1、ASME B31.8-2003(Revision of ASME B31.8-1999)GASTRANSMISSIONAND DISTRIBUTIONPIPING SYSTEMS(Revision of AS E B31.8-1999)ASME CODE FOR PRESSURE PIPING, B31 AN AMERICAN NATIONAL STANDARDCANB31.8-2003 ASME B31.8-2003 ASME A04503Copyright ASME International Provided by IHS under license with ASMENot for R
2、esaleNo reproduction or networking permitted without license from IHS-,-,-AN AMERICAN NATIONAL STANDARDGAS TRANSMISSIONAND DISTRIBUTIONPIPING SYSTEMSASME B31.8-2003(Revision of ASME B31.8-1999)ASME CODE FOR PRESSURE PIPING, B31Copyright ASME International Provided by IHS under license with ASMENot f
3、or ResaleNo reproduction or networking permitted without license from IHS-,-,-Date of Issuance: February 6, 2004The next Edition of this Code is scheduled for publication in 2005. There will be no addenda issuedto this edition.ASME issues written replies to inquiries concerning interpretations of te
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10、ut the prior written permission of the publisher.Copyright 2004 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSThree Park Avenue, New York, New York, 10016-5990All Rights ReservedPrinted in U.S.A.Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or netw
11、orking permitted without license from IHS-,-,-CONTENTSForeword viiCommittee Personnel ixIntroduction . xiiSummary of Changes xivGeneral Provisions and Definitions801 General 1802 Scope and Intent . 1803 Piping Systems Definitions . 2804 Piping Systems Component Definitions . 4805 Design, Fabrication
12、, Operation, and Testing Terms 6807 Quality Assurance . 7Chapter I Materials and Equipment810 Materials and Equipment 8811 Qualification of Materials and Equipment 8812 Materials for Use in Cold Climates . 9813 Marking . 9814 Material Specifications . 9815 Equipment Specifications 9816 Transportatio
13、n of Line Pipe 10817 Conditions for the Reuse of Pipe . 10Chapter II Welding820 Welding . 12821 General 12822 Preparation for Welding . 12823 Qualification of Procedures and Welders . 12824 Preheating . 13825 Stress Relieving 13826 Inspection of Welds 14827 Repair or Removal of Defective Welds in Pi
14、ping Intended to Operate atHoop Stress Levels of 20% or More of the Specified Minimum YieldStrength . 15Chapter III Piping System Components and Fabrication Details830 Piping System Components and Fabrication Details . 16831 Piping System Components 16832 Expansion and Flexibility 22833 Design for L
15、ongitudinal Stress . 23834 Supports and Anchorage for Exposed Piping . 25835 Anchorage for Buried Piping . 26Tables831.42 Reinforcement of Welded Branch Connections, Special Requirements 21832.2 Thermal Expansion of Carbon and Low Alloy Steel . 22832.5 Modulus of Elasticity for Carbon and Low Alloy
16、Steel 23Chapter IV Design, Installation, and Testing840 Design, Installation, and Testing . 27841 Steel Pipe 29842 Other Materials 40843 Compressor Stations . 46iiiCopyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without licens
17、e from IHS-,-,-844 Pipe-Type and Bottle-Type Holders 49845 Control and Limiting of Gas Pressure 50846 Valves . 58847 Vaults . 58848 Customers Meters and Regulators . 59849 Gas Service Lines 60Tables841.114A Basic Design Factor, F . 30841.114B Design Factors for Steel Pipe Construction 31841.115A Lon
18、gitudinal Joint Factor, E 32841.116A Temperature Derating Factor, T, for Steel Pipe 32841.322(f) Test Requirements for Pipelines and Mains to Operate at HoopStresses of 30% or More of the Specified Minimum Yield Strength ofthe Pipe . 39841.33 Maximum Hoop Stress Permissible During Test 39842.214 Sta
19、ndard Thickness Selection Table for Ductile Iron Pipe 41842.32(c) Wall Thickness and Standard Dimension Ratio for Thermoplastic Pipe 42842.33(c) Diameter and Wall Thickness for Reinforced ThermosettingPlastic Pipe 42842.396(c) Nominal Values for Coefficients of Thermal Expansion of ThermoplasticPipe
20、 Materials . 44Chapter V Operating and Maintenance Procedures850 Operating and Maintenance Procedures Affecting the Safety of GasTransmission and Distribution Facilities 64851 Pipeline Maintenance 66852 Distribution Piping Maintenance . 71853 Miscellaneous Facilities Maintenance . 74854 Location Cla
21、ss and Changes in Number of Buildings Intended for HumanOccupancy 76855 Concentrations of People in Location Classes 1 and 2 . 77856 Pipeline Service Conversions . 78Table854.1(c) Location Class . 77Chapter VI Corrosion Control860 Corrosion Control . 79861 Scope . 79862 External Corrosion Control .
22、79863 Internal Corrosion Control . 82864 Pipelines in Arctic Environments . 84865 Pipelines in High-Temperature Service . 85866 Stress Corrosion and Other Phenomena 85867 Records . 86Chapter VII Miscellaneous870 Miscellaneous . 87871 Odorization . 87872 Liquefied Petroleum Gas (LPG) Systems 87873 Pi
23、pelines on Private Rights-of-Way of Electric Transmission Lines . 88Chapter VIII Offshore Gas TransmissionA800 Offshore Gas Transmission . 89A801 General 89A802 Scope and Intent . 89A803 Offshore Gas Transmission Definitions . 89A811 Qualification of Materials and Equipment 90A814 Material Specifica
24、tions . 90ivCopyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A817 Conditions for the Reuse and Requalification of Pipe . 90A820 Welding Offshore Pipelines 91A821 General 91A823 Qualification of Proc
25、edures and Welders . 91A825 Stress Relieving 91A826 Welding and Inspection Tests 91A830 Piping System Components and Fabrication Details . 92A831 Piping System Components 92A832 Expansion and Flexibility 92A834 Supports and Anchorage for Exposed Piping . 92A835 Anchorage for Buried Piping . 92A840 D
26、esign, Installation, and Testing . 92A841 Design Considerations . 92A842 Strength Considerations 93A843 Compressor Stations . 96A844 On-Bottom Stability 97A846 Valves . 98A847 Testing 98A850 Operating and Maintenance Procedures Affecting the Safety of GasTransmission Facilities . 99A851 Pipeline Mai
27、ntenance 99A854 Location Class . 100A860 Corrosion Control of Offshore Pipelines 100A861 Scope . 100A862 External Corrosion Control . 100A863 Internal Corrosion Control . 102TableA842.22 Design Factors for Offshore Pipelines, Platform Piping, and PipelineRisers . 94Chapter IX Sour Gas ServiceB800 So
28、ur Gas Service . 103B801 General 103B802 Scope and Intent . 103B803 Sour Gas Terms and Definitions 103B813 Marking . 104B814 Material Specifications . 104B820 Welding Sour Gas Pipelines 104B821 General 104B822 Preparation for Welding . 104B823 Qualifications of Procedures and Welders 104B824 Preheat
29、ing . 104B825 Stress Relieving 104B826 Welding and Inspection Tests 105B830 Piping System Components and Fabrication Details . 105B831 Piping System Components 105B840 Design, Installation, and Testing . 105B841 Steel Pipe 105B842 Other Materials 106B843 Compressor Stations . 106B844 Pipe-Type and B
30、ottle-Type Holders 106B850 Additional Operating and Maintenance Considerations Affecting theSafety of Sour Gas Pipelines . 106B851 Pipeline Maintenance 107B855 Concentrations of People in Location Classes 1 and 2 . 107B860 Corrosion Control of Sour Gas Pipelines 107B861 General 107vCopyright ASME In
31、ternational Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-B862 External Corrosion Control . 107B863 Internal Corrosion Control . 108B866 Stress Corrosion and Other Phenomena 108AppendicesA References . 109B Numbers and Subje
32、cts of Standards and Specifications That Appear inAppendix A . 112C Publications That Do Not Appear in the Code or Appendix A 113D Specified Minimum Yield Strength for Steel Pipe Commonly Used inPiping Systems 115E Flexibility and Stress Intensification Factors . 117F Extruded Headers and Welded Bra
33、nch Connections 123G Testing of Welders Limited to Work on Lines Operating at HoopStresses of Less Than 20% of the Specified Minimum Yield Strength 128H Flattening Test for Pipe 129I End Preparations for Buttwelding 130J Commonly Used Conversion Factors . 137K Criteria for Cathodic Protection 141L D
34、etermination of Remaining Strength of Corroded Pipe . 143M Gas Leakage Control Criteria . 144N Recommended Practice for Hydrostatic Testing of Pipelines in Place 151O Preparation of Technical Inquiries to the ASME Code for Pressure Piping,B31 . 153P Nomenclature for Figures 154Q Scope Diagrams . 155
35、R Estimating Strain in Dents . 158Index 160viCopyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-FOREWORDThe need for a national code for pressure piping became increasingly evident from 1915 to1925. T
36、o meet this need, the American Engineering Standards Committee (later changed to theAmerican Standards Association, now the American National Standards Institute) initiated ProjectB31 in March 1926 at the request of the American Society of Mechanical Engineers and withthat Society as sole sponsor. A
37、fter several years of work by Sectional Committee B31 and itssubcommittees, a first Edition was published in 1935 as an American Tentative Standard Codefor Pressure Piping.A revision of the original tentative standard began in 1937. Several more years of effort weregiven to securing uniformity among
38、 sections, eliminating divergent requirements and discrepan-cies, keeping the Code abreast of current developments in welding technique, calculating stresscomputations, and including reference to new dimensional and material standards. During thisperiod, a new section added on refrigeration piping w
39、as prepared in cooperation with theAmerican Society of Refrigeration Engineers and complemented the American Standard Codefor Mechanical Refrigeration. This work culminated in the 1942 American Standard Code forPressure Piping.Supplements 1 and 2 of the 1942 Code, which appeared in 1944 and 1947, re
40、spectively, introducednew dimensional and material standards, a new formula for pipe wall thickness, and morecomprehensive requirements for instrument and control piping. Shortly after the 1942 Code wasissued, procedures were established for handling inquires requiring explanation or interpretationo
41、f Code requirements and for publishing such inquiries and answers in Mechanical Engineeringfor the information of all concerned.By 1948, continuing increases in the severity of service conditions combined with the develop-ment of new materials and designs to meet these higher requirements warranted
42、more extensivechanges in the Code than could be provided from supplements alone. The decision was reachedby the American Standards Association and the sponsor to reorganize the sectional committeeand its several subcommittees and to invite the various interested bodies to reaffirm their represen-tat
43、ives or to designate new ones.Because of the wide field involved, between 30 and 40 different engineering societies, govern-ment bureaus, trade associations, institutes, and similar organizations have had one or morerepresentatives on the sectional committee, plus a few “members at large” to represe
44、nt generalinterests. Code activities have been subdivided according to the scope of the several sections.General direction of Code activities rested with the Standards Committee officers and an executivecommittee, membership of which consisted principally of Standards Committee officers andsection c
45、hairmen.Following its reorganization in 1948, Standards Committee B31 made an intensive review ofthe 1942 Code that resulted in(a) a general revision and extension of requirements to agree with present day practice(b) the revision of references to existing dimensional standards and material specific
46、ations andthe addition of references to the new ones(c) the clarification of ambiguous or conflicting requirementsA revision was presented for letter ballot vote of Standards Committee B31. Following approvalby this body, the project was approved by the sponsor organization and by the American Stand
47、ardsAssociation. It was finally designated as an American Standard in February 1951, with thedesignation B31.1-1951.Standards Committee B31 at its annual meeting of November 29, 1951, authorized the separatepublication of a section of the Code for Pressure Piping addressing gas transmission and dist
48、ribu-tion piping systems, to be complete with the applicable parts of Section 2, Gas and Air PipingSystems, Section 6, Fabrication Details, and Section 7, Materials Their Specifications andIdentification. The purpose was to provide an integrated document for gas transmission anddistribution piping t
49、hat would not require cross-referencing to other sections of the Code.viiCopyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-The first Edition of this integrated document, known as American Standard Code for PressurePiping, Section 8, Gas Transmission and Distribution Piping Systems, was published in 1952 andconsisted almost
