1、AN AMERICAN NATIONAL STANDARDASME B31.8-2010(Revision of ASME B31.8-2007)Gas Transmission and Distribution Piping SystemsASME Code for Pressure Piping, B31Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from I
2、HS-,-,-INTENTIONALLY LEFT BLANKCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME B31.8-2010(Revision of ASME B31.8-2007)Gas Transmission andDistribution PipingSystemsASME Code for Pressure Pipi
3、ng, B31AN AMERICAN NATIONAL STANDARDCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Date of Issuance: June 1, 2010The next edition of this Code is scheduled for publication in 2012. There will be
4、no addenda issuedto this edition.ASME issues written replies to inquiries concerning interpretations of technical aspects of this Code.The interpretations will be included with this edition. Interpretations are published on the ASME Website under the Committee Pages at http:/cstools.asme.org as they
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10、ies, which precludes the issuance of interpretations by individuals.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.The American Society of Mechanical EngineersThree Park Avenue, New York, NY
11、10016-5990Copyright 2010 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-CONTENTSForeword viiiCommittee Roster . x
12、Introduction . xiiiSummary of Changes xvGeneral Provisions and Definitions801 General . 1802 Scope and Intent 1803 Piping Systems Definitions 2804 Piping Systems Component Definitions 4805 Design, Fabrication, Operation, and Testing Terms andDefinitions . 6806 Quality Assurance 11Chapter I Materials
13、 and Equipment810 Materials and Equipment . 13811 Qualification of Materials and Equipment . 13812 Materials for Use in Low Temperature Applications 14813 Marking 14814 Material Specifications 14815 Equipment Specifications 15816 Transportation of Line Pipe . 15817 Conditions for the Reuse of Pipe 1
14、5Table817.1.3-1 Tensile Testing 16Chapter II Welding820 Welding 18821 General . 18822 Preparation for Welding . 18823 Qualification of Procedures and Welders . 18824 Preheating 19825 Stress Relieving . 19826 Weld Inspection Requirements . 20827 Repair or Removal of Defective Welds in Piping Intended
15、to Operate at Hoop Stress Levels of 20% or More ofthe Specified Minimum Yield Strength 21Chapter III Piping System Components and Fabrication Details830 Piping System Components and Fabrication Details 22831 Piping System Components . 22832 Expansion and Flexibility . 28833 Design for Longitudinal S
16、tress . 29834 Supports and Anchorage for Exposed Piping 32835 Anchorage for Buried Piping 32Tables831.4.2-1 Reinforcement of Welded Branch Connections, SpecialRequirements . 27832.2-1 Thermal Expansion or Contraction of PipingMaterials . 29iiiCopyright ASME International Provided by IHS under licens
17、e with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-832.5-1 Modulus of Elasticity for Carbon and Low AlloySteel . 29Chapter IV Design, Installation, and Testing840 Design, Installation, and Testing . 34841 Steel Pipe . 36842 Other Materials . 48843 Compress
18、or Stations 55844 Pipe-Type and Bottle-Type Holders 58845 Control and Limiting of Gas Pressure 59846 Valves 64847 Vaults 65848 Customers Meters and Regulators 66849 Gas Service Lines . 67Tables841.1.6-1 Basic Design Factor, F . 38841.1.6-2 Design Factors for Steel Pipe Construction . 39841.1.7-1 Lon
19、gitudinal Joint Factor, E . 40841.1.8-1 Temperature Derating Factor, T, for Steel Pipe . 40841.1.11-1 Pipeline Cover Requirements 41841.2.3-1 Pipeline Field Cold Bend Requirements 43841.3.2-1 Test Requirements for Steel Pipelines and Mains toOperate at Hoop Stresses of 30% or More of theSpecified Mi
20、nimum Yield Strength of the Pipe . 47841.3.3-1 Maximum Hoop Stress Permissible During an Air or GasTest 48842.1.1-1 Standard Thickness Selection Table for DuctileIron Pipe . 49842.2.2-1 Wall Thickness and Standard Dimension Ratio forThermoplastic Pipe . 51842.2.3-1 Diameter and Wall Thickness for Re
21、inforcedThermosetting Plastic Pipe 51842.2.9-1 Nominal Values for Coefficients of Thermal Expansionof Thermoplastic Pipe Materials . 53844.3-1 Design Factors, F . 58844.3-2 Minimum Clearance Between Containers and FencedBoundaries . 58845.2.2-1 Maximum Allowable Operating Pressure for Steel orPlasti
22、c Pipelines or Mains . 60845.2.3-1 Maximum Allowable Operating Pressure for PipelinesOperating at 100 psig (690 kPa) or More . 60845.2.3-2 Maximum Allowable Operating Pressure for PipelinesOperating at Less Than 100 psig (690 kPa) 61Chapter V Operating and Maintenance Procedures850 Operating and Mai
23、ntenance Procedures Affecting theSafety of Gas Transmission and DistributionFacilities 71851 Pipeline Maintenance . 73852 Distribution Piping Maintenance 79853 Miscellaneous Facilities Maintenance 82854 Location Class and Changes in Number of BuildingsIntended for Human Occupancy 84855 Pipeline Serv
24、ice Conversions 86856 Odorization . 86857 Uprating 87ivCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Figure851.4.1-1 Allowable Ripple Heights . 75Table851.4.4-1 Wall Thickness for Unlikely Occur
25、rence of Burn-Through 77854.1-1 Location Class 85857.4-1 Wall Thickness Allowance for Uprating a Ductile IronHigh-Pressure Main or System 89Chapter VI Corrosion Control860 Corrosion Control General 90861 External Corrosion Control for Steel Pipelines 91862 Cathodic Protection Criteria . 93863 Operat
26、ion and Maintenance of Cathodic ProtectionSystems 93864 Internal Corrosion Control 93865 Steel Pipelines in Arctic Environments . 94866 Steel Pipelines in High-Temperature Service . 95867 Stress Corrosion and Other Phenomena 96868 Cast Iron, Wrought Iron, Ductile Iron, and Other MetallicPipelines .
27、96Chapter VII Intentionally Left BlankChapter VIII Offshore Gas TransmissionA800 Offshore Gas Transmission 98A801 General . 98A802 Scope and Intent 98A803 Offshore Gas Transmission Terms and Definitions 98A811 Qualification of Materials and Equipment . 99A814 Material Specifications 99A817 Condition
28、s for the Reuse and Requalification of Pipe 100A820 Welding Offshore Pipelines 100A821 General . 100A823 Qualification of Procedures and Welders . 100A825 Stress Relieving . 100A826 Inspection of Welds . 101A830 Piping System Components and Fabrication Details 101A831 Piping System Components . 101A
29、832 Expansion and Flexibility . 101A834 Supports and Anchorage for Exposed Piping 101A835 Anchorage for Buried Piping 101A840 Design, Installation, and Testing . 101A841 Design Considerations 102A842 Strength Considerations . 103A843 Compressor Stations 106A844 On-Bottom Stability . 106A846 Valves 1
30、07A847 Testing . 108A850 Operating and Maintenance Procedures Affecting theSafety of Gas Transmission Facilities 108A851 Pipeline Maintenance . 109A854 Location Class 110A860 Corrosion Control of Offshore Pipelines 110A861 External Corrosion Control 110A862 Cathodic Protection Criteria . 111A864 Int
31、ernal Corrosion Control 112vCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-TableA842.2.2-1 Design Factors for Offshore Pipelines, PlatformPiping, and Pipeline Risers 104Chapter IX Sour Gas Servic
32、eB800 Sour Gas Service 113B801 General . 113B802 Scope and Intent 113B803 Sour Gas Terms and Definitions . 113B813 Marking 114B814 Material Specifications 114B820 Welding Sour Gas Pipelines . 114B821 General . 114B822 Preparation for Welding . 114B823 Qualification of Procedures and Welders . 114B82
33、4 Preheating 114B825 Stress Relieving . 115B826 Welding and Inspection Tests 115B830 Piping System Components and Fabrication Details 115B831 Piping System Components . 115B840 Design, Installation, and Testing . 115B841 Steel Pipe . 115B842 Other Materials . 116B843 Compressor Stations 116B844 Pipe
34、-Type and Bottle-Type Holders 116B850 Additional Operating and MaintenanceConsiderations Affecting the Safety of Sour GasPipelines . 116B851 Pipeline Maintenance . 117B854 Location Class and Changes in Number of BuildingsIntended for Human Occupancy 118B860 Corrosion Control of Sour Gas Pipelines .
35、118B861 External Corrosion Control for Steel Pipelines 118B864 Internal Corrosion Control 118B867 Stress Corrosion and Other Phenomena 119TablesB850.1-1 100-ppm ROE . 117B850.1-2 500-ppm ROE . 117B850.1-3 Metric Example for 100-ppm ROE . 117B850.1-4 Metric Example for 500-ppm ROE . 118AppendicesMand
36、atory Appendix A References 121Mandatory Appendix B Numbers and Subjects of Standards and SpecificationsThat Appear in Mandatory Appendix A . 124Nonmandatory Appendix C Publications That Do Not Appear in the Code orMandatory Appendix A 125Mandatory Appendix D Specified Minimum Yield Strength for Ste
37、el PipeCommonly Used in Piping Systems . 128Mandatory Appendix E Flexibility and Stress Intensification Factors 130Mandatory Appendix F Extruded Headers and Welded Branch Connections 136Mandatory Appendix G Testing of Welders Limited to Work on Lines Operatingat Hoop Stresses of Less Than 20% of the
38、 SpecifiedMinimum Yield Strength 144Mandatory Appendix H Flattening Test for Pipe . 145Mandatory Appendix I End Preparations for Buttwelding . 146Nonmandatory Appendix J Commonly Used Conversion Factors 155viCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reprod
39、uction or networking permitted without license from IHS-,-,-Mandatory Appendix K Criteria for Cathodic Protection . 159Nonmandatory Appendix L Determination of Remaining Strength of CorrodedPipe 161Nonmandatory Appendix M Gas Leakage Control Criteria 162Nonmandatory Appendix N Recommended Practice f
40、or Hydrostatic Testing ofPipelines in Place . 169Nonmandatory Appendix O Preparation of Technical Inquiries . 171Nonmandatory Appendix P Nomenclature for Figures . 172Mandatory Appendix Q Scope Diagrams . 173Nonmandatory Appendix R Estimating Strain in Dents 176Index 177viiCopyright ASME Internation
41、al Provided by IHS under license with ASME Not 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. To meet this need, the American Engineering Standards Committee (later
42、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. After several years of work by Sectional Committee B31 and itssubcommit
43、tees, 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 sections, eliminating divergent requirements and discrepan-cies, keep
44、ing 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 was prepared in cooperation with theAmerican Society of Refrigeration E
45、ngineers 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, respectively, introducednew dimensional and material standards, a new fo
46、rmula 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 interpretationof Code requirements and for publishing such inquiries and answers in M
47、echanical 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 more extensivechanges in the Code than could be provided from suppleme
48、nts 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-tatives or to designate new ones.Because of the wide field involved, betw
49、een 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 represent generalinterests. Code activities have been subdivided according to the scope of the several section
