Power Piping

ASME Code for Pressure Piping, B31

AN A MERICAN NA TIONAL S T AND ARD

ASME B31.1-2012

(Revision of ASME B31.1-2010)

ASME B31.1-2012

(Revision of ASME B31.1-2010)

Power Piping

ASME Code for Pressure Piping, B31

AN AMERICAN NA TIONAL S T AND ARD

Three Park Avenue • New York, NY • 10016 USA

Date of Issuance: June 29, 2012

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Copyright © 2012 by

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CONTENTS

Foreword vii

Committee Roster viii

Introduction xii

Summary of Changes xiv

iii

1. Postweld Heat Treatment 94

2. Stamping 101

1. Assembly 101

   Chapter VI Inspection, Examination, and Testing 103

2. Inspection and Examination 103

3. Pressure Tests 107

   Chapter VII Operation and Maintenance 110

4. General 110

5. Operation and Maintenance Procedures 110

6. Condition Assessment of CPS 110

7. CPS Records 111

1. CPS Walkdowns 111

2. Material Degradation Mechanisms 111

Figures

100.1.2(A.1) Code Jurisdictional Limits for Piping — An Example of Forced Flow

Steam Generators With No Fixed Steam and Water Line 2

100.1.2(A.2) Code Jurisdictional Limits for Piping — An Example of Steam Separator Type Forced Flow Steam Generators With No Fixed Steam and Water

Line 3

100.1.2(B) Code Jurisdictional Limits for Piping — Drum-Type Boilers 4

100.1.2(C) Code Jurisdictional Limits for Piping — Spray-Type Desuperheater 5

102.4.5 Nomenclature for Pipe Bends 17

104.3.1(D) Reinforcement of Branch Connections 24

104.3.1(G) Reinforced Extruded Outlets 28

104.5.3 Types of Permanent Blanks 31

104.8.4 Cross Section Resultant Moment Loading 33

122.1.7(C) Typical Globe Valves 55

122.4 Desuperheater Schematic Arrangement 59

127.3 Butt Welding of Piping Components With Internal Misalignment 79

127.4.2 Welding End Transition — Maximum Envelope 80

127.4.4(A) Fillet Weld Size 83

127.4.4(B) Welding Details for Slip-On and Socket-Welding Flanges; Some

Acceptable Types of Flange Attachment Welds 84

127.4.4(C) Minimum Welding Dimensions Required for Socket Welding

Components Other Than Flanges 84

127.4.8(A) Typical Welded Branch Connection Without Additional

Reinforcement 84

127.4.8(B) Typical Welded Branch Connection With Additional Reinforcement 84

127.4.8(C) Typical Welded Angular Branch Connection Without Additional Reinforcement 84

127.4.8(D) Some Acceptable Types of Welded Branch Attachment Details

Showing Minimum Acceptable Welds 85

127.4.8(E) Some Acceptable Details for Integrally Reinforced Outlet Fittings 86

127.4.8(F) Typical Full Penetration Weld Branch Connections for NPS 3 and

Smaller Half Couplings or Adapters 87

127.4.8(G) Typical Partial Penetration Weld Branch Connection for NPS 2 and

Smaller Fittings 88

135.5.3 Typical Threaded Joints Using Straight Threads 102

Tables

102.4.3 Longitudinal Weld Joint Efficiency Factors 16

1. Bend Thinning Allowance 17

   102.4.6(B.1.1) Maximum Severity Level for Casting Thickness 41⁄2 in. (114 mm) or

   Less 18

   102.4.6(B.2.2) Maximum Severity Level for Casting Thickness Greater Than 41⁄2 in.

   (114 mm) 18

   iv

   
   

   102.4.7	Weld Strength Reduction Factors to Be Applied When Calculating the Minimum Wall Thickness or Allowable Design Pressure of Components Fabricated With a Longitudinal Seam Fusion Weld ......	20
   104.1.2(A)	Values of y ............................................................	22
   112	Piping Flange Bolting, Facing, and Gasket Requirements ...............	39
   114.2.1	Threaded Joints Limitations ............................................	43
   121.5 121.7.2(A) 122.2	Suggested Pipe Support Spacing ....................................... Carrying Capacity of Threaded ASTM A36, A575, and A576 Hot-Rolled Carbon Steel ............................................. Design Pressure for Blowoff/Blowdown Piping Downstream of BEP Valves ..............................................................	48 50 56
   122.8.2(B)	Minimum Wall Thickness Requirements for Toxic Fluid Piping .........	63
   126.1	Specifications and Standards ...........................................	71
   127.4.2	Reinforcement of Girth and Longitudinal Butt Welds ...................	82
   129.3.1	Approximate Lower Critical Temperatures .............................	91
   129.3.4.1	Post Cold-Forming Strain Limits and Heat-Treatment Requirements .....	92
   132	Postweld Heat Treatment ..............................................	95
   132.1 136.4	Alternate Postweld Heat Treatment Requirements for Carbon and Low Alloy Steels .................................................... Mandatory Minimum Nondestructive Examinations for Pressure Welds or Welds to Pressure-Retaining Components ...................	100 105
   136.4.1	Weld Imperfections Indicated by Various Types of Examination .........	106
   Mandatory Appendices
   A	Allowable Stress Tables ................................................	113
   	Table A-1, Carbon Steel ................................................	114
   	Table A-2, Low and Intermediate Alloy Steel ...........................	126
   	Table A-3, Stainless Steels .............................................	136
   	Table A-4, Nickel and High Nickel Alloys ..............................	166
   	Table A-5, Cast Iron ...................................................	180
   	Table A-6, Copper and Copper Alloys ..................................	182
   	Table A-7, Aluminum and Aluminum Alloys ...........................	186
   	Table A-8, Temperatures 1,200°F and Above ............................	194
   	Table A-9, Titanium and Titanium Alloys ..............................	200
   	Table A-10, Bolts, Nuts, and Studs .....................................	204
   B	Thermal Expansion Data ..............................................	209
   	Table B-1, Thermal Expansion Data ....................................	210
   	Table B-1 (SI), Thermal Expansion Data ................................	214
   C	Moduli of Elasticity ...................................................	218
   	Table C-1, Moduli of Elasticity for Ferrous Material .....................	218
   	Table C-1 (SI), Moduli of Elasticity for Ferrous Material ................	219
   	Table C-2, Moduli of Elasticity for Nonferrous Material .................	220
   	Table C-2 (SI), Moduli of Elasticity for Nonferrous Material .............	222
   D	Flexibility and Stress Intensification Factors ............................	224
   	Table D-1, Flexibility and Stress Intensification Factors ..................	224
   	Chart D-1, Flexibility Factor, k, and Stress Intensification Factor, i .......	228
   	Chart D-2, Correction Factor, c .........................................	229
   	Fig. D-1, Branch Connection Dimensions ...............................	230
   F	Referenced Standards ..................................................	231
   G