duration of the test. For large vessels, it is recommended 
that a recording gage be used in addition to indicating 
gages. 

(b) Dial indicating pressure gages used in testing shall 
be graduated over a range of about double the intended 
maximum test pressure, but in no case shall the range be 
less than \\ or more than 4 times that pressure. Digital 
reading pressure gages having a wider range of pressure 
may be used provided the readings give the same or greater 
degree of accuracy as obtained with dial pressure gages. 

(c) All gages shall be calibrated against a standard dead- 
weight tester or a calibrated master gage. Gages shall be 
recalibrated at any time that there is reason to believe that 
they are in error. 



HA-404 WITNESSING, RECORDING, AND 
CERTIFYING TESTS 

Test to establish the design pressure of a boiler or boiler 
parts shall be witnessed by a Certified Individual. See 
HA-502.12. These bursting tests shall be recorded on the 



130 



2007 SECTION IV 



Manufacturer's Master Data Report for Boilers Con- 
structed From Cast Aluminum as shown in Form H-5A. 
The completed form shall be certified by the designated 
responsible engineering head of the Manufacturer and his 
signature on the form shall be notarized. These forms shall 
be kept on file by the Manufacturer as a matter of record. 



HA-405 RATING OF PRODUCTION BOILERS 
BASED ON TESTS 

All boilers or boiler parts of the same material, design, 
and construction, whose design pressures are based on a 
test to destruction of a sample boiler or boiler part in 
accordance with HA-402, shall be considered to have 
design pressures equal to the maximum allowable working 
pressure thus determined and shall be subjected to a hydro- 
static test pressure in conformity with rules of HA-406. 



HA-406 HYDROSTATIC TEST 

All completed boilers or boiler parts shall satisfactorily 
pass the hydrostatic test prescribed in this paragraph. 

HA-406.1 Hot Water Boilers. All hot water heating 
boilers marked for maximum allowable working pressures 
not over 30 psi (207 kPa) shall have each individual section 
or boiler part subjected to a hydrostatic test of not less 
than 60 psi (414 kPa) at the shop where made. Hot water 
heating boilers marked for maximum allowable working 
pressures over 30 psi (207 kPa) shall have each individual 
section or boiler part subjected to a hydrostatic test of 2 l / 2 
times the maximum allowable working pressure at the shop 
where made. The assembled boiler shall be subjected to a 
hydrostatic test pressure not less than 1 V 2 times the maxi- 
mum allowable working pressure. 

HA-406.2 Required Test Pressure. In making hydro- 
static pressure tests, the pressure shall be under such control 
that in no case shall the required test pressure be exceeded 
by more than 10 psi (69 kPa). 



131 



2007 SECTION IV 



ARTICLE 5 
QUALITY CONTROL AND INSPECTION 



HA-501 GENERAL 

HA-501.1 Quality Control System. Each Manufac- 
turer 1 or shop assembler shall have and maintain a quality 
control system that will establish that all Code require- 
ments, including material, design, testing, fabrication, 
examination, and inspection (by the Manufacturer and shop 
assembler) shall be met. 

Providing that Code requirements are suitably identified, 
the system may include provisions for satisfying any 
requirements by the Manufacturer or shop assembler or 
user that exceed minimum Code requirements and may also 
include provision for quality control of non-Code work. In 
such systems, the Manufacturer or shop assembler may 
make changes in parts of the system, which do not affect 
the Code requirements. 

The system that the Manufacturer or shop assembler 
uses to meet the requirements of this Section must be one 
suitable for his own circumstances. The necessary scope 
and detail of the system shall depend upon the complexity 
of the work performed and the size and complexity of 
the organization. A written description of the system the 
Manufacturer or shop assembler will use to produce a Code 
item shall be available for review. Depending upon the 
circumstances, the description may be brief or voluminous. 

The written description may contain information of a 
proprietary nature relating to the Manufacturer's or shop 
assembler's processes. Therefore, the Code does not 
require any distribution of this information, except to the 
ASME Designee, as covered by HA-502. 1 1 .3. It is intended 
that information learned about the quality control system in 
connection with evaluation will be treated as confidential. 



HA-502 OUTLINE OF FEATURES TO BE 
INCLUDED IN THE WRITTEN 
DESCRIPTION OF THE QUALITY 
CONTROL SYSTEM 

The following is a guide to some of the features that 
should be covered in the written description of the quality 
control system. 



1 In Article 5, the Manufacturer referred to is the foundry who casts 
the boiler part or section and who may shop assemble it. 



HA-502.1 Product or Work Description. The quality 
control system shall contain a brief description of the prod- 
ucts the Manufacturer wishes to fabricate under the Code 
or the work the shop assembler wishes to accomplish under 
the Code. 

HA-502.2 Authority and Responsibility. The author- 
ity and responsibility of those in charge of the quality 
control shall be clearly established. Persons performing 
quality control functions shall have sufficient and well- 
defined responsibility, the authority, and the organizational 
freedom to identify quality control problems and to initiate, 
recommend, and provide solutions. 

HA-502.3 Organization. An organization chart show- 
ing the relationship between management and engineering, 
purchasing, manufacturing, inspection and quality control 
is required to reflect the actual organization. The purpose 
of this chart is to identify and associate the various organi- 
zational groups with the particular function for which they 
are responsible. The Code does not intend to encroach on 
the Manufacturer's or shop assembler's right to establish 
and, from time to time, alter whatever form of organization 
the Manufacturer or shop assembler considers appropriate 
for his Code work. 

HA-502. 4 Drawings, Design Calculations, Test 
Results, and Specification Control. The Manufacturer's 
or shop assembler's quality control system shall provide 
procedures that will insure that the latest applicable draw- 
ings, design calculations, test results, specifications, and 
instructions required by the Code, as well as authorized 
changes, are used for manufacture, assembly, examination, 
inspection, and testing. 

HA-502.5 Material Control. The Manufacturer or 
shop assembler shall include a system that requires verifi- 
cation that the material meets the requirements of Article 2 
of Part HA. The system shall assure that only the intended 
material is used in Code construction. 

HA-502.6 Examination Program. The Manufacturer' s 
or shop assembler's quality control system shall describe 
the bursting test procedure and the fabrication operations, 
sufficiently to determine at which stages specific examina- 
tions are to be performed. 



132 



2007 SECTION IV 



HA-502.7 Correction of Nonconformities. There shall 
be a system for correction of nonconformities. A noncon- 
formity is any condition that does not comply with the 
applicable rules of this Section. Nonconformities must be 
corrected or eliminated before the completed component 
can be considered to comply with this Section. 

HA-502.8 Calibration of Measurement and Test 
Equipment. The Manufacturer or shop assembler shall 
have a system for calibration of all equipment used for 
examination, measuring, and testing to fulfill the require- 
ments of this Section. 

HA-502.9 Sample Forms. The forms used in the qual- 
ity control system and any detailed procedures for their 
use shall be available for review. The written description 
shall make necessary references to these forms. The forms 
exhibited shall be marked "Sample" and completed in a 
manner typical of actual production and test procedures. 

HA-502.10 Retention of Records. The Manufacturer 
or shop assembler shall have a system for retaining the 
Manufacturer's Data Forms for a minimum of 15 years. 

HA-502.11 ASME Designee 

HA-502.11.1. The written description of the quality 
control system shall include reference to the ASME Des- 
ignee. 

HA-502.11.2. The Manufacturer or shop assembler 
shall make available to the ASME Designee a controlled 
copy of the written description of the quality control 
system. 

HA-502.11.3. The Manufacturer's or shop assem- 
bler's quality control system shall provide for the ASME 
Designee to have access to all drawings, calculations, speci- 
fications, procedures, process sheets, repair procedures, 
records, test results, and any other documents as necessary 
for the ASME Designee to perform his review in accor- 
dance with this Section. The Manufacturer or shop assem- 
bler may provide such access either to his own files of such 
documents or by providing copies to the ASME designee. 

HA-502.12 Certified Individual (CI). A Certified Indi- 
vidual shall provide oversight of the activities that affect 
the proper utilization of the "H" symbol on cast aluminum 
sections as outlined in Part HA. 

HA-502.12.1 Requirements for a Certified Indi- 
vidual (CI). A Certified Individual shall 

(a) be an employee of the Manufacturer 



(b) be qualified by the Manufacturer. Qualifications 
shall include the following as a minimum: 

(1) knowledge of the requirements of Parts HG, HC, 
and HA 

(2) knowledge of the Manufacturer's quality control 
system 

(3) training commensurate with the scope, complex- 
ity, or special nature of the activities to which oversight 
is provided 

(c) have a record, maintained and certified by the Manu- 
facturer, containing objective evidence of the qualifications 
and training of the CI 

(d) not be directly involved in the production of cast 
aluminum sections for which he is performing the duties 
listed in HA-502.12.2 

HA-502.12.2 Duties of a Certified Individual (CI). 

A Certified Individual (CI) shall 

(a) witness tests to determine the design pressure of 
boiler or boiler part as outlined in HA-403 

(b) verify that cast aluminum sections marked with the 
"H" symbol shall have a current H-5A Manufacturer's 
Master Data Report for Boilers Constructed Primarily of 
Cast Aluminum 

(c) review the tensile and chemical composition tests 
records, verifying that they meet the requirements of 
Table HF-300.2 

(c) review documentation to verify that cast aluminum 
sections marked with the "H" symbol have been hydrostati- 
cally tested as required by HA-410 

(d) sign the Certificates of Conformance as outlined in 
HA-520 



HA-503 EXAMINATION 

Examination of each boiler or part shall be in compliance 
with Article 2 of Part HA. Hydrostatic tests shall be con- 
ducted as required in HA-410 by the Manufacturer or shop 
assembler, and there shall be a means of identifying accept- 
able boiler sections or parts. 



HA-504 CERTIFICATES OF CONFORMANCE 

Cast aluminum boiler sections marked with the "H" 
symbol shall be recorded on Certificates of Conformance 
as follows: 

(a) A Certificate of Conformance Form HA-1 listing 
the pattern number, cast date, and quantity of castings 
marked with the "H" symbol shall be filled out and signed 
by a representative of the Manufacturer and signed by a 
Certified Individual. 

(1 ) Multiple cast aluminum boiler sections may be 
recorded on the same HA-1 form. 



133 



2007 SECTION IV 



(2) Castings with the same casting date may be 
recorded on the same line. 

(b) A Certificate of Conformance Form HA-2 listing 
the pattern number, MAWP, hydrostatic test pressure, and 
quantity of cast aluminum sections that have satisfactorily 
passed the hydrostatic test required in HA-410 shall be 
filled out and signed by a representative of the Manufac- 
turer, and signed by a Certified Individual. Multiple cast 



aluminum boiler sections may be recorded on the same 
HA-2 form. 

(c) The Manufacturer's written quality control system 
shall include requirements for completion of the Certifi- 
cates of Conformance and retention by the Manufacturer 
for a minimum of 5 years. 

( d) The representative of the Manufacturer and Certified 
Individual above shall not be the same person. 



• 



134 



2007 SECTION IV 



PART HLW 
REQUIREMENTS FOR POTABLE- 
WATER HEATERS 



INTRODUCTION 



The following is a brief introduction to Part HLW. It is 
general in nature, and should not be considered as a substi- 
tute for actual review of appropriate articles of the docu- 
ment. However, this will give the user a better 
understanding of the purpose, requirements, and intent of 
Part HLW. 

Part HLW applies to water heaters in commercial or 
industrial sizes providing corrosion resistance for supply- 
ing potable hot water for commercial purposes at pressures 
not exceeding 160 psig (1 100 kPa) and temperatures not 
exceeding 210°F (99°C). 

Part HLW does not apply to residential size water heat- 
ers, which are excluded by provisions of HLW- 101. 

Differences in applicable criteria for water heaters versus 
hot water heating boilers are as follows: 

(a) In a water heater, the temperature of the water is 
limited to a maximum of 210°F (99°C). 

(b) A water heater is provided with a corrosion resistant 
lining or constructed with corrosion resistant materials. 

(c) A water heater is intended to supply potable hot 
water with all makeup from a potable water supply system. 
Vessels built under the rules of Part HLW may be used 
for storage of potable water. 

The following is a brief outline of the contents of each 
Article of Part HLW. 

Article 1 — General 

The scope of Part HLW is given, and the service restric- 
tion and exemption are stated. 

Article 2 — Materials 

The material requirements for the linings permitted are 
specified as well as the lining thickness requirements. The 



material requirements specified for the lining materials 
were, in general, taken from existing standards by 
abstracting those requirements that were considered to be 
those essential for the applications covered by these rules. 

Article 3 — Design 

The design criteria for water heaters is given in Article 3. 
The pressure is specified as a maximum allowable working 
pressure of 160 psi (1 100 kPa) with a minimum of 100 psi 
(700 kPa). The maximum water temperature permitted is 
210°F (99°C). 

The maximum allowable working pressure of the water 
heater shall be established in accordance with the proof 
test provision of HLW-500. As an alternative, stress values 
in Table HLW-300 may be used in calculations employing 
the available formulas when applicable to the geometry of 
the lined water heater or parts. 

Article 4 — Weldments 

The provisions for weldment joint design are similar to 
those given elsewhere in this Section and in Section VIII, 
Division 1. In addition, some acceptable joint designs are 
provided that have been commonly used in the construction 
of water heaters and have provided satisfactory service 
performance. 

Article 5 — Tests 

Proof test procedure is delineated for establishing the 
maximum allowable working pressure of a water heater 
or parts, and this test is required to be witnessed and 
accepted by the Authorized Inspector. The Manufacturer's 



135 



2007 SECTION IV 



Master Data Proof Test Report for Lined Water Heaters 
shall be certified by the designated responsible engineering 
head of the Manufacturer and the forms shall be kept on 
file by the Manufacturer as a matter of record. 

Article 6 — Inspection and Stamping 

Inspection and stamping requirements for water heaters 
are given. An "HLW" Code Symbol Stamp is provided 
for water heaters made in accordance with Part HLW of 
Section IV. 

Article 7 — Controls 

Each water heater is required to have an operating con- 
trol and a separate high-limit temperature-actuated control 



that shuts off the fuel supply in case of operating control 
failure. Water heaters should be equipped with suitable 
primary safety controls, safety limit switches, burners, or 
electric elements as appropriate and as required by a nation- 
ally recognized standard. Examples of these nationally rec- 
ognized standards are listed. 



Article 8 — Installation 

Some acceptable piping installations are shown. Provi- 
sions for the installation of safety relief valves and other 
valves are given. 



136 



2007 SECTION IV 



ARTICLE 1 
GENERAL 



HLW-100 SCOPE 

(a) The rules in Part HLW apply to water heaters and 
water storage tanks with corrosion resistance for supplying 
potable hot water. The foreword provides the basis for 
these rules. Part HLW is not intended to apply to hot water 
heating boilers. 

(b) This Part contains mandatory requirements, specific 
prohibitions, and nonmandatory guidance for materials, 
designs, fabrication, examination, inspection, testing, certi- 
fication, and pressure relief. 

(c) Laws or regulations issued by a municipality, state, 
provincial, federal, or other enforcement or regulatory body 
having jurisdiction at the location of an installation, estab- 
lish the mandatory applicability of these rules, in whole 
or in part. 



HLW-101 SERVICE RESTRICTION AND 
EXCEPTION 

HLW-101. 1 Service Restriction. The rules of Part 
HLW are restricted to potable water heaters and water 
storage tanks for operation at pressures not exceeding 160 
psi (1 100 kPa) and water temperatures not in excess of 
210°F (99°C). 

HLW-101.2 Exception. Based on the Committee's 
consideration, water heaters are exempted when none of 
the following limitations is exceeded: 

(a) heat input of 200,000 Btu/hr (60 kW) 

(b) water temperature of 210°F (99°C) 

(c) nominal water-containing capacity of 120 gal 
(450 1), except that they shall be equipped with safety 
devices in accordance with the requirements of HLW-800 



HLW-102 PERMISSIBLE STAMPING 

Any water heater or storage tank that meets all of the 
requirements of Part HLW, including those for inspection, 



may be stamped with the Code HLW Symbol even though 
exempted from such stamping. 

HLW-103 UNITS 

Either U.S. Customary, SI, or any local customary units 
may be used to demonstrate compliance with all require- 
ments of this edition (e.g., materials, design, fabrication, 
examination, inspection, testing, certification, and over- 
pressure protection). 

In general, it is expected that a single system of units 
shall be used for all aspects of design except where unfeasi- 
ble or impractical. When components are manufactured at 
different locations where local customary units are different 
than those used for the general design, the local units 
may be used for the design and documentation of that 
component. Similarly, for proprietary components or those 
uniquely associated with a system of units different than 
that used for the general design, the alternate units may be 
used for the design and documentation of that component. 

For any single equation, all variables shall be expressed 
in a single system of units. When separate equations are 
provided for U.S. Customary and SI units, those equations 
must be executed using variables in the units associated 
with the specific equation. Data expressed in other units 
shall be converted to U.S. Customary or SI units for use 
in these equations. The result obtained from execution of 
these equations may be converted to other units. 

Production, measurement and test equipment, drawings, 
welding procedure specifications, welding procedure and 
performance qualifications, and other fabrication docu- 
ments may be in U.S. Customary, SI, or local customary 
units in accordance with the fabricator's practice. When 
values shown in calculations and analysis, fabrication doc- 
uments, or measurement and test equipment are in different 
units, any conversions necessary for verification of Code 
compliance and to ensure that dimensional consistency is 
maintained shall be in accordance with the following: 

(a) Conversion factors shall be accurate to at least four 
significant figures. 

( b) The results of conversions of units shall be expressed 
to a minimum of three significant figures. 



137 



2007 SECTION IV 



Conversion of units, using the precision specified above 
shall be performed to assure that dimensional consistency 
is maintained. Conversion factors between U.S. Customary 
and SI units may be found in the Nonmandatory 
Appendix M, Guidance for the Use of U.S. Customary and 
SI Units in the ASME Boiler and Pressure Vessel Code. 
Whenever local customary units are used the Manufacturer 
shall provide the source of the conversion factors, which 
shall be subject to verification and acceptance by the 
Authorized Inspector or Certified Individual. 

Material that has been manufactured and certified to 
either the U.S. Customary or SI material specification (e.g., 



SA-516M) may be used regardless of the unit system used 
in design. Standard fittings (e.g., flanges, elbows, etc.) that 
have been certified to either U.S. Customary units or SI 
units may be used regardless of the unit system used in 
design. 

All entries on a Manufacturer's Data Report and data 
for Code required nameplate marking shall be in units 
consistent with the fabrication drawings for the component 
using U.S. Customary, SI, or local customary units. It is 
acceptable to show alternate units parenthetically. Users 
of this Code are cautioned that the receiving Jurisdiction 
should be contacted to ensure the units are acceptable. 



138 



2007 SECTION IV 



ARTICLE 2 
MATERIAL REQUIREMENTS 



HLW-200 LINING 

(a) Glass Lined. Glass lining shall be of an analysis 
intended for use in hot water service and the minimum 
average thickness shall be 0.005 in. (0.13 mm). The walls, 
ends, and other parts that are of steel and are glass lined 
shall be of a quality that is suitable for glass lining by the 
manufacturer's glass lining process. Glass lining may be 
applied to parts before assembly. The surfaces of the water 
heater vessel that are exposed to hot water shall have a 
coating with a minimum number of discontinuities, and 
the discontinuities shall average not more than \ in. 2 /ft 2 
(8 cm 2 /m 2 ) of internal surface excluding edges and fittings. 
Thinning at corners may not extend over % in. (6 mm) 
from the edge. 

(b) Galvanized. The galvanized coating shall be based 
upon at least 1 oz of zinc /ft 2 (3 gal/m 2 ) of surface based 
upon mathematical calculations corresponding to a coating 
thickness of 0.0017 in. (0.043 mm). The weight of the zinc 
coating shall be determined by weighing the water heater 
before galvanizing and again after the coating is applied. 

The zinc used for coating shall conform to ASTM B 6, 
Specification for Zinc (Slab Zinc) and shall be at least 
equal to the grade designated as "Prime Western." The 
aluminum content of the bath during actual galvanizing 
operations shall not exceed 0.01%. The galvanizer shall 
not damage the material by overpickling or by the use of 
excessively high temperature in pickling or galvanizing. 

(c) Cement Lined. For cement-lined water heaters, the 
cement shall be applied to provide a minimum thickness 
of ^i 6 in. (5 mm). The lining shall be properly cured, adhere 
firmly to, and completely cover the interior of the vessel. 
The joints at the top of the water heater shall be sealed to 
prevent corrosion in back of the lining. The water absorp- 
tion of the lining material shall not be more than 17% of 
the dry weight of the test specimen. The calcium oxide 
content shall not exceed 35%. The silicon content shall 
not be less than 25%. 

(d) Copper-Lined. The material used for lining may be 
any copper of weldable or brazeable quality with a mini- 
mum thickness of 0.005 in. (0.13 mm). Lining attachments 
to steel backing by welding or brazing shall be in accor- 
dance with Section IX. 



(e) Fluorocarbon Polymer-Lined. Fluorocarbon poly- 
mer linings shall be of an analysis intended for use in 
potable hot water service, and the minimum thickness shall 
be 0.003 in. (0.075 mm). The lining shall be cured at a 
temperature and for a length of time suitable to assure 
continuity of lining and elimination of solvents. The water 
absorption rate of the cured lining shall be less than 2% by 
the method specified in ASTM D 570 shown in Appendix I. 
Surfaces to be fluorocarbon polymer-lined must be cleaned 
to remove all scale, oxidation, oil, etc., prior to application 
of the lining. Interior surfaces may be coated with electro- 
less nickel prior to lining. Flue tubes may be covered with 
a minimum thickness of 0.006 in. (0.15 mm) of sheet 
copper prior to the application of the fluorocarbon polymer 
lining. 

(f) Amine or Polyamine Epoxy-Lined 

(1) Amine or polyamine epoxy linings shall be of an 
analysis intended for use in potable hot water service, and 
the minimum thickness shall be 0.003 in. (0.075 mm). The 
lining shall be cured at a temperature and for a length of 
time suitable to assure continuity of lining and elimination 
of solvents. The water absorption rate of the cured lining 
shall be less than 2% by the method specified in ASTM 
D 570 shown in Appendix I. Surfaces to be epoxy lined 
must be cleaned to remove all scale, oxidation, oil, etc., 
prior to application of the lining. 

(2) The use of amine or polyamine epoxy linings 
shall be limited to electric water heaters with immersion 
type elements, storage tanks, and those surfaces of fired 
water heaters that are not directly heated by the products 
of combustion. 

(g) Thermally Sprayed Metallic Linings. The material 
used for linings shall be any copper or copper alloy of 
sprayable quality. Prior to coating, the interior surfaces of 
the vessel or vessel parts shall be cleaned by grit blasting. 
The minimum lining thickness shall be 0.005 in. (0. 13 mm). 
The process shall be controlled to ensure that the tempera- 
ture of the surface being coated does not exceed 650°F 
(340°C). 

(h) Polymeric, Flexible Linings. Materials used shall 
be listed by National Sanitation Foundation International 
(NSFI) as meeting the requirements of the Standard 
ANSI/NSF 14-1900 for potable water service at a minimum 



139 



2007 SECTION IV 



temperature of 210°F (99°C). The water absorption rate 
of the material shall be less than 10% by the 2 hr boiling 
water immersion test specified in SD-570 shown in Appen- 
dix I. No reground material shall be used. 

The minimum thickness of the lining shall be 0.020 in. 
(0.50 mm). The interior surfaces of the vessel shall be free 
of projections or discontinuities that exceed one-half the 
thickness of the fabricated liner. The installed liner shall 
be in contact with all interior surfaces of the vessel and 
free of folds or cracks after the hydrostatic test of 
HLW-505. The design shall be such that: 

(1) all transition parts, such as needed at vessel open- 
ings, shall be of compatible materials 

(2) transition parts shall be designed so that any 
required brazing or welding of subsequent connections, if 
required, shall not damage the lining 

(i) Autocatalytic (Electroless) Nickel-Phosphorus 
Lined. The composition shall be of an analysis suitable for 
use in potable, hot water service. It shall conform to ASTM 
B 733-90 SC3, Type 1, Class 1. The application shall be 
after all welding. The minimum thickness shall be 0.0003 
in. (0.0075 mm). All surfaces to be lined shall be free of 
oxides, oil or other contaminants. The phosphorus content 
of the bath shall be at least 9%, but not over 13%. Following 
application, the vessel shall be drained and thoroughly 
rinsed with water. 



HLW-201 PRIMARY PRESSURE PARTS 
MATERIAL 

(a) Materials other than those described herein may not 
be used unless approved by the Boiler and Pressure Vessel 
Committee in accordance with Appendix 5 in Section II, 
Part D. The materials used for shells, heads, flues, headers, 
or tubes shall conform to one of the specifications listed 
in Section II and shall be limited to those listed in Tables 
HLW-300, HLW-301, and HF-300.2. For plate material, 
a certificate of compliance or a material test report is 
required to verify that the chemical and mechanical proper- 
ties are within the permissible range listed in Section II. 
Material in all other product forms shall be accepted as 
complying with its Section II specification when marked 
as required by (c) below. Material test reports shall be 
furnished by the mill of origin, except that any material 
that has lost its identification with a Section II specification, 
or that is ordered in small quantities, may be accepted, 
provided that it satisfies the provisions of HLW-202. 

(b) If a welded assembly is furnished as a part to the 
Manufacturer of the completed water heater vessel, a Man- 
ufacturer' s Partial Data Report Form HLW-7 shall be pro- 
vided by the parts Manufacturer. The parts Manufacturer 
shall comply with all applicable requirements of Part HLW, 
including inspection by an Authorized Inspector. 



(c) The material in (a) above shall have the identification 
marking required by the appropriate Section II specifica- 
tion. During subsequent steps in fabrication, a painted color 
identification or some other method acceptable to the 
Authorized Inspector shall be used for identification. The 
method used shall remain distinguishable, or be reapplied 
until the part(s) are affixed in their proper location on the 
water heater vessel, and until the material is part of a 
uniquely identifiable subassembly. 



HLW-202 ACCEPTANCE OF UNIDENTIFIED 
OR SMALL QUANTITIES OF 
MATERIAL 

If the identification of materials required by 
HLW-201 (a) is unavailable, each piece of plate material, 
or each length of other material, shall be shown to meet 
the chemical requirements and mechanical properties of 
the Section II specification designated for the part for which 
the material is to be used. The material shall be subjected 
to all required tests of the Section II specification. The 
manufacturer of the completed vessel shall verify that the 
material complies with the designated specification. 

Testing shall be as in HLW-202. 1 and HLW-202.2. 

HLW-202.1 Plate. The chemical check analysis and 
physical tests shall be made as required in the designated 
specification, with the following modification: when the 
direction of rolling is not definitely known, two tension 
specimens shall be taken at right angles to each other from 
a corner of each plate, and two bend specimens shall be 
taken from the middle of adjacent sides of each plate. One 
tension specimen and both bend specimens shall meet the 
specification requirements. 

HLW-202.2 Tubes, Pipe, Rods, Bars, and Shapes. 

Each length of tube, pipe, rod, bar, or shape shall be sub- 
jected to a chemical check analysis and physical tests to 
show that all the material is identified with a given heat 
or heat treatment lot, and that the material complies with 
the chemical and physical requirements of the designated 
specification. 

HLW-202.3 Marking and Test Report. When the 
identity of material with a designated specification has been 
established in accordance with HLW-202. 1 or HLW-202.2, 
each piece of material (except as alternatively provided in 
the material specification for tubes, pipes, rods, bars, or 
shapes) shall be marked or identified by the manufacturer 
or the testing agency by any method acceptable to the 
Authorized Inspector, giving the designated specification 
number and grade or type, and a serial S-number identi- 
fying the particular lot of material. A suitable test report 
shall be furnished, properly filled out, and certified by the 
manufacturer or testing agency. This report when accepted 



140 



2007 SECTION IV 



by the Authorized Inspector shall constitute authority to 
use the material. 



HLW-203 MISCELLANEOUS PRESSURE PARTS 
MATERIAL 

(a) Parts such as flanges, welding caps, welding necks, 
manhole frames, or manhole covers that are formed by 
casting, forging, rolling, or die forming, shall be con- 
structed from materials permitted under Part HLW, or by 
an appropriate ANSI or manufacturer's standard to which 
the parts are made. Such parts shall be marked with the 
name or trademark of the manufacturer. Such markings 
shall be considered as the manufacturer's certification that 
the product complies with the material specification and 
is suitable for service at the rating indicated. A certificate 
of compliance or a material test report is not required. 

(b) Carbon steel or cast iron pressure parts of small 
size, such as nozzles, internally threaded fittings, handhole 
frames, or handhole covers, for which it is difficult or 
impossible to obtain identified material, or that may be 
stocked and for which material test reports or certificates 
cannot be readily obtained, may be constructed from Sec- 
tion II materials other than those listed in Tables HLW- 
300, HLW-301, and HF-300.2, provided they are suitable 
for the application. These parts may be identified in any 
permanent or temporary manner acceptable to the Author- 
ized Inspector that will serve to identify the parts with the 
manufacturer's written listing. Marking of each individual 
part is not required. The manufacturer who certifies the 
completed vessel shall satisfy himself that such parts are 
suitable for the welding, fabrication, service, and test condi- 
tions of its design. The use of such parts shall be subject 
to the acceptance of the Authorized Inspector. 



HLW-204 FLANGES AND PIPE FITTINGS 

The following standards covering flanges and pipe fit- 
tings are acceptable for use under Part HLW in accordance 
with the requirements of HLW-203. Pressure-temperature 
ratings shall be per the appropriate standard: 

(a) ANSI B16.5, Flanges and Flanged Fittings 

(b) ANSI B16.9, Factory-Made Wrought Steel Butt- 
welding Fittings 

(c) ANSI B16.ll, Forged Steel Fittings, Socket- Weld- 
ing and Threaded 

(d) ANSI B16.15, Cast Bronze Threaded Fittings 

(e) ANSI B 16.24, Bronze Pipe Flanges and Flanged 
Fittings 

(f) ANSI B 16.28, Wrought Steel Buttwelding Short 
Radius Elbows and Returns 

(g) ANSI B 16.42, Ductile Iron Pipe Flanges and 
Flanged Fittings 



HLW-205 NONPRESSURE PART MATERIAL 

Material for nonpressure parts, such as baffles, fins, 
external or internal hangers, supports, or insulating rings, 
need not conform to the specifications for the material 
to which they are attached or to a material specification 
permitted in HLW-300 or HLW-301; but, if welded, they 
shall be of weldable quality. The allowable stress value 
shall not exceed 80% of the maximum allowable stress 
permitted for similar material in Tables HF-300. 1 and 
HF-300.2. Satisfactory performance of a specimen in such 
service shall not make the material acceptable for use in 
pressure parts of a vessel. 



141 



2007 SECTION IV 



ARTICLE 3 
DESIGN 



HLW-300 DESIGN 

(a) Water heaters are limited to a maximum allowable 
working pressure of 160 psi (1 100 kPa) and the maximum 
water temperature shall be 210°F (99°C). The maximum 
allowable working pressure for water heaters shall be not 
less than 100 psi (700 kPa). 

(b) The maximum allowable working pressure of the 
water heater shall be established in accordance with the 
proof test provision of HLW-500. As an alternative, stress 
values in Tables HF-300.2, HLW-300, or HLW-301 may 
be used in calculations employing the available formulas 
when applicable to the geometry of the water heater or 
parts. 

(c) The maximum allowable stress value in bending 
shall be 1 \ times that permitted in tension and the maxi- 
mum allowable stress value in compression shall be two 
times that permitted in tension. 

(d) The temperature used in design shall not be less 
than the mean metal temperature (through the thickness) 
expected under operating conditions for the part consid- 
ered. If necessary, the metal temperature shall be deter- 
mined by computation using accepted heat transfer 
procedures or by measurements from equipment in service 
under equivalent operating conditions. Pressure parts sub- 
ject to direct radiation and /or the products of combustion 
shall be designed to prevent flame impingement. 

(e) Water heaters may be fired with oil, gas, or elec- 
tricity. 

(f) Water heaters and tanks built under the rules of 
Part HLW may be provided with cathodic protection. 

(g) Water heaters used for deionized water fabricated 
of stainless steel listed in Table HLW-301 may be built to 
Part HLW provided the maximum thickness does not 
exceed \ in. (13 mm). 



HLW-301 BASIS FOR ESTABLISHING 
STRESS VALUES IN TABLES 
HLW-300 AND HLW-301 

In the determination of allowable stress values for pres- 
sure parts, the Committee is guided by successful experi- 
ence in service, insofar as evidence of satisfactory 
performance is available. Such evidence is considered 



equivalent to test data where operating conditions are 
known with reasonable certainty. In the evaluation of new 
materials, it is necessary to be guided to a certain extent 
by the comparison of test information with similar data on 
successful applications of similar materials. 

At any temperature below the creep range, the allowable 
stresses are established at no higher than the lowest of the 
following: 

(1) \ of the specified minimum tensile strength at 
room temperature 

(2) l / 4 of the tensile strength at temperature 

(3) % of the specified minimum yield strength at room 
temperature 

(4) % of the yield strength at temperature 

In Table HLW-301 for austenitic stainless steel materi- 
als, two sets of allowable stress values are provided. The 
higher values should be used only where slightly greater 
deformation is not in itself objectionable. The higher alter- 
native allowable stresses are identified by a note. These 
stresses exceed two-thirds for austenitic stainless steel 
materials but do not exceed 90% of the minimum yield at 
temperature. These higher stresses are not recommended 
for the design of flanges and other strain sensitive applica- 
tions. 



HLW-302 MINIMUM THICKNESSES 

The minimum thickness of sheet or plate material used 
for heads or shells in any lined or unlined water heater 
vessel shall not be less than \ in. (3 mm). 



HLW-303 SHELLS UNDER INTERNAL 
PRESSURE 

When the provisions of HLW-501 to HLW-504 are not 
used, the thickness and the maximum allowable working 
pressure of cylindrical shells, pipe, and headers shall be 
determined in accordance with the following formulas: 



t = 



PR 



SE - 0.6P 



P = 



SEt 



R + 0.6r 



142 



2007 SECTION IV 



Spec. 
No. 



TABLE HLW-300 
MAXIMUM ALLOWABLE STRESS VALUES IN TENSION FOR LINED MATERIALS, ksi (MPa) 



Grade 







External 


Spec. Min. 


Spec. Min. 




Max. Allow. 


Nominal 




Group Pressure 


Tensile Strength, 


Yield Strength, 




Stress Value, 


Composition 


P-No. 


No. Chart 


ksi (MPa) 


ksi (MPa) 


Note(s) 


ksi (MPa) 



07 



Plate 

SA-36 
SA-285 



SA-455 
SA-455 
SA-455 

SA-285 Modified to Chem. 
AISI C-1012 
AISI C-1015d 
AISI C-1023 



SA-515 



SA-516 



60 
65 
70 

55 
60 
65 
70 



Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 

Carbon steel 
Carbon steel 
Carbon steel 

0.10C to 0.15C 
0.13C to 0.18C 
0.20C to 0.25C 

Carbon steel 
Carbon steel 
Carbon steel 

Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 



CS-2 
CS-2 
CS-2 

CS-2 
CS-2 
CS-2 
CS-2 



58.0 (400) 
45.0 (310) 
50.0 (345) 
55.0 (380) 

75.0 (515) 
73.0 (505) 
70.0 (485) 

45.0 (310) 
50.0 (345) 
55.0 (380) 

60.0 (415) 
65.0 (450) 
70.0 (485) 

55.0 (380) 
60.0 (415) 
65.0 (450) 
70.0 (485) 



(1) 



(2) 
(3) 
(4) 

(5) 



32.0 (220) 
35.0 (240) 
38.0 (260) 

30.0 (205) 
32.0 (220) 
35.0 (240) 
38.0 (260) 



14.5 (100.0) 
11.3 (77.6) 
12.5 (86.2) 
13.8 (94.8) 

18.8 (129.0) 
18.3 (126.0) 
17.5 (121.0) 

11.3 (77.6) 
12.5 (86.2) 
13.8 (94.8) 

15.0 (103.0) 
16.3 (112.0) 
17.5 (121.0) 

13.8 (94.8) 
15.0 (103.0) 
16.3 (112.0) 
17.5 (121.0) 



Sheet 

SA-414 A 

B 
C 
D 
E 
F 
G 

SA-414 Modified to Chem. 
AISI C-1012 
AISI C-1015 
AISI C-1023 



Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 
Carbon steel 

0.10C to 0.15C 
0.13C to 0.18C 
0.20C to 0.25C 



45.0 (310) 
50.0 (345) 
55.0 (380) 
60.0 (415) 
65.0 (450) 
70.0 (485) 
75.0 (515) 

45.0 (310) 
50.0 (345) 
55.0 (380) 



(5) 



11.3 (77.6) 
12.5 (86.2) 
13.8 (94.8) 
15.0 (103.0) 
16.3 (112.0) 
17.5 (121.0) 
18.8 (129.0) 



11.3 (77.6) 
12.5 (86.2) 
13.8 (94.8) 



Forging(s) 

SA-105 
SA-181 
SA-181 

Pipe 

SA-53 
SA-53 
SA-106 



Forging carbon steel 1 
Class 60 Forging carbon steel 1 
Class 70 Forging carbon steel 1 



A 


Smls. carbon steel 


1 


1 


B 


Smls. carbon steel 


1 


1 


A 


Smls. carbon steel 


1 


1 



70.0 (485) 
60.0 (415) 
70.0 (485) 



48.0 (330) 
60.0 (415) 
48.0 (330) 



17.5 (121.0) 
15.0 (103.0) 
17.5 (120.7) 



12.0 (82.7) 
15.0 (103.0) 
12.0 (82.7) 



143 



2007 SECTION IV 



TABLE HLW-300 
MAXIMUM ALLOWABLE STRESS VALUES IN TENSION FOR LINED MATERIALS, ksi (MPa) (CONT'D) 



Spec. 
No. 



Grade 



Nominal 
Composition 



P-No. 



External Spec. Min. Spec. Min. 

Group Pressure Tensile Strength, Yield Strength, 
No. Chart ksi (MPa) ksi (MPa) 



Note(s) 



Max. Allow. 

Stress Value, 

ksi (MPa) 



SA-106 


B 


Smls. carbon steel 


1 


1 


SA-106 


C 


Smls. carbon steel 


1 


2 


SA-53 


A 


ERW carbon steel 


1 


1 


SA-53 


B 


ERW carbon steel 


1 


1 


SA-135 


A 


ERW carbon steel 


1 


1 


SA-135 


B 


ERW carbon steel 


1 


1 



60.0 (415) 
70.0 (485) 

48.0 (330) 
60.0 (415) 

48.0 (330) 
60.0 (415) 





15.0 (103.0) 




17.5 (121.0) 


(6) 


10.2 (70.3) 


(6) 


12.8 (87.9) 


(6) 


10.2 (70.3) 


(6) 


12.8 (87.9) 



Tube 

SA-178 
SA-178 

SA-513 
SA-513 
SA-513 



ERW carbon steel 
ERW carbon steel 



1008 ERW carbon steel 
1010 ERW carbon steel 
1015 ERW carbon steel 



47.0 (325) 
60.0 (415) 

42.0 (290) 
45.0 (310) 
48.0 (330) 



(6)(7) 


10.0 (68.9) 


(6) 


12.8 (87.9) 


(6)(7)(8) 


8.9 (61.5) 


(6)(7)(8) 


9.6 (65.9) 


(6)(7)(8) 


10.2 (70.3) 



Bars 



SA-36 




Carbon steel 


1 


1 


SA-675 


45 


Carbon steel 


1 


1 




50 


Carbon steel 


1 


1 




55 


Carbon steel 


1 


1 




60 


Carbon steel 


1 


1 




65 


Carbon steel 


1 


1 




70 


Carbon steel 


1 


2 



58.0 (400) 
45.0 (310) 
50.0 (345) 
55.0 (380) 
60.0 (415) 
65.0 (450) 
70.0 (485) 



(9)(1) 



14.5 (100.0) 
11.3 (77.6) 
12.5 (86.2) 
13.8 (94.8) 
15.0 (103.0) 
16.3 (112.0) 
17.5 (121.0) 



GENERAL NOTES: 

(a) Nonferrous material, if utilized for connections, etc., shall be in accordance with Table HF-300.2. 

(b) To convert from ksi to MPa, multiply by 6.895. 

NOTES: 

(1) SA/CSA-G40.21, as specified in Section II, Part A, grade 38W or 44W may be used in lieu of SA-36 for plates and bars not exceeding % in. 
(19 mm) for use at the same maximum allowable stress values as SA-36. 

(2) For thickness up to % in. (10 mm), incl. 

(3) For thickness over % in. to 0.580 in. (10 mm to 15 mm), incl. 

(4) For thickness over 0.580 in. to 0.750 in. (15 mm to 19 mm), incl. 

(5) For use only as shell plates, heads, tubesheets, or other surfaces to be glass lined. 

(6) The stress value includes a joint factor of 0.85. 

(7) Tensile value is expected minimum. 

(8) This tube is restricted to use in glass lined water heaters. 

(9) These allowable stress values apply also to structural shapes. 



144 



2007 SECTION IV 



TABLE HLW-301 
MAXIMUM ALLOWABLE STRESS VALUES FOR MATERIALS IN TENSION FOR UNLINED WATER HEATERS, 

ksi (MPa) 

Max. Allowable 

Design Stress, ksi (MPa) 

(See HLW-303) 



Spec. 


Nominal 


No. Grade 


Compositior 


Plate 




Alloy Steel 




SA-240 304 


18Cr-8Ni 


304L 


18Cr-8Ni 


316 


16Cr-12Ni-2Mo 


316L 


16Cr-12Ni-2Mo 


439 


18Cr-Ti 


S44400 


18Cr-2Mo 


Tube 




Alloy Steel 







Spec. 


Spec. 




Min. 


Min. 




Tensile 


Yield 


External 


Strength, 


Strength, 


Group Pressure 


ksi 


ksi 


P-No. No. Chart 


(MPa) 


(MPa) 



Note(s) 



Standard 



Alternative 
[See Note (8)] 



8 


1 


HA-1 


75.0 (515) 


30.0 (205) 


(1)(2)(3) 


16.7 (114.0) 


17.8 (122.0) 


8 


1 


HA-3 


70.0 (485) 


25.0 (170) 


(1)(2)(3) 


14.3 (98.4) 


16.5 (114.0) 


8 


1 


HA-2 


75.0 (515) 


30.0 (205) 


(1)(2)(3) 


17.7 (119.0) 


18.8 (129.0) 


8 


1 


HA-4 


70.0 (485) 


25.0 (170) 


(1)(2)(3) 


14.1 (97.8) 


16.7 (115.0) 


7 


2 




60.0 (415) 


30.0 (205) 


(4)(2)(5) 


16.3 (103.0) 




7 


2 


CS-2 


60.0 (415) 


40.0 (275) 


(4)(1)(5) 


15.0 (103.0) 





SA-213 TP304 Smls. 18Cr-8Ni 

TP304L Smls. 18Cr-8l\li 

TP316 Smls. 16Cr-12Ni-2Mo 

TP316L Smls. 16Cr-12l\li-2Mo 

SA-249 TP304 Wld. 18Cr-8Ni 

TP304L Wld. 18Cr-8l\li 

TP316 Wld. 16Cr-12Ni-2Mo 

TP316L Wld. 16Cr-12Ni-2Mo 

SA-268 TP439 Smls. 18Cr-Ti 

S44400 Smls. 18Cr-2Mo 

S44400 Wld. 18O-2M0 

S44735 Smls. 29Cr-4Mo 

S44735 Wld. 29Cr-4Mo 



8 


1 


HA-1 


75.0 (515) 


30.0 (205) 


8 


1 


HA-3 


70.0 (485) 


25.0 (170) 


8 


1 


HA-2 


75.0 (515) 


30.0 (205) 


8 


1 


HA-4 


70.0 (485) 


25.0 (170) 


8 


1 


HA-1 


75.0 (515) 


30.0 (205) 


8 


1 


HA-3 


70.0 (485) 


25.0 (170) 


8 


1 


HA-2 


75.0 (515) 


30.0 (205) 


8 


1 


HA-4 


70.0 (485) 


25.0 (170) 


7 


2 


CS-2 


60.0 (415) 


30.0 (205) 


7 


2 


CS-2 


60.0 (415) 


40.0 (275) 


7 


2 


CS-2 


60.0 (415) 


40.0 (275) 


10J 


1 


CS-2 


75.0 (515) 


60.0 (415) 


10J 


1 


CS-2 


75.0 (515) 


60.0 (415) 



(1)(2)(3) 16.7 (114.0) 17.8 (122.0) 

(1)(2)(3) 14.3 (98.4) 16.5 (114.0) 

(1)(2)(3) 17.7 (119.0) 18.8 (129.0) 

(1)(2)(3) 14.1 (97.8) 16.7 (115.0) 

(1)(2)(3)(6) 14.2 (97.1) 15.1 (104.0) 

(1)(2)(3)(6) 11.9 (83.6) 14.0 (96.8) 

(1)(2)(3)(6) 15.0 (101.0) 16.0 (110.0) 

(1)(2)(3)(6) 12.0 (83.1) 14.2 (97.7) 

(4)(2)(5) 15.0 (103.0) 

(4)(1)(5) 15.0 (103.0) 

(4)(1)(5)(3)(6) 12.8 (88.3) 

(7) 18.4 (127.0) 

(6)(7) 15.5 (107.0) 



Bar 




Alloy Steel 




SA-479 304 


18Cr-8Ni 


304L 


18Cr-8Ni 


316 


16Cr-12Ni-2Mo 


316L 


16Cr-12Ni-2Mo 



439 



18Cr-Ti 



S44400 18Cr-2Mo 



8 


1 


75.0 (515) 


8 


1 


70.0 (485) 


8 


1 


75.0 (515) 


8 


1 


70.0 (485) 


7 


2 


70.0 (485) 


7 


2 


60.0 (415) 



(1)(2)(3) 
(1)(2)(3) 
(1)(2)(3) 
(1)(2)(3) 
(4)(2)(5) 
(4)(1)(5) 



16.7 (114.0) 
14.3 (98.4) 
17.7 (119.0) 
14.1 (97.8) 
16.6 (114.0) 
15.0 (103.0) 



17.8 (122.0) 
16.5 (114.0) 
18.8 (129.0) 
16.7 (115.0) 



Pipe 
Alloy Steel 

SA-312 TP304 Smls. 18Cr-8l\li 

TP304 Wld. 18Cr-8Ni 

TP304L Smls. 18Cr-8l\li 

TP304L Wld. 18Cr-8l\li 



1 


HA-1 


75.0 (515) 


30.0 (205) 


(1)(2)(3) 


16.7 (114.0) 


17.8 (122.0) 


1 


HA-1 


75.0 (515) 


30.0 (205) 


(1)(2)(3)(6) 


14.2 


15.1 (98.0) 


1 


HA-3 


70.0 (485) 


25.0 (170) 


(1)(2)(3) 


14.3 (98.4) 


16.5 (114.0) 


1 


HA-3 


70.0 (485) 


25.0 (170) 


(1)(2)(3)(6) 


12.2 


14.0 (0.0) 



145 



2007 SECTION IV 



TABLE HLW-301 
MAXIMUM ALLOWABLE STRESS VALUES FOR MATERIALS IN TENSION FOR UNLINED WATER HEATERS, 

ksi (MPaKCONT'D) 

Max. Allowable 

Design Stress, ksi (MPa) 

(See HLW-303) 



Spec. 
No. 



Grade 



Nominal 
Composition 



P-No. 





Spec. 


Spec. 




Min. 


Min. 


External 


Tensile 


Yield 


Group Pressure 


Strength, 


Strength, 


No. Chart 


ksi (MPa) 


ksi (MPa) 



Note(s) 



Standard 



Alternative 
[See Note (8)] 



Pipe 
Alloy Steel 

SA-312 TP316 Smls. 16Cr-12Ni-2Mo 

TP316 Wld. 16Cr-12l\li-2Mo 

TP316L Smls. 16Cr-12l\li-2Mo 

TP316L Wld. 16Cr-12l\li-2Mo 

Forgings 
Alloy Steel 

SA-182 F304 18Cr-8Ni 

F304L 18Cr-8Ni 

F316 16Cr-12Ni-2Mo 

F316L 16Cr-12Ni-2Mo 



HA-2 75.0 (515) 

HA-2 75.0 (515) 

HA-4 70.0 (485) 

HA-4 70.0 (485) 



30.0 (205) 
30.0 (205) 
25.0 (170) 
25.0 (170) 



HA-1 75.0 (515) 30.0 (205) 

HA-3 70.0 (485) 25.0 (170) 

HA-2 75.0 (515) 30.0 (205) 

HA-4 70.0 (485) 25.0 (170) 



(1)(2)(3) 
(1)(2)(3)(6) 

(1)(2)(3) 
(1)(2)(3)(6) 



(1)(2)(3) 
(1)(2)(3) 
(1)(2)(3) 
(1)(2)(3) 



17.7 (119.0) 18.8 (129.0) 

15.0 (84.0) 16.0 (83.0) 

14.1 (97.8) 16.7 (115.0) 
12.0 (83.1) 14.2 (0.0) 



16.7 (114.0) 17.8 (122.0) 

14.3 (98.4) 16.5 (114.0) 

17.7 (119.0) 18.8 (129.0) 

14.1 (97.8) 16.7 (115.0) 



GENERAL NOTE: To convert from ksi to MPa, multiply by 6.895. 

NOTES: 

(1) The maximum thickness is \ in. (12.7 mm). 

(2) The service temperature shall not exceed 210°F (99°C). 

(3) Water heaters using this material are to be operated only on deionized water having a minimum specific resistivity of 1.0 M/^cm. 

(4) The maximum is % in. (10 mm). 

(5) Filler metal shall be Type 430 with a nominal molybdenum content of approximately 2%. The 300 series of chromium-nickel-iron filler 
metals shall not be used in welding vessels conforming to the requirements of Section IV. 

(6) The stress value includes a joint factor of 0.85. 

(7) Heat treatment after forming or fabrication is neither required nor prohibited. 

(8) Due to the relatively low yield strength of the austenitic stainless steel materials, these higher stress values were established at temperatures 
at which the short time tensile properties govern to permit the use of these alloys where slightly greater deformation is acceptable. These 
higher stress values exceed two-thirds but do not exceed 90% of the yield strength at temperature. Use of these stress values may result in 
dimensional changes due to permanent strain. These stress values are not recommended for flanges of gasketed joints or other applications 
where slight amounts of distortion can cause leakage or malfunction. 



where 

E = efficiency of longitudinal joint or ligament 
between tube holes, whichever is less. For welded 
joints, use the efficiency specified in HLW-402. 
For seamless shells, use E = 1. 

P = maximum allowable working pressure, psi (kPa) 
(but not less than 100 psi) 

R = inside radius of cylinder, in. (mm) 

5 = maximum allowable stress value from Tables 
HLW-300, HLW-301, HF-300.1, and HF-300.2, 
psi (MPa) 
t = required wall thickness, exclusive of liner, in. 

HLW-305 BLANK UNSTAYED DISHED HEADS, 
PRESSURE ON CONCAVE SIDE 
HLW-305. 1 General. When the provisions of 
HLW-501 to HLW-504 are not used, the required thickness 



at the thinnest point after forming of ellipsoidal and torisph- 
erical heads underpressure on the concave side (plus heads) 
shall be computed by the appropriate formulas in this para- 
graph. 

(a) Notations. The notations used in this paragraph are 
defined as follows: 

D = inside diameter of the head skirt; or inside length 
of the major axis of an ellipsoidal head; or inside 
diameter of a cone head at the point under consid- 
eration, measured perpendicular to the longitudi- 
nal axis, in. (mm) 

E = lowest efficiency of any joint in the head; use the 
efficiency specified in HLW-402. For seamless 
heads, use E = 1. 

L = inside spherical or crown radius, in. (mm) 

P = maximum allowable working pressure, psi (kPa) 
[but not less than 100 psi (700 kPa)] 



146 



2007 SECTION IV 



S = maximum allowable stress value from Tables 
HLW-300, HF-300.1, and HF-300.2, psi (MPa) 

t = required wall thickness, exclusive of liner, in. 
(mm) 

HLW-305.2 Ellipsoidal Heads. When the provisions 
of HLW-501 to HLW-504 are not used, the required thick- 
ness and the maximum allowable working pressure of a 
dished head of semiellipsoidal form, in which half the 
minor axis (inside depth of the head minus the skirt) equals 
one-fourth of the inside diameter of the head skirt, shall 
be calculated by the following formulas: 



t = 



PD 



2SE - 0.2P 



2SEt 



D + Q.2t 



HLW-305.3 Torispherical Heads. When the pro- 
visions of HLW-501 to HLW-504 are not used, the required 
thickness and the maximum allowable working pressure 
of a torispherical head shall be calculated by the following 
formulas: 



t = 



P = 



0.885PL 
SE - 0.1P 

SEt 
0.885L + O.lt 



HLW-305.4 Inside Crown Radius of Unstayed 
Heads. The inside crown radius to which an unstayed 
formed head is dished shall be not greater than the outside 
diameter of the skirt of the head. The inside knuckle radius 
of a torispherical head shall be not less than 6% of the 
outside diameter of the skirt of the head but in no case 
less than three times the head thickness. 

HLW-305.5 Hemispherical Heads. Because of the 
complexity of joint design, hemispherical heads are not 
permitted. 



HLW-306 BLANK UNSTAYED DISHED HEADS, 
PRESSURE ON CONVEX SD3E 

HLW-306.1 When the provisions of HLW-501 to 
HLW-504 are not used, unstayed dished heads with the 



pressure on the convex side shall have a maximum allow- 
able working pressure equal to 60% of that for heads of 
the same dimension with the pressure on the concave side. 

HLW-306.2 Hemispherical Heads. Because of the 
complexity of joint design, hemispherical heads are not 
permitted. 



HLW-307 TUBES 

When the provisions of HLW-501 to HLW-504 are not 
used, the thickness of seamless or welded tubes shall be 
in accordance with HG-301.2 when subjected to internal 
pressure or HG-312.2 when subjected to external pressure. 



HLW-308 OPENINGS 

HLW-308.1 Single openings in water heaters do not 
require reinforcement under the following conditions. 
Welded connections attached in accordance with the appli- 
cable rules and not larger than 

(a) NPS 3 (DN 80) in shells or heads % in. (10 mm) or 
less; NPS 2 (DN 50) in shells or heads over % in. (10 mm) 

(b) threaded, studded, or expanded connections in which 
the hole cut in the shell or head is not greater than NPS 2 
(DN 50) 

HLW-308.2 When the provisions of HLW-501 to 
HLW-504 are not used, all other openings shall be rein- 
forced in accordance with HG-321 of this Section. 



HLW-309 TUBES ATTACHED BY ROLLING 

(a) The tube hole in the head or tubesheet shall be 
formed either: 

(1) to the full size diameter by a method that will 
not produce irregularities that would interfere with proper 
rolling and sealing, or 

(2) to a lesser diameter, then enlarged to full diameter 
by a secondary drilling, cutting, or reaming operation to 
remove such irregularities. 

The sharp edges of tube holes shall be taken off both 
sides with a file or other tool. 

(b) The minimum thickness of any tubesheet with tubes 
installed by rolling shall be 3 / l6 in. (5 mm). 



147 



2007 SECTION IV 



ARTICLE 4 
DESIGN OF WELDMENTS 



HLW-400 DESIGN OF WELDED JOINTS 

HLW-401 GENERAL REQUIREMENTS 

All welds, fillet or full penetration, shall be made to a 
qualified welding procedure by qualified welders for each 
welding process employed (manual, semiautomatic, auto- 
matic), in accordance with the applicable provisions of 
Section IX to insure satisfactory penetration and fusion 
into the base metal to the root of the weld. It should be 
noted that the use of standard welding procedures is accept- 
able. All requirements for the use of these procedures 
shall be in accordance with Section IX. The use of these 
procedures shall be addressed in the manufacturer's or 
contractor's Quality Control Manual and shall be available 
for review by the Authorized Inspector. All members, prior 
to being welded, shall be properly fitted, aligned, and 
retained in position in accordance with the Procedure Spec- 
ification for the welding procedure to be used. 

HLW-401.1 Butt Joints. Longitudinal or circumferen- 
tial joints uniting plates of a drum, shell, or other pressure 
parts shall be butt joints. A butt joint shall be double welded 
butt or may have filler metal added from one side only, 
provided the weld penetration is complete. 

(a) If there are two or more courses, the welded longitu- 
dinal joints of adjacent courses shall be not less than 6 in. 
(150 mm) apart. 

(b) If the plates are of unequal thickness, at no point 
shall the plate on one side of the joint be offset with the 
plate on the other side of the joint in excess of one-fourth 
of the thickness of the thickest plate. The weld may be 
partly or entirely in the tapered section or adjacent to it as 
indicated in Fig. HLW-401.1. 

HLW-401.2 Corner or Tee Joints. Unflanged heads or 
tubesheets of water heaters may be constructed by attaching 
unflanged heads or tubesheets to the shell by welding, 
provided 

(a) corner or tee joints shall be as shown in Fig. HLW- 
401. 2, sketches (a), (b), (c), (d), or (e). 

(b) the head or tubesheet is supported by tubes. 

(c) the welded joint for Fig. HLW-401.2, sketches (a), 
(b), and (c) is wholly within the shell and forms no part 
thereof. The throat of the fillet weld shall be not less than 
0.7 times the thickness of the thinner plate. 



FIG. HLW-401.1 BUTT WELDING OF PLATES OF 
UNEQUAL THICKNESS 




Tapered one 
side only 
(inside or 
outside) 




(a) 


(b) 


(c) 


Preferred Method 


Permissible 


Not 


(Center lines 


(Circumferential 


Permissible 


coincide) 


joints only) 





(d) for Fig. HLW-401.2, sketches (b) and (d), the weld 
shall have full penetration, and for sketch (e), double full- 
fillet welds shall be provided. 



HLW-402 JOINT EFFICIENCIES 

The following joint efficiencies E are to be used in the 
formulas of this Section (i.e., HLW-303 and HLW-305) 
for joints completed by an arc or gas welding process. 

(a) E = 85% for full penetration butt joints as attained 
by double welding or by other means, which will obtain 
the same quality of deposited weld metal on the inside and 
outside weld surfaces, to provide complete joint penetration 
and assurance that the weld grooves are completely filled 
(HLW-401.1). Welds that use metal backing strips that 
remain in place are excluded. 

(b) E = 80% for full penetration single-welded butt 
joints with backing strips other than those included in (a) 
above. 



07 



148 



2007 SECTION IV 



FIG. HLW-401.2 TYPICAL CORNER JOINTS 

Not less than 1.25r s 
but need not be greater than f/, 



^ 



'/!- 



f c min. 



c 



(a) Required 



WT 



th 



c,' 



f c mm. 



£1 



\ 



Backing 
strip may 
be used 



th- 



(b) Required 



Not 
welded 



(c) Required 



2t e min. 




Backing 
strip may 
be used 



(d) Required 



? 


\, 




1 




*— f/, 



St + s 2 = 2t m where 
St is not less 
than 0.5 nor 
greater than 2s 2 



(e) Required 



(f) Not Permissible 



t s = nominal shell thickness 
t h = nominal head thickness 



HLW-402.1 Joint Efficiencies for External Pressure 
Design. Joint efficiency E factors are not required to be 
used when the part is designed for external pressure only. 

HLW-411 HEADS OR TUBESHEETS 
ATTACHED BY WELDING 

Typical water heater welded joints are shown in 
Fig. HLW-411. 

HLW-411.1 Flanged heads or tubesheets of water heat- 
ers attached by butt welding shall be in accordance with 
Fig. HLW-415, sketch (d) or (e). 

HLW-411.2 Flanged heads or tubesheets of water heat- 
ers may be constructed by attaching an outwardly or 
inwardly flanged head or tubesheet to the shell by fillet 
welding, provided 



(a) inwardly flanged head or tubesheets are full fillet 
welded [see Fig. HLW-415, sketch (a)] 

(b) the joint attaching an outwardly flanged head or 
tubesheet shall be in accordance with Fig. HLW-415, 
sketch (b) or (c) 



HLW-413 TUBES ATTACHED BY WELDING 

(a) The edge of the plate at the tubesheet hole may be 
beveled or recessed to a depth at least equal to the thickness 
of the tubes. Where the plate is beveled or recessed, the 
projection of the tubes beyond the tube sheet shall not 
exceed a distance equal to the tube thickness. The depth 
of any bevel or recess shall not be less than the tube 
thickness or % in. (3 mm), whichever is greater, nor more 
than one-third of the tubesheet thickness. 



149 



2007 SECTION IV 



FIG. HLW-411 TYPICAL WATER HEATER WELDED JOINTS 



See Fig. 
HLW-415(d) 



See Fig. 
HLW-415(a) 




See Fig. 
HLW-413(b) 



See Fig. 
HLW-415(c) 



See Fig. 

413(c) 



See Fig 
HLW-415(e) 



See Fig 
HLW-415(d) 



See Fig. 
HLW-415(c) 



(a) Unstayed, Flanged, and 
Dished Heads 




See Fig. 
HLW-415(a) 



See Fig. 
HLW-413(e) 



See Fig. 
HLW-413(a) 



See Fig. 
HLW-415(b) 



(b) Flanged and Dished Heads 
With Flue Tube 



(b) Where no bevel or recess is employed, tubes shall 
extend beyond the tubesheet not less than 1.5 times the 
tube thickness, nor more than 3 times the sum of the 
thickness of the head plus the thickness of the tube [see 
Fig. HLW-413, sketch (d)]. 

(c) When openings are flanged for tubes as shown in 
Fig. HLW-413, sketch (a), (b), or (e), flanges shall extend 
parallel to the tube for a minimum distance equal to the 
tube thickness. 

(d) Where exposed to gases of greater than 850°F 
(450°C), head flanges shall conform to the limitations of 
Fig. HLW-413. 

(e) When the temperature of the gases is normally 850°F 
(450°C) or less, the length of flange or tube may extend 
beyond the limits of Fig. HLW-413. 



HLW-415 HEAD-TO-SHELL ATTACHMENTS 

Ellipsoidal, torispherical, and other types of formed 
heads, concave or convex to the pressure shall have the 
following requirements as to skirt length. 

(a) An ellipsoidal or torispherical head that is attached 
to a shell by a butt joint as shown in Fig. HLW-415, sketch 



(e), need not be provided with a skirt when the nominal 
head thickness does not exceed 1 V 4 times the nominal shell 
thickness. When the nominal head thickness exceeds 1% 
times the nominal shell thickness, a skirt shall be provided 
having a length not less than 3 times the nominal head 
thickness or \V 2 in. (38 mm), whichever is smaller. When 
a skirt is used, it shall meet the requirements for shell 
thickness in HLW-301. 

(b) Ellipsoidal or torispherical heads, concave or convex 
to pressure, that are to be fitted inside or over a shell (lap 
joint) shall have a skirt of at least 3 times the nominal 
head thickness, but in no case less than 1 in. (25 mm). 

(c) Shells and heads may be attached to shells or heads 
using a butt weld with one plate edge offset as shown in 
Fig. HLW-415, sketch (d). The weld may be deposited on 
the inside of the vessel only when the weld is accessible 
for inspection after the vessel is completed. 



HLW-420 OPENINGS IN WELDS 

Any type of opening that meets the requirements for 
reinforcement given in HG-321 may be located in a butt 
welded joint. 



150 



2007 SECTION IV 



FIG. HLW-411 TYPICAL WATER HEATER WELDED JOINTS (CONT'D) 



See Fig. HLW-413 (d) 
See Fig. HLW-401.2 (a) 



See Fig. HLW-401.2 (c) 
See Fig. HLW-413 (d)- 




See Fig. HLW-413 (a) 
See Fig. HLW-413 (b) 
See Fig. HLW-413 (c) 
SeeFig. HLW-4 15(b) 



See Fig. HLW-415 (c) 
See Fig. HLW-413 (c) 

See Fig. HLW-413 (b) 

See Fig. HLW-413 (a) 



(c) Unflanged and flanged flat heads with multiple heads 



151 



2007 SECTION IV 



FIG. HLW-413 TUBES ATTACHED BY WELDING 




f* mm. 



(a) 



t t min. but may not 
exceed 3(fy + f f ) 
[see HLW-4 13(c)] 



K 




Si 



1 1 



tf. min. 



(b) 



vh 




May not exceed 
3(t h + t t ) 



May not exceed 
3(f„ + t f ) 
[see HLW-413(c)] 



(c) 



K 



SI 



rft 



1 1.5f f min. but may 
not exceed 3(f/, + t t ) 



f* min. — *\ 



(d) 




(e) 



_t 



May not exceed 
3(t h + t t ) 
[see HLW-4 13(c)] 



t f - nominal tube thickness 



tft = nominal head thickness 



152 



2007 SECTION IV 



FIG. HLW-415 HEADS ATTACHED TO SHELLS 



0.7f c min 




,J 



2t h min. but 
not less than V2 in. (13 mm) 

Tangent line 

1.3f c min. 



=£* 



■* — 3t h min. but not 

less than 1 in. (25 mm) 

(a) 



0.7f c min. 



r 




7 



' 2f s min. 
1.3f Q min. 



3t h min. but not 
less than 1 in. (25 mm) 



(b) 



Tangent 
line — 



'*! 



3t h min. 
but need 
not exceed 1 in. (25 mm) 



*A /H 



I*= 



Taper optional 



r 



U mm. 



h — 1.3f s min. 
h— 2f s min. 



(c) 



(a), (b) and (c) Single Fillet 
Lap weld 



- — Skirt optional 
-* — Tangent line 



l A 



U 






When t h is equal to or 
less than 1.25f c 



" — 3t h min. but 

need not exceed 1 in. (25 mm) 



Bevel 
optional 




Tangent line 



See also 
Fig. HLW-401.1 



When t h exceeds 1.25f s 
(e) Butt Weld 



As desired 



2 1 / 2 fmax. 
1f min. 




Avoid sharp 
break 

Depth of offset = f •, 



lV2f min. 
for f, = 5 / 8 in. (16 mm) max. 



(d) Butt Weld With One 
Plate Edge Offset 



r fs r 



r^v 



(f) (g) 

Details (f), (g), and (h) are 
not permissible. 



f s = Nominal shell thickness 
t h = Nominal head thickness 



-K 



(h) 



153 



2007 SECTION IV 



HLW-430 WELDED CONNECTIONS 

HLW-430.1 Strength of Attachment Welds. Nozzles, 
other connections, and their reinforcement may be attached 
to a water heater by arc or gas welding. Sufficient welding 
shall be provided on either side of the line through the 
center of the opening parallel to the longitudinal axis of 
the shell to develop the strength of the shell as prescribed 
in HG-327 through shear or tension in the weld, whichever 
is applicable. The strength of groove welds shall be based 
on the area subjected to shear or to tension. The strength 
of fillet welds shall be based on the area subjected to 
shear, computed on the minimum leg dimension. The inside 
periphery of a fillet weld shall be used in computing its 
length. 

HLW-430.2 Stress Values for Weld Metal. The allow- 
able stress values for groove and fillet welds and for shear 
in nozzle necks in percentages of stress values for the 
vessel material are as follows: 



Factor 



Percentage of Stress Values, % 



Nozzle wall 


70 


Grooveweld tension 


74 


Groove weld shear 


60 


Fillet weld shear 


49 



NOTE: These values are obtained by combining the following factors: 
87^% for combined end and side loading, 80% for shear strength, and 
the applicable joint efficiency factors. 



HLW-431 MINIMUM REQUIREMENTS FOR 
ATTACHMENT WELDS 

HLW-431.1 General. The location and minimum size 
of attachment welds for nozzles and other connections shall 
conform to the requirements in this paragraph. 

(a) Notations. The notations used in this paragraph and 
in Fig. HLW-431.1 are defined as follows: 

t = nominal thickness of shell or head 
t c = the smaller of % in. (6 mm) or 0.1t n (inside 
corner welds may be further limited by a lesser 
length of projection of the nozzle wall beyond 
the inside face of the water heater wall) 
t e = thickness of reinforcement element 
?mi n = the smaller of 3 / 4 in. (19 mm) or the thickness 
of either of the parts joined by a fillet, single- 
bevel, or single-J weld, in. (mm) 
t n = nominal thickness of nozzle wall 
t w = dimension of partial-penetration attachment 
welds (fillet, single-bevel, or single-J), mea- 
sured as shown in Fig. HLW-431.1 
t h t 2 = not less than V 3 t min or V 4 in. (6 mm) and t\ + 
t 2 not less than 1 l / 4 t ^n 



HLW-431.2 Inserted Nozzles Without Added Rein- 
forcement Elements 

(a) Nozzles inserted into or through a hole cut in the 
shell and without additional reinforcement elements shall 
be attached by a full-penetration groove weld or by two 
partial penetration welds, one on each face of the shell. 
Permissible types of welds are shown in Fig. HLW-431.1, 
sketches (a) through (h). 

(b) Backing strips shall be used with full penetration 
welds deposited from one side only when the shell thick- 
ness is over 3 / 8 in. (10 mm) or when complete joint penetra- 
tion cannot be verified by visual inspection. The two partial 
penetration welds may be any desired combination of fillet, 
single-bevel, and single-J welds. The dimension t w of each 
weld shall be not less than V 4 in. (6 mm) or O.lt and their 
sum shall be not less than lV^min (see Fig. HLW-431.1). 

HLW-431.3 Inserted Nozzles With Added Rein- 
forcement. Inserted-type nozzles having added reinforce- 
ment in the form of one or more separate reinforcement 
plates shall be attached by welds at the nozzle neck periph- 
ery and at the outer edge of each reinforcement plate. The 
weld at the outer edge of each reinforcement plate shall 
be a fillet weld with a minimum throat dimension of ^mi n . 

HLW-431.4 Nozzles With Integral Reinforcement. 

Nozzles and other connections having integral reinforce- 
ment in the form of extended necks or saddle-type pads 
shall be attached by a full-penetration weld or by means 
of a fillet weld along the outer edge and a fillet, single- 
bevel, or single-J weld along the inner edge. The throat 
dimension of the outer weld shall be not less than /^min- 
The dimension t w of the inner weld shall be not less than 
0.7/ min [see Fig. HLW-431.1, sketch (h)]. 

HLW-431.5 Fittings With Internal Threads and 
Studded Pads. The attachment of internally threaded fit- 
tings and studded pads shall meet the following require- 
ments: 

(a) Except as provided for in (b) below, internally 
threaded fittings shall be attached by a full-penetration 
groove weld or by two fillet or partial penetration welds, 
one on each face of the water heater wall. The minimum 
weld dimensions shall be as shown in Fig. HLW-431.5, 
sketches (u), (v), (w), and (x). 

(b) Internally threaded fittings or equivalent bolting 
pads not exceeding NPS 4 (DN 100) may be attached by 
a fillet weld deposited from the outside only, having the 
minimum dimensions shown in Fig. HLW-431.5, sketches 
(a) through (1). Fittings or studded pads that are not subject 
to a bending load and that will be plugged, such as those 
for thermostats, anode rods, drain valves, cleanouts, and 
heating elements, may be attached to water heater vessels 
having a thickness not greater than 3 / 8 in. (10 mm) by 
a fillet weld deposited from the outside only having the 
minimum dimensions shown in Fig. HLW-431.5, sketch 



154 



2007 SECTION IV 



FIG. HLW-431.1 SOME ACCEPTABLE TYPES OF WELDS FOR FITTINGS, NOZZLES, AND OTHER CONNECTIONS 

TO SHELLS AND HEAD 



Backing strip 
if used may 
be removed 
after welding 

(a) 




fc 



(b) 



(c) 



(d) 



:u 



T^ 



> 



* 



^' 2 





(f) 



(h) 



*1 +t 2 = 1-1/4 f min. 
f 1 or ?2 not 'ess than the 
smaller of 1/4 in. or 0.7 t min. 




t u , = 0J min. 




>?^ 



4*r /Y i 



P^ 



1/2 f min. 



155 



2007 SECTION IV 



FIG. HLW-431.5 SOME ACCEPTABLE TYPES OF WELDS FOR FITTINGS, NOZZLES, AND OTHER CONNECTIONS 

TO SHELLS AND HEAD 




(a) 



V/ 4 t min. 



(b) 




1 1 / 4 fmin. 1 1 / 4 fmin 

(g) (h) 







(i) 



(j) 





Either method of attachment is satisfactory 




<^\: 




h + t 2 = 1 1 / 4 fmin. 
(u-1) (u-2) (v-1) (v-2) 



t mm 



or t 2 not less than the smaller 
of V4 in. (6 mm) or OJt min. 

(w-1) (w-2) 



(y) 



t mm. 




3 / 8 in. max 




I 



^l 2 t min. 



r vu = OJt min. 



(x) 



^ 



(z) 



3 / 32 m - mm - ' e 9 



156 



2007 SECTION IV 



(y). The maximum size opening in the water heater vessel 
shall be 5 3 / 8 in. (136 mm) in any direction but not greater 
than one-half the vessel diameter. 

(c) Flange-type fittings not exceeding NPS 2 (DN 50) 
as shown in Fig. HLW-431.5, sketch (z) may be attached 
without additional reinforcement other than that in the 
fitting and its attachments, provided all of the following 
conditions are met: 

(1) the water heater wall thickness shall not exceed 
3 / 8 in. (10 mm) 

(2) the minimum fillet leg shall be 3 / 32 in. (2.5 mm) 

(3) the opening in the water heater wall shall not 
exceed the outside diameter of the nominal pipe plus 3 / 4 in. 
(19 mm) 

HLW-431.6 Internally Threaded Fittings Attached 
by Resistance Welding. Resistance welding may be used 
for the attachment of fittings under the following limita- 
tions and requirements: 

(a) The welding process utilized shall be limited to pro- 
jection welding. 

(b) Materials used in resistance welded parts shall be 
limited to a maximum carbon content of 0.15%. 

(c) The thickness t shall not exceed 5 / 16 in. (8 mm), and 
the fitting shall not exceed NPS 2 (DN 50). 

(d) The maximum allowable working pressure for a 
vessel with fittings attached by resistance welding shall be 
established by a proof test in accordance with HLW-500. 

(e) In lieu of the Procedure and Performance Qualifica- 
tion requirements of Section IX, the following require- 
ments shall be met: 

(1 ) Workmanship Samples 

(a) Three welded specimens of each combination 
of fitting size and base metal thickness employed shall be 
made immediately before and after the welding of the 
fittings for the proof test vessel. These test specimens shall 
be representative of the manufacturing practice employed 
in the attachment of the fittings to the proof test vessel. 
Sufficient base metal shall overlap the fitting to allow 
securement for the tensile test. 

(b) These welded specimens shall be subjected to 
tensile loading. Each specimen shall pass the tensile test 
by shearing the fitting or the base metal. Separation at the 
weld interface shall constitute failure. Any failure shall 
require a repeat of the workmanship sample test as herein 
required. 

(c) All pertinent information obtained from the 
foregoing tests shall be recorded. These samples and data 
constitute workmanship samples that shall be available for 
comparison with quality control specimens that are made 
during production. 

(2) Machine Settings and Controls 

(a) The resistance welding machine settings and 
process control parameters used in the attachment of the 



fittings to the proof test vessel and the workmanship sam- 
ples shall be recorded. Except for minor variations and 
adjustments as permitted in the above parameters, the appli- 
cable settings shall be used in the fabrication of all vessels 
in a given production run. 

(b) The machine settings and control shall be veri- 
fied by a test sample prior to the start of daily operations, 
after any service or adjustment is done on the welding 
equipment, and with every change in material or nominal 
thickness. 

(3) Records. Records shall be kept of all data obtained 
from tests of the proof test vessel, the workmanship sam- 
ples, the welding machine settings, the welding procedure, 
and process control parameters. 

(4) If resistance welding machines other than those 
used for the initial proof test vessel and workmanship 
samples are to be used in production, each additional 
machine and welding procedure shall be qualified in full 
accordance with (e)(1), (e)(2), and (e)(3) above. 

HLW-431.7 Stud Welds for Covers. Arc stud welding 
and resistance stud welding, as defined in E-101, where 
the pressure exerts a tensile load on the studs, may be used 
for the attachment of bolted unstayed flat heads, cover 
plates and blind flanges, handholes and manholes, with the 
following limitations: 

(a) Studs attached by stud welding shall not be in direct 
contact with products of combustion or flue gases. 

(b) Where the pressure exerts a tensile load on the studs, 
a full face gasket must be used on flat heads, cover plates, 
and blind flanges attached by stud welding. 

(c) The minimum size stud used shall be not less than 
/4 in. (6 mm) nominal diameter and the maximum size 
shall not exceed 7 / 8 in. (22 mm) nominal diameter. 

(d) The type of stud shall be limited to round externally 
threaded studs. 

(e) Base metal shall be of ferrous material specification 
as permitted by this Section, and the base metal must be 
thick enough to prevent burn through. 

(f) Stud material for arc stud welding and resistance 
stud welding of carbon steel shall be low carbon steel of 
an acceptable material in this Section and with a carbon 
maximum of 0.27% and with a minimum tensile strength 
of 60,000 psi (400 MPa). 

(g) The maximum spacing of studs shall not exceed 12 
times the nominal diameter of the stud. 

(h) The maximum allowable stress for the stud shall be 
7,800 psi (54 MPa) based on the smallest cross-sectional 
area (i.e., the root of the thread). 

HLW-431.8 Stud Welds for Internally Threaded Fit- 
tings. Arc stud welding and resistance stud welding, as 
defined in E-101, may be used for the mechanical attach- 
ment of fittings used to secure piping to vessel shells and 
heads with the following limitations. 



157 



2007 SECTION IV 



(a) Mechanically attached internally threaded fittings 
shall be limited to a maximum NPS 3 (DN 80) and shall 
be secured by a minimum of four studs. 

(b) Daily production weld tests shall be per HLW-460.5. 

(c) Stud welds used for the mechanical attachment of 
internally threaded fittings shall meet the provisions of 
HLW-431.7. 

( d) Gaskets for internally threaded fittings mechanically 
attached using arc- or resistance-welded studs may be of 
the flat or ring type, made of a material suitable for service 
at a minimum of 210°F (99°C). When ring-type gaskets 
are employed, a suitable recess shall be provided in the 
fitting to accommodate the gasket. 

(e) The maximum allowable working pressure for a ves- 
sel with internally threaded fittings mechanically attached 
using arc- or resistance-welded studs shall be established 
by proof test in accordance with HLW-500. Each size of 
the proposed connection shall be tested including the gasket 
method, studs, and internally threaded fittings. 

HLW-431.9 Friction Welding. Materials joined by the 
inertia and continuous drive friction welding processes 
shall be limited to material assigned P-Numbers in Section 
IX and shall not include rimmed or semikilled steel. 



HLW-432 BRAZED CONNECTIONS FOR 
COPPER LINED VESSELS 

Brazing shall meet the applicable requirements of Sub- 
part HB, Articles 10 through 15, inclusive. Some accept- 
able brazed connections are as shown in Fig. HLW-432. 1. 



HLW-440 WELDING PROCESSES 

The welding processes that may be used under this Part 
are restricted to the following: 

(a) Arc or gas welding processes are restricted to 
shielded metal arc, submerged arc, gas metal arc, gas tung- 
sten arc, plasma arc, atomic hydrogen metal arc, laser 
beam, electron beam, oxyhydrogen, and oxyacetylene. 

(b) Pressure welding processes are restricted to flash, 
induction, resistance, pressure thermit, pressure gas, and 
inertia and continuous drive friction welding. 

(c) Definitions are given in Section DC, which includes 
variations of these processes. 



Some linings require an elevated temperature for proper 
application. These elevated temperatures are not to be con- 
sidered a form of heat treatment for welding procedure 
qualification. 

HLW-451 PRODUCTION WORK 
QUALIFICATIONS 

(a) No production work shall be undertaken until the 
procedures, the welders, and the welding operators have 
been qualified, except that performance qualification by 
radiography, in conformance with Section IX, QW-304 
for welders or QW-305 for welding operators, may be 
performed within the first 3 ft (1 m) of the first produc- 
tion weld. 

(b) Welders, including brazers, and welding and brazing 
operators not in the employ of the manufacturer (Certificate 
of Authorization Holders) may be used to fabricate water 
heaters or parts thereof constructed in accordance with the 
Section, provided all of the following conditions are met: 

(1 ) All Code construction shall be the responsibility 
of the Manufacturer. 

(2) All welding shall be performed in accordance 
with the Manufacturer's welding procedure specifications 
that have been qualified by the Manufacturer in accordance 
with the requirements of Section IX and this Section. 

(3) All welders shall be qualified by the Manufacturer 
in accordance with the requirements of Section IX and this 
Section. 

(4) The Manufacturer's quality control system shall 
include as a minimum: 

(a) a requirement for complete and exclusive 
administrative and technical supervision of all welders by 
the Manufacturer 

( b) evidence of the Manufacturer' s authority to 
assign and remove welders at his discretion without 
involvement of any other organization 

(c) a requirement for Assignment of Welder Identi- 
fication symbols 

(d) evidence that this program has been accepted 
by the Manufacturer's Authorized Inspection Agency that 
provides the inspection service 

(5) The Manufacturer shall be responsible for Code 
compliance of the completed vessel or part, including Code 
symbol stamping and providing Data Report Forms prop- 
erly executed and countersigned by the Inspector. 



HLW-450 WELDING QUALIFICATIONS 

Unless otherwise specified in this Part the procedures, 
the welders, and the welding operators used in welding 
pressure parts and in joining nonpressure parts (attach- 
ments) to pressure parts shall be qualified in accordance 
with Section IX. 



HLW-452 INTERCHANGE OF QUALIFYING 
TESTS AMONG MANUFACTURERS 
PROHIBITED 

The performance qualification tests for welders and 
welding operators conducted by one manufacturer or con- 
tractor shall not qualify a welder or welding operator to 
do work for any other manufacturer or contractor. 



158 



2007 SECTION IV 



FIG. HLW-432.1 SOME ACCEPTABLE TYPES OF BRAZED FITTINGS, NOZZLES, AND OTHER CONNECTIONS TO 

COPPER-LINED SHELLS AND HEADS 



Joint clearance 
(see Table HB-1305) 




Steel 



Copper sheet 



Flow of filler metal 



Optional filler metal rings 
installed prior to swaging 



Swage flange on 
tank exterior 



103 



(a) 



Joint clearance 
(see Table HB-1305) 



Steel — 



Copper sheet 



Flow of filler metal 



r-\ 




Optional filler metal rings 
installed prior to swaging 



Swage flange on 
tank exterior 



o 



Tap threads after swaging 
and brazing operations 



(b) 



159 



2007 SECTION IV 



HLW-453 MAINTENANCE OF RECORDS OF 
QUALIFICATIONS AND 
IDENTIFYING MARKS 

The Manufacturer or contractor shall maintain qualifica- 
tion records of the welding procedures and welders and 
welding operators employed by him showing the date and 
results of test and the identification mark assigned to each 
welder. These records shall be certified to by the Manufac- 
turer or contractor by signature or some other method 
of control in accordance with the Manufacturer's quality 
control system, and be accessible to the Inspector. The 
welder or welding operator shall stamp his identification 
mark on or adjacent to all welded joints made by him at 
intervals of not greater than 3 ft (0.9 m), or the Manufac- 
turer shall keep a record of the welded joints on a water 
heater vessel and the welders and welding operators used 
in making the joints. 



HLW-454 POSTHYDROTEST WELDING OF 
NONPRESSURE PARTS TO 
PRESSURE PARTS 

Nonpressure parts may be welded to pressure parts after 
the hydrostatic test has been performed as set forth in 
HLW-505, provided the following criteria are met: 

(a) The material requirements shall comply as follows: 

(1) The pressure part material is limited to P-No. 1, 
Group 1 or 2 materials. 

(2) The nonpressure attachment material is limited to 
carbon steel with a carbon content not exceeding 0.20% 
or any P-No. 1 material. 

(3) When the nonpressure attachment material is 
other than P-No. 1, a minimum 200°F (93°C) preheat shall 
be applied when the pressure part thickness exceeds 4 i Q - 
(19 mm). 

(b) The attachment is done by stud welding, or by fillet 
welding where the throat of the weld does not exceed the 
lesser of 1 .5 times the thickness of the pressure part or V 4 
in. (6 mm). 

(c) The completed weld is inspected by the Authorized 
Inspector. 

(d) The Manufacturer's Data Report Form shall be 
signed only after the completion of the welding. 

HLW-460 SPECIFIC WELDING 
REQUIREMENTS 
HLW-460. 1 Finished Longitudinal and Circumfer- 
ential Joints 

(a) Butt welded joints shall have complete penetration 
and full fusion. The surface of the weld may be left as- 
welded provided the weld is free of coarse ripples, grooves, 
overlaps, abrupt ridges, or valleys. A reduction in thickness 
due to the welding process is acceptable provided all of 
the following conditions are met: 



(1) The reduction in thickness shall not reduce the 
material of the adjoining surfaces below the minimum 
required thickness at any point. 

(2) The reduction in thickness shall not exceed J / 3 2 in. 
(0.8 mm) or 10% of the nominal thickness of the adjoining 
surface, whichever is less. 1 

HLW-460.2 Fillet Welds. In making fillet welds, the 
weld metal shall be deposited in such a way that adequate 
penetration into the base metal at the root of the weld is 
secured. The reduction of the thickness of the base metal 
due to the welding process at the edges of the fillet weld 
shall meet the same requirements as for butt welds [see 
HLW-460. 1]. 

HLW-460.3 Double-Welded Butt Joints. Before 
applying weld metal on the second side to be welded, the 
root of double- welded butt joints shall be prepared by 
suitable methods such as chipping, grinding, or thermal 
gouging, so as to secure sound metal at the base of weld 
metal deposited on the face side, except for those processes 
of welding by which proper fusion and penetration are 
otherwise obtained and by which the root of the weld 
remains free from impurities. 

HLW-460.4 Repair of Weld Defects. Visible defects, 
such as cracks, pinholes, and incomplete fusion, and defects 
detected by leakage tests shall be removed by mechanical 
means or by thermal grooving processes, after which the 
joint shall be rewelded and reexamined. 

HLW-460.5 Stud Welding. In the case where arc stud 
welding and resistance stud welding is used to attach load 
carrying studs, a production stud weld test of the procedure 
and welding operator shall be performed on five studs, 
welded and tested in accordance with either the bend or 
torque stud weld testing described in Section IX as follows: 

(a) prior to start of daily operation if used continuously 
on units of similar construction 

(b) prior to the start of application to a given unit when 
not used continuously 

(c) after adjustment or servicing is done on welding 
equipment 

HLW-460.6 Procedure and Performance Qualifica- 
tion Tests and Material Requirements for Stud Weld- 
ing. Procedure and performance qualification tests for stud 
welds shall be made in accordance with Section IX. Further 
requirements for stud welding are as follows: 

(a) Metallic coatings (such as cadmium plating) if used 
shall not be within V 2 in. (13 mm) from the weld end of 
the stud. 



1 It is not the intent of this paragraph to require measurement of 
reductions in thickness due to the welding process. If a disagreement 
between the Manufacturer and the Inspector exists as to the acceptability 
of any reduction in thickness, the depth shall be verified by actual mea- 
surement. 



160 



2007 SECTION IV 



(b) The base metal must be above 50°F (10°C) during 
the welding process. 

HLW-460.7 Stud Welding. In the case where stud 
welding and resistance stud welding are used for joining 
nonpressure bearing attachments, which have essentially 
no load carrying function (such as extended heat transfer 
surfaces, insulation attachment pins, etc), to pressure parts 
by any automatic welding process performed in accordance 
with a Welding Procedure Specification (in compliance 
with Section IX as far as applicable), procedure and per- 
formance qualification testing is not required. 

In the case where stud welding is used to attach nonload- 
carrying studs, a production stud weld test, appropriate to 
the end use application requirements, shall be specified by 
the Manufacturer or assembler and carried out on a separate 
test plate or tube as follows: 

(a) prior to start of daily operation if used continuously 
on units of similar construction 

(b) prior to the start of application to a given unit when 
not used continuously 

(c) after adjustment or servicing is done on welding 
equipment 

HLW-460.8 Tack Welds. Tack welds used to secure 
alignment shall either be removed completely when they 
have served their purpose, or their stopping and starting 
ends shall be properly prepared by grinding or other suit- 
able means so that they may be satisfactorily incorporated 
into the final weld. Tack welds, whether removed or left 



in place, shall be made using a fillet weld or butt weld 
procedure qualified in accordance with Section IX. Tack 
welds to be left in place shall be made by welders qualified 
in accordance with Section IX and shall be examined visu- 
ally for defects, and if found defective, shall be removed. 
It is not necessary that a subcontractor performing such 
tack welds for the vessel manufacturer be a holder of an 
ASME Certificate of Authorization. If the tack welds are 
permanently left in place, the final vessel manufacturer 
shall maintain the controls to assure that the necessary 
welding procedure and performance qualifications are met 
in order to satisfy Code requirements. 

HLW-460.9 Friction Welding 

(a) When joining two parts by the inertia and continuous 
drive friction welding processes, one of the two parts must 
be held in a fixed position and the other part rotated. The 
two faces to be joined must be essentially symmetrical 
with respect to the axis of rotation. Some of the basic types 
of applicable joints are solid round to solid round, tube to 
tube, solid round to tube, solid round to plate, and tube 
to plate. 

(b) The welded joint between two members joined by 
the inertia and continuous drive friction welding processes 
shall be a full penetration weld. Visual examination of the 
as-welded flash roll of each weld shall be made as an in- 
process check. The weld upset shall meet the specified 
amount within ±10%. The flash shall be removed to sound 
metal. 



161 



2007 SECTION IV 



ARTICLE 5 
TESTS 



HLW-500 TESTS TO ESTABLISH MAXIMUM 

ALLOWABLE WORKING PRESSURE 
AND PRODUCTION LINE TESTS 

HLW-501 GENERAL 

The required thickness for pressure parts and the maxi- 
mum allowable working pressure for vessels that are not 
based upon the formulas of Article 3 shall be established 
by a proof test. The proof test shall consist of the application 
of hydrostatic pressure to a full size sample of a vessel. 
Material in excess of the material thicknesses or of higher 
strengths than specified for parts of proof test vessel(s) shall 
be acceptable for production of such parts. The maximum 
allowable working pressure for a series of vessels may be 
established by a proof test on one vessel from the series, 
or two vessels from the series if the ligament spacing 
differs. Vessels with the smallest and largest ligament spac- 
ing on the heads shall be tested. 

Vessels in the series shall have 

(a) heads of the same geometry and thickness 

(b) cylindrical shell and tube(s), if used, that differ only 
by length, and 

(c) openings of the same size and type as those present 
on the vessel proof tested 

Optional openings in the shell may be added in accor- 
dance with the provisions of HLW-308. 

Optional openings in the heads may be added in accor- 
dance with the provisions of HLW-308 if such head open- 
ings are located entirely within a circle, the center of which 
coincides with the center of the head and the diameter of 
which is equal to 80% of the head diameter. 



HLW-502 PROOF TEST 
HLW-502.1 Test Procedure 

(a) Hydrostatic pressure previously applied to the vessel 
to be proof tested shall not have exceeded 1 \ times the 
anticipated maximum allowable working pressure. 

(b) The outer surface of the vessel shall be suitably 
cleaned. A brittle coating shall be applied. The technique 
shall be suited to the coating material. 

(c) The hydrostatic pressure shall be increased gradually 
until approximately one-half the anticipated maximum 
allowable working pressure is reached. Thereafter, the test 



pressure shall be increased in steps of approximately \q 
or less of the anticipated maximum allowable working 
pressure. The pressure shall be held stationary at the end 
of each increment for a sufficient time to allow the observa- 
tions required by the test procedure to be made, and shall be 
released to zero to permit determination of any permanent 
strain or displacement after any pressure increment that 
indicates an increase in strain or displacement over the 
previous equal pressure increment as evidenced by flaking 
of the brittle coating, or by the appearance of strain lines. 
The application of pressure shall be stopped when the 
intended test pressure has been reached, or at the first sign 
of yielding. 

(d) The yield strength shall be the average of three 
specimens cut from the part tested after the test is com- 
pleted. The specimens shall be cut from a location where 
the stress during the test has not exceeded the yield strength. 
When excess stock from the same piece of wrought mate- 
rial is available the test specimens may be cut from this 
excess stock. The specimens shall not be removed by flame 
cutting or any other method involving sufficient heat to 
affect the properties of the specimen. 

(e) The maximum allowable working pressure P in psi 
for the water heater tested under this paragraph shall be 
computed by one of the following formulas: 

( 1 ) if the average yield strength is determined in 
accordance with HLW-502. 1(d) above, 



P = 0.5H j- 



(2) to eliminate the necessity of cutting tensile speci- 
mens and determining the actual yield strength of the mate- 
rial under test, or when the test has been stopped before 
any yielding, one of the following formulas may be used 
to determine the maximum allowable working pressure: 

(a) for carbon steel meeting an acceptable Code 
Specification, with a specified minimum tensile strength 
of not over 70,000 psi (480 MPa), 



(U.S. Customary Units) 

P = 0.5H 



S + 5,000 



162 



2007 SECTION IV 



(SI Units) 



P = 0.5H 



5 + 34 500 



(b) for any acceptable material listed in Section IV, 
P = OAH 

where 

H = hydrostatic test pressure at which the test was 

stopped, psi (kPa) 
S = specified minimum tensile strength, psi (kPa) 
Y a = actual average yield strength from test specimens, 

psi (kPa), as outlined in HLW-502.1(d) 
Y s = specified minimum yield strength, psi (kPa) 

When either of the formulas in (a) and (b) above is used, 
the material in the pressure part shall have no appreciable 
cold working or other treatment that would tend to raise 
the yield strength above the normal. 

NOTE: Due to the geometry of parts commonly used in lined water 
heaters, yielding due to bending often occurs at pressures that are unusu- 
ally low compared to burst strength. When an analysis of the test indicates 
yielding occurred in bending, P may be multiplied by 1.5. 

HLW-502.2 Test Gages 

(a) An indicating gage shall be connected directly to 
the water heater vessel. Intermediate pipe and fittings may 
be used provided there are no intervening valves. If the 
indicating gage is not readily visible to the operator control- 
ling the pressure applied, an additional indicating gage 
shall be provided where it will be visible to the operator 
throughout the duration of the test. For large water heater 
vessels, it is recommended that a recording gage be used 
in addition to indicating gages. 

(b) Dial indicating pressure gages used in testing shall 
be graduated over a range of about double the intended 
maximum test pressure, but in no case shall the range be 
less than 1 \ nor more than 4 times that pressure. Digital 
reading pressure gages having a wider range of pressure 
may be used provided the readings give the same, or 
greater, degree of accuracy as obtained with dial pressure 
gages. 

(c) All gages shall be calibrated against a standard dead- 
weight tester or a calibrated master gage. Gages shall be 
recalibrated at any time that there is reason to believe that 
they are in error. 



HLW-503 TESTING OF PARTS 

HLW-503.1 Parts of vessels subject to collapse that 
have not been proof tested in accordance with HLW-502 
and for which specified rules are not provided in this Part 
shall withstand, without excessive deformation, a hydro- 
static test of not less than three times the desired maximum 
allowable working pressure. 

HLW-503.2 Cast parts for vessels may have a maxi- 
mum allowable working pressure established by the burst- 
ing test procedure of HG-502.3. 



HLW-504 WITNESSING, RECORDING, AND 
CERTIFYING TESTS 

Tests to establish the maximum allowable working pres- 
sure of complete vessels or parts shall be witnessed by the 
manufacturer's personnel designated to be responsible for 
the examination. These tests shall also be witnessed and 
accepted by the Authorized Inspector. These proof tests 
shall be recorded on Form HLW-8, Manufacturer's Master 
Data Proof Test Report for Water Heaters or Storage Tanks. 
The completed form shall be certified by the designated 
responsible engineering head of the manufacturer. These 
forms shall be kept on file by the manufacturer as a matter 
of record. 



HLW-505 HYDROSTATIC TEST 

HLW-505.1 All water heater vessels shall be subjected 
to a hydrostatic test of \\ times the maximum allowable 
working pressure with the exception that the test pressure 
for glass-lined, and fluorocarbon polymer-lined, or amine 
or polyamine epoxy-lined water heater vessels shall be at 
least equal to, but not exceed within the tolerances of test 
pressure in HLW-505. 2, the maximum allowable working 
pressure to be marked on the water heater vessel. Water 
heater vessels that are to be galvanized or cement-lined 
may be pressure tested either before or after galvanizing 
or cement lining. 

HLW-505.2 While under the hydrostatic test pressure 
an inspection for leakage shall be made of all joints and 
connections. In making hydrostatic pressure tests the pres- 
sure shall be under such control that in no case shall the 
required test pressure be exceeded by more than 10 psi 
(70 kPa). 



163 



2007 SECTION IV 



ARTICLE 6 
INSPECTION AND STAMPING 



HLW-600 INSPECTION AND CERTIFICATION 
HLW-600.1 Inspection by Authorized Inspector. The 

inspection required by this Part shall be by an Inspector 
employed by an ASME accredited Authorized Inspection 
Agency, 1 that is, the inspection organization of a State or 
Municipality of the United States, a Canadian Province, 
or an Inspector of an insurance company authorized to 
write boiler and pressure vessel insurance. These Inspectors 
shall have been qualified by written examination under the 
rules of any State of the United States or Province of 
Canada that has adopted the Code. 

HLW-600.2 Manufacturer's Responsibility 

(a) The manufacturer who completes any vessel to be 
marked with the Code HLW Symbol has the responsibility 
of complying with all requirements of this Part, and through 
proper certification of assuring that any work done by 
others also complies with the requirements of this Part. 

( b) The manufacturer has the responsibility of providing 
the Authorized Inspector with all specified information and 
assurance that the quality control system is in compliance 
with that outlined in Appendix F. These responsibilities 
shall include, but are not limited to, providing or making 
available for review the following: 

(1) a valid Certificate of Authorization for use of the 
HLW Symbol from the ASME Boiler and Pressure Vessel 
Committee (see HLW-602) 

(2) the design calculations per Article 3 or the certi- 
fied proof test results per Article 5 and associated drawings 
(see HLW-300 and HLW-500) 

(3) identification of materials to show compliance 
with Articles 2 and 3 and compliance with the provisions 
of Section IX (see HLW-200 and HLW-300) 

(4) evidence of qualification of welding and /or braz- 
ing procedures (see HLW-432 and HLW-450) 

(5) records of qualifications of each welder, welding 
operator, or brazer as evidence of compliance with the 
provisions of Section IX (see HLW-432 and HLW-450) 

(6) any Manufacturer's Partial Data Reports when 
required by HLW-601.2 



1 Whenever Authorized Inspection Agency or AIA is used in this 
Code, it shall mean an ASME Accredited Authorized Inspection Agency 
accredited by ASME in accordance with the latest edition of QAI-1. 



(7) evidence of examination of materials before fabri- 
cation to make certain it has the required thickness, has 
no unacceptable indications, and is one of the acceptable 
materials permitted by this Part and that traceability to the 
material identification has been maintained [see 
HLW-201(c) and F-202.4] 

(8) the manufacturer shall submit the vessel or other 
pressure part for inspection at such stages of the work as 
may be designated by the Inspector 

HLW-600.3 Authorized Inspector's Duty 

(a) The Authorized Inspector shall make such inspec- 
tions as he believes are needed to enable him to certify 
that the vessels have been constructed in accordance with 
the rules of this Part. He shall assure himself that the 
manufacturer is complying with all of the requirements of 
this Part. 

(b) It is the duty of the Inspector to assure himself 
that the welding procedures employed in construction are 
qualified under the provisions of Section IX. The manufac- 
turer shall submit evidence to the Inspector that those 
requirements have been met. 

(c) It is the duty of the Inspector to assure himself 
that all welding is done by welders or welding operators 
qualified under the provisions of Section DC. The manufac- 
turer shall make available to the Inspector a certified copy 
of the record of performance qualification tests of each 
welder and welding operator as evidence that these require- 
ments have been met. 

The Inspector has the right at any time to call for and 
witness the test welding and testing although it is not 
mandatory that he witness the test welding and the testing 
unless he so desires. 

(d) The provisions of HG-5 15.4(b) apply to the fabrica- 
tion of multiple duplicate water heaters and storage tanks. 



HLW-601 MANUFACTURER'S DATA AND 
PARTIAL DATA REPORTS 
HLW-601.1 Manufacturer's Data Report 

(a) Each manufacturer shall complete a Manufacturer's 
Data Report for each vessel he produces. Form HLW-6 
may be used. Individual manufacturer's data reports, if 
used, will satisfy the requirements for the Manufacturers' 



164 



2007 SECTION IV 



Data Report. The report may cover a single vessel or may 
include the serial numbers in uninterrupted sequence of 
identical vessels completed, inspected, and stamped in a 
continuous 8 hr period. 

(b) The manufacturer shall have the responsibility of 
furnishing a copy of the completed Manufacturer's Data 
Report at the place of installation to the inspection agency, 
the purchaser, and the state, municipal, or provincial 
authority. The manufacturer shall either keep a copy of 
the Manufacturers' Data Report on file for at least 5 years, 
or the vessel may be registered and the original Data Report 
filed with the National Board of Boiler and Pressure Vessel 
Inspectors, 1055 Crupper Avenue, Columbus, Ohio 43229. 

HLW-601.2 Partial Data Reports 

(a) Manufacturer's Partial Data Reports for those parts 
of a vessel requiring inspection under this Code, which 
are furnished by other than the shop of the manufacturer 
responsible for the completed heater, shall be executed by 
the parts manufacturer and shall be forwarded in duplicate, 
to the manufacturer of the finished vessel. 

(b) Partial Data Reports (Form HLW-7) shall be com- 
pleted for all parts that require inspection under this Code 
that are fabricated by a manufacturer other than the manu- 
facturer of the completed vessel, regardless of whether 
individual Manufacturer's Data Reports are compiled for 
the completed units. These Partial Data Reports, together 
with his own inspection, shall be the final Inspector's 
authority to witness the application of a Code Symbol to 
the completed vessel. 

HLW-601.3 Supplementary Sheet. Form H-6, Manu- 
facturer's Data Report Supplementary Sheet, shall be used 
to record additional data where space was insufficient on 
a Data Report Form. This Manufacturer's Data Report 
Supplementary Sheet will be attached to the Manufactur- 
er's Data Report Form where used. 



HLW-602 STAMPING OF WATER HEATERS 
AND STORAGE TANKS 
HLW-602.1 Stamping Requirements for Vessels. All 

vessels to which the Code Symbol is to be applied shall 
be built according to the rules of this Part by a manufacturer 
who is in possession of a Code Symbol Stamp and a valid 
Certificate of Authorization per procedure of HG-540. Each 
vessel shall be marked or stamped with the Code Symbol 
shown in Fig. HLW-602. 1 and the form of stamping shown 
in Fig. HLW-602.2 with the following data: 

(a) the manufacturer's name, preceded by the words 
"Certified by." 

(b) maximum allowable working pressure. 

(c) maximum allowable input in Btu/hr; electric heat- 
ers may use kW or Btu/hr (expressed at the rate of 3,500 
Btu/hr per kW) or both. In lieu of the input markings 



FIG. HLW-602.1 OFFICIAL SYMBOL TO DENOTE THE 

AMERICAN SOCIETY OF MECHANICAL ENGINEERS' 

STANDARD 




FIG. HLW-602.2 FORM OF STAMPING ON 
COMPLETED WATER HEATERS 




Certified by 



(Name of manufacturer) 
Maximum Allowable W. P. psi 



Maximum Allowable Input 

Manufacturer's Serial No. _ 
Year built 



Btu/hr 
kW 



storage tanks shall be marked "Storage Only." 

(d) manufacturer's serial number (this may be a serial 
number or a combination model and serial number). 

(e) year built (the year built may be incorporated into 
the serial number). 

HLW-602.2 Stamping a Proof Tested Vessel. A com- 
pleted vessel or one tested prior to lining may have the 
required Code Symbol and marking applied, provided 

(a) the proof test was stopped before any visible 
yielding 

(b) all welding was qualified as required by HLW-451 

(c) the MAWP is calculated by the method of 
HLW-502. 1(d)(2) 

(d) the interior of a lined vessel must be inspected to 
verify that it was not damaged, and 

(e) the completed vessel is subjected to the hydrostatic 
test provisions of HLW-505 

HLW-602.3 When the Code Symbol and marking 
required by HLW-602.1, items (7) through (5), is applied 
directly to the water heater vessel, it shall be stamped with 
letters and figures at least 5j 6 in. (8 mm) high or on a 
stamping plate at least %4 in. (1.2 mm) thick permanently 
fastened to the water heater vessel. Stamping plates bearing 
the stamping and marking required in HLW-602.1 may be 
used in lieu of stamping these data directly on the water 
heater vessel if the stamping plates are permanently 



165 



2007 SECTION IV 



attached to the water heater vessel. In this case the required 
data on the stamping plate shall be in characters not less 
than \ in. (3 mm) high. 

If the required marking or stamping is to be covered 
by insulation, jacket, or other form of casing, one of the 
following shall be provided: 

(a) an opening with a removal cover for viewing the 
marking or stamping. 

(b) a nameplate, located in a conspicuous place on the 
jacket, duplicating the required Code Symbol and data. 
This plate shall be at least 3 in. x 4 in. (75 mm x 100 mm) 
in size marked with letters and numerals at least \ in. 
(3 mm) high and of either metallic material attached by 
mechanical means or of any material attached by an adhe- 
sive system meeting the requirements of Appendix 3. 



HLW-602.4 Parts for which a Partial Data Report, 
Form HLW-7, is required by HLW-601.2, shall be marked 
with the following: 

(a) the official symbol shown in Fig. HLW-602.1 above 
the word "Part" 

(b) the part manufacturer's name 

(c) the part manufacturer's serial number 

In lieu of stamping these data directly on the vessel, a 
stamping plate, as described in HLW-602.3, may be used. 

HLW-602.5 Water heaters fabricated of austenitic 
stainless steel material listed in Table HLW-301 shall have 
a precautionary statement warning that the water heaters 
are to be operated only on deionized water having a mini- 
mum specific resistivity of 1.0 M/2/cm clearly marked and 
located on the water heater so that it will be readily visible. 



166 



2007 SECTION IV 



ARTICLE 7 
CONTROLS 



HLW-700 CONTROLS 

HLW-701 TEMPERATURE CONTROL 

HLW-701.1 Each individual automatically fired water 
heater, in addition to the operating control used for normal 
water heater operation shall have a separate high tempera- 
ture limit control that will automatically cut off the fuel 
supply. The temperature range of the high temperature 
limit control shall not allow a setting over 210°F (99°C). 

(a) On gas-fired water heaters, the high temperature 
limit control when actuated shall shut off the fuel supply 
with a shutoff means other than the operating control valve. 
Separate valves may have a common body. 

(b) On electrically heated water heaters, the high tem- 
perature limit control when actuated shall cut off all power 
to the operating controls. 

(c) On oil-fired water heaters, the high temperature limit 
control when actuated shall cut off all current flow to the 
burner mechanism. 

(d) On indirect water heating systems, the high tempera- 
ture limit control when activated shall cut off the source 
of heat. 



switches, and burners, or electric elements as required by 
a nationally recognized standard. 1 

(b) The symbol of the certifying organization 2 that has 
investigated such equipment as having complied with a 
nationally recognized standard shall be affixed to the equip- 
ment and shall be considered as evidence that the controls 
and heat generating apparatus were manufactured in accor- 
dance with that standard. 



HLW-704 ELECTRICAL WIRING 

HLW-704.1 Electrical Code Compliance. All field 
wiring for controls, heat generating apparatus, and other 
appurtenances necessary for the operation of the water 
heater should be installed in accordance with the provisions 
of the National Electrical Code and /or should comply with 
the applicable local electrical codes. All water heaters sup- 
plied with factory mounted and wired controls, heat gener- 
ating apparatus, and other appurtenances necessary for the 
operation of the water heaters should be installed in accor- 
dance with the provisions of the nationally recognized 
standards such as listed in footnote 1 of HLW-703. 



HLW-702 LIMIT CONTROLS 

Limit controls used with electric circuits should break 
the hot or line sides of the control circuit. 



HLW-703 CONTROLS AND HEAT 

GENERATING APPARATUS 

(a) All water heaters should be equipped with suitable 
primary (flame safeguard) safety controls, safety limit 



1 Examples of these nationally recognized standards that are currently 
effective: 

ANSI/UL 732, Standard for Oil-Fired Storage Tank Water Heaters. 

American National Standard/CSA Standard ANSI Z21.10.3/CSA 4.3 
for Gas Water Heaters, Volume HI, Storage Water Heaters With Input 
Ratings Above 75,000 Btu Per Hour, Circulating and Instantaneous. 

Underwriters Laboratories, Inc., UL 795, Standards for Safety, Com- 
mercial-Industrial Gas-Heating Equipment. 

Underwriters Laboratories, Inc., UL 1453, Standards for Safety, Elec- 
tric Booster and Commercial Storage Tank Water Heaters. 

2 A certifying organization is one that provides uniform testing, exami- 
nation, and listing procedures under established, nationally recognized 
standards and that is acceptable to the authorities having jurisdiction. 



167 



2007 SECTION IV 



ARTICLE 8 
INSTALLATION REQUIREMENTS 



HLW-800 SAFETY RELIEF VALVES 

HLW-800.1 Safety Relief Valve Requirements for 
Water Heaters 

(a) Each water heater shall have at least one officially 
rated temperature and pressure safety relief valve or at 
least one officially rated safety relief valve. The valve(s) 
shall be marked with the ASME Code Symbol V or HV 
to evidence compliance with the construction and rating 
requirements of the ASME Boiler and Pressure Vessel 
Code. No safety relief valve shall be smaller than NPS % 
(DN 20). 

(b) The pressure setting shall be less than or equal to 
the maximum allowable working pressure of the water 
heater. However, if any of the other components in the hot 
water supply system (such as valves, pumps, expansion or 
storage tanks, or piping) have a lesser working pressure 
rating than the water heater, the pressure setting for the 
relief valve(s) shall be based upon the component with the 
lowest maximum allowable working pressure rating. If 
more than one safety relief valve is used, the additional 
valve(s) may be set within a range not to exceed 10% over 
the set pressure of the first valve. 

(c) The required relieving capacity in Btu/hr of the 
safety relief valve shall not be less than the maximum 
allowable input unless the water heater is marked with the 
rated burner input capacity of the water heater on the casing 
in a readily visible location, in which case the rated burner 
input capacity may be used as a basis for sizing the safety 
relief valves. The relieving capacity for electric water heat- 
ers shall be 3,500 Btu/hr (1.0 kW) per kW of input. In 
every case, the following requirements shall be met. Safety 
relief valve capacity for each water heater shall be such 
that with the fuel burning equipment installed and operated 
at maximum capacity the pressure cannot rise more than 
10% of maximum allowable working pressures. 

(d) If operating conditions are changed or additional 
heater heating surface is installed, the safety relief valve 
capacity shall be increased, if necessary, to meet the new 
conditions and shall be in accordance with the above provi- 
sions. In no case shall the increased input capacity exceed 
the maximum allowable input capacity. The additional 
valves required, on account of changed conditions, may 
be installed on the outlet piping provided there is no 
intervening valve. 



HLW-801 MOUNTING SAFETY RELIEF 
VALVES 
HLW-801.1 Installation. Safety relief valves shall be 
installed by either the installer or the manufacturer before 
a water heater is placed in operation. 

HLW-801.2 Permissible Mountings. Safety relief 
valves shall be connected to the top of water heaters or 
directly to a tapped or flanged opening in the water heater, 
to a fitting connected to the water heater by a short nipple, 
to a Y-base, or to a valveless header connecting water 
outlets on the same heater. Safety relief valves shall be 
installed with their spindles upright and vertical with no 
horizontal connecting pipe, except that, when the safety 
relief valve is mounted directly on the water heater vessel 
with no more than 4 in. (100 mm) maximum interconnect- 
ing piping, the valve may be installed in the horizontal 
position with the outlet pointed down. The center line of 
the safety relief valve connection shall be no lower than 
4 in. (100 mm) from the top of the shell. No piping or 
fitting used to mount the safety relief valve shall be of a 
nominal pipe size less than that of the valve inlet. 

HLW-801.3 Requirements for Common Connection 
for Two or More Valves 

(a) When a water heater is fitted with two or more safety 
relief valves on one connection, this connection shall have 
a cross-sectional area not less than the combined areas of 
inlet connections of all the safety relief valves with which 
it connects. 

(b) When a Y-base is used, the inlet area shall be not 
less than the combined outlet areas. When the size of the 
water heater requires a safety relief valve larger than 4 l / 2 in. 
(1 14 mm) diameter, two or more valves having the required 
combined capacity shall be used. When two or more valves 
are used on a water heater, they may be single, directly 
attached, or mounted on a Y-base. 

HLW-801.4 Threaded Connections. A threaded con- 
nection may be used for attaching a valve. 

HLW-801.5 Prohibited Mountings. Safety relief 
valves shall not be connected to an internal pipe in the 
water heater or a cold water feed line connected to the 
water heater. 



168 



2007 SECTION IV 



HLW-801.6 Use of Shutoff Valves Prohibited. No 

shutoff of any description shall be placed between the 
safety relief valve and the water heater, or on discharge 
pipes between such valves and the atmosphere. 

HLW-801.7 Safety Relief Valve Discharge Piping 

(a) When a discharge pipe is used, its internal cross- 
sectional area shall be not less than the full area of the 
valve outlet or of the total of the valve outlets discharging 
thereinto, and shall be as short and straight as possible and 
so arranged as to avoid undue stress on the valve or valves. 
When an elbow is placed on a safety relief discharge pipe, 
it shall be located close to the valve outlet. 

(b) The discharge from safety relief valves shall be so 
arranged that there will be no danger of scalding attendants. 
When the safety relief valve discharge is piped away from 
the water heater to the point of discharge, there shall be 
provisions for properly draining the piping and valve body. 
The size and arrangement of discharge piping shall be such 
that any pressure that may exist or develop will not reduce 
the relieving capacity of the relieving devices below that 
required to protect the water heater. 



HL W-805 WATER SUPPLY 

HL W-805.1 Connections. Water supply shall be intro- 
duced into a water heater through an independent water 
supply connection. Feedwater shall not be introduced 
through openings or connections provided for cleaning, 
safety relief valves, drain, pressure gage, or temperature 
gage. 

HLW-805.2 Pressure. If the water supply pressure to 
a water heater exceeds 75% of the set pressure of the safety 
relief valve, a pressure reducing valve is required. 

HLW-805.3 Stop Valves. Stop valves should be placed 
in the supply and discharge pipe connections of a water 
heater installation to permit draining the water heater with- 
out emptying the system. 



HL W-808 STORAGE TANKS 

If a system is to utilize a storage tank that exceeds the 
capacity exception of HLW- 10 1.2(c), the tank shall be 
constructed in accordance with the rules of this Part; Sec- 
tion VIII, Division 1 ; or Section X. For vessels constructed 
to Section X, the maximum allowable temperature marked 
on the tank shall equal or exceed 210°F (99°C). 



TABLE HLW-809.1 

EXPANSION TANK CAPACITIES 

FOR A WATER HEATER 





Tank Capacities, gal (m 3 ) 


System Volume, 


Prepressurized 


Nonprepressurized 


gal (m 3 ) 


Diaphragm Type 


Type 


50 (0.19) 


1 (0.004) 


3 (0.011) 


100 (0.38) 


2 (0.006) 


6 (0.023) 


200 (0.76) 


3 (0.011) 


12 (0.045) 


300 (1.14) 


4 (0.015) 


18 (0.068) 


400 (1.51) 


5 (0.019) 


24 (0.091) 


500 (1.89) 


6 (0.023) 


30 (0.114) 


1,000 (3.79) 


12 (0.045) 


60 (0.227) 


2,000 (7.57) 


24 (0.091) 


120 (0.454) 



GENERAL NOTES: 

(a) Capacities in this Table are given as a guide to reduce or eliminate 
relief valve weeping under conditions of partial water system 
demands or occasional water draw during recovery. 

(b) System volume includes water heater capacity plus all piping capac- 
ity for a recirculation system or water heater capacity only for a 
nonrecirculation system. 

(c) The capacities are based upon a water temperature rise from 40°F 
to 180°F (4°C to 82°C), 60 psi (400 kPa) fill pressure, maximum 
operating pressure of 125 psi (850 kPa), 20% water recovery, 
and an acceptance factor of 0.465 for prepressurized types and 
0.09156 for nonprepressurized types. A procedure for estimating 
system volume and for determining expansion tank sizes for other 
design conditions may be found in Chapter 12 of the 1996 HVAC 
Systems and Equipment Volume of the ASHRAE Handbook. 



water inlet line, consideration should be given to the instal- 
lation of an airtight expansion tank or other suitable air 
cushion. Otherwise, due to the thermal expansion of the 
water, the safety relief valve may lift periodically. If an 
expansion tank is provided, it shall be constructed in accor- 
dance with Section VIII, Division 1 or Section X. See 
Fig. HLW-809.1 for a typical acceptable installation. 
Except for prepressurized diaphragm type tanks, which 
should be installed on the cold water side, provisions shall 
be made for draining the tank without emptying the system. 

HLW-809.2 Piping. Provisions shall be made for the 
expansion and contraction of hot water mains connected to 
water heaters by providing substantial anchorage at suitable 
points and by providing swing joints when water heaters 
are installed in batteries, so that there will be no undue 
strain transmitted to the water heaters. See 
Figs. HLW-809.1 and HLW-809.2 for typical schematic 
arrangements of piping incorporating strain absorbing 
joints. 



HLW-809 PROVISIONS FOR THERMAL 
EXPANSION IN HOT WATER 
SYSTEMS 
HLW-809.1 Expansion Tank. If a system is equipped 
with a check valve or pressure reducing valve in the cold 



HLW-810 BOTTOM DRAIN VALVE 

(a) Each water heater shall have a bottom drain pipe 
connection fitted with a valve or cock. These shall be 
connected at the lowest practicable point on the water 



07 



169 



2007 SECTION IV 



FIG. HLW-809.1 A TYPICAL ACCEPTABLE PIPING INSTALLATION FOR STORAGE 
WATER HEATERS IN BATTERY 



Pressure 
reducing valve 
if required 
(see HLW-805.2) 




Cold water supply 



Expansion tank 
if required 
(see HLW-809) 





-£&- 



1 « 1><\ \\\ — K 



Water heater 
with vertical 
top safety 
relief opening 

To open drain 



h isy 

^ — [><1 * l|l I 



I y — Drain valve with 

litable drain 



%S sui 



Point of use 



■i h 



Drain valve 




Water heater 
with side 
safety relief 
opening <t within 
4 in. (100 mm) of the 
top of the shell 

To open drain 



H^- 



A 



Drain valve 



Optional 
recirculation 
line [Noted)] 



Water Heater With Top 
Relief Opening 



Water Heater With Side 
Relief Opening 



GENERAL NOTE: Thermometer requirements are in HLW-820. 

NOTE: 

(1) Recirculation system may be gravity or pump actuated. 



heater, or to the lowest point on piping connected to the 
water heater, at the lowest practicable point on the water 
heater. The minimum size bottom drain valve shall be % in. 
(DN 20). 

(b) Any discharge piping connected to the bottom drain 
connection shall be full size to the point of discharge. 



HLW-820 THERMOMETER 

Each installed water heater shall have a thermometer so 
located and connected that it shall be easily readable. The 
thermometer shall be so located that it shall at all times 
indicate the temperature of the water in the water heater 
at or near the outlet. 



170 



2007 SECTION IV 



FIG. HLW-809.2 A TYPICAL ACCEPTABLE PIPING INSTALLATION FOR FLOW THROUGH WATER 
HEATER WITH PROVISIONS FOR PIPING EXPANSION 



Optional flow switch on 
flow through 
water heater 




Optional 
recirculation 
line 



Drain valve 



GENERAL NOTE: Thermometer requirements are in HLW-820. 



171 



172 



2007 SECTION IV 



APPENDICES 



MANDATORY APPENDIX 1 

SUBMITTAL OF TECHNICAL INQUIRIES TO THE 

BOILER AND PRESSURE VESSEL COMMITTEE 



1-100 



INTRODUCTION 



(a) This Appendix provides guidance to Code users for 
submitting technical inquiries to the Committee. See 
Guideline on the Approval of New Materials Under the 
ASME Boiler and Pressure Vessel Code in Section II, Parts 
C and D for additional requirements for requests involving 
adding new materials to the Code. Technical inquiries 
include requests for revisions or additions to the Code 
rules, requests for Code Cases, and requests for Code inter- 
pretations, as described below. 

(1 ) Code Revisions. Code revisions are considered to 
accommodate technological developments, address admin- 
istrative requirements, incorporate Code Cases, or to clarify 
Code intent. 

(2) Code Cases. Code Cases represent alternatives or 
additions to existing Code rules. Code Cases are written 
as a question and reply, and are usually intended to be 
incorporated into the Code at a later date. When used, 
Code Cases prescribe mandatory requirements in the same 
sense as the text of the Code. However, users are cautioned 
that not all jurisdictions or owners automatically accept 
Code Cases. The most common applications for Code 
Cases are 

(a) to permit early implementation of an approved 
Code revision based on an urgent need 

(b) to permit the use of a new material for Code 
construction 

(c) to gain experience with new materials or alter- 
native rules prior to incorporation directly into the Code 

(3) Code Interpretations. Code Interpretations pro- 
vide clarification of the meaning of existing rules in the 
Code, and are also presented in question and reply format. 
Interpretations do not introduce new requirements. In cases 
where existing Code text does not fully convey the meaning 



that was intended, and revision of the rules is required to 
support an interpretation, an Intent Interpretation will be 
issued and the Code will be revised. 

(b) The Code rules, Code Cases, and Code Interpreta- 
tions established by the Committee are not to be considered 
as approving, recommending, certifying, or endorsing any 
proprietary or specific design, or as limiting in any way 
the freedom of manufacturers, constructors, or owners to 
choose any method of design or any form of construction 
that conforms to the Code rules. 

(c) Inquiries that do not comply with the provisions of 
this Appendix or that do not provide sufficient information 
for the Committee's full understanding may result in the 
request being returned to the inquirer with no action. 



1-200 



INQUIRY FORMAT 



Submittals to the Committee shall include 

(a) Purpose. Specify one of the following: 

(1 ) revision of present Code rules 

(2) new or additional Code rules 

( 3) Code Case 

(4) Code Interpretation 

( b) Background. Provide the information needed for the 
Committee's understanding of the inquiry, being sure to 
include reference to the applicable Code Section, Division, 
Edition, Addenda, paragraphs, figures, and tables. Prefera- 
bly, provide a copy of the specific referenced portions of 
the Code. 

(c) Presentations. The inquirer may desire or be asked 
to attend a meeting of the Committee to make a formal 
presentation or to answer questions from the Committee 
members with regard to the inquiry. Attendance at a Com- 
mittee meeting shall be at the expense of the inquirer. The 
inquirer's attendance or lack of attendance at a meeting 



173 



2007 SECTION IV 



shall not be a basis for acceptance or rejection of the inquiry 
by the Committee. 



1-300 



CODE REVISIONS OR ADDITIONS 



Requests for Code revisions or additions shall provide 
the following: 

(a) Proposed Revisions or Additions. For revisions, 
identify the rules of the Code that require revision and 
submit a copy of the appropriate rules as they appear in the 
Code, marked up with the proposed revision. For additions, 
provide the recommended wording referenced to the 
existing Code rules. 

(b) Statement of Need. Provide a brief explanation of 
the need for the revision or addition. 

(c) Background Information. Provide background infor- 
mation to support the revision or addition, including any 
data or changes in technology that form the basis for the 
request that will allow the Committee to adequately evalu- 
ate the proposed revision or addition. Sketches, tables, 
figures, and graphs should be submitted as appropriate. 
When applicable, identify any pertinent paragraph in the 
Code that would be affected by the revision or addition 
and identify paragraphs in the Code that reference the 
paragraphs that are to be revised or added. 



1-400 



CODE CASES 



Requests for Code Cases shall provide a Statement of 
Need and Background Information similar to that defined 
in l-300-3(b) and l-300-3(c), respectively, for Code revi- 
sions or additions. The urgency of the Code Case (e.g., 
project underway or imminent, new procedure, etc.) must 
be defined and it must be confirmed that the request is in 
connection with equipment that will be ASME stamped, 
with the exception of Section XI applications. The pro- 
posed Code Case should identify the Code Section and 
Division, and be written as a Question and a Reply in the 
same format as existing Code Cases. Requests for Code 
Cases should also indicate the applicable Code Editions 
and Addenda to which the proposed Code Case applies. 



1-500 



CODE INTERPRETATIONS 



(a) Requests for Code Interpretations shall provide the 
following: 

(1) Inquiry. Provide a condensed and precise ques- 
tion, omitting superfluous background information and, 



when possible, composed in such a way that a "yes" or a 
"no" Reply, with brief provisos if needed, is acceptable. 
The question should be technically and editorially correct. 

(2) Reply. Provide a proposed Reply that will clearly 
and concisely answer the Inquiry question. Preferably, the 
Reply should be "yes" or "no," with brief provisos if 
needed. 

(3) Background Information. Provide any back- 
ground information that will assist the Committee in under- 
standing the proposed Inquiry and Reply. 

(b) Requests for Code Interpretations must be limited 
to an interpretation of a particular requirement in the Code 
or a Code Case. The Committee cannot consider consulting 
type requests such as the following: 

(1) a review of calculations, design drawings, weld- 
ing qualifications, or descriptions of equipment or parts to 
determine compliance with Code requirements 

(2) a request for assistance in performing any Code- 
prescribed functions relating to, but not limited to, material 
selection, designs, calculations, fabrication, inspection, 
pressure testing, or installation 

(3) a request seeking the rationale for Code require- 
ments 



1-600 



SUBMITTALS 



Submittals to and responses from the Committee shall 
meet the following: 

(a) Submittal. Inquiries from Code users shall be in 
English and preferably be submitted in typewritten form; 
however, legible handwritten inquiries will also be consid- 
ered. They shall include the name, address, telephone num- 
ber, fax number, and e-mail address, if available, of the 
inquirer and be mailed to the following address: 

Secretary 

ASME Boiler and Pressure Vessel Committee 
Three Park Avenue 
New York, NY 10016-5990 
As an alternative, inquiries may be submitted via e-mail 
to: SecretaryBPV@asme.org. 

(b) Response. The Secretary of the ASME Boiler and 
Pressure Vessel Committee or of the appropriate Subcom- 
mittee shall acknowledge receipt of each properly prepared 
inquiry and shall provide a written response to the inquirer 
upon completion of the requested action by the Code Com- 
mittee. 



174 



2007 SECTION IV 



MANDATORY APPENDIX 2 

CODES, STANDARDS, AND 

SPECIFICATIONS REFERENCED IN TEXT 



2-100 



REFERENCE STANDARDS 



Specific editions of standards incorporated in this Code 
are shown in Table 2-100. It is not practical to refer to a 
specific edition of each standard throughout the Code text, 
so edition references are centralized here. Table 2-100 will 
be revised at intervals and reissued as needed. 



2-200 



ORGANIZATIONS 



Listed below are the names, acronyms, and addresses 
of specific organizations referred to in this Code. 

American National Standards Institute (ANSI), 25 West 
43rd Street, New York, NY 10036 



American Society for Testing and Materials (ASTM), 100 
Barr Harbor Drive, West Conshohocken, PA 19428 

American Society of Heating, Refrigerating and Air Condi- 
tioning Engineers (ASHRAE), 1791 Tullie Circle, NE, 
Atlanta, GA 30329 

CSA International (CSA), 178 Rexdale Boulevard, 
Toronto, Ontario, Canada M9W 1R3; 8501 East Pleasant 
Valley Road, Cleveland, OH 44131 

National Fire Protection Association International (NFPA), 
1 Batterymarch Park, Quincy, MA 02269 

National Sanitation Foundation International (NSFI), 789 
Dixboro Road, Ann Arbor, MI 48113 

Underwriters Laboratories, Inc. (UL), 333 Pfingsten Road, 
Northbrook, IL 60062 



TABLE 2-100 
CODES, STANDARDS, AND SPECIFICATIONS REFERENCED IN TEXT 



B16. 1-1989 

B16.5-1988 

B16.9-1986 

B16.11-1991 

B16.15-1985 

B16. 24-1991 

B16.28-1986 

B16.42-1987 

QAI-1 



PTC 25-2001 



American National Standards 

Cast Iron Pipe Flanges and Flanged Fittings 

Pipe Flanges and Flanged Fittings 

Factory- Made Wrought Steel Buttwelding Fittings 

Forged Fittings, Socket Welding and Threaded 

Cast Bronze Threaded Fittings 

Cast Copper Alloy Pipe Flanges and Flanged Fittings 

Wrought Steel Buttwelding Short Radius Elbows and Returns 

Ductile Iron Pipe Flanges and Flanged Fittings 

Qualifications for Authorized Inspection 

ASME Performance Test Code 

Pressure Relief Devices 



National Sanitation Foundation International (NSFI) Standard 

ANSI/NSFI 14-1990 Plastic Piping Components and Related Materials 



UL 969-1995 



Underwriters Laboratories Standard for Safety 

Marking and Labeling Systems 



GENERAL NOTE: The issue date, shown immediately following the hyphen after the number of the standard, 
is the effective date of issue (edition) of the standard. 



175 



2007 SECTION IV 



MANDATORY APPENDIX 3 

ADHESIVE ATTACHMENT OF 

NAMEPLATES TO CASING 



3-100 



SCOPE 



The rules in Appendix 3 cover minimum requirements 
for nameplates and for the use of adhesive systems for the 
attachment of nameplates to casing, limited to 

(a) the use of pressure-sensitive acrylic adhesives preap- 
plied by the nameplate manufacturer and protected with a 
moisture stable release liner 

(b) use of the preapplied adhesive within 2 years of its 
application 

(c) use of an application procedure qualified as outlined 
in 3-101 



3-101 NAMEPLATE APPLICATION 

PROCEDURE QUALIFICATION 

(a) Each nameplate manufacturer's construction shall 
be qualified in accordance with ANSI/UL 969, Marking 
and Labeling Systems, for a surface temperature rating 
greater than that achieved on the surface of the casing in 
the area where the nameplate is applied during operation. 



The exposure conditions shall be for high humidity or 
occasional exposure to water. In addition if the boiler or 
water heater is designed and marked for outdoor installa- 
tion, indoor-outdoor qualification shall be obtained with a 
cold box temperature of -40°F (-40°C). 

(b) Each lot or package of nameplates shall be marked 
with the adhesive application date. 

(c) The manufacturer's quality control system shall 
define that written procedures, acceptable to the Authorized 
Inspector (or ASME Designee for cast iron boilers), for 
the application of adhesive backed nameplates shall be 
prepared and qualified. The application procedure qualifi- 
cation shall include the following essential variables: 

(1) each nameplate manufacturer's material and con- 
struction, including thickness range, UL File No., and rated 
substrate temperature(s) and finish 

(2) the maximum temperature achieved on the surface 
of the casing in the area at which the nameplate is applied 

(3) cleaning requirements for the casing surface 

(4) application temperature range and pressure tech- 
nique 



176 



2007 SECTION IV 



MANDATORY APPENDIX 5 
VACUUM BOILERS 



5-100 



SCOPE 



Section IV Rules permit a boiler to operate with internal 
pressure or with a vacuum. Rules in this Appendix cover 
the minimum requirements for the design, fabrication, and 
inspection of a boiler for vacuum operation only. Exemp- 
tions from certain Section IV requirements are provided. 
All other requirements of Section IV shall be met. 



5-200 MAXIMUM PRESSURE AND 

TEMPERATURE 

(a) Maximum Allowable Working Pressure. The boiler 
shall be designed for 15 psi vacuum (100 kPa vacuum) [0 
psi (0 kPa)]. This value shall be used in all calculations, 
in lieu of the requirements of HG-300(a). 

(b) Maximum temperature shall not exceed 210°F 
(99°C). 



5-300 



DESIGN PARAMETERS 



(a) The thickness of cylindrical shells under external 
pressure shall be calculated in accordance with HG-312, 
except that, when boilers are designed for noncorrosive 
service at a maximum pressure difference between outside 
and inside of 15 psi (100 kPa), the thickness shall be not 
less than V 8 in. (3 mm). 

(b) Rectangular boilers under external pressure shall 
have thicknesses calculated in accordance with Appendix 
13-8 and 13-9 of Section VIII, Division 1 . For noncorrosive 
service only, the thickness shall be not less than \ in. 
(3 mm). 

(c) Stays in compression shall meet the requirements 
of the following: 



l/r < 50 



where 



/ = length 

r = radius of gyration 

(d) The furnace thickness shall be calculated in accor- 
dance with HG-301, using 15 psi (100 kPa) design pressure. 
For noncorrosive service only, the thickness shall be not 
less than !/ 8 in. (3 mm). 



(e) Head thickness shall be calculated in accordance 
with HG-305, HG-306, or HG-307, using 15 psi (100 kPa) 
design pressure, except that, when boilers are designed for 
noncorrosive service at a maximum pressure difference 
between outside and inside of 15 psi (100 kPa), the thick- 
ness shall be not less than % in. (3 mm). 

(f) Tube thickness shall be calculated in accordance with 
HG-315. 

(g) As an alternative to the calculations in items (a) 
through (f), the vessel may be 

(1) designed and constructed to Code requirements 
for an internal pressure of 30 psig (200 kPa) using the 
proof test requirements of HG-501 or HG-502. However, 
no external pressure rating may be shown with the Code 
stamping unless Code requirements for external pressure 
are met (see HG-503). 

(2) designed and constructed as a vacuum vessel for 
an external pressure of 15 psia (100 kPa) using the proof 
test requirements of HG-503. 



5-400 



WELDING 



(a) Joint Efficiency. No factor has to be used for parts 
designed for external pressure (X = 1). For the furnace 
joint, efficiencies shall be in accordance with HW-702. 

(b) Corner or tee joints shall be in accordance with 
HW-701.3. 

(c) Attachment welds shall be in accordance with 
HW-731. 

(d) Welding Qualifications shall be in accordance with 
ASME Section IX. 



5-500 



ALTERNATIVE TO HYDROTEST 



A helium leak test, conducted at the maximum vacuum 
to which the boiler will be exposed, may be used in lieu 
of the hydrostatic test requirements specified in HG-510. 
This test shall be witnessed by the authorized inspector. 
The test shall be conducted in accordance with Section V, 
Article 10, Appendix IV or V. Maximum acceptable leak- 
age rate shall be as follows: 



177 



2007 SECTION IV 



Appendix 



IV — Detector Probe 

V — Tracer Probe 
V — Hood 



Maximum Acceptable Leakage Rate 
(std cm 3 /sec) 

1 x 10 -4 
1 x 10 -5 
1 x 10 -6 



5-600 INSTRUMENTS, FITTINGS, AND 

CONTROLS 

Vacuum boilers shall be provided with instruments, fit- 
tings, and controls in accordance with Articles 6 and 7 of 
Part HG, but they are exempt from the following require- 
ments if pressure and temperature controls are provided 
as described in (a), (b), and (c) below: 

Paragraph Title 



HG-603 


Gauge Glass 


HG-604 


Water Column 


HG-605 


Pressure Control (second control only) 


HG-606 


Low Water Cut-Off 


HG-703.2 


Return Pipe Connection 


HG-705 


Feedwater Connection 


HG-715 


Blowoff and Drain Valves 



These exemptions are applicable only when the follow- 
ing devices are installed: 

(a) Pressure Control. A pressure control that interrupts 
the burner operation in response to boiler pressure, and is 
set at 2.5 psig vacuum (12.2 psia) (17 kPa). 

(b) Temperature Control. Two temperature controls 
responsive to boiler temperature that can interrupt burner 
operation, one shall operate at a temperature below 210°F 
(99°C), and the other shall prevent the temperature from 
exceeding 210°F (99°C) with no automatic recycle. The 
use of a fusible plug to perform the second of these two 
functions is permissible. 

(c) Safety Valve. A safety valve without a test lever, set 
at 7.1 psig (22 psia) (49 kPa gage) maximum pressure and 
sized in accordance with HG-400. 



5-700 



INSPECTION OPENINGS 



Heat exchanger coil openings may be used to satisfy the 
requirements for inspection and access. 



178 



2007 SECTION IV 



MANDATORY APPENDIX 6 
STANDARD UNITS FOR USE IN EQUATIONS 



TABLE 6-1 
STANDARD UNITS FOR USE IN EQUATIONS 



Quantity 



U.S. Customary Units 



SI Units 



Linear dimensions (e.g., length, height, thickness, radius, diameter) 

Area 

Volume 

Section modulus 

Moment of inertia of section 

Mass (weight) 

Force (load) 

Bending moment 

Pressure, stress, stress intensity, and modulus of elasticity 

Energy (e.g., Charpy impact values) 

Temperature 

Absolute temperature 

Fracture toughness 

Angle 

Boiler capacity 



inches (in.) 

square inches (in. 2 ) 

cubic inches (in. 3 ) 

cubic inches (in. 3 ) 

inches 4 (in. 4 ) 

pounds mass (Ibm) 

pounds force (Ibf) 

inch-pounds (in. -lb) 

pounds per square inch (psi) 

foot-pounds (ft-lb) 

degrees Fahrenheit (°F) 

Rankine (R) 

ksi square root inches (ksiTrnT 

degrees or radians 

Btu/hr 



millimeters (mm) 
square millimeters (mm 2 ) 
cubic millimeters (mm 3 ) 
cubic millimeters (mm 3 ) 
millimeters 4 (mm 4 ) 
kilograms (kg) 
newtons (N) 

newton-millimeters (N-mm) 
megapascals (MPa) 
joules (J) 

degrees Celsius (°C) 
kelvin (K) 

MPa square root meters (IV 
degrees or radians 
watts (W) 



Pa^/m) 



179 



2007 SECTION IV 



APPENDICES 



NONMANDATORY APPENDIX B 

METHOD OF CHECKING SAFETY VALVE AND 

SAFETY RELIEF VALVE CAPACITY BY MEASURING 

MAXIMUM AMOUNT OF FUEL THAT CAN BE BURNED 



B-100 



PROCEDURE 



The maximum quantity of fuel C that can be burned per 
hour at the time of maximum forcing is determined by a 
test. The maximum number of heat units per hour, or CH, 
is then determined, using the values of H given in B-102. 
The weight of steam generated per hour is found by the 
formula: 
(U.S. Customary Units) 

C x H x 0.75 



W = 



1,000 



(SI Units) 



W = 



C x H x 0.75 
2 326 



where 

C = total weight or volume of fuel burned /hr at time 

of maximum forcing, lb or ft 3 
H = heat of combustion of fuel, Btu/lb or Btu/ft 3 (see 

B-102) 
W = weight of steam generated/hr, lb 
The sum of the safety valve capacities marked on the 
valves shall be equal to or greater than W. 



B-101 



EXAMPLES 



Example 1. A boiler at the time of maximum forcing 
uses 2,150 lb of Illinois coal/hr of 12,100 Btu/lb. 

C X H = 2,150 x 12,100 = 26,015,000 

W = (C x H x 0.75) -h 1,000 = 19,511 

Example 2. Wood shavings of heat of combustion of 
6,400 Btu/lb are burned under a boiler at the maximum 
rate of 2,000 lb/hr. 

C x H = 2,000 x 6,400 = 12,800,000 

W = (C X H x 0.75) -5- 1,000 = 9,600 



Example 3. An oil-fired boiler at maximum forcing 
uses 1,000 lb of crude oil (Texas) /hr. 

C x H = 1,000 x 18,500 = 18,500,000 

W = (C X H x 0.75) + 1,000 = 13,875 

Example 4. A boiler fired with natural gas consumes 
3,000 ft 3 /hr. 

C x H = 3,000 x 960 = 2,880,000 

W = (C x H x 0.75) -5- 1,000 = 2,160 



B-102 



HEATS OF COMBUSTION OF FUELS 



For the purpose of checking the safety valve capacity 
as described in B-100, the following values of heats of 
combustion of various fuels may be used: 



Material 



Semibituminous coal 

Anthracite 

Screenings 

Coke 

Wood, hard or soft, kiln dried 

Wood, hard or soft, air dried 

Wood shavings 

Peat, air dried, 25% moisture 

Lignite 

Kerosene 

Petroleum, crude oil, Pennsylvania 

Petroleum, crude oil, Texas 



Material 



Natural gas 
Blast-furnace gas 
Producer gas 
Water gas, uncarbureted 



H = Btu/lb 

14,500 

13,700 

12,500 

13,500 

7,700 

6,200 

6,400 

7,500 
10,000 
20,000 
20,700 
18,500 

H = Btu/ft 3 

960 
100 
150 
290 



180 



2007 SECTION IV 



NONMANDATORY APPENDIX C 

EXAMPLES OF METHOD OF CALCULATING A 

WELDED RING REINFORCED FURNACE 



C-100 FOR A STEAM OR HOT WATER 

BOILER 

(a) Design Data [HG-300(a)J. 30 psi pressure (250°F); 
36 in. (D ) O.D.; 15 in. (L) center-to-center distance of 
reinforcing rings. Material is SA-285-C. 

Use formulas from HG-312 where 

D = outside diameter of furnace, in. 

H r = height of stiffening ring, in. 

L = center-to-center distance between two adjacent 
stiffening rings, in. 

P = design pressure, psi (30 psi min.) (per HG-300) 

T r = thickness of stiffening ring, in. 

t = wall thickness of furnace, in. 

(b) Selection of t and L (First Trial). Assume 
t = !/ 4 in. and L = 15 in. 

L/D = 15/36 = 0.417, D lt = 36/0.25 = 144 

Temperature: 500°F [see HG-312.1(b)] 

Factor A = 0.0025 (from Fig. G, Subpart 3 of Section 
H, Part D) 

Factor B = 12,000 (from Fig. CS-2, Subpart 3 of Section 
II, Part D) 



Pn = 



B 



D„/t 



12,000 
144 



= 83 psi 



(c) Selection ofT r and H r (First Trial) [HG-312 .4(b)) '. 
Assume 

T r = 5 /i6 in. and H r = 1.5 in. 
, = 03125 12 X 153 = 0.0879 in.* 

A s = 0.3125 X 1.5 = 0.469 in. 2 

(d) Determination of I s (First Trial) 



Factor B = 



PD n 



30 x 36 



A s n ^ c 0.469 

t+ i: °- 25 + -ir 



= 3,840 



From Fig. CS-2, 



/< = 



DSL \t + -?\A 



14 



36 2 x 15 [0.25 + ^yjH 0.00028 
"14: 



= 0.109 in. 4 

Since I s is greater than / (0.0879 in. 4 ), the assumed 
reinforcing ring is not acceptable. (A ring with a greater 
/ must be selected or L must be reduced.) 

(e) Selection of T r and H r (Second Trial). Assume 

T r = 0.3125 in., H r = 2.5 in., and L = 15 in. 
H r 2.5 



/ = 



T r 0.3125 



0.3125 x 2.5 J 
12 



= 8.0 



= 0.407 in. 4 



A s = 0.3125 x 2.5 = 0.781 in. 2 
(f) Determination of I s (Second Trial) 



30 x 36 
Factor B = ^^r = 3,575 



0.25 + 



0.781 
15 



From Fig. CS-2, 



Factor 4 = 0.00026 



/, = 



36 2 x 15 |0.25 + ^-| 0.00026 



14 



Factor^ = 0.00028 



= 0.109 in. 4 

Since / (0.407 in. 4 ) is greater than I s , the assumed rein- 
forcing ring is acceptable. 



181 



2007 SECTION IV 



C-101 



FOR A HOT WATER BOILER 



(a) Design Data. 100 psi working pressure (250°F); 
30 in. (D ) O.D.; 30 in. (L) center-to-center distance of 
reinforcing rings. Material is SA-285-C. 

Use formulas from HG-312 and same notation as in 
C- 100(a). 

( b) Selection of t and L (First Trial). Assume 
t = V 2 in. and L = 30 in. 

L/D = 30/30 = 1 and D /t = 30/0.500 = 60 
Temperature: 500°F [see HG-312. 1(b)] 
Factor A = 0.003 (from Fig. G) 
Factor B = 12,300 (from Fig. CS-2) 



P. = 



B 



12,300 



= 205 psi 



D /t 60 

(c) Selection of T r and H r (First Trial). Assume 

T r = 3 / 8 in. and H r = 2.25 in. 

0.375 x 2.25 3 4 

/ = — = 0.356 in. 

A s = 0.375 x 2.25 = 0.843 in. 2 

(d) Determination of I s (First Trial) 
PD 



Factor B = 



t + 



100 x 30 



0.500 + 



0.843 
30 



Since I s is greater than / (0.356 in. 4 ), the assumed rein- 
forcing ring is not acceptable. (A ring with a greater / must 
be selected or L must be reduced.) 

(e) Selection of L (Second Trial). Assume 

L = 22 in., T r = \ in., and H = 2.25 in. 



H r 2.25 



0.375 



= 6.0 



L/D = H = 0.734 



DJt = 



30 
0.500 



= 60 



(f) Determination qfl s (Second Trial). From Fig. CS-2, 
Factor B = 13,250 

P a = 13,250/60 = 221 psi 

/ = 0.356 in. 4 (as above) 
A s = 0.843 in. 2 (as above) 



Fac,o, B = 10 ° X A°. - 5,573 



0.500 + 



0.843 

22 



From Fig. CS-2, 



= 5,681 



Factor A = 0.00042 



L = 



D 2 L\t + ^)A 



14 



0.843 \ 
30^ x 30 10.50 + -Tq- |(0.00042) 



14 



= 0.428 in. 4 



From Fig. CS-2, 



Factor A = 0.00041 



/, = 



30 2 x 22 (0.500 + 0.843/22) 0.00041 
14 



= 0.312 in. 4 

Since I s is less than / (0.356 in. 4 ), the assumed reinforcing 
ring is acceptable. 



182 



2007 SECTION IV 



NONMANDATORY APPENDIX D 

EXAMPLES OF METHODS OF COMPUTATION 

OF OPENINGS IN BOILER SHELLS 



D-100 



PAD REINFORCED OPENING 



(a) Design Data. A boiler shell has a 6 in. connection 
as shown in Fig. D-100. The shell has an inside diameter 
of 60 in., a thickness of %(, in. and a working pressure of 
160 psi. The shell and pad material are in accordance with 
SA-285 Grade C. 

(b) Wall Thickness Required (See HG-301) 



t r = 



P X R 



S x E- 0.6P 



160 x 30 



= 0.440 in. 



11,000 X 1.0-0.6 X 160 

(c) Size of Welds Required (See HW-731) 
Inner fillet weld = 1.41 x 0.7 x t r = w x 

wi = 1.41 x 0.7 x 0.440 = 0.434 in. 
Outer fillet weld = 1.41 x 0.5 x t r = w 2 

w 2 = 1.41 X 0.5 x 0.440 = 0.310 in. 

A \ in. inner fillet weld and a \^ in. outer fillet weld 
meet these minimum requirements. 

(d) Area of Reinforcement Required (See HG-321) 

A = d x t r x F 

= 7.50 X 0.440 X 1.0 = 3.300 in. 2 

(e) Area of Reinforcement Provided (See HG-326) 

A x - (Eit- Ft r )d 

= (1.0 x 0.563 - 1.0 x 0.440) 7.5 = 0.922 in. 2 

A 2 = t e (d p -d ) 



= 0.437(12.50 - 6.00) 



-4 3 = 2x l / 2 X)C| 2 + 2x l / 2 x w 2 2 



= 2.841 in. 2 



FIG. D-100 COMPUTATION OF TYPICAL PAD 
REINFORCEMENT 



2d- 



U-c/ n ^i 



w 1-| 



H 



w 2 






= 2 x V 2 x 0.500 2 + 2 x V 2 x 0.437 2 

^ , , * 0.441 in. 2 

Total area provided = 4 2Q4 - n 2 

(f) Load to Be Carried by Welds (See HG-327.2) 
W = (dx t r -A x ) x S 

= (7.50 x 0.440 - 0.922) x 11,000 = 26,160 lb 

(g) Unit Stresses (See HW-730.2) 

Shear in fillet weld = 0.49 x 11,000 

= 5,390 psi = S s 

(h) Strength of Connection Elements 
(1) Inner Weld wi in Shear 



-d x w! x S s = 1.57 x 7.50 x 0.500 x 5,390 



= 31,750 lb 
(2) Outer Weld w 2 in Shear 

jd p x n>2 x S s = 1.57 x 12.50 x 0.437 x 5,390 
= 46,200 lb 



183 



2007 SECTION IV 



FIG. D-101 COMPUTATION OF A TYPICAL 
NOZZLE FITTING 



Limits of 
reinforcement 




D-101 



NOZZLE REINFORCED OPENING 



(a) Design Data. A 4 in. SA-53 schedule 80 pipe is 
welded into a shell as shown in Fig. D-101. The shell has 
an inside diameter of 36 in., a thickness of 7 /i6 in., and 
a working pressure of 160 psi. The shell material is in 
accordance with SA-285 Grade C. 

(b) Wall Thickness Required (See HG-301) 



tr = 



PR 



SE - 0.6P 

_ 160 x 18 

~ 11,000 x 1.0-0.6 x 160 

(c) Nozzle Thickness Required 
PR 



= 0.264 in. 



trn = 



SE - 0.6P 

160 x 1.913 



= 0.032 in. 



9,600 x 1.0 - 0.6 x 160 

(d) Size Weld Required (See HW-731) 

tc = fmin x 0.7 

= 0.337 x 0.7 = 0.236 in. 

(e) Area of Reinforcement Required (See HG-321) 



A = dt r F + 2t n t r F\l-y 



= 3.826 x 0.264 x 1.0 



+ 2 (0.337)(0.264)(1.0) 1 - 



9,600 
11,000 



(f) Area of Reinforcement Provided (See HG-326) 

A, = (E x t - Ft r )d - 2t n (Et - Ft r ) 1 1 - I 1 
= (1.0 x 0.438 - 1.0 x 0.264) 3.826 

- 2.0 x 0.337 (1.0 x 0.438 - 1.0 x 0.264)(0.127) 

= 0.651 in. 2 



= 1.033 in. 2 



M = (t n - t r n ) (5t n + 2t e ) \y 



= (0.337 - 0.032) (5.0 x 0.337 + 2.0 x 0)(0.873) 

= 0.449 in. 2 
A 3 = leg 2 

= 0.337 x 0.337 = 0.114 in. 2 

A T = total reinforcement = 1.214 in. 2 
A T >A (opening is reinforced) 

(g) Load to Be Carried by the Welds (See HG-327.2) 

W = [(d on x t r ) - (2d in - d on )(t - t r )] S(shell) 
= [(4.50 x 0.264) - (2.0 x 3.826 - 4.50) 

x (0.437-0.264)] 11,000 
= 7,035 lb 

(h) Unit Stresses (See HW-730.2) 

Shear in fillet weld = 0.49 x 11,000 

= 5,390 psi = S s 

Tension in groove weld = 0.74 x 11,000 

= 8,140 psi = S t 

Shear in nozzle wall = 0.70 x 11,000 

= 7,700 psi = S n 



184 



2007 SECTION IV 



(i) Strength of Connection Elements (See HW-730.1) 
(1) Fillet Weld in Shear 



-xd on x weld leg x S s = 1.57 X 4.5 x 0.337 x 5,390 



(3) Nozzle Wall Shear 



— x mean nozzle diam. x t n x S n 



= 1.571 X 4.163 x 0.337 x 7,700 



= 12,833 lb 
(2) Groove Weld in Tension 



- x d on x tx S, = 1.57 x 4.5 x 0.437 x 8,140 



= 25,100 lb 



= 16,971 lb 

Possible paths of failure are 

(a) through (1) and (2) above with a strength of 
37,933 lb 

(b) through (1) and (3) above with a strength of 
29,804 lb 

Both paths are stronger than the required strength of 
7,035 lb. 



185 



2007 SECTION IV 



NONMANDATORY APPENDIX E 
TERMINOLOGY 



E-100 



TERMS RELATING TO DESIGN 



action, popping, or pop: the action of a safety or safety 
relief valve when it opens under steam pressure. The disk 
of the valve is designed so that the force of the steam 
lifting the disk is increased when the disk is lifted slightly 
off its seat. The increase in force accelerates the rising 
action of the disk to the wide open position at or near the 
opening pressure. 

blowdown: the difference between the opening and clos- 
ing pressures of a safety or safety relief valve. 

boiler, automatically fired: a boiler equipped with a 
means of introducing heat or of causing fuel, whether solid, 
liquid, gaseous, or electric, to be introduced into the boiler 
or boiler furnace, the means being so regulated by the rate 
of flow, the generating pressure, or temperature of the 
boiler fluid or of a vessel or space being heated as to 
maintain a determined, desired condition within a desig- 
nated tolerance. 

boiler, electric, resistance heating element type: electric 
boilers of the resistance heating element type are either: 

(a) of a design where the electric resistance element is 
directly attached to the external surface of the pressure 
vessel; or 

(b) an immersed type where the electric resistance ele- 
ment is inserted through an opening in the pressure vessel 
so that the element is in direct contact with the water. 

boiler, horizontal-return tubular: a firetube boiler con- 
sisting of a cylindrical shell, with tubes inside the shell 
attached to both end closures. The products of combustion 
pass under the bottom half of the shell and return through 
the tubes. 

boiler, hot water heating: a boiler designed to heat water 
for circulation through an external space heating system. 

boiler, hot water supply: a boiler used to heat water for 
purposes other than space heating. 

boiler, modular: a steam or hot-water heating assembly 
consisting of a grouping of individual boilers called mod- 
ules, intended to be installed as a unit, with a single inlet 
and a single outlet. Modules may be under one jacket or 
may be individually jacketed. 

boiler, steam heating: a boiler designed to convert water 
into steam that is supplied to an external space heating 
system. 



boiler, vacuum: a factory-sealed steam boiler that is 
operated below atmospheric pressure. 

bottom blowojf valve: a valve or cock located in the 
bottom blowoff connection of a boiler that, when opened, 
permits free passage of scale and sediment during the blow- 
off operation. 

column, fluid relief: that piping, connected to the top of 
a hot water heating boiler, which is provided for the thermal 
expansion of the water. It will connect to either an open 
or a closed expansion tank. 

drain valve: a valve or cock located in a boiler connec- 
tion that, when opened, will drain the lowest water space 
practicable. 

electric boiler, submerged electrode type: a submerged 
electrode type electric boiler incorporates a design wherein 
two or more metallic electrodes are directly suspended in 
the boiler water. When a source of electric power is con- 
nected to the electrodes, current will flow between the 
electrodes and through the water, thus raising the tempera- 
ture of the water to produce steam. 

feedwater: water introduced into a boiler during opera- 
tion, includes makeup and return condensate or return 
water. 

flue: passage through which gases pass from the combus- 
tion chamber or furnace to the venting system. 

furnace: that part of a boiler in which combustion of 
fuel takes place or in which primary furnace gases are 
conveyed. 

gases, primary furnace: gases in a zone where the antici- 
pated temperature of the gas exceeds 850°F (450°C). 

joints, swing: threaded, flanged, welded, or brazed pipe 
and fittings so arranged that the piping system that they 
comprise, when connected to a boiler, can expand and 
contract without imposing excessive force on it. 

makeup water: water introduced into the boiler to replace 
that lost or removed from the system. 

pressure, accumulation test: that steam pressure at which 
the capacity of a safety, safety relief, or a relief valve is 
determined. It is 33 ^3% over the steam safety valve set 
pressure and 10% over the safety relief valve set pressure. 

pressure, design: the pressure used in the design of a 
boiler for the purpose of calculating the minimum permissi- 
ble thickness or physical characteristics of the different 
parts of the boiler. 



186 



2007 SECTION IV 



pressure, maximum allowable working: the maximum 
gage pressure permissible in a completed boiler. The 
MAWP of the completed boiler shall be less than or equal 
to the lowest design pressure determined for any of its 
parts. This pressure is based upon either proof tests or 
calculations for every pressure part of the boiler using 
nominal thickness exclusive of allowances for corrosion 
and thickness required for loadings other than pressure. 

pressure, operating: the pressure of a boiler at which 
it normally operates. It shall not exceed the maximum 
allowable working pressure and it is usually kept at a 
suitable level below the setting of the pressure relieving 
devices to prevent their frequent opening. 

rated, officially: a safety or safety relief valve for use 
on a heating boiler that has been capacity rated in accor- 
dance with HG-402. 

siphon: a bent pipe or tube, between a steam pressure 
gage and the steam connection on a boiler, so fabricated 
that it contains a water seal that prevents steam entering 
the Bourdon tube of the gage. 

stress, maximum allowable: the maximum unit stress 
permitted in a given material used under these rules. 

surface, heating, square feet of: that area of the boiler 
surface exposed to the products of combustion. In comput- 
ing the heating surface for the purpose of determining 
the safety or relief valve requirements, only the tubes, 
fireboxes, shells, tubesheets, and the projected area of the 
headers need be considered, except that for vertical firetube 
boilers only that portion of the tube surface up to the middle 
point of the gage glass is to be computed. 

thickness, required: the minimum thickness determined 
by the formulas in this Code. 

tube, fire: a hollow cylinder used for the conveyance of 
gases, flame, or hot air. 

tube, water: a hollow cylinder used for the conveyance 
of liquids. 

valve, safety: an automatic pressure relieving device 
actuated by the static pressure upstream of the valve and 
characterized by full-opening pop action. It is used for gas 
or vapor service. 

valve, safety, lift of: the movement of the disk off the 
seat of a safety, safety relief, or relief valve when the valve 
is opened. It normally refers to the amount of movement 
of the disk off the seat when the valve is discharging at 
rated pressure. 

valve, safety relief: an automatic pressure relieving 
device actuated by the pressure upstream of the valve and 
characterized by opening pop action with further increase 
in lift with an increase in pressure over popping pressure. 

valve, temperature and pressure safety relief: a safety 
relief valve that also incorporates a thermal sensing element 
that is actuated by an upstream water temperature of 210°F 
(99°C) or less. 



water heater: a vessel in which potable water is heated 
by the combustion of fuel, by electricity, or by any other 
source, and withdrawn for external use. 

water heater, lined: a water heater with a corrosion 
resistant lining designed to heat potable water. 

water heater, unlined: a water heater made from corro- 
sion resistant materials designed to heat potable water. 

wet-bottom boiler: any type of boiler that has a stayed 
or self-supporting, partially or fully water-cooled, shell or 
furnace bottom. 



E-101 TERMS RELATING TO WELDING 

arc stud welding: an arc welding process wherein coales- 
cence is produced by heating with an arc drawn between 
a metal stud, or similar part, until the surfaces to be joined 
are properly heated, when they are brought together under 
pressure. Partial shielding may be obtained by the use of 
a ceramic ferrule surrounding the stud. Shielding gas or 
flux may or may not be used. 

arc welding: a group of welding processes wherein 
coalescence is produced by heating with an electric arc or 
arcs, with or without the application of pressure and with 
or without the use of filler metal. 

atomic hydrogen welding: an arc welding process 
wherein coalescence is produced by heating with an electric 
arc maintained between two metal electrodes in an atmo- 
sphere of hydrogen. Shielding is obtained from the hydro- 
gen. Pressure may or may not be used and filler metal may 
or may not be used. 

automatic welding: welding with equipment that per- 
forms the entire welding operation without constant obser- 
vation and adjustment of the controls by an operator. The 
equipment may or may not perform the loading and 
unloading of the work. 

backing: material (metal, weld metal, asbestos, carbon, 
granular flux, etc.) backing up the joint during welding to 
facilitate obtaining a sound weld at the root. 

base metal: the metal to be welded or cut. 

brazing: a group of metal-joining processes wherein 
coalescence is produced by heating to suitable temperatures 
above 800°F (425°C) and by using a nonferrous filler metal, 
having a melting point below that of the base metals. The 
filler metal is distributed between the closely fitted surfaces 
of the joint by capillary attraction. 

butt joint: a joint between two members lying approxi- 
mately in the same plane. 

corner joint: a joint between two members located 
approximately at right angles to each other in the form of 
an L. 

double-welded butt joint: a butt joint welded from 
both sides. 



187 



2007 SECTION IV 



double-welded lap joint: a lap joint in which the over- 
lapped edges of the members to be joined are welded along 
the edges of both members. 

edge joint: a joint between the edges of two or more 
parallel or nearly parallel members. 

filler metal: metal to be added in making a weld. 

fillet weld: a weld of approximately triangular cross 
section joining two surfaces approximately at right angles 
to each other in a lap joint, tee joint, or corner joint. 

flux cored arc welding (FCAW): a gas metal arc welding 
process that produces coalescence of metals by heating 
them with an arc between a continuous filler metal (con- 
sumable) electrode and the work. Shielding is provided by 
a flux contained within the tubular electrode. Additional 
shielding may or may not be obtained from an externally 
supplied gas or gas mixture. 

flux cored arc welding- electro gas (FCAW-EG): a varia- 
tion of the flux cored arc welding process in which molding 
shoes are used to confine the molten weld metal for vertical 
position welding. Additional shielding may or may not be 
obtained from an externally supplied gas or gas mixture. 

flux cored electrode: a composite filler metal electrode 
consisting of a metal tube or other hollow configuration 
containing ingredients to provide such functions as 
shielding atmosphere, deoxidation, arc stabilization, and 
slag formation. Alloying materials may be included in the 
core. External shielding may or may not be used. 

full fillet weld: a fillet weld whose size is equal to the 
thickness of the thinner member joined. 

gas metal arc welding- electro gas (GMAW-EG): a varia- 
tion of the gas metal arc welding process using molding 
shoes to confine the molten weld metal for vertical position 
welding. 

gas tungsten-arc welding: an arc welding process 
wherein coalescence is produced by heating with an electric 
arc between a single tungsten (nonconsumable) electrode 
and the work. Shielding is obtained from a gas or gas 
mixture (which may contain an inert gas). Pressure may 
or may not be used. Filler metal may or may not be used. 
(This process has sometimes been called TIG Welding.) 

gas welding: a group of welding processes wherein 
coalescence is produced by heating with a gas flame or 
flames with or without the application of pressure, and 
with or without the use of filler metal. 

joint efficiency: the efficiency of a welded joint is 
expressed as a numerical (decimal) quantity and is used 
in the design of a joint as a multiplier of the appropriate 
allowable stress taken from Tables HF-300.1 and 
HF-300.2. 

joint penetration: the minimum depth a groove weld 
extends from its face into a joint, exclusive of rein- 
forcement. 

lap joint: a joint between two overlapping members. 



machine welding: welding with equipment that performs 
the welding operation under the observation and control 
of an operator. The equipment may or may not perform 
the loading and unloading of the work. 

manual welding: welding wherein the entire welding 
operation is performed and controlled by hand. 

oxyacetylene welding: a gas welding process wherein 
coalescence is produced by heating with a gas flame or 
flames obtained from the combustion of acetylene with 
oxygen, with or without the application of pressure and 
with or without the use of filler metal. 

oxygen cutting: a group of cutting processes wherein 
the severing of metals is affected by means of the chemical 
reaction of oxygen with the base metal at elevated tempera- 
tures. In the case of oxidation resistant metals, the reaction 
is facilitated by use of a flux or metal powder. 

oxyhydrogen welding: a gas welding process wherein 
coalescence is produced by heating with a gas flame or 
flames obtained from the combustion of hydrogen with 
oxygen, without the application of pressure and with or 
without the use of filler metal. 

plasma arc welding: a gas tungsten arc welding process 
wherein coalescence is produced by heating with a con- 
stricted arc between an electrode and workpiece (trans- 
ferred arc) or the electrode and the constricting nozzle 
(nontransferred arc). Shielding is obtained from hot ionized 
gas issuing from the orifice that may be supplemented by 
an auxiliary source of shielding gas. Shielding gas may be 
an inert gas or a mixture of gases, pressure may or may 
not be used, and filler metal may or may not be used. 

pressure gas welding: a gas welding process wherein 
coalescence is produced simultaneously over the entire 
area of abutting surfaces, by heating with a gas flame or 
flames obtained from combustion of hydrogen with oxy- 
gen, without the application of pressure, and with or with- 
out the use of filler metal. 

pressure welding: any welding process or method 
wherein pressure is used to complete the weld. 

projection welding (PW): a resistance welding process 
that produces coalesence by the heat obtained from the 
resistance of the flow of welding current. The resulting 
welds are localized at predetermined points by projections, 
embossments, or intersections. The metals to be joined lap 
over each other. 

reinforcement of weld: weld metal on the face of a 
groove weld in excess of the metal necessary for the speci- 
fied weld size. 

resistance seam welding (RSEW): a resistance welding 
process that produces coalesence of overlapped parts at 
the faying surfaces progessively along the length of a joint. 
The weld may be made with overlapping nuggets, a contin- 
uous weld nugget, or by forging the joint as it is heated 
to the welding temperature by resistance to the flow of 
welding current. 



2007 SECTION IV 



resistance spot welding (RSW): a resistance welding 
process that produces coalesence at the faying surfaces of 
overlapped parts by the heat obtained from resistance of 
the work to the flow of welding current in a circuit of 
which the work is a part, and by the application of pressure. 

resistance stud welding: a resistance welding process 
wherein coalescence is produced by the heat obtained from 
resistance to electric current at the interface between the 
stud and the work piece, until the surfaces to be joined are 
properly heated, when they are brought together under 
pressure. 

resistance welding (RW): a group of welding processes 
that produces coalescence of overlapping faying surfaces 
with the heat obtained from resistance of the work to the 
flow of current in a circuit of which the work is a part, 
and by the application of pressure. 

seal weld: any weld used primarily to obtain tightness. 

semiautomatic arc welding: arc welding with equipment 
that controls only the filler metal feed. The advance of the 
welding is manually controlled. 

shielded metal-arc welding: an arc welding process 
wherein coalescence is produced by heating with an electric 
arc between a covered metal electrode and the work. 
Shielding is obtained from decomposition of the electrode 
covering. Pressure is not used and filler metal is obtained 
from the electrode. 

single-welded butt joints: a butt joint welded from one 
side only. 

single-welded lap joint: a lap joint in which the over- 
lapped edges of the members to be joined are welded along 
the edge of one member. 

size of weld 

(a) groove weld: the joint penetration (depth of chamfer- 
ing plus the root penetration when specified). 

(b) fillet weld 

(1) for equal-leg fillet welds: the leg length of the 
largest isosceles right triangle that can be inscribed within 
the fillet weld cross section. 



(2) for unequal-leg fillet welds: the leg lengths of the 
largest right triangle that can be inscribed within the fillet 
weld cross section. 

submerged arc welding: an arc welding process wherein 
coalescence is produced by heating with an electric arc or 
arcs between a bare metal electrode or electrodes and the 
work. The welding is shielded by a blanket of granular, 
fusible material on the work. Pressure is not used and filler 
metal is obtained from the electrode and sometimes from 
a supplementary welding rod. 

tee joint: a joint between two members located approxi- 
mately at right angles to each other in the form of a T. 

thermit welding: a group of welding processes wherein 
coalescence is produced by heating with superheated liquid 
metal and slag resulting from a chemical reaction between 
a metal oxide and aluminum, with or without the applica- 
tion of pressure. Filler metal, when used, is obtained from 
the liquid metal. 

throat of a fillet weld 

(a) theoretical: the distance from the beginning of the 
root of the joint perpendicular to the hypotenuse of the 
largest right triangle that can be inscribed within the fillet 
weld cross section. 

(b) actual: the shortest distance from the root of a fillet 
weld to its face. 

undercut: a groove melted into the base metal adjacent 
to the toe of a weld and left unfilled by weld metal. 

weld: a localized coalescence of metal wherein coales- 
cence is produced by heating to suitable temperatures, with 
or without the application of pressure and with or without 
the use of filler metal. The filler metal has a melting point 
approximately the same as the base metals. 

weld metal: that portion of a weld that has been melted 
during welding. 

welded joint: a union of two or more members produced 
by the application of a welding process. 

welder: one who is capable of performing a manual or 
semiautomatic welding operation. 

welding operator: one who operates machine or auto- 
matic welding equipment. 



189 



2007 SECTION IV 



NONMANDATORY APPENDIX F 
QUALITY CONTROL SYSTEM 



F-100 



GENERAL 



F-100.1 Quality Control System. The manufacturer or 
assembler shall have and maintain a quality control system 
that will establish that all Code requirements including 
material, design, fabrication, examination (by the manufac- 
turer), and inspection (by the Authorized Inspector) for 
boilers and water heaters constructed primarily of wrought 
materials will be met. The Quality Control System of the 
"HV" Stamp holder shall include duties of a Certified 
Individual, as required by this Section. 

Provided that Code requirements are suitably identified, 
the system may include provisions for satisfying any 
requirements by the manufacturer or user that exceed mini- 
mum Code requirements and may include provisions for 
quality control of non-Code work. In such systems, the 
manufacturer may make changes in parts of the system 
that do not affect the Code requirements without securing 
acceptance by the Authorized Inspector. Before implemen- 
tation, revisions to quality control systems of manufactur- 
ers and assemblers of safety and safety relief valves shall 
have been found acceptable to the ASME Designee if such 
revisions affect Code requirements. 

The system that the manufacturer uses to meet the 
requirements of this Section must be one suitable for his 
own circumstances. The necessary scope and detail of the 
system shall depend upon the complexity of the work per- 
formed and upon the size and complexity of the manufac- 
turer's organization. A written description of the system 
the manufacturer will use to produce a Code item shall be 
available for review. Depending upon the circumstances, 
the description may be brief or voluminous. 

The written description may contain information of a 
proprietary nature relating to the manufacturer's processes. 
Therefore, the Code does not require any distribution of 
this information, except for the Authorized Inspector or 
ASME Designee, as covered by F-202.10. It is intended 
that information learned about the quality control system 
in connection with evaluation will be treated as confidential 
and that all loaned descriptions will be returned to the 
manufacturer upon completion of the evaluation. 



F-202 OUTLINE OF FEATURES TO BE 

INCLUDED IN THE WRITTEN 
DESCRIPTION OF THE QUALITY 
CONTROL SYSTEM 

The following is a guide to some of the features that 
should be covered in the written description of the quality 
control system and that is equally applicable to both shop 
and field work. 

F-202. 1 Authority and Responsibility. The authority 
and responsibility of those in charge of the quality control 
system shall be clearly established. Persons performing 
quality control functions shall have sufficient and well 
defined responsibility, the authority, and the organizational 
freedom to identify quality control problems and to initiate, 
recommend, and provide solutions. 

F-202.2 Organization. An organization chart showing 
the relationship between management and engineering, 
purchasing, manufacturing, field assembling, inspection, 
and quality control, is required to reflect the actual organi- 
zation. The purpose of this chart is to identify and associate 
the various organizational groups with the particular func- 
tion for which they are responsible. The Code does not 
intend to encroach on the manufacturer's right to establish, 
and from time to time, alter whatever form of organization 
the manufacturer considers appropriate for its Code work. 

F-202.3 Drawings, Design Calculations, and Speci- 
fication Control. The manufacturer's or assembler's qual- 
ity control system shall provide procedures that will insure 
that the latest applicable drawings, design calculations, 
specifications, and instructions required by the Code, as 
well as authorized changes, are used for manufacture, 
assembly, examination, inspection, and testing. 

F-202.4 Material Control. The Manufacturer or 
assembler shall include a system of receiving control that 
requires verification that the material received conforms 
to order requirements and that the identification of the 
materials corresponds to the material certifications or mate- 
rial test reports. The system shall ensure that only the 
intended material is used in Code construction. 

F-202.5 Examination and Inspection Program. The 

Manufacturer's quality control system shall describe the 



190 



2007 SECTION IV 



fabrication operations, including examinations, sufficiently 
to permit the Authorized Inspector to determine at what 
stages specific inspections are to be performed. 

F-202.6 Correction of Nonconformities. There shall 
be a system agreed upon with the Authorized Inspector 
for correction of nonconformities. A nonconformity condi- 
tion is a condition that does not comply with the applicable 
rules of this Section. Nonconformities must be corrected 
or eliminated in some way before the completed component 
can be considered to comply with this Section. 

F-202.7 Welding or Brazing. The quality control sys- 
tem shall include provisions for indicating that welding or 
brazing conforms to requirements of Section IX as supple- 
mented by this Section. 

F-202.8 Calibration of Measurement and Test 
Equipment. The Manufacturer or assembler shall have a 
system for the calibration of examination, measuring, and 
testing of equipment used in fulfillment of requirements 
of this Section. 

F-202.9 Sample Forms. The forms used in the quality 
control system and any detailed procedures for their use 
shall be available for review. The written description shall 
make necessary references to these forms. 

F-202.10 Authorized Inspector 

F-202.10.1 The Authorized Inspector is the ASME 
Code Inspector defined in HG-515.3. 



F-202.10.2 The written description of the quality 
control system shall include reference to the Authorized 
Inspector. 

F-202.10.2.1 The Manufacturer shall make avail- 
able to the Authorized Inspector at the Manufacturer's 
plant a copy of the written description of the quality control 
system. 

F-202.10.2.2 The Manufacturer's quality control 
system shall provide for the Authorized Inspector at the 
Manufacturer's plant to have access to all drawings, calcu- 
lations, specifications, procedures, process sheets, repair 
procedures, records, test results, and any other documents 
as necessary for the Authorized Inspector to perform his 
duties in accordance with this Section. The Manufacturer 
may provide such access either to his own files of such 
documents or by providing copies to the Authorized 
Inspector. 

F-202.11 Inspection During Manufacture of Safety 
and Safety Relief Valves. See HG-401.3. 

F-202.12 Certifications. Methods other than written 
signature may be used for indicating certifications, authori- 
zations, and approval where allowed and as described else- 
where in this section. Where other methods are employed, 
controls and safeguards shall be provided and described 
to ensure the integrity of the certification, authorization, 
and approval. 



191 



2007 SECTION IV 



NONMANDATORY APPENDIX H 
LIST OF ABBREVIATIONS AND ADDRESSES 



ANSI American National Standards Institute 

25 West 43rd Street, New York, NY 10036 



ASHRAE American Society of Heating, Refrigerating and 
Air Conditioning Engineers 
1791 Tullie Circle, NE, Atlanta, GA 30329 



ASTM American Society for Testing and Materials 

100 Barr Harbor Drive, West Conshohocken, PA 19428 



CSA CSA International 

178 Rexdale Boulevard, Toronto, Ontario, Canada M9W 1R3; 
8501 East Pleasant Valley Road, Cleveland, OH 44131 

NEC National Electric Code NFPA 70 

National Fire Protection Association International 
1 Batterymarch Park, Quincy, MA 02269 

NSFI National Sanitation Foundation International 

3475 Plymouth Road, Ann Arbor, MI 48113 



UL 



Underwriters Laboratories, Inc. 

333 Pfingsten Road, Northbrook, IL 60062 



192 



2007 SECTION IV 



NONMANDATORY APPENDIX I 

SPECIFICATIONS FOR TEST METHOD FOR WATER 

ABSORPTION OF PLASTICS 




SD-570 



[Identical to ASTM Specification D 570-81 (Reapproved 1988 except for the rounding off of the metric values)] 



1. Scope 

1.1 This test method covers the determination of the 
relative rate of absorption of water by plastics when 
immersed. The test method is intended to apply to the 
testing of all types of plastics, including cast, hot-molded, 
and cold-molded resinous products, and both homogeneous 
and laminated plastics in rod and tube form and in sheets 
0.13 mm (0.005 in.) or greater in thickness. 

1.2 The values stated in SI units are to be regarded 
as the standard. The values stated in parentheses are for 
information purposes only. 

1.3 This standard may involve hazardous materials, 
operations, and equipment. This standard does not purport 
to address all of the safety problems associated with its 
use. It is the responsibility of the user of this standard 
to establish appropriate safety and health practices and 
determine the applicability of regulatory limitations prior 
to use. 



2. Referenced Document 

2.1 ASTM Standard: 
D 647 Design of Molds for Test Specimens of Plastic 
Molding Materials 



3. Significance and Use 

3.1 The test method for rate of water absorption has 
two chief functions: first, as a guide to the proportion of 
water absorbed by a material and consequently, in those 
cases where the relationships between moisture and electri- 
cal or mechanical properties, dimensions, or appearance 
have been determined, as a guide to the effects of exposure 
to water or humid conditions on such properties; and sec- 
ond, as a control test on the uniformity of a product. This 



second function is particularly applicable to sheet, rod, and 
tube arms when the test is made on the finished product. 

3.2 Comparison of water absorption values of various 
plastics can be made on the basis of values obtained in 
accordance with 7.1 and 7.4. 

3.3 The moisture content of a plastic is very intimately 
related to such properties as electrical insulation resistance, 
dielectric losses, mechanical strength, appearance, and 
dimensions. The effect upon these properties of change in 
moisture content due to water absorption depends largely 
on the type of exposure (by immersion in water or by 
exposure to high humidity), shape of the part, and inherent 
properties of the plastic. With nonhomogeneous materials, 
such as laminated forms, the rate of water absorption may 
be widely different through each edge and surface. Even 
for otherwise homogeneous materials, it may be slightly 
greater through cut edges than through molded surfaces. 
Consequently, attempts to correlate water absorption with 
the surface area must generally be limited to closely related 
materials and to similarly shaped specimens: For materials 
of widely varying density, relation between water-absorp- 
tion values on a volume as well as a weight basis may 
need to be considered. 

4. Apparatus 

4.1 Balance — An analytical balance capable of reading 
0.0001 g. 

4.2 Oven, capable of maintaining uniform temperatures 
of 50 ± 3°C (122 ± 5.4°F) and of 105 to 110°C (221 to 
230°F). 

5. Test Specimen 

5.1 The test specimen for molded plastics shall be in 
the form of a disk 50 mm (2 in.) in diameter and 3 mm 



193 



2007 SECTION IV 



(Vg in.) in thickness (Note 1). Permissible variations in 
thickness are ±0.18 mm (±0.007 in.) for hot-molded and 
±0.30 mm (±0.012 in.) for cold-molded or cast materials. 

NOTE 1 : The disk mold prescribed in the Molds for Disk Test Specimens 
Section of Practice D 647 is suitable for molding disk test specimens of 
thermosetting materials but not thermoplastic materials. 

5.2 The test specimen for sheets shall be in the form 
of a bar 75 mm (3 in.) long by 25 mm (1 in.) wide by the 
thickness of the material. When comparison of absorption 
values with molded plastics is desired, specimens 3 mm 
(Vg in.) thick should be used. Permissible variations in 
thickness shall be 0.20 mm (±0.008 in.) except for asbestos- 
fabric-base phenolic laminated materials or other materials 
which have greater standard commercial tolerances. 

5.3 The test specimen for rods shall be 25 mm (1 in.) 
long for rods 25 mm (1 in.) in diameter or under, and 
13 mm (V 2 in.) long for larger-diameter rods. The diameter 
of the specimen shall be the diameter of the finished rod. 

5.4 The test specimen for tubes less than 75 mm (3 in.) 
in inside diameter shall be the full section of the tube and 
25 mm (1 in.) long. For tubes 75 mm (3 in.) or more in 
inside diameter, a rectangular specimen shall be cut 75 mm 
(3 in.) in length in the circumferential direction of the tube 
and 25 mm (1 in.) in width lengthwise of the tube. 

5.5 The test specimens for sheets, rods, and tubes shall 
be machined, sawed, or sheared from the sample so as to 
have smooth edges free from cracks. The cut edges shall 
be made smooth by finishing with No. or finer sandpaper 
or emery cloth. Sawing, machining, and sandpapering oper- 
ations shall be slow enough so that the material is not 
heated appreciably. 

NOTE 2: If there is any oil on the surface of the specimen when received 
or as a result of machining operations, wash the specimen with a cloth 
wet with gasoline to remove oil, wipe with a dry cloth, and allow to 
stand in air for 2 h to permit evaporation of the gasoline. If gasoline 
attacks the plastic, use some suitable solvent or detergent that will evapo- 
rate within the 2-h period. 

5.6 The dimensions listed in the following table for 
the various specimens shall be measured to the nearest 
0.025 mm (0.001 in.). Dimensions not listed shall be mea- 
sured within 0.8 mm (±}/yi in.). 

Type of Dimensions to be Measured to the 

Specimen Nearest 0.025 mm (0.001 in.) 



Molded disk 


thickness 


Sheet 


thickness 


Rod 


length and diameter 


Tube 


inside and outside diameter, and 




wall thickness 



6. Conditioning 

6.1 Three specimens shall be conditioned as follows: 
6.1.1 Specimens of materials whose water-absorp- 
tion value would be appreciably affected by temperatures 



in the neighborhood of 110°C (230°F), shall be dried in 
an oven for 24 h at 50 ± 3°C (122 ± 5.4°F), cooled in a 
desiccator, and immediately weighed to the nearest 0.001 g. 

NOTE 3: If a static charge interferes with the weighing, lightly rub the 
surface of the specimens with a grounded conductor. 

6.1.2 Specimens of materials, such as phenolic lami- 
nated plastics and other products whose water-absorption 
value has been shown not to be appreciably affected by 
temperatures up to 110°C (230°F), shall be dried in an 
oven for 1 h at 105 to 110°C (221 to 230°F). 

6.1.3 When data for comparison with absorption val- 
ues for other plastics are desired, the specimens shall be 
dried in an oven for 24 h at 50 ± 3°C (122 ± 5.4°F), cooled 
in a desiccator, and immediately weighed to the nearest 
0.001 g. 



7. Procedure 

7.1 24-h Immersion — The conditioned specimens shall 
be placed in a container of distilled water maintained at a 
temperature of 23 ± 1°C (73.4 ± 1.8°F), and shall rest on 
edge and be entirely immersed. At the end of 24, +!/ 2 , -0 
h, the specimens shall be removed from the water one at 
a time, all surface water wiped off with a dry cloth, and 
weighed to the nearest 0.001 g immediately. If the speci- 
men is V^ in. (1.5 mm) or less in thickness, it shall be put 
in a weighing bottle immediately after wiping and weighed 
in the bottle. 

7.2 2-h Immersion — For all thicknesses of materials 
having a relatively high rate of absorption, and for thin 
specimens of other materials which may show a significant 
weight increase in 2 h, the specimens shall be tested as 
described in 7.1 except that the time of immersion shall 
be reduced to 120 ± 4 min. 

7.3 Repeated Immersion — A specimen may be weighed 
to the nearest 0.001 g after 2-h immersion, replaced in the 
water, and weighed again after 24 h. 

NOTE 4: In using this method the amount of water absorbed in 24 
h may be less than it would have been had the immersion not been 
interrupted. 

7.4 Long-Term Immersion — To determine the total 
water absorbed when substantially saturated, the condi- 
tioned specimens shall be tested as described in 7.1 except 
that at the end of 24 h they shall be removed from the 
water, wiped free of surface moisture with a dry cloth, 
weighed to the nearest 0.001 g immediately, and then 
replaced in the water. The weighings shall be repeated at 
the end of the first week and every two weeks thereafter 
until the increase in weight per two-week period, as shown 
by three consecutive weighings, averages less than 1 % of 
the total increase in weight, or 5 mg, whichever is greater; 



194 



2007 SECTION IV 



the specimen shall then be considered substantially satu- 
rated. The difference between the substantially saturated 
weight and the dry weight shall be considered as the water 
absorbed when substantially saturated. 

7.5 2-h Boiling Water Immersion — The conditioned 
specimens shall be placed in a container of boiling distilled 
water, and shall be supported on edge and be entirely 
immersed. At the end of 120 ± 4 min, the specimens shall 
be removed from the water and cooled in distilled water 
maintained at room temperature. After 15 ± 1 min, the 
specimens shall be removed from the water, one at a time, 
all surface water removed with a dry cloth, and the speci- 
mens weighed to the nearest 0.001 g immediately. If the 
specimen is V^ in. (1.5 mm) or less in thickness, it shall 
be weighed in a weighing bottle. 

7.6 V 2 -h Boiling Water Immersion — For all thicknesses 
of materials having a relatively high rate of absorption, 
and for thin specimens of other materials which may show 
a significant weight increase in V 2 h the specimens shall 
be tested as described in 7.5, except that the time of immer- 
sion shall be reduced to 30 ± 1 min. 

7.7 Immersion at 120°F (50°C) — The conditioned spec- 
imens shall be tested as described in 7.5, except that the 
time and temperature of immersion shall be 48 ± 1 h and 
50 ± 1°C (122.0 ± 1.8°F), respectively, and cooling in 
water before weighing shall be omitted. 

7.8 When data for comparison with absorption values 
for other plastics are desired, the 24-h immersion procedure 
described in 7.1 and the equilibrium value determined in 
7.4 shall be used. 



9.1.1 Dimensions of the specimens before test, mea- 
sured in accordance with 5.6, and reported to the nearest 
0.001 in., 

9.1.2 Conditioning time and temperature, 

9.1.3 Immersion procedure used, 

9.1.4 Time of immersion (long-term immersion pro- 
cedure only), 

9.1.5 Percentage increase in weight during immer- 
sion, calculated to the nearest 0.01% as follows: 



Increase in weight, % = 



wet wt - conditioned wt 
conditioned wt 



x 100 



9.1.6 Percentage of soluble matter lost during immer- 
sion, if determined, calculated to the nearest 0.01% as 
follows (Note 5): 



Soluble matter lost, % 



conditioned wt - reconditioned wt 
conditioned wt 



x 100 



NOTE 5: When the weight on reconditioning the specimen after immer- 
sion in water exceeds the conditioned weight prior to immersion, report 
"none" under 9.1.6. 

9.1.7 The percentage of water absorbed, which is 
the sum of the values in 9.1.5 and 9.1.6, and 

9.1.8 Any observations as to warping, cracking, or 
change in appearance of the specimens. 



8. Reconditioning 

8.1 When materials are known or suspected to contain 
any appreciable amount of water-soluble ingredients, the 
specimens, after immersion, shall be weighed, and then 
reconditioned for the same time and temperature as used 
in the original drying period. They shall then be cooled in a 
desiccator and immediately reweighed. If the reconditioned 
weight is lower than the conditioned weight, the difference 
shall be considered as water-soluble matter lost during the 
immersion test. For such materials, the water-absorption 
value shall be taken as the sum of the increase in weight 
on immersion and of the weight of the water-soluble matter. 



10. Precision and Bias 

10.1 Precision — An interlaboratory test program was 
carried out using the procedure outlined in 7.1, involving 
three laboratories and three materials. Analysis of this data 
yields the following coefficients of variation (average of 
three replicates). 





Within 


Between 




Laboratories 


Laboratories 


verage absorption above 1% 


2.33% 


4.89% 


(2 materials) 






verage absorption below 0.2% 


9.01% 


16.63% 


(1 material) 







9. Calculation and Report 

9.1 The report shall include the values for each speci- 
men and the average for the three specimens as follows: 



10.2 Bias — No justifiable statement on the bias of this 
test method can be made, since the true value of the prop- 
erty cannot be established by an accepted referee method. 



195 



2007 SECTION IV 



NONMANDATORY APPENDIX K 

GUIDE TO INFORMATION APPEARING ON 

CERTIFICATE OF AUTHORIZATION 



ITEM DESCRIPTION 

© a. The name of the Manufacturer or Assembler. 

b. The full street address, city, state or province, country, and zip code. 

(2) This section describes the scope and limitations, if any, on use of the Code symbol stamps, as 
illustrated below by some examples of scope statements. Field site Certificate of Authorization 
applies to items that are fabricated or assembled at a field site and is not intended to apply to 
items at any shop location. 

H Code Symbol Stamp 

1 . Heating boilers, except cast iron, at the above location only. 

2. Heating boilers, except cast iron, at the above location only. (This authorization includes 
multiple duplicate heating boilers.) 

3. Heating boilers, except cast iron, at the above location. (This authorization does not cover 
welding or brazing.) 

4. Heating boilers, except cast iron, at the above location and field sites controlled by the above 
location. 

5. Heating boilers, cast iron only, at the above location only. (Assembly) 

6. Heating boilers, except cast iron at field sites controlled by the above location only. 

7. Heating boilers, except cast iron, at the above location only. (This authorization includes 
multiple duplicate heating boilers and does not include welding or brazing.) 

8. Heating boilers, cast iron only, at the above location only. (Foundry) 

9. Heating boilers, cast iron only, at the above location only. (Foundry and Assembly) 

10. Heating boilers, cast iron only, at the above location only. (Installation of nameplate only, 
does not include assembly and hydrostatic test.) 

HLW Code Symbol Stamp 

1 . Potable water heaters at the above location only. 

2. Potable water heaters at the above location only. (This authorization includes multiple duplicate 
potable water heaters.) 

3. Potable water heaters at the above location and field sites controlled by the above location. 

4. Potable water heaters at the above location only. (This authorization does not cover welding 
or brazing.) 

5. Potable water storage tanks at the above location only. 

6. Potable water storage tanks at the above location only (This authorization includes multiple 
duplicate potable water storage tanks.) 

7. Potable water storage tanks at the above location and field sites controlled by the above location. 

8. Potable water storage tanks at the above location only. (This authorization does not cover 
welding or brazing.) 

9. Potable water heaters and potable water storage tanks at the above location only. 

196 



2007 SECTION IV 



10. Potable water heaters and potable water storage tanks at the above location only. (This 
authorization includes multiple duplicate potable water heaters and potable water storage 
tanks.) 

11. Potable water heaters and potable water storage tanks at the above location and field sites 
controlled by the above location. 

12. Potable water heaters and potable water storage tanks at the above location only. (This 
authorization does not cover welding or brazing.) 

HV Code Symbol Stamp 

1. Manufacturer of heating boiler safety valves and safety relief valves at the above location only. 

2. Manufacturer of heating boiler safety valves and safety relief valves at the above location only. 
(This authorization does not cover welding or brazing.) 

(?) The date authorization was granted by the Society to use the appropriate Code Symbol Stamp. 

© The date authorization to use the appropriate Code Symbol Stamp will expire. 

(D A unique Certificate number assigned by the Society. 

© Code Symbol granted by the Society, i.e., H Heating Boilers; HLW Water Heaters; and HV Safety 
Valves. 

(7), ® The signature of the current Chair of the Boiler and Pressure Vessel Committee and the Director 
of Accreditation. 



197 



2007 SECTION IV 



FIG. K-l SAMPLE CERTIFICATE OF AUTHORIZATION 



03 
03 



CO 

o 

■ an 

CO 

o 

0) 



SYMBOL 



CERTIFICATE OF 
AUTHORIZATION 



This certificate accredits the named company as authorized to use the indicated 
symbol of the American Society of Mechanical Engineers (ASME) for the scope 
of activity shown below in accordance with the applicable rules of the ASME Boiler 
and Pressure Vessel Code. The use of the Code symbol and thjpruthority granted 



by this Certificate of Authorization are subject to the provis, 
set forth in the application. Any construction stamped with 
been built strictly in accordance with the provisions of 
Pressure Vessel Code. 




COMPANY ® 



1 SCOPE © 






agreement 
hall have 
oiler and 



0) ! 

■■■■ 

o i 

jy3 J AUTHORIZED 

— = EXPIRES ® 



CO 

o 

■ ■MB 

E 

< 

0) 



CERTIFICATE NUMBER 




CHAIRMAN OF THE BOILER 

AND PRESSURE VESSEL COMMITTEE 



DIRECTOR, ASME ACCREDITATION 
AND CERTIFICATION 



198 



2007 SECTION IV 



NONMANDATORY APPENDIX L 

GUIDE TO MANUFACTURER'S 

DATA REPORT FORMS 



INTRODUCTION 



The following pages are a guide for completing the 
Manufacturer's Data Report Forms. Forms and guides are 
keyed in the following manner: 



O Circled numbers refer to the guide for required subject 
material. 



1 . Numbers without circles appearing in the guide material 

identify specific lines on the Manufacturer's Data 

Report Forms. 

Any quantity to which units apply shall be entered on 
the Manufacturer's Data Report with the chosen units. 

Forms appearing in this section may be obtained from 
the ASME Order Department, 22 Law Drive, Box 2300, 
Fairfield, NJ 07007-2300. 



199 



2007 SECTION IV 



INSTRUCTIONS FOR THE PREPARATION OF 

SECTION IV MANUFACTURER'S DATA REPORT FORMS 

Any quantity to which units apply shall be entered on the Manufacturer's Data Report with the chosen units. 



Applies to Form 



Note 



H-2 H-3 H-4 H-5 H-6 HLW-6 HLW-7 HLW-8 No. Instruction: 



X 


X 


X 


X 


X 


X 


X 


X 


X 


X 




X 


X 


X 


X 


X 


X 




X 


X 




X 


X 




X 


X 






X 


X 


X 




X 


X 


X 


X 


X 


X 




X 


X 


X 


X 


X 


X 






X 


X 


X 


X 


X 






X 


X 


X 


X 


X 






X 




X 










X 




X 


X 


X 






X 



X 

XXX 



XXX 
X 



X 



© 

© 
© 

© 
© 



© 
© 

© 

© 
© 

© 



© 
© 
© 
© 

© 
© 

© 
© 

© 
© 

© 
@ 



Name and address of manufacturer (i.e., maker of all components not 

covered by Partial Data Reports). 

Name and address of purchaser and/or owner. 

Name and address of location where unit isto be installed. If not known, 

so indicate (e.g., "not known — built for stock"). 

Show type or model of unit documented by this data report. 

Identification of unit by applicable numbers. If intended for installation 

in Canada, indicate the Canadian design registration number and 

drawing number. 

Year in which fabrication was completed in shop. 

Date (year) of Section IV edition under which boiler or part was 

constructed. 

Issue date of most recent addenda to Section IV under which boiler 

or part was constructed (e.g., "December 1997"). 

Code Case number, if applicable. 

Show quantity and inside dimensions. If more than two shells or 

drums are used, enter data in line 14. 

Show the complete ASME material specification number and grade as 

listed in the appropriate stress allowance table in Section IV (e.g., "SA- 

285-B") Exception: A specification number for a material not identical 

to an ASME Specification may be shown only if such material has been 

approved for Section IV construction by an ASME interpretation case 

ruling and provided the applicable case number is also shown. 

Indicate type of joint(s). 

Show joint efficiency for welded joints. 

Show number of furnaces in boiler. 

Forcylindrical furnaces of the Adamson, ring-reinforced, and combined 

types, show total length only. 

For stayed (firebox) type furnace, complete line 12 also. 

If threaded, show diameter at root of thread. 

Minimum cross-sectional area after deducting for telltale hole. 

Maximum allowable working pressure for the stayed area calculated 

according to the rules contained in Part HG of Section IV. 

Type of stay or brace (e.g., diagonal, gusset, girder, through, etc.). 

Minimum cross-sectional area of the stay or brace multiplied by the 

number of stays or braces supporting the area under consideration. 

See applicable paragraphs and figures in Part HG of Section IV. 

List parts not covered elsewhere on the data report. If insufficient space, 

attach a supplementary sheet. 

Tabulate data for parts listed on line 14. 

Show data for main and auxiliary inlets and outlets, nozzles, inspection 

openings, safety valve openings, drains, and blowoffs. This does not 

apply to small openings for water column, controls, vents, etc. 

Maximum allowable working pressure. 

Show Section IV paragraph that applies to the weakest part of the unit 

as established by calculation or deformation test. 

Boiler heating surface calculated in accordance with HG-403 of Section 

IV. 



200 



2007 SECTION IV 



INSTRUCTIONS FOR THE PREPARATION OF 
SECTION IV MANUFACTURER'S DATA REPORT FORMS (CONT'D) 



Applies to Form 



Note 



H-2 H-3 H-4 H-5 H-6 HLW-6 HLW-7 HLW-8 No. Instruction: 



X ... ... © Hydrostatic pressure applied in accordance with HG-510 and witnessed 

by the Authorized Inspector. 
X X X X ... © To be completed when one or more components comprising the unit 

are furnished by others and certified by the applicable Partial Data 

Report(s). 

XXXXX X X X © The manufacturer's ASME Certificate of Authorization number and date 

of expiration of said authorization. 

XXX. ..X X X X @ This line is to be completed and signed by an authorized representative 

of the manufacturer. 

XXX X X X @ This certificate is to be completed by the Authorized Inspection Agency 

representative who performs the in-shop inspection. 

XXX X X X (34) To determine what goes in this space, you should be guided by the 

following: National Board stamped boilers and pressure vessels: 
After "and state or province" in the certification blocks — if the 
Inspector has a valid Certificate of Competency for the state or province 
where the manufacturer's shop is located, insert the name of that state 
or province. If the manufacturer is located in a non-Code jurisdiction, 
insert the name of the state or province where the inspector took 
his original examination to obtain his National Board Commission, 
provided that Certificate of Competency is still valid. If not, show the 
name of the state or province where he has a valid Certificate of 
Competency authorizing him to make the shop inspection. 
Boilers and pressure vessels stamped only ASME: 
Follow the above procedure. However, in this case do not list any 
National Board Commission number after the inspector's signature at 
the bottom of the block. 

X X X ... ... @) Indicate the data items covered on the applicable form by line numbers. 

X X X ... ... (Si) Indicate by line numbers those items furnished by others and for which 

the applicable Partial Data Reports have been examined. 

XXX. ..X X X X @ The inspector's National Board Commission number and the state or 

province Certificate of Competency number must be shown when the 
boiler is stamped National Board. The inspector shall use his 
jurisdictional Certificate of Competency and National Board 
Commission number on Partial Data Report Forms. If the boiler or 
vessel is not to be registered with the National Board, the inspector 
shall use only his state or province Certificate of Competency number. 

X X ... ... @) The assembler's ASME Certificate of Authorization number and date 

of expiration of said authorization. 

X X ... ... (39) This line to be completed, when applicable, and signed by an authorized 

representative of the organization responsible for field assembly of 
the boiler. 

X X ... ... © This certificate to be completed by the Authorized Inspection Agency 

representative who performs the field assembly inspection. 

X X ... ... © Indicate by line numbers from the applicable form those items 

inspected in the field that were not inspected in the shop. 

XXX X X X © Nominal thickness of plate. 

... X X ... ... @ Minimum thickness after forming. 

... X X ... ... @ Radius on concave side of dish. 

... X X © Shop hydrostatic test, if any, applied to individual part prior to test 

applied to the assembled boiler (see lines 33 and 35). 

... X X © This line for headers not covered as items 7 through 10. It is intended 

primarily for sectional headers on straight tube watertube boilers. 



201 



2007 SECTION IV 



INSTRUCTIONS FOR THE PREPARATION OF 
SECTION IV MANUFACTURER'S DATA REPORT FORMS (CONT'D) 



Applies to Form 



Note 



H-2 H-3 H-4 H-5 H-6 HLW-6 HLW-7 HLW-8 No. Instruction: 





X 


X 




X 


X 




X 


X 




X 


X 




X 






X 


X 




X 


X 
X 
X 


X X 


X 



X 

XXX 









(63) 


X 






© 


X 


X 




(65) 


X 


X 


X 


© 



X 


X 




© 


X 


X 




(69) 






X 


© 






X 


© 






X 


© 




X 




(73) 



© Indicate shape as flat, dished, ellipsoidal, torispherical, or hemispherical. 

© Use inside dimensions for size. 

© Indicate shape as square, round, etc. 

© Outside diameter. 

© Minimum thickness of tubes. 

© Size. 

© Describe type as flanged, welding neck, etc. 

© Show name of part (e.g., steam drum, waterwall header). 

© Show data line number on applicable form for the named part. 

© Any additional information to clarify the report should be entered here. 

© List each individual section that makes up boiler assembly. Show 
pattern and/or part number for each section. Show drawing number 
for each section. Show metal thickness for each section as indicated 
on the drawings. List each section of the complete boiler. 

© Show bursting pressure of each section of boiler. Show thickness 
measured at the break or fracture of each section. Indicate weight of 
each section. 

© Indicate minimum specified tensile strength for the class of iron as set 
forth in Table HC-300. 

® Indicate sections of boiler that represent specimen test bars. Show 
results of each specimen tested (tensile strength). 

© Show maximum allowable working pressure as determined by Formula 
HC-402 and by values allowed by Formula HC-402. 

© The individual designated to conduct tests, the designated 

manufacturer's representative who witnesses test and date or dates 

on which destruction tests were conducted. 

Designated responsible engineering head certifying the tests and date. 

Show quantity and dimensions. 

Type of lining, if applicable. 

Maximum allowable working pressure established in accordance with 

HLW-300 or HLW-500 of Section IV. 
© Indicate maximum allowable input, For tanks used for 

storage, indicate "storage only." 

Maximum temperature in accordance with HLW-300 of Section IV. 

Hydrostatic pressure applied in accordance with HLW-505 of Section 

IV and witnessed by the Authorized Inspector. 

Part of vessel yielding first should be indicated. 

Pressure at which yielding occurs as evidenced by flaking of the brittle 

coating or by appearance of strain lines. 

Show yield strength for each of the three specimens and average of 

the three. 

This ID number is a unique identifying number for this form, which 

may be assigned by the Certificate Holder if desired. 
@ Maximum water temperature. 
© Fill in information identical to that shown on the Data Report Form to 

which this sheet is supplementary. 



202 



2007 SECTION IV 



FORM H-2 MANUFACTURER'S DATA REPORT FOR ALL TYPES OF BOILERS 

EXCEPT WATERTUBE AND THOSE MADE OF CAST IRON 

As Required by the Provisions of the ASME Code Rules, Section IV 



1. Manufactured and certified by 

2. Manufactured for 



© 



(name and address of manufacturer) 
© 



3. Location of installation 

4. Unit identification 



(name and address of purchaser) 
© 



(name and address) 



© 



© 



© 



(complete boiler, superheater, (manufacturer's serial no.) 
waterwall, economizer, etc.) 



(drawing no.) (National Bd. no.) 



(year built) 



5. The chemical and physical properties of all parts meet the requirements of material specifications of the ASME BOILER AND PRESSURE 

VESSEL CODE. The design, construction, and workmanship conform to ASME Code, Section IV, © ® ® 

(year) [addenda (date)] (Code Case no.) 

Manufacturer's Partial Data Reports properly identified and signed by Commissioned Inspectors have been furnished for the following items of 
this report © ® 



6. Shells or drums — ® 

7. Joints 



(name of part, item number, manufacturer's name, and identifying stamp) 
© © © 



(no.) (material spec, gr.) 
© 



(thickness) 
© 



[long, (seamless, welded)] 



8. Tubesheet 

9. Tubes: No. 

10. Heads — 

11. Furnace 



© 



(material spec, grade) (thickness) 



[eff. (compared to seamless)] 

. Tube holes 



(inside diameter) [length (overall)] (inside diameter) [length (overall)] 
© 



[girth (seamless, welded)] 



(no. of shell courses) 



(number and diameter) 



© 



(material spec, grade) (straight or bent) 
© 



Diameter 



Length 



(material spec no.) 
© © 



(thickness) 



(if various, give max. and min.) 

(flat, dished, ellipsoidal) 
© ©. 



.Gauge 



(radius of dish) 



(material spec, gr.) (thickness) (no.) [size (O.D. or W x H)] [length (each section)] (total) [type (plain, corrugated, etc.)] 



Seams 



12. Staybolts 



© 



© 



© 



[type (seamless, welded)] 
© 



(no.) [size (diameter)] (material spec, gr.) (size) (telltale) 



(net area) [pitch (horizontal and vertical)] (MAWP) 



13. Stays or braces: 



Location 


Material 
Spec. 


Type 


Number 
and Size 


Pitch 


Total 
Net Area 


Fig. HG-343 
L/l 


Dist. Tubes 
to Shell 


MAWP 


(a) F.H. above tubes 


© 


@ 






@ 


© 






(b) R.H. above tubes 


















(c) F.H. below tubes 


















(d) R.H. below tubes 


















(e) Through stays 



















14. Other parts: 1. 

1. 

2. 



(brief description, i.e., dome, boiler piping) 
@ © 



(material spec, grade, size, material thickness, MAWP) 



15. Nozzles, inspection, and safety valve openings: 



Purpose 
(inlet, outlet, drain, etc.) 


No. 


Diameter 
or Size 


Type 


How 
Attached 


Material 


Nominal 
Thickness 


Reinforcement 
Material 


Location 


Handhole 










NA 




NA 




Manhole 




























© 































































(09/06) 



203 



2007 SECTION IV 



FORM H-2 (Back) 



16. Boiler supports 



(no.) Itype (saddles, legs, lugs)] [attachment (bolted or welded)] 

® Based on @ Heatina surface ® 



17. MAWP ^ Based on ^ Heating surface )& Shop hydro, test 

18. Maximum water temperature . 

19. Remarks 



(Code par. and/or formula) (total) (complete boiler) 

(74) 



CERTIFICATE OF SHOP COMPLIANCE 

We certify that the statements made in this data report are correct and that all details of design, material, construction, and workmanship of 
this boiler conform to Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. 

"H" Certificate of Authorization no. ^2 expires , 

Date © Signed Name 



(by representative) (manufacturer that constructed and certified boiler) 



© CERTIFICATE OF SHOP INSPECTION 

Boiler constructed by at 



I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of Si and employed by 

have inspected parts of this boiler referred to as data items S2 and 



have examined Manufacturers' Partial Data Reports for items ±=2. 

and state that, to the best of my knowledge and belief, the manufacturer has constructed this boiler in accordance with the applicable sections 
of the ASME BOILER AND PRESSURE VESSEL CODE. 

By signing this certificate neither the Inspector nor his employer makes any warranty, expressed or implied, concerning the boiler described in 
this Manufacturer's Data Report. Furthermore, neither the Inspector nor his employer shall be liable in any manner for any personal injury or 
property damage or a loss of any kind arising from or connected with this inspection. 



Date Signed Commissions 



© 



(Authorized Inspector) [National Bd. (incl. endorsements), state, prov., and no.] 



CERTIFICATE OF FIELD ASSEMBLY COMPLIANCE 

We certify that the field assembly construction of all parts of this boiler conforms with the requirements of Section IV of the ASME BOILER 
AND PRESSURE VESSEL CODE. 

"H" Certificate of Authorization no. s: expires , 

Date ® Signed Name 



(by representative) (assembler that certified and constructed field assembly) 



© CERTIFICATE OF FIELD ASSEMBLY INSPECTION 

I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of S: and employed by 

have compared the statements in this Manufacturer's Data Report with the described boiler and state that 

the parts referred to as data items S2 , not included in the certificate of shop inspection, have 

been inspected by me and that to the best of my knowledge and belief the manufacturer and/or the assembler has constructed and assembled 
this boiler in accordance with the applicable sections of the ASME BOILER AND PRESSURE VESSEL CODE. The described boiler was inspected 
and subjected to a hydrostatic test of @ 

By signing this certificate neither the Inspector nor his employer makes any warranty, expressed or implied, concerning the boiler described in 

this Manufacturer's Data Report. Furthermore, neither the Inspector nor his employer shall be liable in any manner for any personal injury or 

property damage or a loss of any kind arising from or connected with this inspection. 

Date Signed Commissions §2 

(Authorized Inspector) [National Bd. (incl. endorsements) state, prov., and no.] 

(09/06) 



204 



2007 SECTION IV 



FORM H-3 MANUFACTURER'S DATA REPORT FOR WATERTUBE BOILERS 
As Required by the Provisions of the ASME Code Rules, Section IV 



1. Manufactured and certified by 

2. Manufactured for 







(name and address of manufacturer) 
© 



3. Location of installation 

4. Unit identification 



(name and address of purchaser) 
© 



(name and address) 



© 



© 



(complete boiler, superheater, waterwall, etc.) (manufacturer's serial no.) 



(drawing no.) 



© 



(National Bd. no.) 



(year built) 



5. The chemical and physical properties of all parts meet the requirements of material specifications of the ASME BOILER AND PRESSURE 

VESSEL CODE. The design, construction, and workmanship conform to ASME Code, Section IV, © ® ® 

(year) [addenda (date)] (Code Case no.) 

6. (a) Drums: 



No. 


Inside 
Diameter 


Inside Length 


Shell Plates 


Tube Sheets 


Tube Hole Ligament 
Efficiency, % 


Material Spec. Grade 


Thickness 


Inside Radius 


Thickness 


Inside Radius 


Longitu- 
dinal 


Circum- 
ferential 


1 






© 


© 




© 








2 





















No. 


Longitudinal 
Joints 


Circum. 
Joints 


Heads 


Hydro- 
static 
Test 


No. & 
Type* 


Effi- 
ciency 


No. & 
Type 


Effi- 
ciency 


Material Spec. Grade 


Thickness 


Type** 


Radius 
of Dish 


1 










© 


® 






© 


© 


2 























'Indicate if (1) seamless, (2) fusion welded. 
6. (b) Boiler tubes: 



Diameter 


Thickness 


Material 
Spec. No. Grade 


No. 


How 
Attached • 





















































"Indicate if (1) flat, (2) dished, (3) ellipsoidal, (4) hemispherical. 

6. (c) Headers no © © © or © 

(box or sinuous or round, material spec, no., thickness) 

Heads or ends © © © Hydro, test © 

(shape, material spec, no., 
thickness) 

6. (d)Staybolts © 



Pitch 



(material spec, no., diameter, size telltale, net area) 

Net area 



6. (e) Mud drum © © © ©or© Heads or ends © © © 



(for sect, header boilers state size, 
shape, material spec, no., thickness) 



(shape, material spec, no., 
thickness) 



(supported 
by one bolt) 

. Hydro, test 



Design pressure . 

© 



7. Waterwall headers: 



No. 


Size and Shape 


Material 
Spec. No. Gr. 


Thickness 


Shape 


Thickness 


Material 
Spec. No. Gr. 


Hydro. 
Test 


Diameter 


Thickness 


Material 
Spec. No. Gr. 


1 


© © 


© 


@or@ 


© 


© 


© 


© 


© 


© 


© 


2 






















3 























8. (a) Other parts (1). 



.(2). 



.(3). 



(b) Tubes for other parts 



1 






















2 






















3 























9. Nozzles, inspection, and safety valve openings: @ 



Purpose 
(inlet, outlet, drain, etc.) 


No. 


Diameter 
or Size 


Type 


How 
Attached 


Material 


Nom. 
Thickness 


Reinforcement 
Material 


Location 


Handhole 




© 


© 




NA 




NA 




Manhole 




























© 

















































































(09/06) 



205 



2007 SECTION IV 



FORM H-3 (Back) 



10. 




MAWP 


Maximum 
water temp. 


Shop Hydro. Test 


Heating 
Surface 


a 


Boiler 


© 


® 






b 


Waterwall 










c 


Superheater 










d 


Other parts 











f Heating surface 
J to be stamped 
I /] on drum heads. 
Y f This heating 
J surface not to 
1 J be used for 
L/| determining 
| minimum safety 
J I valve capacity. 



11. Field Hydro. Test 



12. Manufacturer's Partial Data Reports properly identified and signed by Commissioned Inspectors have been furnished for the following items 

of this report @ © 

(name of part, item number, manufacturer's name, and identifying stamp) 



13. Remarks 



CERTIFICATE OF SHOP COMPLIANCE 

We certify that the statements made in this data report are correct and that all details of design, material, construction, and workmanship of this 
boiler conform to Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. 

"H" Certificate of Authorization No. sH expires , 

Date ® Signed Name 



(by representative) 



(manufacturer that constructed and certified boiler) 



© 



CERTIFICATE OF SHOP INSPECTION 

at 



Boiler constructed by 

I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of © 



and employed by. 



have inspected parts of this boiler referred to as data items 



and 



© 



have examined Manufacturer's Partial Data Reports for items 

and state that, to the best of my knowledge and belief, the manufacturer has constructed this boiler in accordance with Section IV of the ASME 

BOILER AND PRESSURE VESSEL CODE. 

By signing this certificate neither the inspector nor his employer makes any warranty, expressed or implied, concerning the boiler described 

in this Manufacturer's Data Report. Furthermore, neither the inspector nor his employer shall be liable in any manner for any personal injury 

or property damage or a loss of any kind arising from or connected with this inspection. 

Date Signed Commissions ^ 



(Authorized Inspector) 



[National Bd. (incl. endorsements), state, prov., and no.) 



CERTIFICATE OF FIELD ASSEMBLY COMPLIANCE 

We certify that the field assembly construction of all parts of this boiler conforms with the requirements of Section IV of the ASME BOILER 
AND PRESSURE VESSEL CODE. 

"H" Certificate of Authorization no. ® expires , 

Date ® Signed Name 



(by representative) 



(assembler that certified and constructed field assembly) 



@ CERTIFICATE OF FIELD ASSEMBLY INSPECTION 

I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of <z and employed by 

have compared the statements in this Manufacturer's Data Report with the described boiler and state that 

the parts referred to as data items @ not included in the certificate of shop inspection, have been inspected by me 

and that to the best of my knowledge and belief the manufacturer and/or the assembler has constructed and assembled this boiler in accordance 
with Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. The described boiler was inspected and subjected to a hydrostatic test 

of 

By signing this certificate neither the inspector nor his employer makes any warranty, expressed or implied, concerning the boiler described 
in this Manufacturer's Data Report. Furthermore, neither the inspector nor his employer shall be liable in any manner for any personal injury 
or property damage or a loss of any kind arising from or connected with this inspection. 
Date Signed Commissions §2 



(Authorized Inspector) 



[National Bd. (incl. endorsements), state, prov., and no.) 



(09/06) 



206 



2007 SECTION IV 



FORM H-4 MANUFACTURER'S PARTIAL DATA REPORT 

As Required by the Provisions of the ASME Code Rules 

(Attach to the Applicable Data Report, Section IV) 



1. Manufactured and certified by 

2. Manufactured for 



© 



H-4 ID# © 



(name and address of manufacturer) 



© 



(name and address of purchaser) 



3. Location of installation 

4. Identification of part(s): 



© 



(name and address) 



Name of Part 


Line 
No. 


Manufacturer's 
Serial No. 


Manufacturer's 
Drawing No. 


CRN 


National Bd. No. 


Year 
Built 


® 


© 


© 








© 









































































5. The chemical and physical properties of all parts meet the requirements of material specifications of the ASME BOILER AND PRESSURE 

VESSEL CODE. The design, construction, and workmanship conform to ASME Code, Section IV, © ® ® 

(Year) [addenda (date)J (Code Case no.) 

6. (a) Drums: 



No. 


Inside 
Diameter 


Inside Length 


Shell Plates 


Tube Sheets 


Tube Hole Ligament 
Efficiency, % 


Material Spec. No. Grade 


Thickness 


Inside Radius 


Thickness 


Inside Radius 


Longitu- 
dinal 


Circum- 
ferential 


1 






© 


© 




© 








2 





















No. 


Longitudinal 
Joints 


Circum. 
Joints 


Heads 


Hydro- 
static 
Test 


No. & 
Type* 


Effi- 
ciency 


No. & 
Type 


Effi- 
ciency 


Material Spec. No. Grade 


Thickness 


Type** 


Radius 
of Dish 


1 










© 


© 






@ 


© 


2 























'Indicate if (1) seamless, (2) fusion welded. 
6. (b) Boiler tubes: 



6. (c) Headers no 



♦♦Indicate if (1) flat, (2) dished, (3) ellipsoidal, (4) hemispherical. 
@ © @or@ 



Diameter 


Thickness 


Material 
Spec. No. Grade 


No. 


How 
Attached 





















































(box or sinuous or round, material spec, no., thickness) 

Heads or ends © © © Hydro, test ©_ 



(shape, material spec, no., 
thickness) 



6. (d)Staybolts 
Pitch 



© 



(material spec. no. diameter, size telltale; r.et area) 



Net area 



6. (e) Mud drum © © © ©or© Heads or ends © © © 

(f 

sh 

7. Waterwall headers: 



(for sect, header boilers, state size, 
shape, material spec, no., thickness) 



(shape, material spec, no., 
thickness) 



(supported 
by one bolt) 



. Hydro, test. 



Design pressure . 

© 



No. 


Size and Shape 


Material 
Spec. No. Gr. 


Thickness 


Shape 


Thickness 


Material 
Spec. No. Gr. 


Hydro 
Test 


Diameter 


Thickness 


Material 
Spec. No. Gr. 


1 


© 


© 


©or («) 


© 


© 


© 


© 


© 


© 


© 


2 






















3 























8. (a) Other parts (1). 



.(2). 



.(3). 



(b) Tubes for other parts 



2 
3 



(09/06) 



207 



2007 SECTION IV 



FORM H-4 (Back) 



9. Nozzles, inspection and safety valve openings: 



Purpose 
(inlet, outlet, drain, etc.) 


No. 


Diameter 
or Size 


Type 


How 
Attached 


Material 


Nom. 
Thickness 


Reinforcement 
Material 


Location 


Handhole 




© 


© 




NA 




NA 































































































10. 




MAWP 


Maximum 
Water Temp. 


Shop Hydro. Test 


Heating 
Surface 


3 


Boiler 


© 


© 






b 


Waterwall 










c 


Other parts 











f Heating surface or 
-< kW to be stamped 
|_ on drum heads 
( This heating surface 
J not to be used for 
| determining minimum 
l safety valve capacity. 



11. Field Hydro. Test 



12. Remarks 



CERTIFICATE OF SHOP COMPLIANCE 

We certify that the statements made in this partial data report are correct and that all details of design, material, construction, and workmanship 
of these parts conform to Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. 
"H" Certificate of Authorization no. sL 

© 



expires 



Date. 



. Signed. 



Name 



(by representative) 



(manufacturer that constructed and certified boiler) 



(33) CERTIFICATE OF SHOP INSPECTION 

I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of Si and employed by 

have inspected the part of a boiler described in this Manufacturer's Partial 

Data Report on , , and state that to the best of my knowledge and belief, the manufacturer has 

constructed this part in accordance with Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. By signing this certificate neither the 
Inspector nor his employer makes any warranty, expressed or implied, concerning the part described in this Manufacturer's Partial Data Report. 
Furthermore, neither the Inspector nor his employer shall be liable in any manner for any personal injury or property damage or a loss of any 
kind arising from or connected with this inspection. 



Date. 



Signed. 



Commissions 



© 



(Authorized Inspector) 



[National Bd. (incl. endorsements), state, prov., and no.] 



(09/06) 



208 



2007 SECTION IV 



FORM H-5 MANUFACTURER'S MASTER DATA REPORT FOR BOILERS 

CONSTRUCTED FROM CAST IRON 

As Required by the Provisions of the ASME Code Rules, Section IV 



1. Manufactured and certified by _ 



© 



(name and address of manufacturer) (foundry identification) 



2. Boiler type or model no. 

3. Boiler section data: © 



© 



Section Designation 

(list each individual section 

in boiler assembly) 



Pattern and/or 
Part No. 



Metal Thickness 
According to Drawing 



(a), 
(b). 
(0. 
(d). 
(e). 



4. Boiler section bursting data: @ 



Bursting Pressure, Metal Thickness Measured at Break or 
Fracture, and Weight of Section 



Section Designation 



Test No. 1 



Test No. 2 



Test No. 3 



(a). 



(b). 



(c) 



(d). 



(e). 



5. Minimum specified tensile strength 



© 



6. Tensile strength of associated test bars: (go) 
Section Designation 



Bar for 
Test No. 1 



Bar for 
Test No. 2 



Bar for 
Test No. 3 



(a), 
(b). 
(0. 
(d). 
(e). 



7. Specification no. and class of gray iron 



8. Maximum Allowable working pressure of boiler* 



© 



•Determined by using formula in HC-402 and by selection of lowest values of bursting pressure from tests recorded in item 4 of this report. 



(09/06) 



209 



9. Sketch of section with lowest bursting pressure: 

Show location of 

failure and indicate whether 

principally in bending or tension. 



10. Examination data: (g) 

(a) Test engineer. 



(b) Witness of test(s) 



(c) Date(s) of destruction tests 



11. Manufacturer's certification: (5) 
Date 



2007 SECTION IV 



FORMH-5 (Back) 



Certified to be true record 



(name and title) 
NOTE: Signature of designed responsible engineering head of the manufacturer must be notarized. 

12. ASME Certificate of Authorization no. © 

Certificate expires , 



to use the "H" symbol (cast iron). 



(09/06) 



210 



2007 SECTION IV 



FORM H-5A MANUFACTURER'S MASTER DATA REPORT FOR BOILERS 

CONSTRUCTED FROM CAST ALUMINUM 

As Required by the Provisions of the ASME Boiler and Pressure Vessel Code Rules, Section IV 



1. Manufactured and certified by _ 



© 



07 



(name and address of manufacturer) (foundry identification) 



2. Boiler type or model no. 

3. Boiler section data: @ 



Section Designation 

(List Each Individual Section 

in Boiler Assembly) 



© 



Pattern and/or 
Part No. 



Metal Thickness 
According to Drawing 



(a), 
(b). 
(0. 
(d). 
(e). 



4. Boiler section bursting data: @ 



Section Designation 



Bursting Pressure, Metal Thickness Measured at Break or 
Fracture, and Weight of Section 



Test No. 1 



Test No. 2 



Test No. 3 



(a). 



(b). 



(c). 



(d). 



(e). 



5. Minimum specified tensile strength 



6. Tensile strength of associated test bars: @ 
Section Designation 



<§> 



Bar for 
Test No. 1 



Bar for 
Test No. 2 



Bar for 
Test No. 3 



(a), 
(b). 
(0. 
<d). 
(e). 



7. Specification no. of aluminum alloy 



8. Maximum allowable working pressure of boiler 1 



© 



1 Determined by using formula in HA-402 and by selection of lowest values of bursting pressure from tests recorded in item 4 of this report. 
(02/07) 



211 



2007 SECTION IV 

FORMH-5A (Back) 

9. Sketch of section with lowest bursting pressure (show location of failure) 



10. Examination data: @ 

(a) Test engineer . 



(b) Witness of test(s) 



(c) Date(s) of destruction tests 



11. Manufacturer's certification: (g) 
Date 



Certified to be true record 



(name and title) 

NOTE: Signature of designed responsible engineering head of the manufacturer must be notarized. 

12. ASME Certificate of Authorization no. © to use the "H" symbol (cast aluminum). 

Certificate expires , 



(02/07) 



212 



2007 SECTION IV 



FORM H-6 MANUFACTURER'S DATA REPORT SUPPLEMENTARY SHEET 
As Required by the Provisions of the ASME Boiler and Pressure Vessel Code Rules, Section IV 



1. Manufactured and certified by 

2. Manufactured for 



3. Location of installation 

4. Unit identification 

©@ 



©@ 



©@ 



0© 



(name and address of manufacturer) 
©@ 



(name and address of purchaser) 



(name and address) 



®@ 



(manufacturer's serial no.) 



®@ 



®@ 



(drawing no.) 



(National Board no.) 



(year built) 



Data Report 
Item Number 



Remarks 



Certificate of Authorization: Type _ 
Date ® Name . 



No. 



© 



(manufacturer) 



Date . 
(11/06) 



Name 



(authorized inspector) 



Signed 



Commissions 



Expires 



(representative) 
© 



[National Board (incl. endorsements), state, province, and no.] 



213 



2007 SECTION IV 



FORM HC-1 MANUFACTURER'S MATERIAL CERTIFICATE OF CONFORMANCE 
FOR CAST IRON BOILER SECTIONS 



1. Manufactured and certified by 

2. List of cast iron sections: 



(name and address of manufacturer) (foundry designation) 



Pattern # 


Cast Date 


Quantity 


Date of Last Burst Test 



































































































































































































































































3. The chemical and physical properties of sections listed here meet the material requirements of Part HC, Article 2. 

4. Date Signed 

5. Date Signed 



(by representative) 



6. ASME Certificate of Authorization No. 



(by certified individual) 

_ to use the "H" symbol (cast iron). Certificate expires 



(11/06) 



214 



2007 SECTION IV 



FORM HC-2 MANUFACTURER'S MATERIAL CERTIFICATE OF CONFORMANCE 
FOR HYDROSTATIC TESTING OF CAST IRON BOILER SECTIONS 



1. Manufactured and certified by 

2. List of cast iron sections: 



(name and address of manufacturer) (foundry designation) 



Pattern # 


Quantity 


MAWP 


Hydrostatic Test Pressure 



































































































































































































































































3. Sections listed here have satisfactorily passed the hydrostatic test required in HC-410. 

4. Date Signed 

5. Date Signed 



(by representative) 



6. ASME Certificate of Authorization No. 



(by certified individual) 

to use the "H" symbol (cast iron). Certificate expires 



(11/06) 



215 



2007 SECTION IV 



07 



FORM HA-1 MANUFACTURER'S MATERIAL CERTIFICATE OF CONFORMANCE 
FOR CAST ALUMINUM BOILER SECTIONS 



1. Manufactured and certified by . 

2. List of cast aluminum sections 



(name and address of manufacturer) (foundry designation) 



Pattern # 


Cast Date 


Quantity 


Date of Last Burst Test 



































































































































































































































































3. The chemical and physical properties of sections listed here meet the material requirements of Part HA, Article 2 and Part HF. 

4. Date Signed 

5. Date Signed 



(by representative) 



6. ASME Certificate of Authorization No. 



(by certified individual) 

_ to use the "H" symbol (cast aluminum). Certificate expires 



(01/07) 



216 



2007 SECTION IV 



FORM HA-2 MANUFACTURER'S MATERIAL CERTIFICATE OF CONFORMANCE 
FOR HYSTROSTATIC TESTING OF CAST ALUMINUM BOILER SECTIONS 



07 



1. Manufactured and certified by . 

2. List of cast aluminum sections 



(name and address of manufacturer) (foundry designation) 



Pattern # 


Quantity 


MAWP 


Hydrostatic Test Pressure 



































































































































































































































































3. Sections listed here have satisfactorily passed the hydrostatic test required in HA-406. 

4. Date Signed 

5. Date Signed 



(by representative) 



6. ASME Certificate of Authorization No. 



(by certified individual) 

_ to use the "H" symbol (cast aluminum). Certificate expires 



(02/07) 



217 



2007 SECTION IV 



FORM HLW-6 MANUFACTURER'S DATA REPORT FOR WATER HEATERS OR STORAGE TANKS 
As Required by the Provisions of the ASME Code Rules 



1. Manufactured and certified by 

2. Manufactured for 



©. 



(name and address of manufacturer) 
© 



3. Location of installation 



4. Identification 



(name and address of purchaser) 
© 



(name and address) 



© 



© 



(manufacturer's serial no.) (CRN) (drawing no.) (National Board no.) (year built) 

5. The chemical and physical properties of all parts meet the requirements of material specifications of the ASME BOILER AND PRESSURE 
VESSEL CODE. The design, construction, and workmanship conform to Part HLW, Section IV © ® © 



fi 


Shell 
Joints 

Heads . 


® 

(no.) 


© 


7 


(material spec, gr.) 
© 


8. 




[long, (seamless, welded)] 
© 



© 



(year) 
© 



[addenda (date)] (Code Case no.) 



thickness 
© 



(lining) 



© 



[length (overall)] 



[eff. (compared to seamless)] 



[girth (seamless, welded)] 



(no. of shell courses) 



Location 


Material Spec, 
Gr, Thickness 


Crown Radius 


Knuckle Radius 


Elliptical Ratio 


Flat Diameter 


Side Pressure 
(concave, convex) 































9. Tubesheet 



© 



Tubes 



© 



(material spec, gr.) (no.) (size) 

10. Nozzles, inspection, and safety valve openings: @ 



[length (overall)] 



(material spec, gr.) 



(rolled or welded) 



Purpose 
(inlet, outlet, drain, etc.) 


No. 


Diameter 
or Size 


Type 


How 
Attached 


Material 


Nominal 
Thickness 


Reinforcement 
Material 


Location 


Handhole 






NA 




NA 




NA 


















































© 

















































































11. MAWP. 



© 



Max. input 



© 



Max. temp. 



© 



Hydrostatic test 



© 



12. Manufacturer's Partial Data Reports properly identified and signed by Commissioned Inspectors have been furnished for the following items of 
this report © @ 

(name of part, item no., manufacturer's name, identification stamps) 



13. Remarks 



(09/06) 



218 



2007 SECTION IV 



FORM HLW-6 (Back) 



CERTIFICATE OF SHOP COMPLIANCE 

We certify that the statements made in this data report are correct and that all details of design, material, construction, and workmanship of 
this water heater or storage tank conform to Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. 
"HLW" Certificate of Authorization no. expiration date 



Date Name Signed 



(manufacturer that constructed and certified water heater or storage tank) (by representative) 



CERTIFICATE OF SHOP INSPECTION 



Constructed by at 

I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of and employed by 

have inspected parts referred to as data items 

and have examined Manufacturer's Partial Data Reports for items 



and state that, to the best of my knowledge and belief, the manufacturer has constructed this water heater or storage tank in accordance with 
Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. 

By signing this certificate, neither the Inspector nor his employer makes any warranty, expressed or implied, concerning the water heater or 
storage tank described in this Manufacturer's Data Report. Furthermore, neither the Inspector nor his employer shall be liable in any manner for 
any personal injury or property damage or a loss of any kind arising from or connected with this inspection. 

Date Signed Commissions 



(Authorized Inspector) [National Bd. (incl. endorsements), state, province, and no.l 



(09/06) 



219 



2007 SECTION IV 



FORM HLW-7 MANUFACTURER'S PARTIAL DATA REPORT FOR WATER HEATERS AND STORAGE TANKS 
As Required by the Provisions of the ASME Code Rules (Attach to the Applicable Form HLW-6 Data Report) 



1. Manufactured and certified by 

2. Manufactured for 



3. Identification of part(s): 



© 



HLW-7 ID# 



© 



(name and address of manufacturer) 
©_ 



(name and address of purchaser) 



Name of Part 


Line No. 


Identifying No. 


Manufacturer's Drawing No. 


Year Built 


© 


© 


© 




© 

































4. The chemical and physical properties of all parts meet the requirements of material specifications of the ASME BOILER AND PRESSURE VESSEL 

CODE. The design, construction, and workmanship conform to Part HLW, Section IV © and Addenda to ® 

(year) (date) 

5. Shell ® © © © © 



6. Joints . 



(material spec, gr.) 
© 



(thickness) 
© 



(lining) 



llength (overall)] 



7. Heads. 



[long, (seamless, welded)] 
© 



[eff. (compared to seamless)] 



© 



[girth (seamless, welded)] 



(no. of shell courses) 



Location 


Material Spec, 
Gr., Thickness 


Crown Radius 


Knuckle Radius 


Elliptical Ratio 


Flat Diameter 


Side Pressure 
(concave, convex) 













































8. Tubesheet 

9. Tubes 



© 



(material spec, gr.) 

Size Length 



Tube holes 



Material spec, gr. 



(no. and diameter) 

Ql Thickness 



10. Connections: 



Purpose 


No. 


Size or Diameter 


Material Spec, Gr. 


Thickness 


Reinforcement 
Material 







































11. MAWP 



© 



Max. input 



© 



Max. temp. 



© 



Hydrostatic test 



12. Remarks 



(09/06) 



220 



2007 SECTION IV 



FORM HLW-7 (Back) 



CERTIFICATE OF SHOP COMPLIANCE 

We certify the statements in this Manufacturer's Partial Data Report to be correct and that all details of material, construction, and workmanship 
of this water heater or storage tank conform to Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. 

Certificate of Authorization no. Si to use the "HLW" symbol expires . 



Date ® Signed by 



(manufacturer that constructed and certified parts) (authorized representative) 



@ CERTIFICATE OF SHOP INSPECTION 

I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of and employed by 

have inspected the part described in this Manufacturer's Partial Data Report on 

and state that, to the best of my knowledge and belief, the manufacturer has constructed this part in accordance with Section IV of the ASME 
BOILER AND PRESSURE VESSEL CODE. 



By signing this certificate, neither the inspector nor his employer makes any warranty, expressed or implied, concerning the part described in this 
Manufacturer's Partial Data Report. Furthermore, neither the inspector nor his employer shall be liable in any manner for any personal injury or property 
damage or a loss of any kind arising from or connected with this inspection. 



Date Signed Commissions 



© 



(Authorized Inspector) [National Bd. (incl. endorsements), state, province, and no.] 



(09/06) 



221 



2007 SECTION IV 



FORM HLW-8 MANUFACTURER'S MASTER DATA PROOF TEST REPORT 

FOR WATER HEATERS OR STORAGE TANKS 

As Required by the Provisions of the ASME Code Rules, Section IV 



1. Manufactured and certified by 



© 



2. Vessel type or model no. (HLW-500) 

3. Vessel proof test data: 



(name and address) 
® 



Vessel Parts 


Description 
or Part No. 


Material Spec, Gr., Thickness 
According to Drawing 


Specified Yield 
Strength 


Minimum 
Tensile 


( a ) 




© ® 






( h ) 










('•) 










( H ) 










( p ) 





















4. Type of coating 



(lime wash or other brittle coating) 



5. Test data to determine yielding: 



Part Designation 
Yielding 


Yielding Pressure by 

Flaking of Coating or 

by Strain Lines 


Location of Yielding 

Whether Bending or Tension 

(indicate on sketch) 


© 


© 


© 

































6. Yield strength of test specimens [HLW-502.1(c)]: (a) 

7. Maximum allowable working pressure of vessel 

8. Examination data: @ 

(a) Test engineer 



© 



(b). 



(0 



® 



Average 



[determined by formulas in HLW-502.1(d)] 



(b) Witness of test 

(c) Date(s) of proof test 



MANUFACTURER'S CERTIFICATION 

We certify that the above data is correct and that the proof test procedure conforms with HLW-500 of Section IV of the ASME BOILER AND 

PRESSURE VESSEL CODE. 

ASME Certificate of Authorization no. _ 



© 



to use the "HLW" symbol expiration date 



Date 



© 



. Certified to be true record 



(authorized representative)* 
*NOTE: Signature of manufacturer's designated responsible engineering representative is required. 



(manufacturer) 



© PROOF TEST CERTIFICATE 

I, the undersigned, holding a valid commission issued by the National Board of Boiler and Pressure Vessel Inspectors and/or the state or province 

of SZ and employed by 

have witnessed the proof test and the procedures conforming to HLW-500 of Section IV of the ASME BOILER AND PRESSURE VESSEL CODE. 

By signing this certificate, neither the Inspector nor his employer makes any warranty, expressed or implied, concerning the water heater or 
storage tank described in this Manufacturer's Proof Test Report. Furthermore, neither the Inspector nor his employer shall be liable in any manner 
for any personal injury or property damage or a loss of any kind arising from or connected with the witnessing of this proof test. 



Date 



(09/06) 



Signed 



Commissions 



© 



(Authorized Inspector) 



(state, province, and no.) 



222 



2007 SECTION IV 



NONMANDATORY APPENDIX M 

GUIDANCE FOR THE USE OF U.S. CUSTOMARY AND 

SI UNITS IN THE ASME BOILER AND PRESSURE 

VESSEL CODE 



M-l 



USE OF UNITS IN EQUATIONS 



The equations in this Nonmandatory Appendix are suit- 
able for use with either the U.S. Customary or the SI 
units provided in Mandatory Appendix 6, or with the units 
provided in the nomenclature associated with that equation. 
It is the responsibility of the individual and organization 
performing the calculations to ensure that appropriate units 
are used. Either U.S. Customary or SI units may be used 
as a consistent set. When necessary to convert from one 
system of units to another, the units shall be converted to 
at least three significant figures for use in calculations and 
other aspects of construction. 



M-2 GUIDELINES USED TO DEVELOP 

SI EQUIVALENTS 

The following guidelines were used to develop SI equiv- 
alents: 

(a) SI units are placed in parentheses after the U.S. 
Customary units in the text. 

(b) In general, separate SI tables are provided if interpo- 
lation is expected. The table designation (e.g., table num- 
ber) is the same for both the U.S. Customary and SI tables, 
with the addition of suffix "M" to the designator for the 
SI table, if a separate table is provided. In the text, refer- 
ences to a table use only the primary table number (i.e., 
without the "M"). For some small tables, where interpola- 
tion is not required, SI units are placed in parentheses after 
the U.S. Customary unit. 

(c) Separate SI versions of graphical information 
(charts) are provided, except that if both axes are dimen- 
sionless, a single figure (chart) is used. 

(d) In most cases, conversions of units in the text were 
done using hard SI conversion practices, with some soft 
conversions on a case-by-case basis, as appropriate. This 
was implemented by rounding the SI values to the number 
of significant figures of implied precision in the existing 



U.S. Customary units. For example, 3,000 psi has an 
implied precision of one significant figure. Therefore, the 
conversion to SI units would typically be to 20 000 kPa. 
This is a difference of about 3% from the "exact" or soft 
conversion of 20 684.27 kPa. However, the precision of 
the conversion was determined by the Committee on a 
case-by-case basis. More significant digits were included 
in the SI equivalent if there was any question. The values 
of allowable stress in Section II, Part D generally include 
three significant figures. 

(e) Minimum thickness and radius values that are 
expressed in fractions of an inch were generally converted 
according to the following table: 





Proposed 




Fraction, in. 


SI Conversion, mm 


Difference, % 


62 


0.8 


-0.8 


3/ 
'(A 


1.2 


-0.8 


y i6 


1.5 


5.5 


3/ 
'32 


2.5 


-5.0 


X 


3 


5.5 


5 / 


4 


-0.8 


X 


5 


-5.0 


\ 


5.5 


1.0 


X 


6 


5.5 


X 


8 


-0.8 


% 


10 


-5.0 


X 


11 


1.0 


X 


13 


-2.4 


X 


14 


2.0 


% 


16 


-0.8 


% 


17 


2.6 


X 


19 


0.3 


X 


22 


1.0 


1 


25 


1.6 



(f) For nominal sizes that are in even increments of 
inches, even multiples of 25 mm were generally used. 
Intermediate values were interpolated rather than con- 
verting and rounding to the nearest mm. See examples in 
the following table. [Note that this table does not apply to 
nominal pipe sizes (NPS), which are covered below.] 



223 



2007 SECTION IV 



Size, in. 



Size, mm 



1 


25 


156 


29 


\\ 


32 


\\ 


38 


2 


50 


2\ 


57 


2 l / 2 


64 


3 


75 


3fc 


89 


4 


100 


4* 


114 


5 


125 


6 


150 


8 


200 


12 


300 


18 


450 


20 


500 


24 


600 


36 


900 


40 


1000 


54 


1350 


60 


1500 


72 


1800 


Size or Length, 




ft 


Size or Length, m 


3 


1 


5 


1.5 


200 


60 



(g) For nominal pipe sizes, the following relationships 
were used: 



U.S. 




U.S. 




Customary 




Customary 




Practice 


SI Practice 
DN6 


Practice 
NPS 20 


SI Practice 


NPS % 


DN500 


NPS % 


DN8 


NPS 22 


DN550 


NPS 3 / 8 


DN 10 


NPS 24 


DN600 


NPS \ 


DN 15 


NPS 26 


DN650 


NPS % 


DN20 


NPS 28 


DN700 


NPS 1 


DN25 


NPS 30 


DN750 


NPS \% 


DN32 


NPS 32 


DN800 


NPS \\ 


DN40 


NPS 34 


DN850 


NPS 2 


DN50 


NPS 36 


DN900 


NPS 2V 2 


DN65 


NPS 38 


DN950 


NPS 3 


DN80 


NPS 40 


DN 1000 


NPS 3 l / 2 


DN90 


NPS 42 


DN 1050 


NPS 4 


DN 100 


NPS 44 


DN 1100 


NPS 5 


DN 125 


NPS 46 


DN 1150 


NPS 6 


DN 150 


NPS 48 


DN 1200 


NPS 8 


DN200 


NPS 50 


DN 1250 


NPS 10 


DN250 


NPS 52 


DN 1300 


NPS 12 


DN300 


NPS 54 


DN 1350 


NPS 14 


DN350 


NPS 56 


DN 1400 


NPS 16 


DN400 


NPS 58 


DN 1450 


NPS 18 


DN450 


NPS 60 


DN 1500 



(h) Areas in square inches (in. 2 ) were converted to 
square mm (mm 2 ) and areas in square feet (ft 2 ) were con- 
verted to square meters (m 2 ). See examples in the follow- 
ing table: 



Area (U.S. Customary) 

lin. 2 

6 in. 2 

10 in. 2 

5 ft 2 



Area (SI) 

650 mm 2 

4 000 mm 2 

6 500 mm 2 

0.5 m 2 



(i) Volumes in cubic inches (in. 3 ) were converted to 
cubic mm (mm 3 ) and volumes in cubic feet (ft 3 ) were 
converted to cubic meters (m 3 ). See examples in the follow- 
ing table: 



Volume (U.S. Customary) 


Volume (SI) 


lin. 3 


16 000 mm 3 


6 in. 3 


100 000 mm 3 


10 in. 3 


160 000 mm 3 


5 ft 3 


0.14 m 3 



(j) Although the pressure should always be in MPa for 
calculations, there are cases where other units are used in 
the text. For example, kPa is used for small pressures. 
Also, rounding was to one significant figure (two at the 
most) in most cases. See examples in the following table. 
(Note that 14.7 psi converts to 101 kPa, while 15 psi 
converts to 100 kPa. While this may seem at first glance 
to be an anomaly, it is consistent with the rounding phi- 
losophy.) 



Pressure (U.S. Customary) 


Pressure (SI) 


0.5 psi 


3kPa 


2 psi 


15kPa 


3 psi 


20kPa 


10 psi 


70kPa 


14.7 psi 


101 kPa 


15 psi 


100 kPa 


30 psi 


200 kPa 


50 psi 


350 kPa 


100 psi 


700 kPa 


150 psi 


1 MPa 


200 psi 


1.5 MPa 


250 psi 


1.7 MPa 


300 psi 


2 MPa 


350 psi 


2.5 MPa 


400 psi 


3 MPa 


500 psi 


3.5 MPa 


600 psi 


4 MPa 


1,200 psi 


8 MPa 


1,500 psi 


10 MPa 



(k) Material properties that are expressed in psi or ksi 
(e.g., allowable stress, yield and tensile strength, elastic 
modulus) were generally converted to MPa to three sig- 
nificant figures. See example in the following table: 



Strength (U.S. Customary) 
95,000 psi 



Strength (SI) 
655 MPa 



(7) In most cases, temperatures (e.g., for PWHT) were 
rounded to the nearest 5°C. Depending on the implied 
precision of the temperature, some were rounded to the 
nearest 1°C or 10°C or even 25°C. Temperatures colder 
than 0°F (negative values) were generally rounded to the 



224 



2007 SECTION IV 



nearest 1°C. The examples in the table below were created 
by rounding to the nearest 5°C, with one exception: 



Temperature, °F 

70 

100 

120 

150 

200 

250 

300 

350 

400 

450 

500 

550 

600 

650 

700 

750 

800 

850 

900 

925 

950 
1,000 
1,050 
1,100 
1,150 
1,200 
1,250 
1,800 
1,900 
2,000 
2,050 



Temperature, °C 

20 

38 

50 

65 

95 
120 
150 
175 
205 
230 
260 
290 
315 
345 
370 
400 
425 
455 
480 
495 
510 
540 
565 
595 
620 
650 
675 
980 
1040 
1095 
1 120 



by the factor given to obtain the SI value. Similarly, divide 
the SI value by the factor given to obtain the U.S. Custom- 
ary value. In most cases it is appropriate to round the 
answer to three significant figures. 



U.S. 








Customary 


SI 


Factor 


Notes 


in. 


mm 


25.4 




ft 


m 


0.3048 




in. 2 


mm 2 


645.16 




ft 2 


m 2 


0.09290304 




in. 3 


mm 3 


16,387.064 




ft 3 


m 3 


0.02831685 




U.S. gal 


m 3 


0.003785412 




U.S. gal 


liters 


3.785412 




psi 


MPa 


0.0068948 


Used exclusively in 




(N/mm 2 ) 




equations 


psi 


kPa 


6.894757 


Used only in text 
and for nameplate 


psi 


bar 


0.06894757 




ft-lb 


J 


1.355818 




°F 


°C 


% X (°F - 32) 


Not for temperature 
difference 


°F 


°C 


% 


For temperature 
differences only 


R 


K 


% 


Absolute temperature 


lbm 


kg 


0.4535924 




lbf 


N 


4.448222 




in.-lb 


N-mm 


112.98484 


Use exclusively in 
equations 


ft-lb 


N-m 


1.3558181 


Use only in text 


ksi^/m 


MPaTm 


1.0988434 




Btu/hr 


W 


0.29230711 


Use for boiler rating 
and heat transfer 



lb/ft 3 



kg/m 3 



16.018463 



M-3 



SOFT CONVERSION FACTORS 



The following table of "soft" conversion factors is pro- 
vided for convenience. Multiply the U.S. Customary value 



225 



2007 SECTION IV 



NONMANDATORY APPENDIX N 

GUIDE TO MANUFACTURER'S CERTIFICATE OF 

CONFORMANCE FOR PRESSURE RELIEF VALVES 



INTRODUCTION 



The following pages are a guide for completing the 1. Numbers without circles appearing in the guide material 
Manufacturer's Certificate of Conformance Form HV-1. identify specific lines on the Manufacturer's Certificate 

of Conformance Form. 

Forms appearing in this section may be obtained from 
CD Circled numbers refer to the guide for required subject the ASME Order Department, 22 Law Drive, Box 2300, 
material. Fairfield, NJ 07007-2300. 



226 



2007 SECTION IV 

INSTRUCTIONS FOR THE PREPARATION OF SECTION IV MANUFACTURER'S 
CERTIFICATE OF CONFORMANCE FORM HV-1 

Note 

No. Instruction 

© Name and address of Manufacturer. 

© Pressure relief valve Manufacturer's unique identification number, such as serial, work order number, 
or lot number. 

© The date of completion of production of the pressure relief valve. 

The NB Certification Number. 

© The quantity of identical valves for this line item. 

© The Manufacturer's Design or Type Number as marked on the nameplate. 

© The inlet size of the pressure relief valve (NPS). 

© The nameplate set pressure of the pressure relief valve. 

© The nameplate capacity of the pressure relief valve. 

© The fluid used for testing the pressure relief valve. 

© The year built or the pressure relief valve Manufacturer's date code. 

© The Name of the Certified Individual. 

© The signature of the Certified Individual. Required for each line item. 

© The Number of the pressure relief valve Manufacturer's Certificate of Authorization. 

© Expiration Date of the pressure relief valve Manufacturer's Certificate of Authorization. 

© Date signed by the pressure relief valve Manufacturer Authorized Representative. 

© The Certificate of Shop Compliance block is to show the name of the Manufacturer as shown on his 
AS ME Code Certificate of Authorization. This should be signed in accordance with the organizational 
authority defined in the Quality Control System. 

© Include any applicable remarks (referencing the identification number) that may pertain, such as 
identification of a Code Case that requires marking on the device. 



227 



2007 SECTION IV 



FORM HV-1 MANUFACTURER'S CERTIFICATE OF CONFORMANCE FOR PRESSURE RELIEF VALVES 
As Required by the Provisions of the ASME Boiler and Pressure Vessel Code Rules 



1. Manufactured by 

2. Table of Code symbol stamped items: 



© 



I.D.# 


Date 


Cert. # 


Qty. 


Type 


Size 
(NPS) 


Set 
Pressure 


Capacity 


Test Fluid 


Date 
Code 


CI Name 


CI Signature 


© 


© 





© 


© 


© 


© 


© 


® 


© 


@ 


® 











































































































































































































































































3. Remarks 



© 



CERTIFICATE OF SHOP COMPLIANCE 

By the signature of the Certified Individual (CI) noted above, we certify that the statements made in this report are correct and that all 
details for design, material, construction, and workmanship of the pressure relief valves conform with the requirements of Section IV 
of the ASME BOILER AND PRESSURE VESSEL CODE. 



HV Certificate of Authorization No. 



© 



Expires 



© 



Date. 



© 



Signed . 



© 



Name. 



© 



(responsible representative) 



(manufacturer) 



(03/07) 



228 



2007 SECTION IV 



INDEX 



ASME Designee, HC-502.11 
Abbreviations and addresses, Appendix H 
Acceptance of unidentified materials (see Unidentified 

materials) 
Access doors, HG-330.1, HG-330.5 
Access openings, HG-330, HG-330.1, HG-330.4, HG-330.5, 

HG-720 
Accumulation test of safety and safety relief valve capacity, 

HG-512 
Addresses and abbreviations, Appendix H 
Adjusted pressure ratings for flanges and fittings, HG-370.2 
Admiralty plate, HF-301.2; Tables HF-300.2, HF-301.2 
Admiralty tubes, Table HF-300.2 
Air cushion in closed type expansion system, HG-709.2 
Airtight tank in closed type expansion system, HG-709.2 
Alignment (see Welded joints) 
Allowable stress values (see Stresses) 
Allowable working pressures (see Working pressures) 
Alloy steel (see Steel) 

Altitude gages for hot water boilers, HG-611 
American National Standard cast iron pipe flanges and flanged 

fittings, HC-310.1 
American National Standard steel pipe flanges and fittings, 

HG-370.2 
Anchorage, steam and hot water mains, HG-703.1; 

Figs. HG-703.1(a), HG-703.1(b), HG-703.2 
Application of Code, Preamble 
Assemblers and welders authorized, HG-533.1, HG-533.2, 

HW-610 
Assembly, boiler and boiler parts, by other than manufacturer, 
HG-533.2 

in field, HG-532, HG-533.1, HW-810 

of parts to be welded, HW-810 
Associated test bars (see Tests) 
Atmospheres and fluxes, HB-1103 
Atmospheric pressure, HG-300(b) 
Attachment material, strength of, HG-327.1, HG-327.2 
Attachments, of crown sheet to head or tubesheet, HW-712 

of firetubes and tube ends, HG-360.2 

of furnaces to head or tubesheet, HW-712, HW-715 

of head to shell, HW-715, HLW-415 

of tubes attached by rolling, HLW-309 

of tubesheets to shells, HW-711, HLW-411 

of tubes to tubesheets, HW-713, HLW-413 

strength, HW-703.1, HLW-430.1 

watertube, HW-731.8 



Attachments by welding (see Welding) 

Attachment welds (see Welds) 

Authorization for use of Code symbol, HG-540 

Authorization for use of materials not found in Section II, 

HG-200.3 
Authorized Inspector, HG-515.2-HG-515.4, HG-540 
Automatically fired boilers, flow-sensing device, HG-6 14(c) 
hot water, HG-611-HG-615 (see also Stamping) 
make-up water, HG-7 15(b) 

vertical firetube type, handholes or washout plugs for, 
HG-330.4(c) 
Automatic resetting pressure-temperature relief valve, 
HG-400.2 

Back strips, nozzles abutting boiler shell, HW-73 1.2(a), 
Fig. HW-73 1 
nozzles inserted in boiler shell, Fig. HW-731, HW-731.3(a) 
welded butt joints, HW-701.1, Fig. HW-701.1, HLW-401.1 
Baffles, materials for, HG-200.7, HF-202(b) 
Bars, associated test (see Tests) 

for alignment of welded parts, HW-8 10(b) 
specifications for, HF-202; Tables HF-300.1, HF-300.2 
stress values, maximum allowable, Tables HF-300.1, 
HF-300.2 
Base metal, preparation for welded joint, HW-801 
Basis for establishing stress values, Footnotes to 

Tables HF-300.1, HF-300.2 
Battery, boilers installed in, HG-703.1; Figs. HG-703.1(a), 

HG-703.1(b), HG-703.2 
Beading of firetubes, HG-360.2 
Blind flanges (see Flanges) 

Blowdown for safety and safety relief valves tests to determine 
pressures, HG-402.3(a) (see also Tests) (see also Safety 
and safety relief valves) 
Blowoff cocks, HG-715, Table HG-715 
Blowoff piping, HG-715, Table HG-715 
Blowoff valves (see Valves) 
Boilers, compact type, stamping of, HG-530.1(b) 
firetube type, manholes for, HG-330.2 
for service in excess of limits of this Section, HG-101.2 
horizontal tubular flue type, manholes for, HG-330.2 

stamping of, HG-530.1(b) 
inspection and certification of, HG-515 (see also 

Certification; Inspection) 
locomotive firebox type, handholes or washout plugs for, 
HG-330.4(a) 



229 



2007 SECTION IV 



stamping of, HG-530.1(b) 
scotch type, handholes or washout plugs for, HG-330.4(b) 

stamping of, HG-530. 1(b)(5) 
service restrictions and exceptions, HG-101, HG-101.1, 

HG-101.2 
setting, for wet-bottom type boilers, HG-720, HG-725.7 

outside suspension type, HG-725.2-HG-725.4 
split section and sectional firebox type, from 

wrought materials, stamping of, HG-530. 1(b)(4) 
stamping of, HG-530 (see also Stamping) 
vertical firetube type, handholes or washout plugs for, 
HG-330.4(c) 
stamping of, HG-530. 1(b)(2) 
watertube type, stamping of, HG-530. 1(b)(3) 
wet-bottom type, HG-720 
Bolted covers and heads (spherically dished) covers), HG-309, 

HG-309.1, Fig. HG-309 
Bolting flanges (see Flanges) 
Bolt loads, HG-307.1, HG-307.2 
Bolt moments, HG-307.2(b), HG-307.4 
Bosses, cast iron, radii of, HC-320 
Bottom blowoff piping and valves, size of, HG-715, 

Table HG-715 
Braces, as supports for heads or tubesheets, HW-711 

materials for, HF-202(a) 
Brackets for supporting boilers, HG-725, HG-725.6 
Brass, casting material, Table HF-300.2 
pipe, Table HF-300.2 

plates, HF-301.2; Tables HF-300.2, HF-301.2 
seamless condenser tubes, Table HF-300.2 
tubes, Table HF-300.2 
Brazed connections and fittings, HB-1307 
Brazed joints, cleaning, HB-1400, HB-1401 
clearance, HB-1305, Table HB-1305 
efficiency factors, HB-1301, HB-1304(a)(b) 
lap, testing of, HB- 1202. 1(b) 
post operations on, HB-1401 
rejection of, HB-1503(c)-(f) 
repair of defective, HB-1402, HB-1503(b)-(f) 
strength of, HB-1300 

visual examination of, HB-1503 (see also Joints) 
Brazers and brazing operators, certification of, HB-1502 
no production without qualification of, HB- 1202.3 
qualification of, by tests, HB- 1202.2, HB- 1202.4 
records of qualifications and identifying marks of, 

HB- 1202.4, HB- 1502(b) 
responsibility of manufacturers for, HB-1001, HB-1202.2, 

HB-1202.4 
symbol to identify work of, HB-1202.4 
Brazing, filler metal, design of joint to provide for application 
of, HB-1304 
flow of, HB-1304 
manual application of, HB- 1304(a) 
preplacement of, HB- 1304(b) 



materials, Code qualification of, HB-1100-HB-1103 
Code specifications and limitations of, HB-1100 
dissimilar, combinations of, HB-1101 
filler metals, HB-1102, HB-1304 
fluxes and atmospheres, HB-1103 
procedures, Code qualification and specifications of, 
HB-1001, HB-1202, HB-1202.1, HB-1303 
combination of welding and brazing in same assembly, 

HB-1201 
for each different type of joint, HB-1201 
inspection of, HB-1501 

no production without Code qualification of, HB- 1202.3 
recommended form of recording, HB-1201 
records of, HB-1201, HB-1202.4 
responsibility of manufacturer, HB-1001, HB-1202.1 
service temperature, permissible, HB-1303 
tests, qualification, HB-1001, HB-1202.1 
processes, HB-1200 
sequence, HB-1201 
Brittle coating of critical area in proof tests, HG-501.5, 

HG-502.4 
Bronze casting materials, Table HF-300.2 
Brown furnaces, HG-312.6 
Btu of various fuels, B-102 

Bursting pressure tests for pressure parts, HG-502.3 
(see also Tests) 
Butt joints (see Welded joints) 

"C" factors, values of, for unstayed heads, cover plates and 
blind flanges, HG-307.1, HG-307.2(b), HG-307.3, 
HG-307.4, Fig. HG-307 

Capacities, of bottom blowoff piping, HG-715, Table HG-715 
of expansion tanks, HG-709.3 

in forced hot water systems, Table HG-709.2 
in gravity hot water systems, Table HG-709.1 
relieving, of safety and safety relief valves (see Safety and 
safety relief valves; Valves) 

Capacity tests (see Tests; Valves) 

Carbon steel, Table HF-300.1 
bars and stays, HF-202, Table HF-300.1 
bolting, HF-202, Table HF-300.1 
castings, HF-203.1, HF-203.2, Table HF-300.1 
electric resistance welded pipe and tubes, Table HF-300.1 
forgings, HF-203.1, HF-203.2, Table HF-300.1 
furnaces, horizontal cylindrical, Figs. HG-312.1, HG-312.2 
permissible carbon content in weldments, HW-500(a) 
plate, HF-205, Table HF-300.1 
seamless pipe and tubes, HF-205, Table HF-300.1 

Castings, boiler, stamping of, HG-530.2 
pumps, HF-203.1 

Casting, parts formed by, HF-203.1, HF-203.2 

Castings, brass and bronze, Table HF-300.2 
steel, HF-203.1, HF-203.2, Table HF-300.1 

Cast iron, boilers, certifying tests, HC-403 



230 



2007 SECTION IV 



Code requirements, HC-100 

design of, HC-300, HC-310, HC-311, HC-315, HC-320, 

HC-325 
inspection, HC-501 
marking requirements for, HG-530.2 
quality control, HC-501 
recording of tests, HC-403 
washout openings for, HC-325 

washout openings used as return pipe connections, HC-325 
washout plugs, HC-325 
witnessing tests for, HC-403 
circular spherically shaped covers or heads, with bolting 

flanges, HC-311, HC-311.1, Fig. HC-311 
classes of, Table HC-300 
facings and drillings of flanges, HC-311.1 
flanges, HC-311, HC-311.1, Fig. HC-311, HC-3 15(b) 
for boilers and boiler parts, HC-100, HC-200, HC-300, 

Table HC-300 
heads, HC-310, HC-311 

minimum tensile strength values, Table HC-300 
nozzles, HC-315 

openings in cast iron boilers, HC-315 
pressure parts, HF-203.1, HF-203.2 
reinforcement of openings in cast iron boilers, HC-315 
stress values, maximum allowable, HC-300, Table HC-300 
washout openings in steam and hot water boilers, HC-325 
Cast nonstandard pressure parts, HF-203.2 
Cast standard pressure parts, HF-203.1 
Cast steel {see Castings, steel) 
Cement lined water heaters, HLW-200 
Certificate of Authorization to use Code Symbol Stamps, 
application for, HG-402.2 
authorization by Society, HG-402.2, HG-540, HG-540.1, 

HG-540.2(b) 
cancellation of certificate, HG-402.2, HG-540.2(c) 
expiration of certificate, HG-402.2, HG-540.2(c) 
fee paid by applicants, HG-402.2, HG-540.2(c) 
new regulations for, by Boiler and Pressure Vessel 

Committee, HG-402.2, HG-540.2 
purchase of symbol from Society, HG-402.2, HG-540.2 
refusal to renew, HG-402.2, HG-540.2(c) 
renewal of, HG-402.2, HG-540.2 
Certification, of brazers and brazing operators qualification test 
records, by manufacturers, HB- 1502(b) 
of field assemblies, by assemblers, HG-533.2 

by inspectors, HG-533.2 
of shop assemblies by manufacturers and inspectors, 

HG-515.3, HG-532.2 
of welders and welding procedure qualifications by 

manufacturers, HW-910, HW-911 
of work done by other than manufacturers, HG-515.1 
Certification by manufacturers, of records of Code 

qualification tests of brazers, of records of performance 
tests of welders and welding operators, HW-9 11(a) 



of records of welding procedures and welders, welding 
operators and their identification marks, HW-613 

of standard pressure parts as to material and service rating, 
HF-203.1, HF-203.2 

of tests of cast iron boilers and boiler parts to establish 
pressure rating, HC-403 

of tests of nonidentified material, HF-205.3 
Chambers, float, HG-606(a) 

of fuel cutoff and water feeding devices, HG-606(c) 

rear combustion, HG-330.4(b) 
Check valves in feed pipes, Fig. HG-703.1 
Circuit breakers and shutdown switches, location of, HG-634 
Circuitry, type of electric control, HG-632 
Circular cast iron spherically shaped covers {see Covers) 
Circular furnaces, plain type, HG-312.1 
Circular sections, plain, of combination type furnace, 

HG-312.6, Fig. HG-312.6 
Circular spherically dished heads {see Covers) 
Circulating system of boiler, standard pressure parts for, 

HF-203.1(a) 
Circumferential joints {see Joints) 
Clamps for aligning parts to be welded, HW-8 10(b) 
Cleaning, of surfaces to be brazed, HB-1400, HB-1401 

openings for, HG-330.1, HG-330.4, HC-325 

return piping, HG-703.2(d) 

water column piping, HG-604(a) 

water gage glasses, HG-603(a) 
Clearance, brazed joint, HB-1305 
Cocks, blowoff, HG-715 

gage, HG-601,HG-611 

stop valve, HG-710.4 
Code, jurisdictional limits, HG-101.1, HG-101.2, HG-101.3 

stamps {see Stamping; Stamps) 
Code compliance, electric wiring, HG-631, HG-640 
Code policy on new materials, A- 100 
Coefficient method, capacity relieving tests {see Tests) 
Coils, pipe, for heating hot water supply, HG-400.3(a) 

in heat exchangers, HG-400.3(b)(c) 
Cold bending and close coiling, materials suitable for, 

HF-205.2(b) 
Collapse tests of pressure parts {see Tests) 
Columns, fluid relief, HG-709 

water, HG-603, HG-604(a)(b), HG-705 
Combination type furnaces, requirements for, HG-312.7, 

Fig. HG-312.6 {see also Furnaces) 
Common connections of two or more valves, requirements for, 

HG-701.2 {see also Safety and safety relief valves) 
Compensation, limits in cylindrical shells, Fig. HG-320 
Component parts requiring proof testing {see Tests) 
Cones, openings in, HG-32 1.2(b) 

thicknesses of, HG-321.2(b) 
Conical portions of boilers, openings in, HG-320. 1 
Connections, area of, for two or more safety valves, 
HG-701.2(a) 



231 



2007 SECTION IV 



attached to shells, drums, headers by welding (see Welded 

connections) 
blowoff, HG-705, HG-715(a)(b) 
bolted, HG-309, Fig. HG-309, HG-370.2, HC-310.1, 

HC-311, Fig. HC-311 
bottom blowoff and/or bottom drain (see Connections, 

blowoff) 
brazed, HB-1306, HB-1307 
common, for separate combustion controls, HG-605, 

HG-613 
for two or more safety relief valves, requirements of, 
HG-701.2 
couplings, pipe, welded to brazed boilers, HB- 1306(b) 
discharge or drain piping, HG-715, Table HG-715 
elbows, to safety or safety relief valve discharge pipe, 

HG-701.6 
expanded, HG-320.3(c), HG-360.1, HG-360.2 
external piping, flanged, HG-370.2 

threaded, HG-370.1, Table HG-370 
feedwater, HG-705 

flanged, for external piping, HG-370.2 
flared, for tube ends, HG-360.1, HG-360.2 
flow, of hot water boilers, HG-6 11(a) 
for altitude gages, HG-6 11(a), (c) 
for controls, HG-605, HG-605(c), HG-613 
for pressure gages, HG-605, HG-6 11 
for steam gages, HG-601-HG-604 
for test gages, HG-505, HC-402.1 
fuel cutoff, to boilers, HG-606(b) 
inlet, of safety valves, HG-701.2 
nozzles (see Nozzles) 
of piping to boilers, HG-370.1, HG-370.2, Table HG-370, 

HG-703.1, HG-703.2, HG-705, HG-707 
outlet, for damper or feedwater regulator, HG-604 
return pipe or piping, HG-703.2, HG-705, HG-710, 

HG-710.2, HG-710.3, HC-325 
saddle type fittings (see Fittings) 
saddle type pads, welded, HW-731.5, Fig. HW-731(k) 
studded, HG-320.3 
supply pipe, for multiple boilers, Figs. HG-703.1, 

HG-703.2; HG-710.3 
for single hot water boilers, HG-710.2 
for single steam boilers, HG-710.1 
threaded, for external piping, HG-370, HG-370.1, 

Table HG-370 
for valves, HG-701.3 
size of, HG-320.3(c)(l) 
to safety and safety relief valves, HG-701, HG-705 
to tapped openings, HG-370.1 
water column, HG-604, HG-705 
water equalizing pipe, HG-606(c) 
water feeding devices, HG-606(b) 
water gage glass, HG-603, HG-604, HG-705 
water level control piping, HG-604, HG-605, HG-705 



water treatment, HG-705 

welded, HW-730, HW-731.1, HW-731.5, Fig. HW-731 
location and minimum size of, HW-731.1 
maximum size of unreinforced, HG-320.3(c)(2) 
Contraction, provision for (see Expansion and contraction) 
Contractor's responsibility (see Manufacturer's responsibility 
Control panel frame (control circuitry), HG-632 (see also 

Electric wiring) 
Controls, altitude gage, for hot water boilers, HG-6 11 
automatic low-water fuel cutoff, HG-606 
combustion, for steam boilers and multiple boiler 

installations, HG-605 
damper regulator, HG-602 
electric, HG-631, HG-632 

limit, HG-633 
feedwater regulator, HG-604 
flame safeguard, HG-640 
low- water fuel cutoff, HG-6 14 
mounted inside boiler jackets, HG-621 
operating, for automatically fired boilers, HG-605(a), (b); 

HG-6 13(a), (b) 
piping, water level, HG-604 
pressure, HG-605 

operating, HG-605(b) 
pressure-actuated combustion, HG-605(a), (b) 
primary safety, HG-640 
safety, for heat generating apparatus, HG-640 
temperature-actuated combustion, HG-613(a), (b); 
HLW-801.1 
Copper, fittings, assembled with copper or copper alloy tubes, 
HG-3 15.2(b) 
parts, maximum allowable stress values, Table HF-300.2 
minimum thicknesses of, HF-301.2, Table HF-301.2, 

HB-1302 
staybolts, HG-342.6 
Copper alloy (see Copper) 
Copper lined water heaters, HLW-200 
Copper-nickel (see Copper) 

Cored sections of cast iron boilers stamping of, HG-5 30.2(a) 
Corner or tee joints (see Joints) 
Corner radius, HG-307.1, HG-307.4, HG-340.1 
Corners and fillets, cast iron boilers, HC-320 
Corner welds (see Welds) 

Corrugated furnaces, HG-3 12.6 (see also Furnaces) 
Corrugated sections, HG-3 12.7 (see also Furnaces) 
Counterboring of tube holes, HG-360.1 
Couplings, pipe (see Connections) 
Courses in steel plate boilers, HG-320.2(c), HW-701.1 
Cover plates, minimum thicknesses of (see Covers) 
Covers, HG-307.1, HG-307.2(b), HG-307.3, HG-307.4, 

Fig. HG-307, HG-309, Fig. HG-309 
Crimping, HG-307.4, HB- 1305(b) 
Critical areas, pressure parts, HG-501.5 
Crown radius, HG-305.3, HG-305.6, HG-309 



232 



2007 SECTION IV 



Crown sheets, HW-712.1, HW-712.2 

external pressure, HG-312.7 
Curves, plotted during displacement pressure measurement 
tests, HG-502.2 (see also Tests) 

plotted during strain pressure measurement tests, 
HG-502.1(c) (see also Tests) 
Cutoff, automatic low- water fuel, HG-606, HG-614 
Cutting, flame, for test specimens, HG-501.6(b) 

of base metal, HW-801 

oxygen, of text specimens, HG-501.6(a), HW-500(a) 

thermal, of plates, HW-500, HW-801 
Cylindrical parts under external pressure, HG-312 

furnaces, HG-312.1-HG-312.3, HG-312.5, HG-312.6, 
Figs. HG-312.1, HG-312.2 (see also Furnaces) 
Cylindrical portions of boilers, HG-320.1, HG-320.2 
Cylindrical pressure parts, groups of openings in, HG-350.1 
Cylindrical shells, alignment tolerances of plate edges, 
HW-812 

joined to stayed wrappers, HW-701.2 

openings in, HG-320.2, HG-321.1(a) 

under internal pressure, HG-301 



Damper regulators in water piping, HG-604 
Data Reports, assemblers', HG-533.2, HG-533.3 

for field assembled wrought boilers, HG-532, HG-532.1, 

HG-532.2, Forms H-2, H-3 
Forms, manufacturer's Data Reports for all types of boilers 

except watertube and cast iron, Form H-2 
manufacturer's Data Report for water heaters or storage 

tanks, Form HLW-6, HLW-601.1 
manufacturer's Data Reports for watertube boilers, 

Form H-3 
manufacturer's master, for cast iron boilers, HC-403, 

HC-405, Form H-5 
manufacturer's master Data Proof Test Report for water 

heaters or storage tanks, Form HLW-8 
manufacturer's master, for wrought boilers, HG-520, 

HG-520.1, Forms H-2, H-3 
manufacturer's master Data Reports for boilers constructed 

from cast iron, Form H-5 
manufacturer's Partial Data Reports, Form H-4 
manufacturer's Partial Data Report for water heaters and 

storage tanks, Form HLW-7 
partial, HG-520.2, Form H-4, HLW-601.2 

not required, HF-203, HF-203.1-HF-203.3 
for safety and safety relief valve tests, HG-402.9 
Deadweight tester, standard, HG-505(c), (see also Tests) 
Defects, in brazed joints, HB-1402, HB-1501, HB-1503 

in welds and welded joints, HW-830 
Definitions, E-100, E-101 
Deformation, radial, in threaded joints, HG-307.4 

tests, HG-503 
Design pressure, HG-300(a) 



Design stress criterion, Footnotes to Tables HF-300.1, 

HF-300.2 
Design stresses, Article 3, Tables HF-300.1, HF-300.2 
Destruction tests, HC-402 
Deterioration, internal parts subject to, HG-200.2 
Devices, automatic low-water fuel cutoff and/or water feeding, 

HG-606 
lifting, for safety and safety relief valve disks (see Disks) 
Diagonal lines, holes along, HG-350.4, Fig. HG-350.4 (see 

also Holes; Openings) 
Diagonal pitch, of adjacent openings, HG-350.1 (see also 

Holes; Openings) 
Diagonal stays, area required of, HG-343.1 
dimensions of, HG-343, Fig. HG-343 
for segments of tubesheets, HG-343. 2 
welding of, HW-710.4 
Dials, graduated for gages (see Gages) 
Die formed nonstandard pressure parts, HF-203. 2 
Die formed standard pressure parts, HF-203. 1 
Die forming process, HF-203. 1, HF-203.2 
Dip brazing, HB-1200, HB- 1202.2 

Discharge capacities, safety and safety relief valves, HG-402 
discharge in Btu (safety relief valves, Table HG-715 
identifying markings, HG-402. 1 
tests, pressure and relieving capacity, HG-402.3, HG-402.5 

coefficient method, HG-402.3(a) 

curve method, HG-402.3(b) 

fluid medium for, HG-402.7 

pressures at which conducted, HG-402.4 

three-valve method, HG-402.3(c) 

where and by whom conducted, HG-402. 8 
Discharge piping, blowoff, HG-715 

safety and safety relief valves, arrangement to prevent 
scalding of attendants, HG-701.6(b), HLW-801.7 

draining of, HG-701.6(b) 

elbows, location of, HG-701.6(a) 

internal cross-sectional area of, HG-70 1.6(a) 

shutoff valves in, HG-701.5 

size and arrangement of, HG-70 1.6(b) 
Dished heads (see Heads) 
Disks, safety and safety relief valve lifting devices for, of 

corrosion resistant 
Displacement measurement tests of pressure parts, HG-502.2 
Dissimilar metals, brazing of, HB-1101 
Distortion, HW-813 
Doors, access, HG-330.1(b), HG-330.5 
Double-welded butt joints (see Welded joints) 
Double-welded lap joints (see Welded joints) 
Drain cocks, HG-715 
Drain connections, HG-715 

Draining of single hot water heating boilers, HG-710.2 
Drain pipe connections, HG-606(c), HG-715, HLW-8 10 
Drains, open gravity, in safety valves, HG-400.1 



233 



2007 SECTION IV 



Drain valves, in bottom blowoff pipe connections in boilers, 
HG-715, HLW-810 

in water column piping, HG-604(a) 
Drilled holes in furnace sheets, HG-312.6 
Drilled telltale holes in solid staybolts, HG-341.1 
Drilled tube holes, HG-360 
Drilling and facing of flanges, HG-309, HC-312.1, 

Fig. HC-311 {see also Flanges) 
Drillings, chemical composition, HC-202 
Drums, circular or noncircular plates welded to inside of, 
HG-307.4 

connections to, welded, Fig. HW-731 

fusion welded boiler, HG-307.4, HW-701.1 
Ductility of material submitted for Code approval, A- 103 
Duplicate pressure parts, hydrostatic tests of, HG-504 
Dye penetrant inspection of brazed joints, HB- 1503(c) 

Edges, of tube holes, HG-360. 1(b) 

of plates offset from each other, HW-812 
Efficiencies, joint, HG-301, HG-305.1, HW-702 
brazed, HB-1301 
welded, HW-702 
Efficiency, ligament, HG-301, HG-350.1-HG-350.4 
Efficiency factors of brazed joints in design of boilers, 

HB-1301, HB-1304, HB-1503(a) 
Elbows, in safety or safety relief valve discharge pipes, 

HG-70 1.6(a) 
Electrical code compliance, HG-631, HG-632(a)(l), HG-640, 

HLW-704.1 
Electrically heated boilers, HG-101.2, HG-640(a) 
Electric resistance brazing process, HB-1200, HB-1202.2 
Electric resistance welded pipe and tubes, Table HF-300.1 
Electric wiring, field or factory mounted, circuitry for, 
HG-632, HLW-704 
compliance with National Electric Code and/or local codes, 

HG-631, HLW-704.1 
for controls, heat generating apparatus, and other boiler 

appurtenances, HG-631, HLW-703 
limit controls, HG-633, HLW-702 
shutdown switches and circuit breakers, HG-634 
Elements, thermal, for pressure-temperature relief valves, 

HG-405 
Ellipsoidal formed heads {see Heads) 
Elliptical flat unstayed heads, covers, and blind flanges, 

HG-307.3 
Elliptical manholes {see Manholes) 

Elongation in material submitted for Code approval, A-101(a) 
Ends, of firetubes in contact with primary furnace gases, 
HG-360.2(a) 
of firetubes not in contact with primary furnace gases, 

HG-360.2(b) 
of nipples, HG-606(b) 
of plates, forming, HW-800 
of staybolts, fitted with nuts, HG-341.3 



of steel stays, upset for threading, HG-341.2 
of through-stays with washers, HG-340.2, Fig. HG-340.2 
of tubes, flared to fit tube holes, HG-360. 1 
Examination of cast iron boilers, HC-510 
Examination, visual, of brazed joints, HB-1301, HB-1304, 

HB-1503 
Examples of methods, of calculating a welded ring reinforced 
furnace for steam or hot water boilers, C-100, C-101 
of checking safety and safety relief valve capacity by 

measuring minimum amount of fuel that can be burned, 
B-101 
of computation of openings in boiler shells, D-100, Fig. D- 
100, D-101 
Exchanges, heat, safety valve requirements for, HG-400.3 
Expanded connections, HG-320.3(c)(l) 
Expanding of tube ends, HG-360. 1(a), HG-360.2(a) 
Expansion, thermal, in hot water systems, HG-709, HG-709.2 
Expansion and contraction, in piping connected to boilers, 
HG-703.1, HLW-809.2, Figs. HG-703.1, HG-703.2, 
HLW-809, HLW-809.1 
Expansion tanks, HG-709, HLW-809 

capacity of closed, HG-709.3, Tables HG-709. 1, HG-709.2 
closed, HG-709.3 
draining provisions, HG-709.2 
open, overflow for, HG-709. 1 
External piping connections, HG-370 
flanged, HG-370.2 
threaded, HG-370. 1 
External pressure, crown sheets, HG-312.8 

materials for, submitted for Code approval, A- 101(b) 
semicircular furnaces, HG-312.8 {see also Pressure) 
External supports, HG-200.7, HF-202 
External type oil heater, HG-707 

F values of, in calculating required reinforcement, 

Fig. HG-321 
Fabrication of boilers and boiler parts by brazing, HB-1000 

by welding, HW-400 
Facings and drillings of flanges, cast iron, conforming to 
American National Standards, HC-3 11.1 
steel, conforming to American National Standards, 
HG-309. 1 
Fee, for use of Code Symbol, HG-402.2, HG-540.2(b) 
Feedwater, connections, HG-606, HG-705 
devices, HG-606 
introduced directly to boiler through independent 

connections, Fig. HG-703.1 (Note) 
introduced through return piping or through independent 

connections, HG-705 
regulators, HG-604 
Ferrous materials, maximum allowable stresses, 
Tables HF-300.1, HC-300 
specifications for, Tables HF-300.1, HC-300 
Field assembled boilers and boiler parts 



234 



2007 SECTION IV 



inspection, stamping and Data Reports, HG-532.1, 

HG-532.3, HG-533.1, HG-533.2, HG-533.3, HG-533.6 
inspection and certification of, HG-533.3, HG-533.6 
Filler metals, for brazing, application of, HB-1304 
control of, in repair of brazed joints, HB-1402 
defects in, HG-1503 

distribution of, by capillary attraction, HB-1305 
face feeding of, in brazed joints, HB- 1304(a) 
in construction of brazed boilers, Code requirements of, 

HB-1103 
preplacement of, HB- 1304(b) 
qualification of, HB-1303 
service temperature of, HB-1303 
strength of, HB-1300 
for welding (see Weld metal) 
Fillets, and corners, cast iron, HC-320 
and transition section, HC-320 
rough, in brazed joints, HB-1503 
Fillet-welded lap joints (see Welded joints) 
Fillet welds (see Welded joints, Welds) 
Finish of material submitted for Code approval, A- 105(d) 
Fireboxes, pitch of staybolts, Fig. HG-340. 1 
Firebox type boilers, HG-330.4 

locomotive, HG-530.2 
Fire doors, HG-330.5(b) 

Firetube boilers, location of manholes, HG-330.2 
Firetube vertical boilers, handholes and washout plugs in, 

HG-330.4 
Fittings, attached by brazed lap joints, HB- 1307(a) 
couplings, pipe, welded, in brazed boilers, HB- 1306(b) 
crosses, HG-604(a) 
dimensions, HG-370.2, HG-602-HG-606, HG-611, 

HG-701.2, HW-731, Fig. HW-731, HB-1306, HC-320, 
HC-325 
elbows on safety and safety relief discharge pipe, 

HG-70 1.6(a) 
external piping connections, flanged and threaded, HG-370 
flanged external piping connections, HG-370.2 
for hot water boilers, HG-610-HG-615 
for steam heating boilers, HG-601-HG-607 
inside boiler jackets, HG-620, HG-621 
internal threads, HLW-431.5 
in water piping connections to boilers, HG-604(a) 
material of, HG-200.1, HG-201, HG-315, HF-202, 

HF-203.1-HF-203.3, Table HC-300 
nipples, for safety valve mountings, HG-701.1 

reaming of, HG-606(b) 
nonferrous, tees and Y's between boilers and water glasses, 

HG-606 
nozzles, cast, forged, rolled, or die formed, HF-203.1 
cast iron, cast integrally, HC-3 15(b), HC-320 
strength of, and added material, HG-327.1 
welded, abutting boiler well, HW-73 1 .2 



attached by arc or gas welding, HW-730.1, HW-73 1.1, 

Fig. HW-731 
attachment welds for, location and size, HW-73 1.1 
attachment welds for, stress values of, HG-327.1, 

HW-730.2 
inserted, with added reinforcement, HW-73 1.4, 

HLW-431.3 
inserted, without reinforcement, HW-73 1.3, 

HLW-431.2 
material requirements, HG-203.3 
some acceptable types of, Fig. HW-731 
with integral reinforcement, HW-73 1.5, HLW-431.2 
with bolting flanges or integral flanges to be brazed, 
HB- 1307(b) 
saddle type, for outwardly flanged openings in brazed vessel 

wall, HB- 1307(a) 
steel, HF-203.1 
threaded plugs in bottom of corrugated furnace, 

HG-3 12.6(c) 
valved, to connect water glasses to steam boiler water 

columns, HG-602 
washout plugs, dimensions and locations of, HG-330.1, 

HG-330.4, HC-325 
water glasses, attached directly to boiler, HG-603, HG-606 
welded, internally threaded, HW-73 1.6, Fig. HW-731 
material requirements, HF-203.3 
Fit-up and welding of stays, HW-710.3 
Flange, bolted, connections, HG-370.2 
Flanged heads, Fig. HG-307, HG-345.2, HW-711.1 
Flanged-in manhole openings, HG-323.3(a) 
gasket bearings surface, HG-323.5 
in heads in horizontal firetube boilers, HG-345.1(d) 
Flanged-in openings in formed heads, HG-323 
Flanged openings, connected to safety and safety relief valves, 

HG-701.1 
Flanged plates, screwed over end of shell, pipe, or header, 

thickness of, HG-307.4, Fig. HG-307 
Flange rings, HF-202 

for spherically dished covers (bolted heads), HG-309 
Flanges, blind, thickness of, HG-307.2-HG-307.4; 
Figs. HG-307(j), (k) 
cast integrally with cast iron boilers, HC-3 15, HC-320 
in brazed connections to boilers, HB- 1307(b) 
integral, HG-309, Fig. HG-309, HC-3 10, HC-3 15, HC-320 
welded, HF-203.1 
Flanging, outward, of vessel walls, HB-1307 
Flared rings, HG-3 12.4, Fig. HG-3 12.3 
Raring of firetubes, HG-360.2 
Flash welding process, HW-600(b) 
Rat heads (see Heads) 

Flat plates, edges of stayed, flanged, HG-340.5(c) 
staybolts, for, HG-341, HG-342.6 
with stays, HG-340. 1 
Flat spots on formed heads, HG-305.9 



235 



2007 SECTION IV 



Flat surfaces, on dished heads, HG-305.9 
on formed or flat heads, permissible diameters of, HG-305.9 
on stayed formed heads, HG-305.5 
to be stayed, HG-340.1, Fig. HG-340.1 
welded joints in, between two rows of stays, HG-340.5 
Float chambers, HG-606(a) 
Flow, connections on hot water boilers, HG-611(a) 
of brazing filler metal into or across joints, HB-1304 
steam, actual, formula for coefficient of discharge, 

HG-402.3(a) 
steam, theoretical, formula for coefficient of discharge, 
HG-402.3(a) 
Flowmeter, steam, HG-402.7 
Flues, as stays of flanged-in openings, HG-323.3(a) 
circular, in water heaters, HLW-307.1 
in horizontal tubular flue type boilers, stamping of, 
HG-530.2(a)(l) 
Fluid medium, for capacity tests of safety relief valves, 

HG-402.7 
Fluid relief columns, in hot water heating systems, HG-709 
Fluing operation, HG-305.1 (Note 1) 
Fluorocarbon polymer lined water heaters, HLW-200 
Fluxes and atmospheres, HB-1103 

residue, removal of, HB-1401, HB-1503(a) 
Forced hot water systems, HG-709, Table HG-709.2 
Forging materials, Table HF-300.1 

Forgings, carbon steel, specifications and material properties, 
Table HF-300.1 
nonstandard pressure parts, HF-203.2 
standard pressure parts, HF-203.1 
Formed heads (see Heads) 
Forming, die, of nonstandard pressure 
parts, HF-203.2 

of standard pressure parts, HF-203.1 
fabrication practice, on material submitted for Code 
approval, A- 103 
Forms, Data Report, manufacturer's, for all types of boilers, 
except hot watertube and cast iron, Form H-2 
for water heaters or storage tanks, Form HLW-6 
for watertube boilers, Form H-3 
master, for cast iron boilers, Form H-5 
partial, Form H-4 

for water heaters and storage tanks, Form HLW-7 
proof test report for water heaters or storage tanks, Form 

HLW-8 (see also Data Reports) 
recommended for recording brazing procedures, HB-1201 
Fox furnaces, corrugated type, HG-312.6 
Fracture, brittle, of material submitted for Code approval, A- 

103 
Frames, for reinforced openings, HF-202, Tables HF-300.1, 

HF-300.2 
Fuel, burning of, B-100-B-102 
Fuel burning equipment, HG-330.5(b), HG-400.1(e), 
HG-400.2(f) 



Fuel cutoffs, automatic low-water, HG-604(a), HG-606, 
HG-614 
high-limit temperature actuated, HG-613 
Fuels, heats of combustion of, B-102 
Furnace brazing, HB-1200 

Furnaces, access doors, HG-330, HG-330.1(c), HG-330.5 
access openings, fire doors, HG-330.5 

inspection, HG-330.4(b) 
attachments, HG-312.4, HW-712.1, HW-712.2 
Code stamping of, HG-530.1, HG-530.2 
combination type, for external pressure, HG-312.7 
corrugated type, HG-312.6, Fig. HG-312.6 
drilled holes in, to determine thickness, HG-312.6 
fire door openings in, HG-330.5(b) 
flared end assembly of plain type, HG-312.1 
Fox, corrugated type, HG-312.6 
horizontal cylindrical type, carbon steel charts for 
determining wall thicknesses of, Figs. HG-312.1, 
HG-312.2 
inspection openings for, in scotch type boilers, HG-330.4(b) 
Leeds suspension bulb, corrugated type, HG-312.6 
materials, HG-201, HF-201, HF-203 

ferrous, HF-300, HF-301.1, Tables HF-300.1, HF-301.1 
nonferrous, HF-300, HF-301.2, Tables HF-300.2, 
HF-301.2 
Morrison, corrugated type, HG-312.6 
plain circular type, requirements for, HG-312.1 
flared-end assembly of, HG-312.1(d) 
thickness of wall and procedure for determining, 

HG-312.1(d), HG-312.2, Figs. HG-312.1, HG-312.2 
Purves, corrugated type, HG-312.6 
ribbed type, thickness, calculation of, HG-3 12.6(c) 
ring reinforced type, HG-312.4, Fig. HG-3 12.3 
design temperature, HG-3 12.4(f) 

examples of methods of calculating welded, C-100, C-101 
replacement of, HG-312.4, Fig. HG-3 12.3 
stiffening rings, requirements for, HG-312.4, HG-312.5, 
Figs. HG-312.1, HG-312.2 
tubes, attached to tubesheets, HW-713 
wall thicknesses, corrugated or ribbed types, HG-3 12.6(c) 
plain types, HG-312.1, Figs. HG-312.1, HG-3 12.3 
procedure for determining, HG-3 12.3 
ring reinforced types, HG-3 12.4(a), (h) 
Furnace sheets, HW-712.1, HW-712.2 
Fuses, time delay, in control circuitry, HG-632(a)(3) 
Fusion of base metal, HW-701 
Fusion welding (see Welding) 

Gage cocks, for pressure or altitude gages, HG-611(a) 

for steam gages, HG-602(a) 
Gage connections, HG-602(a) 
Gage piping, HG-602(a) 
Gage pressure, definition, HG-300(b) 
Gage tubes and tubing, HG-602(a) 



236 



2007 SECTION IV 



Gages, altitude, HG-611 
compound steam, HG-601 
deadweight tester for, HG-505(c), HC-402.1(c) 
master, calibrated, HG-505(c), HC-402.1(c) 
pressure or altitude, for hot water boilers, HG-611, HG-621, 

HG-705 
steam, HG-602 
strain, HG-502.1(a) 

temperature, HG-612, HG-621, HG-705 
test, deadweight tester for, HG-505(c), HC-402.1(c) 
indicating, HG-505, HC-402.1 
master, HG-505(c), HC-402.1(c) 
recording, for larger vessels and pressure parts, 

HG-505(a), HC-402.1 (a) 
strain, HG-502.1 

water gage glasses for electric boilers, HG-603(c)(e) 
resistance heating, HG-603(d) 
submerged electrode, HG-603(c) 
water gage glases for steam boilers, HG-603(a) 
fittings, HG-603(a), HG-604(a), HG-606(b) 
lowest visible part of, HG-603(b) 
material of, HG-603(b) 
piping for, HG-604(a), HG-606(b), HG-705 
water gages, mounted inside boiler jackets, HG-621 {see 
also Steam gages; Test gages; Water gage glasses) 
Galvanized water heaters, HLW-200 
Gases, primary furnace, firetubes in contact with, HG-360.2 
furnaces or crown sheets in contact with, HW-712.2 
shells in contact with, HW-711.1, HW-711.2 
Gas, natural, fired boilers, HG-640 
Gaskets, for manholes, bearing surfaces, HG-323.5 
thicknesses of, HG-330.3(d) 
full face, for bolting flanges, HG-309.1, HC-311.1 

for circular and noncircular covers, HG-307.4 
moment arms of, HG-307.1 
rings, for bolting flanges, HG-309.1, HC-311.1 
tightness of, HG-307.2(b) 
Gas tungsten arc welding, HW-600 
Gas welding, HW-600 
Glands, for plug cocks, HG-710.4 
Glass-lined water heaters, HLW-200 
Gravity drains, open, in safety valve casings, HG-400.1(a) 
Gravity hot water systems, expansion tank capacities, 

Table HG-709.1 
Gravity return steam heating systems, HG-703.2, 

Fig. HG-703.1 
Grinding, of base metal before welding, HLW-801(a)(d) 

of ends of tack welds after welding, HW-8 10(c) 
Groove welds {see Welds) 
Ground conductors, in control circuitry, HG-632 
Guards, for plugs of plug cocks, HG-710.4 

H, authorized Code Symbol for stamping of both steam and 
water boilers, HG-530.2, Figs. HG-530.1-HG-530.3 



Hand-fired boilers, HG-703.2(b) 
Handholes, in all boilers, for inspection, HG-330. 1 
in boilers designed for steam service, for in bottom of 

shells, for inspection, HG-330.4(b) 
in front heads of scotch type boilers, HG-330.4(b) 
in locomotive or firebox type boilers, location of, 

HG-330.4(a) 
in scotch and scotch marine boilers, HG-330.4 
in vertical firetube or similar type boilers, HG-330.3(c) 
in size of, HG-330.4(f) 
Handles, T- or lever, HG-602(a), HG-6 11(a) 
Hangers to support boilers, HG-725.1, HG-725.6 
Headers, HG-301, HG-307.4, Fig. HG-307, HG-530.2, 

HG-604(b), HG-701.1, HW-73 1.2(b) 
Heads, area of, to be stayed, HG-345.1(c), Fig. HG-345.1, 
HG-345.2, HG-345.3 
blank {see Heads, flat) 
concave and convex, HG-305, HG-305.1, HG-305.8, 

HG-309.1, HW-715, HC-310.1, HC-310.2 
cone {see Heads, conical) 
conical, HG-305.1 
dished {see Covers) 
ellipsoidal {see Heads, formed) 
flanged, HG-307.4, Fig. HG-307, HG-345.2, Fig. HG-345.2, 

HW-711.1, HLW-41 1.2 
flanged-in openings {see Heads, formed) 
flat, acceptable types of, HG-307, Fig. HG-307 
area to be stayed in, HG-345.1, Fig. HG-345.1 
circular, HG-307.2, HG-325 
noncircular, HG-307.3, HG-325 
openings in, HG-325 
reinforcement requirements, HG-325 
unstayed, HG-307, HLW-305 
flat spots on formed, HG-305. 9 
formed, attachment by welding, HW-712, HW-715 
built up of several shapes, HG-305. 7 
concave to pressure, HG-305, HG-309.1, HW-715, 

HC-310.1 
convex to pressure, HG-306, HW-715, HC-310.2 
dished (bolted) {see Covers) 

ellipsoidal, HG-305.1, HG-305.2, HG-305.9, HG-323.1, 
HG-323.2, HW-715, HW-715(a), HW-715(b), 
HLW-305. 2 
flanged-in openings, HG-323, HG-345.2 
hemispherical, HG-305.1, HG-305.4, HG-305.9, 
HG-323.1, HG-323.2, HW-715, HW-715(c), 
HW-8 12(b), HLW-305.5, HLW-306.2 
manholes in, HG-323.2 
openings in, HG-320, HG-321, HC-315 

reinforcement for, HG-320.3(a), HG-321 
pressure, maximum allowable working, HG-305. 2- 

HG-305.4 
skirts, length of, HG-305.8, HW-715 
stayed as flat surfaces, HG-305, HG-345 



237 



2007 SECTION IV 



staying of, HG-305.5, HG-345 

torispherical, HG-305.1, HG-305.3, HG-305.5, HG-305.6, 
HG-305.9, HG-323.1, HG-323.2, HG-345, 
HW-715(a), HW-715(b), HLW-305.3 
unstayed, HG-305.6, HLW-305.4, HLW-306.1 
integral, HG-307.4, Fig. HG-307, HC-310.1 
noncircular, HG-307.4, Fig. HG-307 
nonstandard pressure parts, HF-203.2 
openings in {see Heads, formed) 
segments of areas to be stayed, HG-345. 2, Fig. HG-345. 2, 

HG-345. 3 
skirts, length of {see Heads, formed) 
stamping of, HG-530.2(a) {see also Boilers, stamping) 
staying of {see Heads, formed) 

thickness of, HG-305, HG-307, Fig. HG-307, HG-309, 
HF-301.1, HF-301.2, Tables HF-301.1, HF-301.2, 
HW-703, HB-1302, HC-310, HC-311 
unflanged, HG-345.1, Fig. HG-345. 1, HG-345.3, HW-711.2 
unstayed, HG-305.6, HG-307, Fig. HG-307, HG-345. 1(b) 
Head-to-shell attachments, HLW-415 
Heat, direct radiant, on staybolt nuts, HG-341.3 
Heaters, oil, HG-707 

Heat exchangers, safety and safety relief valves, HG-400.3 
Heat generating apparatus, field wiring for, HG-631, HG-634 
oil and gas-fired, and electrically heated boilers, safety 

equipment for, HG-640(a) 
symbol of certifying organization affixed to, HG-640(b), 

HLW-602.3 
water heaters, HLW-602.3 
Heating, space, HG-400.3(b) 
Heating boilers, HG-100, HC-100 
Heating surfaces, HG-403 

of boilers, for determining safety valve capacities, HG-400. 1 
Heating systems, hot water, HG-709 
closed, HG-709.2, HG-709.3 
forced, Table HG-709.2 
gravity, Table HG-709. 1 
open expansion tank, HG-709. 1 
steam, HG-703.2 
Heating values of fuel, HG-512(b), B-100, B-102 
Heat or heat treatment lots, HF-205.2(b)(c), HF-205.3 
Heats of combustion of fuels, B-102 
Heat treatment of material submitted for Code approval, 

A-101, A-103, A-105(d) 
High-limit pressure-actuated combustion controls {see 

Controls) 
Holes, drain, in safety valves, HG-400. 1(a) 

drilled bolt, in flanged connections, HG-309. 1, HG-370.2, 

HC-311. 1 
drilled in corrugated or ribbed furnaces, HG-3 12.6(c) 
drilled or punched tube, HG-360.1 
elliptical (Footnote 5), HG-320.1 

flanged, in boilers, for direct attachment of safety or safety 
relief valves, HG-70 1.1 



outwardly, HB- 1307(a) 
for nozzles and nozzle fittings, HW-731.3, HB- 1306(a), 

HB- 1307(b) 
for pipe connections in brazed boilers, HB- 1306(b) 
handholes {see Handholes) 
in welded joints, HW-720 
ligament efficiency of, HG-350 
multiple, reinforcement for, HG-328 
obround (Footnote 6), HG-320.1 
punched tube, HG-360.1 
reinforcement of {see Reinforcements) 
screw or threaded {see Holes, threaded) 
shape of, in boilers or formed heads, HG-320 
spacing of, HG-350.4, Fig. HG-350. l-HG-350.3 
strength and design of finished, HG-320.3 
tapped, for attachment of safety valves, HG-70 1.1 
for attachment of water gage glasses, HG-606(b) 
for threaded connections to boilers, HG-370.1 
telltale, HG-341.1, HW-730.3 
threaded (screwed), HG-305. 5(c), HG-340.2, HG-341.1, 

HG-370, HG-370.1, HG-701.3 
tube {see Tube holes) 

with removable covers in boiler jackets, HG-530.2 {see also 
Openings) 
Horizontal firetube boilers, HG-343.2, HG-345. 1(c), 

HG-604(b) 
Horizontal return tubular boilers, HG-330.2, HG-725, 

HW-711.1 
Horizontal tubular flue type boilers, HG-530.2 
Hot leg, in control circuitry, HG-632(b)(2) 
Hot water boilers {see Heating boilers; Hot water systems) 
Hot water heaters, installation requirements of, HG-700 {see 

also Heating boilers; Hot water systems) 
Hot water supply, heated by high temperature water, 
HG-400. 3(b) 
heated indirectly by steam coils or pipes, HG-400. 3(a) 
Hot water supply boilers, outside Code jurisdiction, HG-101.2 
Hot water systems, closed type expansion tanks, HG-709.2 
minimum capacity, HG-709.3, Tables HG-709. 1, HG-709.2 
expansion, thermal, provisions for, HG-709 
fluid relief columns, HG-709 
hot water tanks, HG-709 

open type expansion tanks, HG-709. 1 {see also Heating 
boilers) 
Hydrostatic tests, bursting, for cast iron boilers or boiler parts, 
HG-501.1, HC-400, HC-401, HC-402 
rating of boilers based on, HC-404 
test gages for, HC-402. 1 

for wrought boilers, HG-501.1, HG-502.3 
witnessing, recording, and certifying, HC-403 
of all completed boilers, welded or brazed, HG-510 
of all completed cast iron boilers, HC-410 
of all completed water heaters, HLW-505 
proof, of wrought boiler parts, HG-501-HG-506 



238 



2007 SECTION IV 



test gages for, HG-505, HLW-502.2 (see also Gages) 
types of, HG-501.1 

Identification markings, arrangement of, HG-530, HG-531, 
HG-533.5, Figs. HG-530.2, HG-530.3, Forms H-2-H-5 

for material, HF-210 

for nonidentified material, HG-200.7, HF-202(b), 
HF-203.1(b), HF-205.3 

for nonstandard pressure parts, HF-203.3(a) 

for safety and safety relief valves, HG-402. 1 

for shutdown switches and circuit breakers, HG-634 

for standard pressure parts, HF-203.1, HF-203.3 

for stop valves, HG-710.5 

for welded standard pressure parts, HF-203.3(a) 
Identifying marks, for brazers or brazing operators, HB- 1202.4 

for welders or welding operators, HW-613 
Increments of pressure applied in hydrostatic proof tests, 

HG-501.4, HG-502.1, HG-502.2, HG-502.4 
Indicating gages, attached to test pressure parts, HG-505, 

HC-402.1 (see also Gages; Test gages) 
Indicating pressure gages (see Gages) 
Indoor overflow of open expansion tank systems, HG-709.1 
Induction brazing process, HB-1200, HB-1202.2 
Inertia, moment of, for circumferential stiffening, HG-312.5 
Inlet area of safety valves, HG-70 1.2(b) 
Inlet connections for safety valves, HG-70 1.2(a) 
Inlet openings, of safety valves, HG-400.1(c) 

of safety-relief valves, HG-400.2(d) 
Inlet valves, in water feeding devices, HG-606(a) 
Input, heat, of boilers, HG- 101. 2(a), HG-400.2(d) 
Insertion of stays in holes to be welded, HW-710.1 (see also 

Stays; Welded stays) 
Inside nuts, for attachment of through-stays to, HG-305.5(c) 
Inspection, dye penetrant, HB-1503 

not required for standard pressure parts, HF-203.1, HF-203.3 

of boiler parts, HG-515 

of boiler parts requiring Partial Data Reports, HG-520.2 

of brazing procedures, HB-1500, HB-1501 

of cast iron boilers or boiler parts, HC-410, HC-501 

of critical openings, HG-320.2(c) 

of field assembled boilers and parts, HG-533, HG-533.3, 
HG-533.4, HG-533.6 

of hot water heaters, HLW-600 

of prefabricated or preformed pressure parts, HF-203 

of proof tests, HG-506 

of welded boilers or other parts during fabrication, HW-900 

of welder and welding operator performance qualifications, 
HW-911 

of welding procedure qualifications, HW-910 

openings, HG-330, HG-330.1, HG-330.4, HG-705, HG-720 

visual, HW-731.2, HW-731.3, HB-1304, HB-1503 (see also 
Visual examination) 
Inspectors, authorized, HG-515.2, HG-515.3, HG-533.3, 
HG-533.4, HG-533.6, HLW-600. 1 



Inspector's duties, HG-515.4, HLW-600.3 
Inspector's responsibilities, HG-501.5, HG-515.3, HG-520.2, 
HG-533.1, HG-532.2, HG-532.3, HG-533.3, HG-533.4, 
HG-533.6, HF-203.1, HF-205.1-HF-205.3, HF-210, 
HW-900, HW-910, HW-911, HB-1202.4, HB-1501, 
HB-1502 
Installation requirements, boilers, HG-700 

bottom blowoff or drain valves, HG-715, Table HG-715 

feedwater connections, HG-705 

hot water heaters, HG-700, HLW-800 

oil heaters, HG-707 

piping, HG-703 

safety and safety relief valves, HG-70 1, HLW-800. 1 

settings, HG-720 

stop valves, HG-710 

supports, HG-725 
Instruments, for hot water boilers, HG-610 

pressure or altitude gages, HG-611 (see also Gages) 

thermometers, HG-612 

for steam boilers, steam gages, HG-601 (see also Gages) 
water gage glasses, HG-602 (see also Water gage glasses) 
Insulating rings, HG-200.7 
Integral cast iron bolted flanges, HC-310.1 
Integral flanges on nozzle fittings, HB- 1307(b) 
Integral forged circular and noncircular heads, HG-307.4 
Integral reinforcement, areas, HG-327.2(2) 

nozzles with, HG-327.1, HW-731.5 
Interchange of qualifying tests, HW-612 
Internal cross-sectional areas of discharge pipes, HG-70 1.6 
Internally fired boilers, furnace access doors for, HG-330. 1(c) 
Internally threaded fittings, attached by welding, HW-731.6 
Internal parts, subject to deterioration, HG-200.2 
Internal pipes, in boilers, connections to, HG-70 1.4 
Internal pressure, HG-301, HG-321.2, HG-502.1 -HG-502.4, 

HF-203 (see also Pressure) 
Internal volume, of cast iron boilers, HC-325 

of vertical firetube boilers, HG-330.4(c) 
Inwardly extending nozzles, HG-326.4(c) 
Inwardly flanged heads or tubesheets, HW-711.1 
Iron, and steel bodied valves, HG-400.1(a) 

cast (see Cast iron) 

wrought (see Wrought iron) 
Isolation transformers, HG-632 

Jackets, boiler, HG-530.4, HG-621 

Jacks, HW-8 10(b) 

Joints, blind (see Joints, brazed) 

bolted, cast iron, circular, HC-310.1, HC-311, Fig. HC-311 
circular and noncircular, HG-307.2-HG-307.4, 

Fig. HG-307 
flanged connections for external piping, HG-370.2 
nozzle fittings, HB- 1307(b) 
spherically dished covers with flanges, 
HG-309,Fig. HG-309 



239 



2007 SECTION IV 



brazed, applying filler metal to, HB-1304 
cleaning of, HB-1400-HB-1402 
clearances, HB-1305, Table HB-1305 
combination of dissimilar materials in, HB-1101 
connections, HB-1307 
defective, HB-1402, HB-1501, HB-1503 
dip brazing of, HB-1200 
efficiency factors of, HB-1301, HB-1304 
face-feeding of, HB- 1304(a) 
filler metals for, HB-1102, HB-1304 
fluxes and atmospheres for, HB-1103 
flux residue removal from, HB-1401, HB-1503(a) 
inspection, HB-1501-HB-1503 
lap, HB- 1202. 1(b), HB- 1300(b) 
materials for, HB-1100-HB-1103 
metals, base, HB-1300, HB-1400 
repair of, HB-1402, HB-1503 
socket type, HB- 1304(a) 
strength of, HB-1300 

temperature, permissible service, HB-1303 
visual examination of, HB-1503 
butt welded, circumferential butt, HW-701.1, HW-812, 
HLW-401.1 {see also Welded joints) 
double welded butt, HW-701.1, HW-820.1, HLW-401.1 

{see also Welded joints) 
electric resistance, carbon steel pipes and tubes, 

Table HF-300.1 
head-to-shell attachments, HW-715 
longitudinal, HW-701.1 {see also Welded joints) 
openings in, HG-321, HW-720 
steel pipes and tubes, Table HF-300.1 
wrought iron, pipes and tubes, Table HF-300.1 {see also 
Welded joints) 
corner, welded, HG-340.5, Fig. HG-340.3, HG-345.1, 

HW-701.3, Fig. HW-701.3, HLW-401.2 
double full fillet lap welded, HW-702(d) 
efficiencies {see Joints, brazed; Welded joints) 
fillet welded, HG-307.4, Fig. HG-307, HG-725.6, 
HW-701.2, HW-701.3, HW-710.4, HW-711.1, 
HW-712.1, HW-730.1, HW-730.2, HW-731.4- 
HW-731.7 
full penetration welded, HG-312.4, HG-312.7, HW-701.3, 
Fig. HW-701.3, HW-711.2, HW-712.2, HW-731. 1- 
HW-731.6, Fig. HW-731 
fusion welded, HG-307.4, HG-312.6, HG-725.6, HW-701.1 
gasketed, HG-307. 2 (footnote) 
groove welded, HW-730.1, HW-730.2, HW-731. 7, 

Fig. HW-731 
lap welded, HW-701.2 
longitudinal butt welded, HG-312.6, HW-701.1, HW-800, 

HW-812, HLW-401.1 
partial penetration welded, HW-731. 3, HW-731. 6, 

Fig. HW-731 
single-bevel welded, HW-731. 4, HW-731. 5, Fig. HW-731 



single full fillet welded, HW-701.3 

single-J welded, HW-731. 3, HW-731. 4, HW-731. 5, 

Fig. HW-731 
socket type {see Joints, brazed) 
strain absorbing, in piping, HG-703.1, Figs. HG-703.1, 

HG-703.2 
swing, HG-703.1, Figs. HG-703.1, HG-703.2 
tee, HW-701.3, HLW-401.2 
threaded, HG-307.4, Fig. HG-307, HG-320.3(c), HG-341.1- 

HG-341.3, HG-370.1, HG-701.3 
welded, efficiencies (efficiency factors), HW-702 
pipe connections, in brazed boilers, HB- 1306(b) 
preparation, HW-801 
repair of defective, HW-830 
requirements for, HW-700, HW-701, HW-820 
single-welded butt {see Welded joints) 
single-welded lap {see Welded joints) 
weld metal, stress values of, HW-730.2 {see also Welded 
joints) 
Jurisdiction, outside of Code, HG-101.2 

Knuckles radius, HG-305.6 

Lap joints, welded, HW-701.2 {see also Joints, lap) 
Lap welded pipe and tubes, Table HF-300.1 
Leeds suspension bulb type furnaces, HG-312.6 
Lever handles for cocks, HG-602(a), HG-611 
Licenses, patented materials, A- 104 
Lifting levers on safety valves, HG-402.1 
Lift pressure of safety valves, HG-402.3(a) 
Ligaments and ligament efficiencies, HG-350 
Limit controls, electrical, HG-633, HLW-702 
Limits, Code service for boilers, HG-101 

of metal available for reinforcing, HG-326 

of reinforcement for multiple openings, HG-328.1 
Lined potable water heaters 

controls, HLW-700 

design of weldments, HLW-400 

general material requirements, HLW-200 

inspection and stamping, HLW-600 

installation requirements, HLW-800 

pressure relieving devices, HLW-300 
Loading, plane of greatest, HG-321.1 

types of, HG-501(a) 
Loads, bolt, HG-307.2(b) 

carried by welds, D-100, D-101 

on hangers, HG-725.1 

on stays, HG-340, HG-340.4, HG-342.1, HG-342.2 

radial membrane, HG-309, HG-309.1 
Locking arrangement, mechanical, HG-307.4, Fig. HG-307 
Locomotive type boilers, HG-330.4, HG-530.2 
Longitudinal axis of boilers, HG-350.4 
Longitudinal center line of diagonal stays, HW-7 10.4(c) 
Longitudinal joints {see Welded joints) 



240 



2007 SECTION IV 



Longitudinal pitch of openings, HG-350.1(a) 
Low-alloy steel, Table HF-300.1 
Lowest permissible water level, HG-603(b), HG-614(b) 
Low-water fuel cutoff, HG-604(a), HG-606, HG-614 
Lugs, HG-725.6, HC-320 

Machining, for joint preparation, HW-801 

of test bars, HC-402 
Mains, steam and hot water boiler, HG-703.1, Fig. HG-703.1 
Manholes, HG-323.5, HG-330.1-HG-330.3, HG-345.1(g), 

HF-203.1 
Manual application of brazing filler metal, HB- 1304(a) 
Manually operated shutdown switches, HG-634 
Manual welding, HW-701 

Manufacturer's, Data Report (see Manufacturer's, master Data 
Reports) 
design or type numbers, HG-402.1(b) 
identification marks (marking) (see Identification markings; 

Markings; Stamping) 
master Data Reports, HG-520, HG-520.1, HG-532.1, 
HG-532.2, HG-533.2, HG-533.3, HC-403, Forms 
H-2-H-5 
nameplates, HG-530.2 
names, HG-402.1(a), HG-531, HG-533.4, HF-203.1, 

HF-203.2 
Partial Data Reports, HG-520.2, HF-203.1, Form H-4 
reports on tests of nonidentified materials, HF-205.3 (see 

also Tests) 
serial numbers, on all boilers, HG-530.1(a) 

on boiler parts and accessories, HG-531 (a) 
stamping, of boiler, HG-530 (see also Identification 

symbols; Identification markings; Stamping) 
trademarks, HG-402.1(a), HF-203.1-HG-203.3 
Manufacturer's (or contractor's) responsibilities for brazing, 
HB-1001 
certifying others' work, HG-515 
compliance with Code, HG-515 
conducting qualifying tests, HW-401, HB-1001 
establishing fabrication procedures, HW-401, HB-1001 
executing Data Reports, HG-520, HG-532.1, HG-532.2, 

HG-533.2, HG-533.3, HC-403 
inspecting and certifying, HG-515.3 
providing design details, Preamble 
quality control, HC-501 

recording test results, HW-613, HB- 1202.4, HC-403 
submitting parts for inspection, HW-900 
testing safety and safety relief valves, HG-402.3 
welding, HW-401 
Markings, arrangement of, HG-530.2 

transfer of, HF-210 (see also Identification markings; 
Stamping) 
Master gages, HG-505(c), HC-402. 1(c) 
Materials, acceptable for fusion welding, HW-500 
approval of new, HG-200.3, A-100-A-105 



bolting, Table HF-300.1 
chemical composition, HC-202 
combination, of different specifications of, joined by 
welding, HW-501 
of dissimilar, joined by brazing, HB-1101 
duplicate parts of same, HG-504 
ferrous, maximum allowable stress values, HF-300, 

Table HF-300.1 
specifications, HF-200, HF-201, Table HF-300.1 
tensile strength, Table HF-300.1 
for brazing, HB- 11 00 

for cast iron boilers, HC-200, Table HC-300 
for filler metals, HW-500, HB-1102 
for lined potable water heaters, HLW-200 
for welding, HW-500 
general requirements, HG-200, HF-200, HW-500, HB-1100, 

HC-200 
identification, HF-210 

maximum allowable stress values, cast iron, HC-300, 
Table HC-300 
ferrous, HF-300, Table HF-300.1 

nonferrous, HF-300, Table HF-300.2, HB-1100 (see also 
Stress values) 
metallic enclosures, control circuitry, HG-632 
metals (see Filler metals; Metals; Weld metal) 
nonferrous, nameplates, HG-530. 1; HG-530.2; 

Figs. HG-530. l-HG-530.3, HG-530.6, HG-530.7 
pipes and tubes, HG-602(a); HG-603(a); HG-604(a); 
HG-605(c); HG-611(a), (c); HF-204; HF-204.1 
plates, HF-301.2, Table HF-301.2 
specifications of, Table HF-300.2 
stress values, maximum allowable, HF-300, 

Table HF-300.2 
tensile strength, Table HF-300.2 
nonidentified (see Materials, not identified) 
nonpressure part, HG-200.7, HLW-205 
nonstandard pressure parts, HF-203.2 
not found in Section II, HG-200.3 
not fully identified, HF-205 

not identified by mill test reports, HF-203.1, HF-203.3 
of bars, HF-202; Tables HF-300.1, HF-300.2 
of rods, HG-202; Tables HF-300.1, HF-300.2 
of shapes, HF-202; Tables HF-300.1, HF-300.2 
of small parts of unidentified, HF-203.1(b), HW-502 
of standard pressure parts, HF-203.1 (a), HF-203.3 
of stays and staybolts, HF-202(a); Tables HF-300.1, 

HF-300.2 
of weldable quality, for nonpressure parts, HG-200.7, 

HLW-205 
plate, for pressure-containing parts, HF-201; HF-203; 

HF-205; Tables HF-300.1, HF-300.2 
prefabricated or preformed pressure parts, HF-203 



241 



2007 SECTION IV 



specifications for, HF-200-HF-206; HF-210; 

Tables HF-300.1, HF-300.2; HW-500; HB-1100; 
HB-1102; HC-200 
specific requirements for, HG-201, HF-201-HF-204 
subject to deterioration, HG-200.2 
suitable for welding, cold bending, close coiling, 

HF-205.2(b) 
test bars, cast iron, HC-205, HC-206, HC-207 
tests, transverse, cast iron, HC-209 

yield and tensile, HG-501.6, HC-203, HC-204, HC-208 
thickness, exceeding specification limits, HG-200.6 
gasket, HG-330.3(d) 

minimum, HF-301.1; HF-301.2; Tables HF-301.1, 
HF-301.2; HW-703 
transparent, for water gages, HG-603(b) (Note) 
unidentified, HG-200.3, HF-202(b), HF-205, HF-205. 1- 

HF-205.3 
use, not limited by production methods, HG-200.5 
not limited by specification title, HG-200.4 
Maximum allowable stress values {see Stress values) 
Maximum allowable working pressures {see Working 

pressures) 
Maximum pitch of stays, HG-340.1, HG-340.3 
Maximum thicknesses of materials {see Materials) 
Mechanical locking arrangements, HG-307.4, Fig. HG-307 
Membrane loads, HG-309, HC-311.1 
Membrane stresses, HG-501.5 (Note) 
Metals, base, preparation for welding, HW-801 

filler, brazing, HB-1102, HB-1300, HB-1301, HB-1303- 
HB-1305, HB-1402, HB-1503 
weld, HW-701.1 
weld, as reinforcement, HG-327.1 
in butt joints, HW-701.1, HW-820.1 
specifications of, HW-500 
stress values for, HW-730.2 
Methods, of calculating ring reinforced furnaces, C-100, C-101 
of checking capacity of safety valves, B-100-B-102 
of computing openings in shells, D-100, D-101 
of determining capacity of safety valves, HG-402.3 
of determining net area, irregular segments of heads, 
Fig. HG-345.2 
Mill test reports, HG-200.7, HF-203 
Modular steam heating boilers, HG-607 
Moment, arm, HG-307. 1 
edge, HG-307.2, HG-307.3 
of inertia, HG-312.4(i), HG-312.5 
total, HG-309, HC-311, Fig. HC-311 
Morison type furnaces, HG-312.6 
Mounting, safety and safety relief valves, HG-701 {see also 

Safety and safety relief valves) 
Multiple boiler installation, HG-605(b); HG-613(b); 

Figs. HG-703.1(a), HG-703.1(b), HG-703.2; HG-710.3 
Multiple duplicate construction, HG-515.4(b) 
Multiple openings, reinforcement for, HG-328 



Nameplates, manufacturer's, HG-402.1, HG-530.2, HB-1510 

{see also Identification markings) 
Names, manufacturer's {see Identification markings) 
Necks, extended integrally as reinforcement, HW-731.5 
New materials, approval of, HG-200.3 
Nipples, short, HG-606, HG-701.1 
Nominal head thicknesses, HW-715 
Noncircular flat heads, covers, and flanges, HG-307 
Nonferrous fittings, HG-606(b) 
Nonferrous materials {see Materials) 
Nonferrous tubes, thickness, HLW-307.2 
Nonpressure parts, welded to pressure parts, HW-610 
Nonstandard pressure parts, HF-203. 2 
Not fully identified materials {see Materials) 
Not identified materials {see Materials) 
Nozzles, Fig. HG-326.2, HG-326.4(c), HG-237.1, HF-203, 
HW-730, HW-731, Fig. HW-731, HB- 1307(b), 
HC-315(b), HC-320, HLW-431.2-HLW-431.6, D-101, 
Fig. D-101 
Numbers, manufacturer's, design or type, HG-402.1(b) 
material serial S, HF-205. 3 
serial, HG-530. 1(a)(5); Figs. HG-530.2, HG-530.3 
of threads for staybolts to extend 
beyond plate, HG-341.1 
of pipe connections, curved surface, HG-370. 1 
part manufacturer's serial, HG-531 
specification, HF-205. 3 
Nuts, staybolts fitted with, HG-341.3 
through-stays with, HG-305.5(c), Fig. HG-340.2 

Obround flat heads, covers and blind flanges, HG-307.3 
Obround shaped openings, HG-320.1, HG-327.2 
Offset of plate edges at butt joints, HW-812 
OG rings, flared or welded, HG-3 12.4(g) 
Oil fired boilers, HG-640, B-101 
Oil heaters, HG-707 
Open expansion tanks, HG-709.1 

Opening test of pressure-temperature relief valves, HG-402.5 
Openings and reinforcements, HG-320-HG-328, HC-315, 
HLW-308 
feedwater, HG-705 
fire door, HG-330.5 
flanged, in boilers, for valve connections, HG-701.1 

outwardly, HB- 1307(a) 
flanged-in, HG-323 {see also Heads, formed) 
for gravity drains, HG-715(c), HG-716 
for inlet safety and safety relief, HG-400.1(b), HG-401 
for outlet connections, water column, HG-604 
for outlet piping, HG-400.1(f); Figs. HG-703.1(a), 

HG-703.1(b), HG-703.2 
for pipe connections, HG-701; Figs. HG-703.1(a), 

HG-703.1(b), HG-703.2; HG-703.2; HG-705; HG-715; 
HB-1306, HB-1307 
frames for reinforced, HF-202(a) 



242 



2007 SECTION IV 



handholes {see Handholes; Openings, inspection and access) 

in drain valves, water gage glass, HG-603(a) 

in furnace sheets, HG-312.6 

in heads, HG-320.1, HG-320.3, HG-321, HG-323, HG-325, 

HG-328.2, HG-330.4(b) 
in shells, examples of computation of, D-100, D-101 
inspection and access, HG-330 

multiple, HG-350.1-HG-350.4, Figs. HG-350.1-HG-350.4 
reinforcement of circular and elliptical, HG-321 
inspection and access, HG-330, HG-330.5, HG-705, HG-720 
in welds, HW-720, HLW-420 
larger than covered by rules, HG-320.2(c) 
manholes {see Manholes) 

multiple, HG-328, HG-350.1-HG-350.4 {see also Holes) 
nozzle, HW-731, HW-731.2-HW-731.5, Fig. HW-731, 

HB-1306, HB-1307 
parallel to shell axis, HG-350.2 
reinforcement requirements for, HG-320, HG-321, HG-323, 

HG-325-HG-328, HLW-308 
screwed (threaded) {see Openings, threaded) 
shape of, HG-320.1, HG-327.2 
size of, HG-320.2 
spacing of, HG-350.1-HG-350.4, Figs. HG-350.1- 

HG-350.4 {see also Holes) 
strength, and design of finished, HG-320.3 

of welded, HW-730.1 
tapped, HG-370.1, Table HG-370, HG-606, HG-701.1 
threaded, HG-320.3, HG-370.1, HG-701.3 
transverse to shell axis, HG-350.3 
unreinforced, HG-320.2, HG-320.3 
vent, in open expansion tanks, HG-709.1 
washouts, HG-330. 1(a), HG-330.4, HC-325 {see also 
Openings, inspection and access) {see also Heads; 
Holes; Reinforcements) 
Operation of boilers, Preamble, HG-101, HG-300(c) {see also 

Boilers, service) 
Operators, brazing, identifying symbols, HB- 1202.4 
qualification of, HB-1001, HB- 1202.2, HB- 1202.3 
Operators, welding, identifying symbols, HW-613 

qualification of, HW-401, HW-610-HW-612 
Orifice sizes, safety and safety-relief valves, HG-402.3(b) 
Outlet, connections, HG-604 

piping, HG-400. 1 , HG-70 1.1 
Outside-screw-and-yoke stop valves, HG-710.4 
Outside suspension-type boiler setting, HG-725.1-HG-725.4 
Outwardly extending nozzles, HG-326.4(c) 
Outwardly flanged heads or tubesheets, HW-711.1 
Oxyacetylene welding process, HW-600(a)(b) {see also 

Welding) 
Oxygen cutting, HG-501.6 
Oxyhydrogen welding process, HW-600(a) 

P-numbers, for welding materials, HW-500 
Pad reinforced openings, D-100, Fig. D-100 



Pads, reinforcement, HG-327.1, HG-327.2 

saddle type, as integral nozzle reinforcement, HW-731. 5 
Pad-to-nozzle attachment weld metal, HG-327. 1 
Partial Data Reports, HG-520.2, HF-203, HF-203.1 {see also 

Data Reports; Manufacturer's Data Reports) 
Parts, cast, HF-203.2; Tables HF-300.1, HF-300.2; HC-200 

cylindrical, openings in, HG-350.1 
under external pressure, HG-312 

designed for external pressure, HF-203.1, HF-203.2 

die formed, HF-203.1, HF-203.2 

duplicate, tests of, HG-504 

forged, HF-203.1, HF-203.2 

internal, subject to deterioration, HG-200.2 

material for {see Materials) 

nonpressure, HG-200.7 

prefabricated or preformed, HF-203 

pressure, containing, HF-201 
nonstandard, HF-203.2 
standard, HF-203.1, HF-203.2 

rolled, HF-203.1, HF-203.2 

small, HF-203. 1(b), HW-502 

strength of, not computable, Preamble 

subject to collapse, HG-503 

tests of {see Tests) 

welded, nonpressure, HG-200.7, HF-202(b) 
standard pressure, HF-203. 3 
Penetration, of brazing filler metal, HB-1301, HB-1304, 
HB-1503 

welds, into base metal, HW-701, HW-820 {see also Welded 
joints) 
Personnel, safety of, HG-501.3, HG-701.6(b) 
Pinholes, in brazed joints, HB-1503 {see also Joints, brazed) 

in welded joints, HW-830 {see also Holes; Welded joints) 
Pipe,piping and pipe connections, 

altitude gage, HG-611 

blowoff, HG-715 

brazed, HB-1306, HB-1307 

coils, HG-400.3, HF-203.2 

couplings, HB- 1306(b) 

discharge, pump, Figs. HG-703.1, HG-705 

discharge, safety valve, HG-70 1.6 

drain, HG-715 

expansion and contraction, HG-703.1, Figs. HG-703.1, 
HG-703.2 

external, HG-370, Table HG-370 

feedwater, HG-604, HG-705 

ferrous, HG-602, HG-604, HG-605 

fittings, HG-603, HG-605, HG-606, HG-701, HG-703 

flanged, HG-370.2 

low-water fuel cutoff, HG-606 

nonferrous, HG-611 

nozzles, D-101, Fig. D-101 

pressure gage, HG-611 

return, HG-703.2, Figs. HG-703.1, HG-703.2 



243 



2007 SECTION IV 



safety and safety relief valve, HG-701 

steam gage, HG-602 

steel {see Steel) 

supply, HG-710, Figs. HG-703.1, HG-703.2 

threads, HG-370.1, Table HG-370 

used as tubes, HG-301 (Note) 

water column, HG-604 

water gage glass, HG-603 

waterlevel control, HG-604 

wrought iron {see Iron) 
Pitch, of openings, HG-350.1, HG-350.2 

of stays and staybolts, HG-340, HG-340.1, HG-340.3, 
HG-340.5, Fig. HG-340.1, Table HG-340 
Plain sections, combination type furnaces, HG-312.7 
Plastics, water absorption of, Appendix I 
Plate, ends, forming of, HW-800 

for pressure containing parts, HF-201 

not fully identified, HF-205 

specifications, HF-201, Table HF-300.1, HF-300.2 
Plates, alignment of edges, HW-810, HW-820 

beveling {see Welding) 

connected by stays, HG-340. 1(a) 

cover, HG-307.1, HF-203.2 

cutting, HG-501.6, HW-500(a), HW-801 

ends, forming of, HW-800 

ferrous, HF-301.1, Tables HF-300.1, HF-301.1 

flat stayed, HG-340, HW-701.2 

identification of {see Identification markings) 

nonferrous, HF-301.2, Tables HF-300.2, HF-301.2 

preparation of, HW-801 

reinforcement, HW-730.3, HW-731.4 

shell, HF-301.1, Table HF-301.1, HF-301.2, Table HF-301.2 

steel {see Steel plate) 

thickness {see Plates, shell) 
Plug cocks, HG-710.4 
Plugs, threaded, HG-3 12.6(c) 

washout, HG-330.1, HG-330.4, HG-325 
Postbrazing operations, HB-1401 
Postwelding operations, HW-8 10(c) 
Preamble 
Prefabricated and preformed pressure parts, HG-203 {see also 

Parts) 
Pressure, application of {see Tests) 

atmospheric, HG-300(c) 

blowdown, safety valve, HG-402.3(a) 

controls {see Controls) 

design, HG-300(a) 

external, HG-3 12, HG-503, HW-702.1, A- 101(b) 

forming of plate ends, HW-800 

gage, HG-300(c) 

gages {see Gages) 

internal, HG-301, HG-321.2 

lift, safety valve, HG-402.3(a) 

parts, nonstandard {see Parts) 



standard {see Parts) 

popping, safety valve, HG-402.3(a) 

relieving devices, HG-400 

relieving valve requirements, HG-400 

setting, tolerances for, safety and safety relief valves, 
HG-401 

stress, materials object to, HG-200.1 

temperature relief valves, HG-400.2, HG-402.5 

temperature relief valve tests {see Tests) 

tests, hydrostatic {see Hydrostatic tests) 

welding processes, HW-600 
Procedures, brazing {see Qualification) 

for tests {see Tests) 

welding {see Qualification) 
Processes, brazing, HB-1200 

welding, HW-600 
Production, method of, material not limited by, HG-200.5 

ratings of boilers, based on tests, HC-404 

work, HW-6 11, HB- 1202.3 
Proof tests, HG-500, HLW-502 {see also Tests) 
Pump discharge.piping, Figs. HG-703.1, HG-703.2 
Pumps, casing of, HF-203.1 
Purves type furnaces, HG-3 12.6 

Qualification, brazing operators, HB-1001, HB-1202.2 

brazing procedures, HB-1001, HB-1100-HB-1103, 
HB-1202, HG-1305 

requalification, HB-1305(b) 

welding operator, HW-401, HW-610, HW-612, HW-711, 
HW-713, HLW-450 

welding procedure, HW-401, HW-600, HW-610, HW-611, 
HW-613, HLW-450, HLW-460 
Quality, structural, rods, bars, shapes, HF-202(b) 

weldable, HF-202(b), HF-202.3(c), HW-502 
Quality control of castings, HC-501 
Quality control, outhne of features, HC-502, F-202 
Quality control system, Appendix F 
Quality factors, ferrous castings, Table HF-300.1 [Note (5)] 

nonferrous castings, Table HF-300.2 [Note(4)] 

Radial deformation, threaded joint, HG-307.4 
Radii, inside, HG-301, HG-305.1 

corner, HG-307.1, HG-307.4 

crown, HG-305.1, HG-305.6, HG-309 

knuckle, HG-305.6, HG-309, HC-311 

spherical, HG-305.1, HG-309 
values of factor K u Table HG-321 

of fillets and transition sections, HC-320 
Ratings, of boilers, based on tests, HC-404 
Recessing, holes for nozzles, HW-73 1.2(b) 

tube holes, HW-713 
Records, of brazer and brazing operator 

identifying marks, HB- 1202.4 

of brazer and brazing operator 



244 



2007 SECTION IV 



qualification tests, HB- 1202.4 

of brazing procedure qualification tests, HB-1201 

of capacity tests of relieving devices, HG-402.8 

of tests of associated test bars, HC-402 

of tests of unidentified materials, HF-205.1, HF-205.3 

of tests to establish maximum allowable working pressure, 
HC-403 

of welder and welding operator identifying marks, HW-613, 
HLW-453 

of welder and welding operator qualification tests, HW-613, 
HLW-453 

of welding procedure qualification tests, HW-613, HLW-453 
Rectangular flat heads, HG-307.3 
Reexamination of repaired welded joints, HW-830 
Refractory materials, protecting furnace extensions, HW-712 
Regulators, damper, HG-604 

feedwater, HG-604 
Reinforced openings, for pipe connections, HW-731.1, 
HW-731.6 

frames for, HF-202(a) 

in flat heads, HG-325 

in formed (dished) heads, HG-321, HG-323 

in shells, HG-321, Table HG-321 

in welds, HW-720 {see also Heads; Openings) 
Reinforcements, area of, HG-321, D-100, D-101 

configurations, representative, Fig. HG-326 

integral, HW-731.5, HC-315 

metal available for, HG-326 

of butt welds, HW-701.1 

of multiple openings, HG-328 

pad, HW-731.5, D-100 

plates, HW-730.3 

provisions of, HG-321.1 

saddles, HW-730.3 

strength of, HG-327 {see also Openings) 
Rejection of brazed joints, HB-1503 
Repair, of brazed joints, HB-1503 

of welded joints, HW-830 
Reports, Master and Partial Data, HG-520 
Reports, of tests of unidentified materials, HG-205.3 {see also 
Data Reports; Manufacturer's, master Data Reports; 
Manufacturer's, Partial Data Reports; Records) 
Requirements for safety and safety relief valves, HG-401 
Resistance welding, HW-600 
Retests of pressure parts {see Tests) 
Return, pipe connections {see Pipe) 

piping {see Pipe) 
Rewelding defective joints, HW-830 

Ring gaskets, HG-309, Fig. HG-309, HC-311.1, Fig. HC-311 
Rings, flange, from rods, bars, shapes, HF-202(a) 

flange, of spherically dished or shaped covers, HG-309, 
Fig. HG-309, HC-311, Fig. HC-311 

insulating, HG-200.7 

OG (Ogee), HG-312.4(g), Fig. HG-312.3 



reinforcing {see Rings, stiffening) 

stiffening, HG-312.3, Fig. HG-312.3, HG-312.4, HF-202(a), 
C-100, C-101 
Rivets, controlling brazed joint tolerance, HB- 1305(b) 
Rods, for pressure parts, HF-202 

specifications for, HF-202; Tables HF-300.1, HF-300.2 

stay, HG-345.1(c) 

unidentified, HF-205 
Rolled nonstandard pressure parts, HF-203.2 
Rolled standard pressure parts, HF- 203.1 
Rolling, direction of, HF-205. 2(a) 

of plain type furnaces, HG-312.1(c) 

S maximum allowable stress values, Tables HF-300.1, 

HF-300.2; HC-300 
Saddles, as reinforcement, HW-730.3 
Saddle-type fittings {see Fittings) 

Saddle-type pads, as reinforcement, telltale holes, HW-731.5 
Safety, strength of parts not computable for, Preamble 
Safety and safety-relief valves, HG-400, HLW-800 
accumulation tests, HG-512, B-100-B-102 
additional boiler heating surface, existing installations, 

HG-400. 1, HG-400.2(f) 
adjusted and sealed, HG-400. 1(a) 
capacity, discharge, HG-400, HG-402, Table HG-715 
examples of checking, B-101 
methods of checking, HG-512, B-100, B-102 
relieving, HG-400, HG-402 
required, HG-400 
casings, HG-400. 1(a) 
common connections, HG-701.2 
two or more valves, HG-701.2 
connections for, HG-701 
data sheets, test record, HG-402.9 

discharge, capacity {see Safety and safety piping, HG-701. 6 
disk, HG-401. 1(g), HG-401.2 
lifting devices, HG-401. 1(g) 
manufacturer's test reports, HG-402.9 
markings required, HG-402. 1, Fig. HG-402 
marking to constitute guarantee, HG-402. 1, HG-402.3 
maximum rise in pressure, HG-400. 1(e), HG-400.2(g), 

HG-400.3, HG-401. l(k) 
mounting, HG-701 

officially rated, HG-400. 1(a), HG-400.2(a) 
popping point tolerances, HG-401. l(k) 
relieving capacity {see Safety and safety relief) 
required, on boilers, HG-400. 1(a), HG-400.2(a) 
on hot water tanks, HG-400.3(a) 
on steam heat exchangers, HG-400.3(c) 
on water heat exchangers, HG-400.3(b) 
seals, HG-400. 1(a) 
seats, HG-401. 2(d) 
set pressure, HG-402.4, HG-402.5 
setting, HG-400. 1, HG-400.2 



245 



2007 SECTION IV 



size, HG-400.1(b), (c); HG-400.2(d) 

spring loaded, HG-40 1.1(f) 

spring pop type, HG-400.1(a) 

stamping with Code Symbol, HG-402.1, HG-402.2, 

Fig. HG-402 {see also Stamping) 
testing and stamping, HG-402 {see also Stamping; Tests) 
test record data sheets, HG-402.8 

tests, accumulation, HG-512, B-100-B-102 {see also Tests) 
to determine capacity, HG-402. 3 {see also Tests) 
coefficient method, HG-402.3(a) 
fluid medium used in tests, HG-402.7 
pressures, HG-402.4 
slope method, HG-402.3(b) 
three-valve method, HG-402.3(c) 
where and by whom conducted, HG-402.8 
threaded connections, HG-701.3 
Y-bases for, HG-701.1, HG-701.2 
Safety controls, primary, HG-605(a) 
Safety devices, HG-100 

design requirements, HG-40 1.5 
manufacturer's testing, HG-401.4 
manufacture and inspection, HG-40 1.3 
material selection, HG-40 1.2 
mechanical requirements, HG-40 1.1 
Safety factors, HG-307.4; Fig. HG-307; HG-320 [Note (1)]; 
Tables HF-300.1, HF-300.2 {see also Design, stress 
criterion) 
Safety limit switches, HG-640(a) 
Scope, of Code, Preamble 
ofPartHLW, HLW-100 
Screwed fittings or valves, HG-320.3(c), HG-370.1, HW-731.6 
{see also Fittings; Safety and safety-relief valves; Valves) 
Screwed stays and staybolts, HG-340.2, Fig. HG-340.2, 

HG-341.1, HG-341.2, HG-342.5 
Seals, safety valves, HG-400.1(a) 

water, HG-605(c) 
Seal welding, HG-307.4, Fig. HG-307 
Seats in tube holes, HG-360.1(a) 
Selection of materials, HG-200, HF-200, HW-500, HB-1100, 

HC-200 
Semiautomatic arc welding process, HW-701 
Semicircular furnaces, HG-312.8 
Serial Numbers, manufacturer's, HG-530. 1(a)(5); 

Figs. HG-530.2, HG-530.3 
Service, restrictions or exceptions, boilers, HG- 101.1 
hot- water supply boilers, HG- 10 1.1(b) 
lined potable-water heaters, HLW-101 
temperatures, furnaces, plain type, HG-312.1(b) 
ring-reinforced type, HG-3 12.4(f) 
hot-water boilers, HG-lOl.l(b), HG-101.2 
hot-water supply boilers, HG-lOl.l(b), HG-101.2 
water heaters, HLW-101, HLW-102 
water storage tanks, HLW-101, HLW-102 
Services in excess of Code limits, HG-101.2 



Setting, of boilers, HG-720, HG-725 

of safety valves, steam boilers, HG-400. 1 

of safety-relief valves, hot-water boilers, HG-400.2 

water heaters, HLW-800.1(b) 
of safety and safety-relief valves, 
tank and heat exchangers, HG-400.3 
Shapes, HF-202, HF-205 
Shear, in brazed joints, HB- 1307(a) 

in welded joints, HW-730.1, HW-730.2 
Sheets, attached to shell, HW-711.1, HW-711.2 
crown, HW-712.1, HW-712.2 
diagonal stays for tube, HG-343.2 
furnace, HW-712.1, HW-712.2 
tube, classified as shell plates, ferrous, HF-301.1(b) 

nonferrous, HF-301.2(b) 
wrapper, HW-711.2 
Shell axis, openings parallel to, HG-350.2 

openings transverse to, HG-350.3 
Shells, allowable working pressure, HG-300(b), (c) 
circumferential joints of, HW-701. 1 
computation of openings in, D-100; D-101; Figs. D-100, D- 

101 
design pressure, HG-300(a), HG-301, HG-305.1-HG-305.5, 

HC-400, HLW-300(a) 
extended, HW-7 11.1(g), HW-7 11.2(d) 
heads attached to, HG-305.7, HG-307.4, HW-715 
longitudinal joints of, HW-701.1 
materials for {see Materials; Plates) 
minimum thickness of, HF-301.1, Table HF-301.1, 

HF-301.2, Table HF-301.2, HLW-301 
openings, computations {see Shells, computation of 

openings in) 
reinforcement of openings in {see Openings and 

reinforcements, reinforcement requirements for) 
staying of, HG-340 

welded to heads or tubesheets, HW-7 11 
Shielded carbon arc welding process, HW-600(a) 
Shielded metal arc welding process, HW-600(a) 
Shutoff valves prohibited, HG-604, HG-605, HG-701.5 
Siphons, in pressure control connections, HG-605 

in steam-gage connections, HG-602 
Skirts, nonstandard pressure parts, HF-202(b) 
on heads, HG-305.1, HG-305.2, HG-305.6, HG-305.8, 
HW-715, HC-310.2 
Socket-type joints, HB-1304(a) 
Spacing, of brackets, lugs, hangers, HG-725 
of openings and tube holes, HG-346, HG-350, 

Figs. HG-350. l-HG-350.4 
of stays and staybolts, HG-340; Table HG-340; 

Fig. HG-343; HG-345; Figs. HG-345.1(a), HG-345.1(b) 
Specifications for materials {see Materials) 
Specification title, materials not limited by, HG-200.4 
Spherically dished covers (bolted heads), HG-309, 
Fig. HG-309, HC-311, Fig. HC-311 



246 



2007 SECTION IV 



Spherically dished heads, HG-309, Fig. HG-309, HC-311.1, 

Fig. HC-311 
Spherically shaped covers, Fig. HG-309, HC-311, Fig. HC-311 
Spherical radius factor K x , Table HG-321 
Spring loading of safety-relief valves, HG-400.2(a) 
Spring pop-type safety valves, HG-400.1(a) 
Stamping, arrangement, Figs. HG-530.1, HG-530.2; HG-530.2; 
HG-531 {see also Markings, arrangement of) 
location, brazed boilers, Figs. HG-530.1, HG-530.3, 
HG-530.6, HG-530.7; HB-1510 
cast boilers, HG-530.2 
valves, safety and safety relief, HG-402.1 
wrought boilers, HG-530.1 (b)-(d) 
nameplates, HG-402.1; HG-530.1; HG-530.2(b)-(d); 
Figs. HG-530.2, HG-530.3, HG-530.6, HG-530.7; 
HB-1510; HLW-602.1; Fig. HLW-602.2 
requirements, all boilers, HG-530, HG-530.1 

boiler parts and accessories, HG-531, HF-203, HF-205, 

HF-210 
brazed boilers, HB-1510 
cast iron boilers, HG-530.2 
field-assembled boiler pressure parts, HG-533 
field-assembled wrought boilers, HG-532 
of hot-water heaters, HLW-602 
other than cast iron, HG-530.1 
valves, HG-402.1, Fig. HG-402 
symbols, HG-402.1; Fig. HG-402; HG-530.1; HG-530.2; 
Figs. HG-530. l-HG-530.3, HG-530.6, HG-530.7; 
HG-533.5; Fig. HLW-602.1 
transferring of {see Markings) 
Stamps, administrative fee for, HG-540.2(b) 

ASME official symbols, HG-402.1, Fig. HG-402, HG-530.1, 
HG-530.2, Figs. HG-530. l-HG-530.7, HLW-602.1, 
Fig. HLW-602.2, HLW-602.3 
authorization to use, HG-402.2, HG-402.9, HG-533, 

HG-540.1, HLW-102, HLW-602.1 
Certificates of Authorization to use, HG-402.2, HG-530.2, 
HG-533.5, HG-540.2(b), HLW-602.1 
application for, HG-402.2, HG-533.5, HG-540.2(a) 
cancellation of, HG-540.2(c) 
regulations concerning use of, HG-540.2 
renewal of, HG-540.2(c) 
Stayed heads, HG-305.5, HG-345 
Stayed shells, HG-340.1 
Stayed surfaces, HG-340, HG-341.1, HG-343.1 
Stayed tubesheets, HG-343.2, HG-346 
Stayed wrapper sheets, HW-701.2 

Stays, staybolts, stay rods and stay tubes, adjacent to upper 
corners of fireboxes, pitch, Fig. HG-340. 1 
allowable stress on, Table HF-300.1 
area supported by, HG-342.2, HG-345. 1 
cross-sectional area, minimum, HG-342.1, HG-342.5 
diagonal, HG-343, Fig. HG-343 



acceptable and unacceptable types, Figs. HW-7 10.4(a), 
HW-7 10.4(b) 

diameters, minimum, HG-342.6 

dimensions of, HG-342, HG-343 

distance to corner joints, etc., HG-340.5 

ends riveted over, HG-341.1 

ends welded over, HG-345. 1(b) 

fabricated by welding, HG-342. 4 

hollow, HG-341.1 

load carried by, HG-342.2 

location, corner joints, welded joints, 
and flanges, HG-340.5 

material, HG-342.6, Tables HF-300.1, HF-300.2 

pitch, HG-340.3, HG-340.6, Fig. HG-340.1, Table HG-340 

proportions, through-stays with washers, HG-340.2 

telltale holes in, HG-341.1 

threaded, HG-341.1-HG-341.3 

unsymmetrical, HG-340.4 

upset, HG-341.2 

welded-in, HG-341.4, HW-7 10 
Steam flowmeters, calibrated, HG-402.7 
Steam gages, HG-602 {see also Gages) 
Steam generating capacity, B-100-B-102 
Steam heating boilers, in battery, Figs. HG-703.1(a), 
HG-703.1(b) 

safety valve requirements, HG-400.1(a) 

service restrictions and exceptions, HG-lOl.l(a), 5-200 
Steam mains, HG-703.1, Figs. HG-703.1(a), HG-703.1(b) 
Steam pipe, valveless header, HG-701.1 
Steam piping, HG-703, Figs. HG-703.1(a), HG-703.1(b) 
Steel, alloy, HW-500(a) 

bars, HF-202 

bolting, Table HF-300.1 

carbon, Figs. HG-312.1, HG-312.2; Table HF-300.1, 
HW-500(a) 

cast, HF-203. 1, HF-203.2, Table HF-300.1 

fittings, HF-203. 1, HF-203.3 

flanges, HF-203.1, HF-203.3, Table HF-300.1 

forgings, HF-203. l-HF-203.3, Table HF-300.1 

pipe, butt welded, Table HF-300.1 

electric resistance welded, Table HF-300.1 
lap welded, Table HF-300.1 
seamless, Table HF-300.1 

plate, HF-201, HF-205.2(a), HF-301.1, Tables HF-300.1, 
HF-301.1 

stays, HG-345.2, HF-202, Table HF-300.1 
Stiffening rings, HG-312.4, HF-202(a), HG-312.5, C-101 
Stop valves {see Valves) 

Strain measurement tests, HG-502.1 {see also Tests) 
Strength in reinforcements, of added material, HG-327.1 

of attachment material, HG-327.2 

of nozzles, HG-327.1 

of weld metal, HG-327.1 



247 



2007 SECTION IV 



Stresses, maximum allowable, in ferrous materials, 
Tables HF-300.1, HC-300 

in nonferrous materials, Table HF-300.2 

for lined materials, Table HLW-300 

for unlined materials, HLW-301 
Stress values for weld metal, HW-730.2, HLW-430.2 
Strips, backing, HW-701.3, Fig. HW-701.3, HW-702, 

HW-73 1.2(a) 
Structural shapes, HF-202 
Stud welding, HW-802.4, HW-820.6, HLW-431.7, HLW-460.5 

material requirements for, HW-820.5 

procedure and performance qualification tests for, 
HW-820.5, HLW-460.6 
Studded connections, HG-320.3(c)(l) 
Studs, HW-500(b), HW-730.4, HW-820.6 
Submerged arc welding process, HW-600(a) 
Supply pipe connections, Figs. HG-703.1(a), HG-703.1(b); 

HG-703.2, HG-710.1, HG-710.2, HG-710.3 
Supports, HG-200.7, HG-725.5, HF-202(b), HW-71 1.1(a), 
HW-71 1.2(a), HC-320 

for boilers over 72 in. in diameter, HG-725.2 

for boilers between 54 in. and 72 in. in diameter, HG-725.3 

for boilers up to 54 in. in diameter, HG-725.4 
Surfaces, brazed, HB-1400 

gasket {see Gaskets) 

on heads {see Heads, flat) 

stayed {see Stayed surfaces) 

to be welded, HW-801 {see also Welded joints) 
Suspension, outside, type of boiler setting, HG-725 
Switches, safety limit, HG-633, HG-640(a) 

shutdown, HG-634 
Systems, hot water, closed type, HG-709.2 

tank capacity, Tables HG-709.1, HG-709.2; HG-709.3 

open type, HG-709.1 

thermal expansion in, HG-709 

T- or lever handles for gage cocks, HG-602, HG-611 
Tack welds, HW-8 10(c) 

Tanks for hot water systems, HG-709, Tables HG-709.1, 
HG-709.2 
storage, HG-708, HLW-808 
Tapped holes, HG-370.1, HG-606(b), HG-701.1, HC-213(b), 

Table HC-213 
Tee joints, HW-701.3(a) {see also Joints) 
Tees, HG-330.4(e), HG-606(b), HC-325 
Telltale holes, HG-341.1, HW-730.3 
Temperature, controls, HG-613, HG-615(a), HLW-701 
design, HG-312.1(b), HG-3 12.4(f) 
gages, HG-612, HG-705 
maximum water, HG-lOl.l(a), HG-101.2, HG-613(a), 

HLW- 101. 2(b) 
pressure, ratings for flanges, HG-370.2 
pressure, safety relief valves, HG-400.2(b), HG-402.5, 
HC-402 



service, permissible, HG-101, HB-1303 
Tensile strength, of cast iron, HC-300, Table HC-300 

of ferrous materials, HF-300, Table HF-300.1 

of nonferrous materials, HF-300, Table HF-300.2 

tests to determine, HG-501.6, HG-502, HC-402 
Tension, in groove welds, HW-730 

maximum allowable stress values 

of cast iron in, HC-300, Table HC-300 
Test gages, HG-505, HC-402. 1 
Tests, 

accumulation, HG-512 

air, HW-730.3 

blowdown pressure, HG-402.3 

brittle coating, HG-502.4 

bursting, HG-502.3, HC-402 

capacity, discharge, HG-402.3, HG-402.6 

displacement measurement, HG-502.2 

hydrostatic, HG-503, HG-504, HG-510, HC-410, HLW-505 

leakage, HW-830 

lift pressure, HG-402.3 

of associated test bars, HC-402.2 

of completed boilers, HG-510, HC-410 

of duplicate parts, HG-504 

of individual sections, HC-410 

of materials not fully identified, HF-205 

of parts subject to collapse, HG-503, HLW-503 

of safety valves after design changes, HG-402.8 

opening test, HG-402.5 

physical, HF-204.1(e), HF-205.2 

popping pressure, HG-402.3 

pressure application, HG-501.4 

proof, HG-500-HG-504, HLW-502 

qualification, HW-600, HW-610-HW-613, HB-1001, 
HB-1102, HB-1103, HB-1201, HB-1202 

strain measurement, HG-502. 1 

tensile strength, HG-501.6 

to establish design pressure, HC-400 

transverse test, HC-209-HC-212 

types of, HG-501.1 

yield strength, HG-501.6 
Thermal cutting, HW-801(b) 
Thermal elements, HG-405 
Thermal expansion, HG-709, HLW-809 
Thermal gouging, HW-820.1 
Thermit welding, HW-600 

Thermometers, HG-612, HG-615, HG-621, HLW-820 
Thicknesses, exceeding specification limits, HG-200.6 

maximum, of materials, HG-200.6 {see also Materials) 

minimum, of materials, HG-200.6, HF-301 
Tables HF-301. 1, HF-301. 2 
Threaded connections, HG-3 12.6(c), HG-320.3, HG-370.1, 

Table HG-370, HG-701.3, HW-73 1.7, Fig. HW-73 1 
Threads, HG-307.4, Fig. HG-307, HG-341.1, HG-370.1, 
HC-213(b), Table HC-213 



248 



2007 SECTION IV 



Throats of fillet welds, HW-70 1.2(c), HW-7 11.1(d), 

HW-712.1(b), HW-731.4, HW-731.5 (see also Welds; 
Welding) 
Through-stays, HG-305.5(c), HG-340.2, HW-710, 

Fig. HG-340.2 (see also Stays) 
Time delay fuses, HG-632(a) 
Tolerances, alignment, buttjoints, HW-812 

clearance, for brazed joints, HB-1305, Table HB-1305 

set pressure, HG-401.1(k) 
Torch brazing, HB-1200 
Torispherical heads (dished) (see Heads) 
Trademarks (see Identification markings; Stamping) 
Transfer of markings on plate, HF-2 10(a) 
Transformer, isolation, HG-632(b) 
Tube ends, beading, HG-360.2 

expanding, HG-360.1, HG-360.2 

firetube boilers, HG-360.2(a), HG-360.2(b) 

flaring, HG-360.2 

recessed, HW-713, HW-73 1.2(b) 

welding of, HG-360.2, HW-713 
extension of, HW-713, Table HW-713 
Tube holes, HG-320.3, HG-321, HG-330.1, HG-350, HG-360, 

HW-713, HW-73 1.2 (see also Holes) 
Tubes, as stays, HG-346 

as supports, HG-346, HW-7 11.1(a), HW-7 11.2(a) 

attached by welding, HW-713, HLW-413 

attachment of, HG-360.2, HLW-309 

in heat exchangers, HG-400.3 

integrally finned, HF-204.1 

thickness, minimum, HLW-307 
Tubesheets, HG-343.2, HG-346, HG-360, HF-301.1, HF-301.2, 
Tables HF-301.1, HF-301.2; HW-7 11, HB-1302, 
HLW-411 
Tube spacing, HG-350, Figs. HG-350. l-HG-350.4 
Tubing, HG-602(a), HG-605(c), HG-611(c) 
Two-wire control circuits, HG-632 

Unequal spacing of openings, HG-350.2(b), Figs. HG-350.2, 

HG-350.3; HG-350.4(b) 
Unflanged heads, HG-345.1, HG-345.3, HW-7 11.2 
Unflanged manhole rings, HG-323.3(b) 
Unidentified materials, HG-200.3, HG-200.7, HF-202(b), 

HF-203.1(b) 
Unreinforced openings, HG-320.3 
Unstayed flanged-in openings, HG-323.3(b) 
Unstayed heads, HG-305.6, HG-307.1, HG-307.2, 

Fig. HG-307, HG-320.3(c), HG-345.1 
Unstayed noncircular covers and blind flanges, HG-307. 3, 

Fig. HG-307 
Unsymmetrical spacing of staybolts, HG-340.4 

Vacuum boilers, HG-300.1 

V-Symbol, authorized Code Stamp for valves, HG-402.1, 
Fig. HG-402 



Values, of C in flat head design, HG-307 .4 

of F in determining area of reinforcement, HG-321. 2, 
Fig. HG-321 

of K\, spherical radius factor, Table HG-321 
Valves, blowoff, Figs. HG-703.1, HG-703.2; HG-715, 
Table HG-715 

bottom drain (see Valves, blowoff) 

capacity tests, safety valves (see Tests) 

check, Fig. HG-703.1 

drain, HG-603(a), HG-604(a) (see also Valves, blowoff) 

feedwater (see Valves, supply; Valves, water inlet) 

pressure reducing, Fig. HG-703.2 

safety and safety-relief (see Safety and safety relief valves) 

shutoff, prohibited, HG-605(c), HG-701.5 

stop, HG-710 

supply, HG-710 

swing check, Fig. HG-703.1 

temperature and pressure safety relief , HG-402. 5, 
HG-402.6, HG-405 

water inlet, HG-606 (see also Identification markings; 
Materials; Mountings; Stamping) 
Valved fittings, HG-603 
Valveless headers, HG-701.1 
Valveless steam pipe between boilers, HG-701.1 
Vents, open, in open expansion tank systems, HG-709.1 
Vertical firetube boilers, HG-330.2, HG-330.4, HG-350.2 
Visibility of instruments, HG-621 
Visual examination of joints, HW-73 1.2, HW-73 1.3(b), 
HB-1301, HB-1304, HB-1503 

Washout openings, HG-330.1, HG-330.4(e), HC-325 

Washout plugs, HG-330.4 

Water columns, HG-602(a), HG-603, HG-604, HG-705 

Water equalizing pipe connections, HG-606(c) 

Water, feed, connections, HG-705 

Water feeding devices, HG-606 

Water gage glasses, HG-603, HG-604, HG-606 

Water heaters, lined potable, Part HLW 

Water level control pipes, HG-604(a) 

Waterlegs, HG-330.4, HG-341.1 

Water, low, fuel cutoffs, HG-606, HG-614 

Water outlets on boilers, HG-701.1 

Water seals, for pressure controls, HG-605(c) 

for steam gages, HG-602(a) 
Water supply connections, HLW-805 
Watertube boilers, HG-315, HG-530.2 
Weld defects, HW-830, HLW-460.4 
Welded connections, HW-730, HW-73 1, Fig. HW-73 1 
Welded-in staybolts, HG-341.1 
Welded joints, alignment tolerances, HW-812 

assembly of, HW-810 

butt, HW-70 1.1, HW-702, HW-812, HW-820, HLW-401.1 

circumferential, HW-701.1, HW-812 

corner, HW-701.3, HLW-401.2 



249 



2007 SECTION IV 



defects in, HW-830 

design of, HW-700, HW-701, HLW-400 

double-welded butt, HW-701. 1, HW-702, HW-820.1, 
HLW-460.1 

double-welded lap, HW-702 

efficiencies, HW-702, HW-703, HLW-402 

fillet, HW-710, HW-711, HW-730, HW-731, HW-820.2, 
HLW-460.2 

for stays, HG-341.4, Fig. HG-343, HW-710 

full fillet, HW-701.2, HW-701.3, Fig. HW-701.3, HW-712 

full penetration, HW-701.3, Fig. HW-701.3, HW-712.2, 
HW-731 

fusion {see Welding) 

groove, HW-730, HW-731. 2 

inspection during fabrication, HW-900 

lap, HW-701.2 

longitudinal, HW-701. 1, HW-812 

openings in, HW-720 

partial penetration, HW-731 

repair of defective, HW-830 

requirements for, HW-700, HW-701, HW-820 

single-bevel, HW-731 

single-J, HW-731 

single-welded butt, HW-701.1, HW-702 

single-welded lap, HW-701.2, Fig. HW-701.3 

tee, HW-701.3, Fig. HW-701.3, HLW-401.2 {see also 
Joints) 
Welded parts, minimum thicknesses of, HW-703 
Welded standard pressure parts, HF-203.3 
Welded stays, HG-340.3, HG-342.4, HG-342.5, HG-345.1(b), 

HW-710 
Welders and welding operators, HG-533.1, HW-401, HW-610, 

HW-611, HW-612, HW-613, HW-911 
Welding, caps, HF-203.3(a) 

fusion, HG-307.4, HG-312.6, HG-342.5, HW-701.1 

necks, HF-203.3(a) 

nozzles, HW-731, Fig. HW-731 

of boilers with two or more courses, HW-701. 1(a) 

of circumferential joints, corrugated furnaces, HG-312.6 

of crown sheets to heads, HW-712 

of furnace sheets to heads, HW-712 

of heads of shells, HW-711, HW-715 

of internally threaded fittings, HW-731. 6, Fig. HW-731 

of longitudinal joints, corrugated furnaces, HG-312.6 

of nonpressure parts to pressure parts, posthydrotest, 
HW-840, HLW-454 



of stays, HG-341.4, HG-342.4, HG-342.5, HW-710 

of tubes, HW-713 

of tubesheets, HW-711 

pipe couplings, HB- 1306(b) 

plasma arc, E-100 

processes, HW-600, HLW-440 

specific requirements for, HW-820 

spot, HG- 1305(b) 

test, HW-910, HW-911 
Weld metal (filler metal) allowable stress values, HW-730.2 

as reinforcement, HG-326.4 

depositing of, HW-701.1, HW-820 {see also Metals) 
Welds, attachment, requirements for, HW-731, HLW-431, 
HLW-431.1 

openings in, HW-720 

strength of, HW-730. 1 

repair of defects in, HW-830 

tack, HW-810 

tightness tests of, HW-730.3 
Wet-bottom boilers, HG-720 
Wiring, electric, circuit breakers, HG-634 

electrical code compliance, HG-631 

flame safeguard controls, HG-640 

limit controls, HG-633 

safety controls for heat generating apparatus, HG-640 

shutdown switches, HG-634 

type circuitry, HG-632 
Working pressures, allowable definition of, HG-300(c) 

for heads and covers, HG-305, HG-307, HG-309, HLW-305 

for hot water heating boilers, HG-101.1 

for hot water supply boilers, HG-101.1 

for shells, pipe and headers, HG-301, HLW-300 

for stayed surfaces, HG-340 

for steam boilers, HG-101.1 

for steel flanges and fittings, HG-307, HG-370.2 

maximum, HG-300 

tests to establish, HG-501-HG-504, HC-400, HC-401, 
HLW-300 
Wrapper sheets, HW-701.2 
Wrought iron pipe or tube, HG-315.1, Table HG-315, 

HG-602(a), HG-604, HG-605, Table HF-300.1 
Wrought materials, HF-100, HF-200, Tables HF-300.1, 
HF-300.2 

Y-fittings and bases, HG-606(b), HG-701.1, HG-701.2 
Yield point, HG-501.6 
Yield strength, HG-501.6 



250 



ASME Boiler and Pressure Vessel Code 
SECTION IV 



INTERPRETATIONS 
Volume 57 



Interpretations of the Code are distributed annually in July with the issuance of the edition and 
subsequent addenda. Interpretations posted in January at www.cstools.asme.org/interpretations are 
included in the July distribution. Interpretations of Section III, Divisions 1 and 2, are part of the update 
service to Section III, Subsection NCA. 

Interpretations Volumes 54 through 56 were included with the update service to the 2004 Edition of 
the Code; Volume 57 is the first Interpretations volume to be included with the update service to the 
2007 Edition. 



Section 



Vol. 57 



Vol. 58 



Vol. 59 







7/07 


ll-A 




7/07 


ll-B 






ll-C 






ll-D (Customary) 


7/07 


ll-D (Metric) 




lll-NCA 




7/07 


III-3 




7/07 


IV 




7/07 


V 




7/07 


VI 






VII 






VIII-1 




7/07 


VIII-2 




7/07 


VIII-3 




7/07 


IX 




7/07 


X 






XI 




7/07 


XII 







Copyright © 2007 

THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS 

All rights reserved 



SECTION IV — INTERPRETATIONS VOL. 57 



INTERPRETATIONS 
VOLUME 57 — SECTION IV 

Replies to Technical Inquiries 
January 1, 2006 Through December 31, 2006 

FOREWORD 

This publication includes all written interpretations issued between the indicated dates by the ASME Staff 
on behalf of the ASME Boiler and Pressure Vessel Committee in response to inquiries concerning interpreta- 
tions of the ASME Boiler and Pressure Vessel Code. A contents is also included which lists subjects specific 
to the interpretations covered in the individual volume. 

These interpretations are taken verbatim from the original letters, except for a few typographical and 
editorial corrections made for the purpose of improved clarity. In some instances, a review of the interpretation 
revealed a need for corrections of a technical nature. In these cases, a revised interpretation is presented 
bearing the original interpretation number with the suffix R and the original file number with an asterisk. 
Following these revised interpretations, new interpretations and revisions to them issued during the indicated 
dates are assigned interpretation number in chronological order. Interpretations applying to more than one 
Code Section appear with the interpretations for each affected Section. 

ASME procedures provide for reconsideration of these interpretations when or if additional information 
is available which the inquirer believes might affect the interpretation. Further, persons aggrieved by an 
interpretation may appeal to the cognizant ASME committee or subcommittee. As stated in the Statement 
of Policy in the Code documents, ASME does not "approve," "certify," "rate," or "endorse" any item, 
construction, proprietary device, or activity. 

An interpretation applies either to the Edition and Addenda in effect on the date of issuance of the 
interpretation or the Edition and Addenda stated in the interpretation. Subsequent revisions to the Code may 
supersede the interpretation. 

For detailed instructions on preparation of technical inquiries to the ASME Boiler and Pressure Vessel 
Committee, refer to Appendix B. 



279 



SECTION IV — INTERPRETATIONS VOL. 57 



SECTION IV 



Subject Interpretation File No. 

Clarification Request for HG-709.2 IV-07-01 BC06-526 

Clarification Request for Pressure Relief Devices IV-04-15 BC06-157 



280 



SECTION IV — INTERPRETATIONS VOL. 57 



Interpretation: IV-04-15 

Subject: Clarification Request for Pressure Relief Devices 
Date Issued: February 21, 2006 
File: BC06-157 

Question (1): Does a utility-closed loop, heating or cooling water system that contains air separators, heat 
exchangers, and expansion tanks that are ASME Section VIII, Division 1 stamped with MAWP greater than 
15 psi at temperatures greater than 250°F fall within the scope of ASME Section IV? 

Reply (1): No. 

Question (2): Does ASME Section IV cover a utility-closed loop, heating or cooling water system that 
contains air separators, heat exchangers, and expansion tanks that are ASME Section VIII stamped that 
operate at temperatures greater than 250°F at pressures greater than 15 psi? 

Reply (2): No. 



Interpretation: IV-07-01 

Subject: Clarification Request for HG-709.2 
Date Issued: August 20, 2006 
File: BC06-526 

Question (1): Is the expansion tank required by HG-709.2 for a boiler designed for a MAWP of 30 psi 
required to be constructed in accordance with ASME Section VII, Division 1 or Section X? 

Reply (1): No. 

Question (2): Is an expansion tank constructed in accordance with ASME Section VIII, Division 1 or 
Section X required for a heating system with a boiler designed for a MAWP of 50 psi? 

Reply (2): Yes. See HG-709.2. 

Question (3): Is an expansion tank constructed in accordance with ASME Section VIII, Division 1 or 
Section X required when a boiler constructed to a design pressure greater than 30 psi is installed regardless 
of system operating pressure? 

Reply (3): Yes. 



281 



282 



ISBN-13: 978-0-7918-3064-2 
ISBN-10 : 0-7918-3064-0 




9 780791H830642I 




U00040 



#