Power Piping: ASME Code for Pressure Piping, B31

382 Pages·11.009 MB·English

ASME B31.1-2018
(Revision of ASME B31.1-2016)
Power Piping
ASME Code for Pressure Piping, B31
AN INTERNATIONAL PIPING CODE®
ASME B31.1-2018
(Revision of ASME B31.1-2016)
Power Piping
x
ASME Code for Pressure Piping, B31
AN INTERNATIONAL PIPING CODE®
Two Park Avenue • New York, NY • 10016 USA
x
DateofIssuance:July20,2018
ThenexteditionofthisCodeisscheduledforpublicationin2020.ThisCodewillbecomeeffective6monthsaftertheDateof
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TheAmericanSocietyofMechanicalEngineers
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Copyright©2018by
THEAMERICANSOCIETYOFMECHANICALENGINEERS
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CONTENTS
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Committee Roster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xii
Summary of Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Chapter I Scope and Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
100 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Chapter II Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
PART 1 Conditions and Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
101 Design Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
102 Design Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
PART 2 Pressure Design of Piping Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
103 Criteria for Pressure Design of Piping Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
104 Pressure Design of Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
PART 3 Selection and Limitations of Piping Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
105 Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
106 Fittings, Bends, and Intersections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
107 Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
108 Pipe Flanges, Blanks, Flange Facings, Gaskets, and Bolting . . . . . . . . . . . . . . . . . . . . . . . . 38
PART 4 Selection and Limitations of Piping Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
110 Piping Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
111 Welded Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
112 Flanged Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
113 Expanded or Rolled Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
114 Threaded Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
115 Flared, Flareless, and Compression Joints, and Unions . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
116 Bell End Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
117 Brazed and Soldered Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
118 Sleeve Coupled and Other Proprietary Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
PART 5 Expansion, Flexibility, and Pipe-Supporting Element . . . . . . . . . . . . . . . . . . . . . . . . . . 45
119 Expansion and Flexibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
120 Loads On Pipe-Supporting Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
121 Design of Pipe-Supporting Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
PART 6 Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
122 Design Requirements Pertaining to Specific Piping Systems . . . . . . . . . . . . . . . . . . . . . . . 52
Chapter III Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
123 General Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
124 Limitations On Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
125 Creep Strength Enhanced Ferritic Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
iii
Chapter IV Dimensional Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
126 Material Specifications and Standards for Standard and Nonstandard Piping
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Chapter V Fabrication, Assembly, and Erection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
127 Welding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
128 Brazing and Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
129 Bending and Forming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
130 Requirements for Fabricating and Attaching Pipe Supports . . . . . . . . . . . . . . . . . . . . . . . 95
131 Welding Preheat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
132 Postweld Heat Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
133 Stamping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
135 Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Chapter VI Inspection, Examination, and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
136 Inspection and Examination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
137 Pressure Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Chapter VII Operation and Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
138 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
139 Operation and Maintenance Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
140 Condition Assessment of CPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
141 CPS Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
142 Piping and Pipe-Support Maintenance Program and Personnel Requirements . . . . . . . . . . 114
144 CPS Walkdowns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
145 Material Degradation Mechanisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
146 Dynamic Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Mandatory Appendices
A Allowable Stress Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
B Thermal Expansion Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
C Moduli of Elasticity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
D Flexibility and Stress Intensification Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
F Referenced Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
G Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
H Preparation of Technical Inquiries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264
N Rules for Nonmetallic Piping and Piping Lined With Nonmetals . . . . . . . . . . . . . . . . . . . . 266
O Use of Alternative Ultrasonic Acceptance Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
P Metallic Bellows Expansion Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298
Nonmandatory Appendices
II Rules for the Design of Safety Valve Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
IV Corrosion Control for ASME B31.1 Power Piping Systems . . . . . . . . . . . . . . . . . . . . . . . . 323
V RecommendedPracticeforOperation,Maintenance,andModificationofPowerPipingSystems 327
VII Procedures for the Design of Restrained Underground Piping . . . . . . . . . . . . . . . . . . . . . . 341
VIII Guidelines for Determining if Low-Temperature Service Requirements Apply . . . . . . . . . . 352
iv
Figures
100.1.2-1 CodeJurisdictionalLimitsforPiping—AnExampleofForcedFlowSteamGeneratorsWithNo
Fixed Steam or Waterline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
100.1.2-2 CodeJurisdictionalLimitsforPiping—AnExampleofSteamSeparatorTypeForcedFlowSteam
Generators With No Fixed Steam or Waterline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
100.1.2-3 Code Jurisdictional Limits for Piping — Drum-Type Boilers . . . . . . . . . . . . . . . . . . . . . . . 5
100.1.2-4 CodeJurisdictionalLimitsforPiping—IsolableEconomizersLocatedinFeedwaterPipingand
Isolable Superheaters in Main Steam Piping (Boiler Pressure Relief Valves, Blowoff, and
Miscellaneous Piping for Boiler Proper Not Shown for Clarity) . . . . . . . . . . . . . . . . . . . 6
100.1.2-5 Code Jurisdictional Limits for Piping — Reheaters and Nonintegral Separately Fired
Superheaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
100.1.2-6 Code Jurisdictional Limits for Piping — Spray-Type Desuperheater . . . . . . . . . . . . . . . . . . 8
100.1.2-7 Code Jurisdictional Limits for Piping — HRSG — Desuperheater Protection Devices . . . . . 9
102.4.5-1 Nomenclature for Pipe Bends . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
104.3.1-1 Reinforcement of Branch Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
104.3.1-2 Reinforced Extruded Outlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
104.5.3-1 Types of Permanent Blanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
104.8.4-1 Cross Section Resultant Moment Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
122.1.7-1 Typical Globe Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
122.4-1 Desuperheater Schematic Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
127.3-1 Butt Welding of Piping Components With Internal Misalignment . . . . . . . . . . . . . . . . . . . 82
127.4.2-1 Welding End Transition — Maximum Envelope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
127.4.4-1 Fillet Weld Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
127.4.4-2 Welding Details for Slip-On and Socket-Welding Flanges; Some Acceptable Types of Flange
Attachment Welds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
127.4.4-3 MinimumWeldingDimensionsRequiredforSocketWeldingComponentsOtherThanFlanges 87
127.4.8-1 Typical Welded Branch Connection Without Additional Reinforcement . . . . . . . . . . . . . . . 87
127.4.8-2 Typical Welded Branch Connection With Additional Reinforcement . . . . . . . . . . . . . . . . . 87
127.4.8-3 Typical Welded Angular Branch Connection Without Additional Reinforcement . . . . . . . . . 88
127.4.8-4 SomeAcceptableTypesofWeldedBranchAttachmentDetailsShowingMinimumAcceptable
Welds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
127.4.8-5 Some Acceptable Details for Integrally Reinforced Outlet Fittings . . . . . . . . . . . . . . . . . . . 90
127.4.8-6 TypicalFullPenetrationWeldBranchConnectionsforNPS3(DN80)andSmallerHalfCouplings
or Adapters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
127.4.8-7 TypicalPartialPenetrationWeldBranchConnectionforNPS2(DN50)andSmallerFittings 92
135.5.3-1 Typical Threaded Joints Using Straight Threads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
D-1 Branch Connection Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
D-2 Flexibility Factor, k, and Stress Intensification Factor, i . . . . . . . . . . . . . . . . . . . . . . . . . . 252
D-3 Correction Factor, c . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
N-100.2.1-1 Winding Angle of Filament-Wound Thermosetting Resin Pipe . . . . . . . . . . . . . . . . . . . . . . 269
N-102.3.1-1 Typical Allowable Stress Curve for Filament-Wound Reinforced Thermosetting Resin Pipe . 275
N-127.7.1-1 Solvent-Cemented Joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
N-127.7.2-1 Heat Fusion Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
N-127.7.3-1 Thermoplastic Electrofusion Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
N-127.8.1-1 Thermosetting Resin Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
O-8-1 Surface and Subsurface Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
II-1.2-1 Safety Valve Installation (Closed Discharge System) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
v
II-1.2-2 Safety Valve Installation (Open Discharge System) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
II-2.2.1-1 Discharge Elbow (Open Discharge Installation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
II-2.2.1-2 Compressible Flow Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
II-2.2.1-3 Vent Pipe (Open Discharge Installation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309
II-3.5.1.3-1 Safety Valve Installation (Open Discharge System) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
II-3.5.1.3-2 Dynamic Load Factors for Open Discharge System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
II-6-1 Examples of Safety Valve Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
II-7-1 Sample Problem Figure 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
II-7-2 Sample Problem Figure 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
II-7.1.9-1 Sample Problem Figure 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
V-12.1.2-1 Effect of Various Steady Operating Temperatures On Time to Failure Due to Creep . . . . . . 337
VII-3.3.2-1 Element Category A, Elbow or Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345
VII-3.3.2-2 Element Category B, Branch Pipe Joining the P Leg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345
VII-3.3.2-3 Element Category C, Tee on End of P Leg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345
VII-3.3.2-4 Element Category D, Straight Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345
VII-5-1 Plan of Example Buried Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348
VII-6.4.4-1 Computer Model of Example Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
VII-6.6-1 Example Plan of Element 1 As a Category D Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351
Tables
102.4.3-1 Longitudinal Weld Joint Efficiency Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
102.4.5-1 Bend Thinning Allowance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
102.4.6-1 Maximum Severity Level for Casting Thickness 41⁄ in. (114 mm) or Less . . . . . . . . . . . . 21
2
102.4.6-2 Maximum Severity Level for Casting Thickness Greater Than 41⁄ in. (114 mm) . . . . . . . . 22
2
102.4.7-1 WeldStrengthReductionFactorstoBeAppliedWhenCalculatingtheMinimumWallThickness
orAllowableDesignPressureofComponentsFabricatedWithaLongitudinalSeamFusion
Weld . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
104.1.2-1 Values of y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
112-1 Piping Flange Bolting, Facing, and Gasket Requirements (Refer to Paras. 108, 110, and 112) 41
114.2.1-1 Threaded Joints Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
121.5-1 Suggested Steel Pipe Support Spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
121.7.2-1 Carrying Capacity of Threaded ASTM A36, A575, and A576 Hot-Rolled Carbon Steel . . . . . 51
122.2-1 Design Pressure for Blowoff/Blowdown Piping Downstream of BEP Valves . . . . . . . . . . . . 58
122.8.2-1 Minimum Wall Thickness Requirements for Toxic Fluid Piping . . . . . . . . . . . . . . . . . . . . . 64
126.1-1 Specifications and Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
127.4.2-1 Reinforcement of Girth and Longitudinal Butt Welds . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
129.3.1-1 Approximate Lower Critical Temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
129.3.3.1-1 Post Cold-Forming Strain Limits and Heat-Treatment Requirements for Creep-Strength
Enhanced Ferritic Steels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
129.3.4.1-1 PostCold-FormingStrainLimitsandHeat-TreatmentRequirementsforAusteniticMaterialsand
Nickel Alloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
131.4.1-1 Preheat Temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
132.1.1-1 Postweld Heat Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
132.1.1-2 AlternatePostweldHeatTreatmentRequirementsforCarbonandLowAlloySteels,P-Nos.1and
3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
132.1.3-1 Postweld Heat Treatment of P36/F36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
vi
132.2-1 Exemptions to Mandatory Postweld Heat Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
136.4.1-1 MandatoryMinimumNondestructiveExaminationsforPressureWeldsorWeldstoPressure-
Retaining Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
136.4.1-2 Weld Imperfections Indicated by Various Types of Examination . . . . . . . . . . . . . . . . . . . . 107
A-1 Carbon Steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
A-2 Low and Intermediate Alloy Steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
A-3 Stainless Steels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
A-4 Nickel and High Nickel Alloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
A-5 Cast Iron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
A-6 Copper and Copper Alloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
A-7 Aluminum and Aluminum Alloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
A-8 Temperatures 1,200°F and Above . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
A-9 Titanium and Titanium Alloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
A-10 Bolts, Nuts, and Studs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
B-1 Thermal Expansion Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
B-1 (SI) Thermal Expansion Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
C-1 Moduli of Elasticity for Ferrous Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
C-1 (SI) Moduli of Elasticity for Ferrous Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
C-2 Moduli of Elasticity for Nonferrous Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
C-2 (SI) Moduli of Elasticity for Nonferrous Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
D-1 Flexibility and Stress Intensification Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
N-102.2.1-1 HydrostaticDesignStresses(HDS)andRecommendedTemperatureLimitsforThermoplastic
Piping Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
N-102.2.1-2 Design Stresses (DS) and Recommended Temperature Limits for Laminated Reinforced
Thermosetting Resin Piping Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
N-102.2.1-3 Hydrostatic Design Basis (HDB) for Machine-Made Reinforced Thermosetting Resin Pipe . . 274
N-119.6.1-1 Thermal Expansion Coefficients, Nonmetals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
N-119.6.2-1 Modulus of Elasticity, Nonmetals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281
N-126.1-1 Nonmetallic Material and Product Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
N-136.4.1-1 Acceptance Criteria for Bonds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
O-9-1 Discontinuity Acceptance Criteria for Weld Thickness Under 1.0 in. (25 mm) . . . . . . . . . . 297
O-9-2 Surface Discontinuity Acceptance Criteria for Weld Thickness 1.0 in. (25 mm) and Over . . 297
O-9-3 Subsurface Discontinuity Acceptance Criteria for Weld Thickness 1.0 in. (25 mm) and Over 297
II-2.2.1-1 Values of a and b . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
IV-5.2-1 Erosion/Corrosion Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326
VII-3.2.3-1 Approximate Safe Working Values of C for Use in Modified Marston Formula . . . . . . . . . 344
D
VII-6.3-1 Equations for Calculating Effective Length L′ or L″ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
VIII-1 Low-Temperature Service Requirements by Material Group . . . . . . . . . . . . . . . . . . . . . . . 353
VIII-2 Material Groupings by Material Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Forms
V-7.5-1 Piping System Support Design Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
V-7.5-2 Hot Walkdown of Piping System Supports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
V-7.5-3 Cold Walkdown of Piping System Supports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
vii
FOREWORD
ThegeneralphilosophyunderlyingthisPowerPipingCodeistoparallelthoseprovisionsofSectionI,PowerBoilers,of
theASMEBoilerandPressureVesselCode,astheycanbeappliedtopowerpipingsystems.TheAllowableStressValues
forpowerpipingaregenerallyconsistentwiththoseassignedforpowerboilers.ThisCodeismoreconservativethan
someotherpipingcodes,reflectingtheneedforlongservicelifeandmaximumreliabilityinpowerplantinstallations.
ThePower PipingCode ascurrently writtendoesnot differentiateamongthedesign,fabrication, anderectionre-
quirements for critical and noncritical piping systems, except for certain stress calculations and mandatory nondes-
tructivetestsofweldsforheavywall,hightemperatureapplications.Theprobleminvolvedistotrytoreachagreementon
howtoevaluate criticality, andtoavoid the inference thatnoncritical systemsdo not requirecompetence in design,
fabrication,anderection.Somedaysuchlevelsofqualitymaybedefinable,sothattheneedforthemanydifferentpiping
codes will be overcome.
TherearemanyinstanceswheretheCodeservestowarnadesigner,fabricator,orerectoragainstpossiblepitfalls;but
the Code is not a handbook, and cannot substitute for education, experience, and sound engineering judgment.
NonmandatoryAppendicesareincludedintheCode.Eachcontainsinformationonaspecificsubject,andismaintained
currentwiththeCode.Althoughwritteninmandatorylanguage,theseAppendicesareofferedforapplicationattheuser's
discretion.
TheCodeneverintentionallyputsaceilinglimitonconservatism.Adesignerisfreetospecifymore-rigidrequirements
ashe/shefeelstheymaybejustified.Conversely,adesignerwhoiscapableofapplyingamorecompleteandrigorous
analysisconsistentwiththedesigncriteriaofthisCodemayjustifyamethoddifferentthanspecifiedintheCode,andstill
satisfy the Code requirements.
ThePowerPipingCommitteestrivestokeepabreastofthecurrenttechnologicalimprovementsinnewmaterials,
fabricationpractices,andtestingtechniques;andendeavorstokeeptheCodeupdatedtopermittheuseofacceptablenew
developments.
viii
ASME B31 COMMITTEE
Code for Pressure Piping
(ThefollowingistherosteroftheCommitteeatthetimeofapprovalofthisCode.)
STANDARDS COMMITTEE OFFICERS
J.E.Meyer,Chair
J.W.Frey,ViceChair
A.Maslowski,Secretary
STANDARDS COMMITTEE PERSONNEL
R.J.T.Appleby,ExxonMobilPipelineCo. A.Livingston,KinderMorgan
C.BechtIV,BechtEngineeringCo. A.Maslowski,TheAmericanSocietyofMechanicalEngineers
K.C.Bodenhamer,TRCPipelineServices W.J.Mauro,AmericanElectricPower
R.Bojarczuk,ExxonMobilResearchandEngineeringCo. J.E.Meyer,LouisPerryGroup
M.R.Braz,MRBraz&Associates T.Monday,TeamIndustries,Inc.
J.S.Chin,TransCanadaPipelineU.S. M.L.Nayyar,NICE
D.D.Christian,Victaulic G.R.Petru,AcapellaEngineeringServices,LLC
P.Deubler,BechtEngineeringCo.,Inc. D.W.Rahoi,CCM2000
D.Diehl,HexagonPPM R.Reamey,TurnerIndustriesGroup,LLC
C.Eskridge,Jr.,JacobsEngineering M.J.Rosenfeld,Kiefner/Applus—RTD
D.J.Fetzner,BPExplorationAlaska,Inc. J.T.Schmitz,SouthwestGasCorp.
P.D.Flenner,FlennerEngineeringServices S.K.Sinha,LuciusPitkin,Inc.
D.Frikken,BechtEngineeringCo. W.Sperko,SperkoEngineeringServices,Inc.
J.W.Frey,JoeW.FreyEngineeringServices,LLC J.Swezy,Jr.,BoilerCodeTech,LLC
R.A.Grichuk,FluorEnterprises,Inc. F.W.Tatar,FMGlobal
R.W.Haupt,PressurePipingEngineeringAssociates,Inc. K.A.Vilminot,CommonwealthAssociates,Inc.
G.Jolly,SamshinLimited J.S.Willis,PageSoutherlandPage,Inc.
K.Kaplan G.Antaki,Ex-Officio,BechtEngineeringCo.,Inc.
C.Kolovich L.E.Hayden,Jr.,Ex-Officio
B31.1 POWER PIPING SECTION COMMITTEE
W.J.Mauro,Chair,AmericanElectricPower B.P.Holbrook
K.A.Vilminot,ViceChair,CommonwealthAssociates,Inc. M.W.Johnson,NRGEnergy
U.D'Urso,Secretary,TheAmericanSocietyofMechanicalEngineers R.Kennedy,DTEEnergy
D.D.Christian,Victaulic D.J.Leininger,WorleyParsons
M.J.Cohn,Intertek W.M.Lundy,U.S.CoastGuard
R.Corbit,APTIM L.C.McDonald,StructuralIntegrityAssociates,Inc.
D.Creates,OntarioPowerGeneration,Inc. T.Monday,TeamIndustries,Inc.
P.M.Davis,AMECFosterWheeler M.L.Nayyar,NICE
P.Deubler,FronekPowerSystems,LLC J.W.Power,GEPower
A.S.Drake,ConstellationEnergyGroup D.W.Rahoi,CCM2000
M.Engelkemier,Cargill K.I.Rapkin,FPL
S.Findlan,Westinghouse R.Reamey,TurnerIndustriesGroup,LLC
P.D.Flenner,FlennerEngineeringServices J.P.Scott,Dominion
J.W.Frey,JoeW.FreyEngineeringServices,LLC J.J.Sekely,WeldingServices,Inc.
S.Gingrich,AECOM H.R.Simpson
J.W.Goodwin,SouthernCo. S.K.Sinha,LuciusPitkin,Inc.
J.Hainsworth,WRMetallurgical A.L.Watkins,FirstEnergyCorp.
T.E.Hansen,AmericanElectricPower R.B.Wilson,R.B.Wilson&AssociatesLtd.
R.W.Haupt,PressurePipingEngineeringAssociates,Inc. E.C.Goodling,Jr.,ContributingMember
C.Henley,KiewitEngineeringGroup,Inc. E.Rinaca,ContributingMember,DominionResources,Inc.
ix