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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.
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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.
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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.
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ISBN-13: 978-0-7918-3064-2
ISBN-10 : 0-7918-3064-0
9 780791H830642I
U00040
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