Pipeline
Transport ation
Systems for L iquids
and Slurries
ASME Code for Pressure Piping , B31
AN INTERNATIONAL PIPING CODE
®
(R evision of ASME B31.4-2016)
Pipel ine
T r a nspor ta tion
Sy stems for Liquids
a nd Sl ur r ies
A SME Code for Pr essur e Piping, B31
A N INT ERNA T IONA L PIPING CODE
®
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Foreword . .. . .. . .. .. . .. . .. .. . .. . .. . .. . .. .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. vii
CommitteeRoster . .. .. . .. . .. .. . .. . .. . .. . .. .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. ix
Correspondence With the B31 Committee . . . .. . . .. . . .. . . .. . . . .. . . .. . . .. . . .. . . .. . . . .. . . .. . x i Introduction . .. .. . .. . .. . .. . .. . .. .. . .. . .. .. . .. . .. . .. . .. . .. .. . .. . .. .. . .. . .. . .. . .. .. . x iii SummaryofChang es . . .. . . .. . . .. . . .. . . .. . . .. . . .. . .. . . .. . . .. . . .. . . .. . .. . . .. . . .. . . .. . x v ChapterI ScopeandDefinitions .. . . .. . . .. . .. . . .. . . .. . .. . . .. . . .. . . .. . . .. . .. . . .. . 1
400 General Statements .. . .. . . .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . . .. . .. . . .. . .. . 1
ChapterII Desig n . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . 11
401 Loads .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . 11
402 CalculationofStresses . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 13
403 CriteriaforPipelines . .. . .. . .. . . .. . .. . .. . . .. . .. . .. . . .. . .. . .. . . .. . .. . .. . 18
404 CriteriaforFitting s, A ssemblies, andOtherComponents(A lternatively,Criteriafor Components) . . .. . . .. . . .. . . . .. . . .. . . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . 24
ChapterIII Materials .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 37
423 Materials— GeneralRequirements . . . . .. . . .. . . .. . . .. . . . .. . . .. . . 37
425 MaterialsAppliedto Miscellaneous Parts .. . . .. . . .. . . .. . . .. . . .. . . 38
ChapterIV DimensionalRequirements . .. . .. . . .. . .. . .. . . .. . .. . .. . . .. . .. . .. . . .. . .. . 41
426 DimensionalRequirements forStandardandNonstandardPipingComponents . . . 41
ChapterV Construction,Welding ,andA ssembly .. . . .. . . .. . . . .. . .. . . .. . . .. . . . .. . . .. . 43
434 Construction .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . 43
435 A ssemblyofPipingComponents .. . .. . .. .. . .. . .. . .. . .. .. . .. . .. . .. . .. . .. .. . 55
ChapterVI Inspectionand Testing . . .. . . .. . . .. . . .. . . . .. . . .. . . .. . . .. . . .. . . . .. . . .. . 57
436 Inspection .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. . .. 57
437 Testing .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. .. . 58
ChapterVII Operationand MaintenanceProcedures . . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 61
450 OperationandMaintenance Procedures A ffectingthe SafetyofLiquidandSlurry TransportationPipingSystems . . .. . .. .. . .. . .. . .. . .. . .. .. . .. . .. . .. . .. .. . 61
451 Pipeline OperationandMaintenance .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. . .. . .. 62
452 Pump Station, Terminal,andStorag eFacilities OperationandMaintenance .. . . .. . . .. . 71
453 CorrosionControl . . .. . .. . . .. . . .. . .. . . .. . . .. . .. . . .. . .. . . .. . . .. . .. . . .. . 71
454 Emerg encyPlan . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . 71
455 Records . . .. . . .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . .. . . .. . . .. . . .. . . .. . . .. . 72
456 Q ualifyingaPipingSystemforaHig herOperatingPressure . .. . .. . .. . .. . .. . . .. .. . 72
457 A bandoningaPipingSystem . .. . . . .. . . .. . . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . 73
ChapterVIII Corrosion Control . . . .. . . .. . . .. . .. . . .. . . .. . .. . . .. . . .. . . .. . . .. . .. . . .. . 74
460 General .. . .. .. . .. . .. . .. . .. .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. 74
461 Ex ternal CorrosionControl forBuriedorSubmerg edPipelines .. . .. . .. . .. . .. . .. .. . 74
462 InternalCorrosionControl . . .. . .. . . .. . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . 77
465 Pipelines inHig h-Temperature Service . . . .. . . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . 79
466 Ex ternal CorrosionControl forThermallyInsulatedPipelines .. . .. . .. . .. . .. . .. . .. . 80
467 Stress CorrosionandOtherPhenomena . .. . . .. . . . .. . . . .. . . . .. . . .. . . . .. . 81
468 Records . . .. . . .. . .. . . .. . . .. . . .. . . .. . . .. . .. . . . .. . .. . . .. . . .. . . .. . . .. . 81
ChapterIX Offshore LiquidPipelineSystems . . .. . . . .. . . . .. . . . .. . . .. . . . .. . . . .. . . . .. . 82
A 400 General Statements .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . . .. . .. . . .. . .. . . .. . .. . 82
A 401 Loads .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 83
A 402 CalculationofStresses . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 85
A 403 CriteriaforPipelines . .. . .. . .. . .. . . .. . .. . . .. . .. . .. . .. . . .. . .. . . .. . .. . .. . 89
A 404 CriteriaforFitting s, A ssemblies, andOtherComponents(A lternatively,Criteriafor Components) . .. . . . .. . . . .. . . .. . . .. . . . .. . . .. . . .. . . . .. . . .. . . .. . . . .. . 89
A 405 Pipe . . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . . .. . .. . .. . .. . 90
A 406 OtherDesig nConsiderations . . . . .. . . .. . . . .. . . . .. . . .. . . . .. . . .. . . . .. . . . .. . 90
A 423 Materials— GeneralRequirements . . . . .. . . .. . . .. . . .. . . .. . . .. . . 91
A 434 Construction .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . 91
A 436 Inspection .. . .. . .. .. . .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . 92
A 437 Testing .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 93
A 450 OperationandMaintenance Procedures A ffectingthe SafetyofLiquidandSlurry TransportationPipingSystems . . .. . .. .. . .. . .. . .. . .. . .. .. . .. . .. . .. . .. .. . 93
A 451 Pipeline OperationandMaintenance .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. . .. .. . 93
A 452 Pump Station, Terminal,andStorag eFacilities OperationandMaintenance .. . . .. . . .. . 95
A 454 Emerg encyPlan . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . 95
A 460 General .. . .. . .. .. . .. . .. . .. .. . .. . .. .. . .. . .. . .. .. . .. . .. .. . .. . .. . .. .. . 95
A 461 Ex ternal CorrosionControl forBuriedorSubmerg edPipelines .. . .. . .. . .. .. . . .. .. . 95
A 463 Ex ternal CorrosionControl forPipelines Ex posedtoA tmosphere . . . .. . . . .. . . . .. . 96
ChapterX Carbon Diox ide PipelineSystems . . . . .. . . .. . . . .. . . . .. . . . .. . . .. . . . .. . 97
B400 General Statements .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . . .. . .. . . .. . .. . . .. . .. . 97
B423 Materials— GeneralRequirements . . . . .. . . .. . . .. . . .. . . .. . . .. . . 97
B434 Construction .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . 97
B437 Testing .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 97
B451 Pipeline OperationandMaintenance .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. . .. .. . 98
B454 Emerg encyPlan . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . 98
ChapterX I SlurryPipelineSystems .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . 99
C400 General Statements .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . . .. . .. . . .. . .. . . .. . .. . 99
C401 Loads .. . .. . .. . .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 99
C403 CriteriaforPipelines . .. . .. . .. . .. . . .. . .. . . .. . .. . .. . .. . . .. . .. . . .. . .. . .. . 99
C404 CriteriaforFitting s, A ssemblies, andOtherComponents(A lternatively,Criteriafor Components) . .. . . . .. . . . .. . . .. . . .. . . . .. . . .. . . .. . . . .. . . .. . . .. . . . .. . 100
C423 Materials— GeneralRequirements . . . . .. . . .. . . .. . . .. . . .. . . .. . . 100
C426 Dimensional Requirements forStandardandNonstandardPipingComponents . . . 100
C434 Construction .. . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . . .. . .. . .. . .. . .. . .. . .. . 100
C437 Testing .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 101
C451 Pipeline OperationandMaintenance .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. . .. .. . 102
C454 Emerg encyPlan . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . . .. . . . .. . . .. . . .. . . . .. . 102
C461 Ex ternal CorrosionControl forBuriedorSubmerg edPipelines .. . .. . .. . .. . .. . .. .. . 102
C468 Records . . .. . . .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . .. . . .. . . .. . . .. . . .. . . .. . 102
MandatoryA ppendix I ReferencedStandards .. . . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . .. . . .. . 103
NonmandatoryA ppendices A SubmittalofTechnicalInquiries tothe B31 PressurePipingCommittee . . . 107
B Publications ThatDoNotA ppearintheCode orMandatoryA ppendixI butMayBe of Informational Benefit . . . .. . . .. . . .. . . . .. . . . .. . . . .. . . . .. . . . .. . . . .. . . 108
Index . .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . 109
Fig ures 400.1.1-1 Diag ramShowingScope ofA SMEB31.4Ex cludingCarbonDiox ide Pipeline Systems (See Fig ure 400.1.1-2) .. . . . .. . . .. . . . .. . . .. . . . .. . . . .. . . . .. . . . .. . . .. . . .. . . 3
400.1.1-2 Diag ramShowingScope ofA SMEB31.4forCarbonDiox ide Pipeline Systems . . . 4
400.1.1-3 Diag ramShowingScope ofA SMEB31.4forSlurryPipeline Systems . .. . . .. . . .. . . .. . 5
404.3.3.1-1 ReinforcedEx trudedOutlets . . . .. . . . .. . . .. . . . .. . . .. . . . .. . . . .. . . . .. . . 27
404.3.4-1 WeldingDetailsforOpening sWith Complete EncirclementTypesofReinforcement . . . . 30
404.3.4-2 WeldingDetailsforOpening sWith Localized-Type Reinforcement. . . 31
404.3.4-3 WeldingDetailsforOpening sWithoutReinforcementOtherThanThatinHeaderandBranch Walls . . .. . . .. . .. . .. . .. . . .. . . .. . .. . .. . .. . . .. . .. . . .. . .. . .. . . .. . .. . 32
404.3.5-1 ReinforcementofBranch Connections .. . .. .. . .. . .. . .. .. . .. . .. . .. .. . .. . .. . .. 33
434.8.6-1 A cceptable ButtWeldedJointDesig nforEqual WallThicknesses .. . . .. . . .. . . 48
434.8.6-2 A cceptable ButtWeldedJointDesig nforUnequal Wall Thicknesses . . . .. . . 49
434.8.6-3 RecommendedA ttachmentDetails ofFlang es .. . . . .. . . . .. . . . .. . . .. . . . .. . . . .. . 50
451.6.2.2-1 Type IInteraction .. . .. . .. . . .. . .. . .. . . .. . .. . .. . .. . . .. . .. . .. . . .. . .. . .. . 65
451.6.2.2-2 Type II Interaction . . . .. . . .. . . . .. . . .. . . . .. . . .. . . . .. . . .. . . . .. . . .. . . . .. . 65
Tables 402.1-1 Flex ibilityFactor, k, andStress IntensificationFactor, i . .. . . .. . . .. . . 14
403.2.1-1 WeldJointFactors A pplicable to CommonPipe Specifications . . . 19
403.3.1-1 A llow ableV alues forPipeline SystemStresses . . .. . .. .. . .. . .. . .. .. . .. . .. . .. . .. 20
404.3.4-1 Desig nCriteriaforWeldedBranch Connections . .. . .. .. . .. . .. . .. .. . .. . .. . .. . .. 32
423.1-1 MaterialStandardsandSpecifications . . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . .. . 39
426.1-1 DimensionalStandards . . . . .. . . .. . . . .. . . .. . . . .. . . .. . . . .. . . . .. . . .. . . . .. . 42
434.6-1 MinimumCoverforBuriedPipelines . . .. . . . .. . . .. . . . .. . . . .. . . .. . . . .. . . 45
451.6.2.9-1 A cceptable Pipeline RepairMethods (Nonindented, Nonw rinkled, andNonbuckled Pipe) .. . . .. . . .. . .. . . .. . . .. . .. . . .. . . .. . . .. . . .. . .. . . .. . . .. . .. . . .. . 69
451.6.2.9-2 A cceptablePipelineRepairMethodsforDents,Buckles,Ripples,Wrinkles,LeakingCoupling s, andDefectivePriorRepairs .. . . .. . .. . .. . . .. . .. . .. . . .. . .. . .. . . .. . .. . .. . 70
A 402.3.2-1 Desig nFactors forOffshore Pipeline Systems . . . . .. . . .. . . .. . . .. . . .. . . 87
C426.1-2 Dimensional Standards NotA pplicable forSlurryPipingSystems FromTable 426.1-1 . . . 101
Theneedforanationalcodeforpressurepipingbecameincreasing lyevidentfrom1915to1925.Tomeetthisneed,the
AmericanEngineeringStandards Committee [laterchangedto theAmericanStandards Association(A SA)] initiated
ProjectB31 inMarch 1926 atthe requestofThe AmericanSocietyofMechanical Engineers (ASME), andw ith that
society as sole sponsor. After several years’ workbySectional Committee B31 andits subcommittees, a first
editionw as publishedin1935 as anA mericanTentativeStandardCode forPressure Piping .
Arevisionofthe orig inal tentativestandardwas beg unin1937.Severalmore years’ effortwas g iventosecuring
uniformitybetw eensectionsandtoeliminatingdiverg entrequirementsanddiscrepancies,aswellastokeepingthecode
abreastofcurrentdevelopmentsinweldingtechnique,stress computations, andreferences tonewdimensionaland
materialstandards.Duringthisperiod,anewsectionw asaddedonrefrig erationpiping ,preparedincooperationwith
TheAmericanSocietyofRefrig erationEng ineers(A SRE)andcomplementingtheA mericanStandardCodeforMechanical
Refrig eration. This w orkculminatedinthe 1942A mericanStandardCode forPressure Piping .
Supplements1and2ofthe1942code,w hichappearedin1944and1947,respectively,introducednewdimensional
andmaterialstandards,anewformulaforpipew allthickness,andmorecomprehensiverequirementsforinstrumentand
controlpiping .Shortlyafterthe1942codewasissued,procedureswereestablishedforhandlinginquiriesthatrequire
ex planationorinterpretationofcoderequirements,andforpublishingsuchinquiriesandanswersinMechanicalEngi-
nee ring forthe informationofall concerned.
Continuingincreasesintheseverityofserviceconditions,withconcurrentdevelopmentsofnewmaterialsanddesig ns
equaltomeetingthesehig herrequirements,hadpointedtotheneedby1948formoreex tensivechang esinthecodethan
couldbe providedby supplements alone. The decisionw as reachedbyASAandASME toreorganize the Sectional
Committeeanditsseveralsubcommittees,andtoinvitethevariousinterestedbodiestoreaffirmtheirrepresentatives
ortodesig natenewones.Followingitsreorg anization,SectionalCommitteeB31madeanintensivereviewofthe1942
code,andarevisedcodewasapprovedandpublishedinFebruary1951withthedesig nationASAB31.1-1951,which
included
(a) ag eneral revisionandex tensionofrequirementsto ag ree w ithpractices currentatthetime
(b) revisionofreferences toex istingdimensionalstandards andmaterialspecifications,andthe additionofnew
references
(c) clarificationofambig uous orconflictingrequirements
SupplementNo.1toASAB31.1wasapprovedandpublishedin1953asA SAB31.1a-1953.ThisSupplementandother
approvedrevisions were includedinaneweditionpublishedin1955 with thedesig nationA SAB31.1-1955.
AreviewbyB31Ex ecutiveandSectionalCommitteesin1955resultedinadecisiontodevelopandpublishindustry
sectionsasseparatecodedocumentsoftheAmericanStandardB31CodeforPressurePiping .A SAB31.4-1959wasthe
firstseparatecodedocumentforOilTransportationPipingSystemsandsupersededthatpartofSection3ofA SAB31.1-
1955coveringoiltransportationpipingsystems.In1966,B31.4w asrevisedtoex pandcoverag eonwelding ,inspection,
andtesting ,andtoaddnewchapterscoveringconstructionrequirementsandoperationandmaintenanceprocedures
affectingthesafetyofthepipingsystems.Thisrevisionwaspublishedwiththedesig nationUSA SB31.4-1966,Liquid
PetroleumTransportationPipingSystems,sinceA SAwasreconstitutedastheUnitedStatesofA mericaStandardsInsti-
tute(USA SI) in1966.
USA SIchang editsname,effectiveOctober6,1969,totheA mericanNationalStandardsInstitute,Inc.(A NSI),andUSA S
B31.4-1966wasredesig natedasA NSIB31.4-1966.TheB31SectionalCommitteewasredesig natedasA mericanNational
Standards Committee B31Code forPressurePiping , and, because ofthe wide fieldinvolved,morethan40different
eng ineeringsocieties,g overnmentbureaus,tradeassociations,institutes,andthelikehadoneormorerepresentativeson
StandardsCommitteeB31,plusafew“IndividualMembers”torepresentg eneralinterests.Codeactivitiesweresubdi-
videdaccordingtothe scope ofthe several sections,andg eneraldirectionofCode activities restedwithStandards
CommitteeB31officersandanEx ecutiveCommitteewhosemembershipconsistedprincipallyofStandardsCommittee
officers andchairmenofthe SectionandTechnical Specialists Committees.
The A NSIB31.4-1966 Code was revisedandpublishedin1971 w ith the desig nationA NSI B31.4-1971.
The A NSIB31.4-1971 Code was revisedandpublishedin1974 w ith the desig nationA NSI B31.4-1974.
w ith thedesig nationA NSI/A SMEB31.4-1979.
Follow ingpublicationofthe1979edition,theB31.4SectionCommitteebeg anworkonex pandingthescopeoftheCode
tocoverrequirementsforthetransportationofliquidalcohols.Referencestoex istingdimensionalstandardsandmate-
rialspecificationsw ererevised,andnewreferenceswereadded.Otherclarifyingandeditorialrevisionsweremadein
ordertoimprovethetex t.Theserevisionsledtothepublicationoftw oaddendatoANSI/A SMEB31.4.A ddenda“ b”w as
approvedandpublishedin1981asANSI/A SMEB31.4b-1981.A ddenda“ c”wasapprovedandpublishedin1986asANSI/
ASMEB31.4c-1986.
The 1986editionofANSI/A SMEB31.4 includedthe two previouslypublishedaddendato the 1979 edition.
Follow ingpublicationofthe1986 edition,clarifyingandeditorialrevisionsw eremade toimprovethe tex t.A ddi-
tionally,referencestoex istingstandardsandmaterialspecificationswererevised,andnewreferenceswereadded.These
revisionsledtothepublicationofanaddendathatw asapprovedandpublishedin1987asA SME/A NSIB31.4a-1987.
The 1989editionofASME/A NSIB31.4 includedthe previouslypublishedaddendatothe 1986 edition.
Follow ingpublicationofthe1989edition,clarifyingrevisionsweremadetoimprovethetex t.A dditionally,references
toex istingstandardsandmaterialspecificationsw ererevisedandupdated.Theserevisionsledtothepublicationofan
addendathatwas approvedandpublishedin1991as A SMEB31.4a-1991.
The1992editionofA SMEB31.4includedthepreviouslypublishedaddendatothe1989editionandarevisiontovalve
maintenance.The1992 editionwas approvedbyA NSI onDecember15, 1992,anddesig natedas A SMEB31.4-1992
edition.
The1998editionofA SMEB31.4includedthepreviouslypublishedaddendatothe1992edition.Alsoincludedinthe
1998editionwereotherrevisionsandtheadditionofChapterIX,OffshoreLiquidPipelineSystems.The1998editionw as
approvedbyANSI onNovember11, 1998,anddesig natedas ASMEB31.4-1998 edition.
The2002editionofA SMEB31.4includedthepreviouslypublishedaddendatothe1998editionalongw ithrevisionsto
the maintenance sectionandupdatedreferences. The2002 editionw as approvedbyANSI onAugust5, 2002, and
desig natedas A SMEB31.4-2002.
The 2006 editionofASMEB31.4 containedanewrepairsection,alongw ithrevisions to the definitions section,
expansionofmaterialstandards Table 423.1 anddimensional standards Table 426.1, andupdatedreferences. The
2006 editionw as approvedbyA NSIonJanuary5, 2006, anddesig natedas A SMEB31.4-2006.
The2009editionofASMEB31.4containedmajorrevisionstothedefinitionssection;ChapterII,Desig n;andChapter
VIII,CorrosionControl.ThematerialsstandardsTable423.1andreferenceswererevisedandupdated.The2009edition
w as approvedbyA NSIonSeptember14, 2009, anddesig natedas A SME B31.4-2009.
The2012editionofA SMEB31.4containedarevisedscopeandanewchaptertoincorporatetherequirementsfrom
ASMEB31.11,SlurryTransportationPipingSystems.Therewasalsoanewchapterforcarbondiox idepiping ,ex tracting
allofthepreviouscarbondiox ideinformationintoastand-alonechapter.Thedefinitionssectionw asalsorevisedwith
newentries.The2012 editionwas approvedbyA NSIonSeptember14,2012, anddesig natedas ASMEB31.4-2012.
The2016 editionofA SMEB31.4containedarevisedscope andupdates tothestress sectioninChapterII.Anew
parag raphw asaddedinChapterIIIformaterialrequirementsinlow-temperatureapplications.Inaddition,chang esw ere
includedthroug houttoreferenceminimumwallthicknessrequirementsaspermittedbymanufacturingspecifications.
The2016 editionw as approvedbyA NSIonFebruary22, 2016, anddesig natedas A SMEB31.4-2016.
The 2019 editionofA SMEB31.4 contains arew orkofChapterIXto alig nw ith standardizednumberingofother
chapter s.AnewstandardisreferencedinChapterIItoimprovetheaccuracyofcalculationsthatusestressintensification
andflex ibilityfactors.Updatestothetex tandtableinChapterVIonallowablerepairswerecompleted.The2019edition
w as approvedbyA NSIonJuly18, 2019,anddesig natedas A SMEB31.4-2019.
Code for Pr essure Piping
(Thefollow ingistherosteroftheCommitteeatthetimeofapprovalofthisCode.)
ST A NDA RDSCOMMIT T EE OFFICERS
J.E.Mey er ,Chair
J.W.Frey,Vic eChair
A.Maslow ski,Sec retary
J.Oh,Sec retary
ST A NDARDSCOMMIT T EE PERSONNEL
R.J.T.A ppleby ,ExxonMobilPipelineCo.
K.C.Bodenhamer ,TRCPipelineServices
R.Bojarc zuk,Ex xonMobilResearchandEng ineeringCo.
M.R.Br az,MRBraz&Associates,PLLC
M.Bur khar t,TheBurkhartGroup,Inc.
R.D.Campbell,BechtelCor p.
J.S.Chin,TransCanadaPipelineU.S.
D.D.Christian,V ictaulic
R.P.Deubler ,BechtEng ineeringCo.,Inc.
D.Diehl,Hexag onPPM
M.Eng elkemier ,Carg ill
W.H.Eskridge,Jr.,WorleyECR
D.J.Fetzner ,BPExplorationA laska,Inc.
P.D.Flenner ,FlennerEng ineeringServices
J.W .Fr ey,JoeW.FreyEng ineeringSer v ices,LLC
D.R.Fr ikken,BechtEng ineeringCo.,Inc.
R.A .Gric huk,S&BEng ineersandConstr uctors,Ltd.
R.W .Haupt,PressurePipingEngineeringA ssociates,Inc.
L.E.Hayden,Jr.,Consultant
G.A .Jolly ,SamshinLtd.
K.Kaplan,Consultant
C.E.Kolovich,QuestInteg rity
A .Maslowski,TheA mericanSocietyofMechanicalEng ineers
W.J.Maur o,A mericanElectricPower
J.E.Meyer ,CDMSmith—IndustrialDivision
T.Monday ,TeamIndustries,Inc.
M.L.Nayyar,NICE
J.Oh,TheAmericanSocietyofMechanicalEng ineers
G.R.Petru,AcapellaEng ineeringServices,LLC
D.Rahoi,CCM2000
R.Reamey,TurnerIndustriesGroup,LLC
M.J.Rosenfeld,Kiefner/A pplus—RTD
J.T.Schmitz,Southw estGasCorp.
S.K.Sinha,LuciusPitkin,Inc.
W.J.Sper ko,SperkoEng ineeringSer v ices,Inc.
J.P.Sw ezy ,Jr.,BoilerCodeTech,LLC
F.W .Tatar,FMGlobal
K.A .Vilminot,Commonw ealthA ssociates,Inc.
J.S.W illis,Pag eSoutherlandPag e,Inc.
B31.4 LIQUID A ND SLURRY PIPING T RA NSPORT A T ION SY ST EMS SECT ION COMMIT T EE
C.E.Kolovich,Chair,QuestInteg rity
W.M.Olson,Vic eChair,GulfInterstateEng ineering
K.Verder ber,Sec retary,TheA mericanSocietyof
MechanicalEng ineers
E.L.Baniak,A mericanPetroleumInstitute
A .Baty ,Paterson&CookeUSALtd.
K.C.Bodenhamer ,TRCPipelineServices
W.M.Cauthen,Tig erEnergySer v ices,Inc.
R.Duran,Chevron
S.P.Gade,GISandSME
T.Gutier rez,BurrowGlobalServ ices,LLC
E.M.Jorr itsma,ShellProjectsandEng ineering
D.B.Kadakia,Consultant
P.W .Klein,BHPBilliton
S.Koetting ,Ex xonMobilPipelineCo.
Y.Li,EnbridgePipelines,Inc.
S.Mc Kenna,Burns&McDonnell
T.P.McMahan,DNVGL
B.Mittelstadt,DynamicRiskA ssessmentsSy stems,Inc.
A .Morton,WilliamsCo.
B.Mumme,KochPipelineCo.
G.Newman,U.S.DepartmentofTransportation
G.R.Petru,AcapellaEng ineeringServices,LLC
T.M.Shie,ShellPipelineCo.,LP
S.Singh,BechtelOil,Gas,andChemicals,Inc.
B.Slater,BPExplorationA laska,Inc.
D.A .Soenjoto,PlainsAllA mericanPipeline
J.C.Spow ar t,BechtelCorp.
L.Sw eeney ,StantecConsulting
W.L.Trimble,Worley Parsons
C.Zimmerman,U.S.DepartmentofTransportation
M.A .Boring ,ContributingMember,DNVGL
A .Esmaeili,ContributingMember,Orig inEnerg y
D.Gilr oy,ContributingMember,BechtelOil,Gas,andChemicals,Inc.
R.D.Lew is,ContributingMember,RosenUSA
D.Moor e,ContributingMember,TroutHydrodynamics,Inc.
R.J.T.Appleby,Exx onMobilPipelineCo.
M.R.Braz,MRBraz&A ssociates,PLLC
M.Burkhart,TheBurkhartGroup,Inc.
R.D.Campbell,BechtelCorp.
D.D.Christian,Victaulic
R.P.Deubler,BechtEng ineeringCo.,Inc.
D.Diehl,Hex ag onPPM
L.E.Hayden,Jr .,Consultant
C.E.Kolov ic h,Q uestIntegrity
W .J.Mauro,AmericanElectricPow er
J.E.Meyer,CDMSmith—IndustrialDiv ision
M.L.Nay yar ,NICE
S.K.Sinha,LuciusPitkin,Inc.
B31 FA BRICA T ION A ND EX A MINAT ION COMMIT T EE
R.D.Campbell,Chair,BechtelCorp.
U.D’Ur so,Sec retary,TheA mericanSocietyofMechanicalEng ineers
D.Bing ham,LosAlamosNationalLabs
B.Boseo,GraycorServices,LLC
M.DeLong ,IHIE&CInternationalCorp.
R.Dur an,Chev ron
R.J.Ferguson,Metallurgist
P.D.Flenner,FlennerEng ineeringServ ices
J.W .Frey ,JoeW.FreyEng ineeringServ ices,LLC
D.R.Frikken,BechtEng ineeringCo.,Inc.
S.Ging r ich,A ECOM
J.Hainsw orth,WRMetallur gical
T.Monday,TeamIndustries,Inc.
A .D.Nalbandian,ThielschEng ineering ,Inc.
R.Reamey,TurnerIndustriesGroup,LLC
R.J.Silvia,ProcessEng ineers&Constructors,Inc.
W .J.Sperko,SperkoEng ineeringServ ices,Inc.
J.P.Swezy,Jr .,BoilerCodeTech,LLC
K.Wu,StellarEnerg ySystems
B31 MAT ERIA LST ECHNICA L COMMIT T EE
R.P.Deubler,Chair,BechtEng ineeringCo.,Inc.
W .H.Eskr idg e,Jr.,Vic eChair,WorleyECR
C.O’Brien,Secretary,TheA mericanSocietyofMechanicalEng ineers
B.Bounds,BechtelCorp.
W .P.Collins,WPCSol,LLC
R.Gric huk,S&BEngineersandConstructors,Ltd.
J.Gundlach,MichiganSeamlessTubeandPipe
A .A .Hassan,PGESCo
L.Hender son,Jr.,ChiyodaInternationalCorp.
C.Henley ,KiewitEng ineeringGr oup,Inc.
G.A .Jolly,SamshinLtd.
C.J.Melo,S&BEng ineersandConstructors,Ltd.
M.L.Nay yar ,NICE
K.Pham,FluorEnterprises,Inc.
D.W.Rahoi,CCM2000
R.A .Schmidt,Canadoil
D.K.Verma,BechtelOilGasandChemicals,Inc.
Z.Djilali,ContributingMember,Sonatrach
B31 MECHA NICA L DESIGN T E CHNICA L COMMIT T EE
J.E.Mey er,Chair,CDMSmith—IndustrialDiv ision
M.Eng elkemier,ViceChair,Carg ill
R.Rahaman,Se c retary,TheA mericanSocietyof
MechanicalEng ineers
G.A .Antaki,BechtEng ineeringCo.,Inc.
D.A .Ar nett,Ex xonMobilResearchandEng ineering
C.BechtIV,BechtEng ineeringCo.,Inc.
R.Bethea,HII—NewportNew sShipbuilding
J.P.Ellenber g er,Consultant
D.J.Fetzner,BPEx plorationAlaska,Inc.
D.Fr aser ,NA SAA mesResearchCenter
J.A .Graziano,Consultant
J.D.Har t,SSD,Inc.
R.W.Haupt,PressurePipingEng ineeringA ssociates,Inc.
B.P.Holbrook,Consultant
R.A .Leishear ,LeishearEngineering ,LLC
G.D.Mayers,A lionScience&Technolog y
T.Q .Mc Cawley,TQMEng ineeringPC
P.Moor e,Burns&McDonnell
A .Paulin,PaulinResearchGroup
R.A .Robleto,KBR
M.J.Rosenfeld,Kiefner/Applus—RTD
T.Sato,JapanPowerEng ineeringandInspectionCorp.
M.Stewart,A ECOM
J.Minichiello,ContributingMember,BechtelNational,Inc.
Genera l . A SMEStandardsaredevelopedandmaintainedw iththeintenttorepresentthe consensusofconcerned
interests.A ssuch,usersofthisCodemayinteractwiththeCommitteebyrequestinginterpretations,proposingrevisions
oracase, andattendingCommitteemeeting s.Correspondenceshouldbeaddressedto:
Secretary,B31 Standards Committee
TheA mericanSocietyofMechanicalEng ineers
TwoParkA venue
NewYork, NY10016-5990
http://g o.asme.org /Inquiry
Pr oposingRev isions. RevisionsaremadeperiodicallytotheCodetoincorporatechang esthatappearnecessaryor
desirable, as demonstratedby the experience gainedfromthe applicationofthe Code.Approv edrevisions w ill be
publishedperiodically.
TheCommitteewelcomesproposalsforrevisionstothisCode.Suchproposalsshouldbeasspecificaspossible,citing
theparag raphnumber(s),theproposedwording ,andadetaileddescriptionofthereasonsfortheproposal,includingany
pertinentdocumentation.
Pr oposingaCase. Casesmaybeissuedtoprovidealternativeruleswhenjustified,topermitearlyimplementationof
anapprovedrevisionwhentheneedisurg ent,ortoproviderulesnotcoveredbyex istingprovisions.Casesareeffective
immediatelyuponA SMEapproval andshall be postedonthe A SMECommittee web pag e.
RequestsforCasesshallprovideaStatementofNeedandBackg roundInformation.Therequestshouldidentifythe
Codeandtheparag raph,fig ure,ortablenumber(s),andbew rittenasaQuestionandReplyinthesameformatasex isting
Cases.RequestsforCasesshouldalsoindicatetheapplicableedition(s)oftheCodetowhichtheproposedCaseapplies.
Inter preta tions. Uponrequest,theB31StandardsCommitteew illrenderaninterpretationofanyrequirementofthe
Code.Interpretationscanonlyberenderedinresponsetoaw rittenrequestsenttotheSecretaryoftheB31Standards
Committee.
Requests forinterpretationshouldpreferablybe submittedthroug htheonlineInterpretationSubmittalForm.The
formisaccessibleathttp://g o.asme.org /InterpretationRequest.Uponsubmittaloftheform,theInquirerwillreceivean
automatice-mail confirmingreceipt.
IftheInquirerisunabletousetheonlineform,he/shemaymailtherequesttotheSecretaryoftheB31Standards
Committeeattheaboveaddress.Therequestforaninterpretationshouldbeclearandunambig uous.Itisfurtherrec-
ommendedthatthe Inquirersubmithis/herrequestinthe followingformat:
Subject: Citetheapplicableparag raphnumber(s)andthetopicoftheinquiryinoneortwow ords.
Edition: Cite theapplicableeditionofthe Code forwhich the interpretationis beingrequested.
Q uestion: Phrasethequestionasarequestforaninterpretationofaspecificrequirementsuitablefor
g eneralunderstandinganduse,notasarequestforanapprovalofaproprietarydesig nor
situation.Pleaseprovideacondensedandprecisequestion,composedinsuchaw aythata
“yes”or“ no”replyis acceptable.
ProposedReply(ies): Provideaproposedreply(ies) intheformof“Yes”or“No,”w ithex planationas needed.If
enteringreplies tomore thanone question,pleasenumberthe questions andreplies.
Backg roundInformation: ProvidetheCommitteew ithanybackg roundinformationthatw illassisttheCommitteein
understandingtheinquiry.TheInquirermayalsoincludeanyplansordrawing sthatare
necessarytoex plainthequestion;however,theyshouldnotcontainproprietarynamesor
information.
RequeststhatarenotintheformatdescribedabovemayberewrittenintheappropriateformatbytheCommitteeprior
tobeinganswered,whichmay inadvertentlychang ethe intentofthe orig inalrequest.
thattheInquirershouldseekassistance,theinquiryw illbereturnedw iththerecommendationthatsuchassistancebe
obtained.
A SMEproceduresprovideforreconsiderationofanyinterpretationw henorifadditionalinformationthatmig htaffect
aninterpretat ionis av ailable. Further, persons aggriev edby aninterpretat ionmayappeal to the cognizantASME
CommitteeorSubcommittee.A SMEdoesnot“ approve,”“certify,”“ rate,”or“ endorse”anyitem,construction,proprietary
device,oractivity.
A ttendingCommitteeMeetings. TheB31StandardsCommitteereg ularlyholdsmeeting sand/ortelephoneconfer-
encesthatareopentothepublic.Personswishingtoattendanymeetingand/ortelephoneconferenceshouldcontactthe
Secretaryofthe B31StandardsCommittee.
TheASMEB31CodeforPressurePipingconsistsofanumberofindividuallypublishedSections,eachanAmerican
NationalStandard.RulesforeachSectionreflectthekindsofpipinginstallationsconsideredduringitsdevelopment,as
follows:
B31.1 PowerPiping :pipingtypicallyfoundinelectricpow er-g eneratingstations,industrialandinstitutionalplants,
g eothermal heatingsystems,andcentralanddistrictheatingandcoolingsystems
B31.3 ProcessPiping :pipingtypicallyfoundinpetroleumrefineries;onshoreandoffshorepetroleumandnaturalg as
productionfacilities;chemical,pharmaceutical,tex tile,paper,oreprocessing ,semiconductor,andcryog enic
plants;foodandbeverag eprocessingfacilities;andrelatedprocessingplants andterminals
B31.4 PipelineTransportationSystemsforLiquids andSlurries:pipingtransportinghazardous productsthatare
predominatelyliquidbetweenfacilities,productionandstorag efields, plants, andterminals,andwithin
terminals andpumping , reg ulating , andmeteringstations associatedwithliquidpipeline systems
B31.5 Refrig erationPipingandHeatTransferComponents: pipingforrefrig erants andsecondarycoolants
B31.8 GasTransmissionandDistributionPipingSystems:pipingtransportingproductsthatarepredominatelyg as
betweensourcesandterminals,includingcompressor,reg ulating ,andmeteringstations,andg asg athering
pipelines
B31.9 BuildingServicesPiping :pipingtypicallyfoundinindustrial,institutional,commercial,andpublicbuilding s,and
inmulti-unitresidences,thatdoesnotrequiretherang eofsizes,pressures,andtemperatures coveredin
B31.1
B31.12 Hydrog enPipingandPipelines: pipinging aseous andliquidhydrog enservice andpipelines ing aseous
hydrog enservice
ThisisCodeSectionB31.4,PipelineTransportationSystemsforLiquidsandSlurries.Hereafter,inthisIntroductionand
inthetex tofthisCodeSectionB31.4,wherethew ord“ Code”isusedwithoutspecificidentification,itmeansthisCode
Section.
Itis the user’s responsibilitytoselecttheCode Sectionthatmostnearlyapplies toaproposedpipinginstallation.
FactorstobeconsideredincludelimitationsoftheCodeSection,jurisdictionalrequirements,andtheapplicabilityofother
codesandstandards.AllapplicablerequirementsoftheselectedCodeSectionshallbemet.Forsomeinstallations,more
thanoneCodeSectionmayapplytodifferentpartsoftheinstallation.Certainpipingwithinafacilitymaybesubjectto
othernationalorindustrycodesandstandards.Theuserisalsoresponsibleforimposingrequirementssupplementaryto
thoseofthe Codeifnecessaryto ensure safe pipingforthe proposedinstallation.
TheCodespecifies eng ineeringrequirementsdeemednecessaryforsafedesig n,construction,operation,andmain-
tenanceofpressurepiping .Whilesafetyistheprimaryconsideration,thisfactoralonewillnotnecessarilyg overnthefinal
specificationsforanypipinginstallationoroperation.TheCodeisnotadesig nhandbook.Manydecisionsthatmustbe
madetoproduceasoundpipinginstallationandtomaintainsysteminteg rityduringoperationarenotspecifiedindetail
w ithinthisCode.TheCodedoesnotserveasasubstituteforsoundeng ineeringjudg mentsbytheoperatingcompanyand
the desig ner.
To thegreatestpossible ex tent, Code requirementsfordesignare statedinterms ofbasicdesignprinciples and
for mulas.Thesearesupplementedasnecessaryw ithspecificrequirementstoensureuniformapplicationofprinciples
andtog uideselectionandapplicationofpipingelements.TheCodeprohibitsdesig nsandpracticesknowntobeunsafe
andcontains w arning sw here caution, butnotprohibition, is warranted.
This CodeSectionincludes
(a) referencestoacceptablematerialspecificationsandcomponentstandards,includingdimensionalrequirements
andpressure–temperature rating s
(b) requirementsfordesig nofcomponents andassemblies, includingpipe supports
(c) requirementsanddataforevaluationandlimitationofstresses,reactions,andmovementsassociatedwithpres-
sure, temperaturechang es, andotherforces
(d) g uidance andlimitations ontheselectionandapplicationofmaterials,components, andjoiningmethods
(g) procedures foroperationandmaintenance thatare essential topublicsafety
(h) provisions forprotectingpipelines fromex ternalcorrosionandinternalcorrosion/erosion
ItisintendedthatthiseditionofCodeSectionB31.4notberetroactive.Unlessag reementisspecificallymadebetw een
contractingpartiestouseanotheredition,orthereg ulatorybodyhavingjurisdictionimposestheuseofanotheredition,
thelatesteditionissuedatleast6monthspriortotheorig inalcontractdateforthefirstphaseofactivitycoveringapiping
systemorsystems shall be the g overningdocumentforall desig n, materials,fabrication,erection, ex amination, and
testingforthe pipinguntil thecompletionofthe workandinitial operation.
UsersofthisCodearecautionedag ainstmakinguseofCoderevisionsw ithoutassurancethattheyareacceptabletothe
properauthorities inthe jurisdictionwhere the pipingis to be installed.
Codeusers willnotethatparag raphs intheCode arenotnecessarilynumberedconsecutively.Suchdiscontinuities
resultfromfollow ingacommonoutline,insofaraspracticable,forallCodeSections.Inthisw ay,correspondingmaterialis
corresponding lynumberedinmostCodeSections,thusfacilitatingreferencebythosewhohaveoccasiontousemorethan
one Section.
TheCodeisunderthedirectionofA SMECommitteeB31,CodeforPressurePiping ,w hichisorg anizedandoperates
underproceduresofTheA mericanSocietyofMechanicalEng ineersthathavebeenaccreditedbytheA mericanNational
StandardsInstitute.TheCommitteeisacontinuingoneandkeepsallCodeSectionscurrentwithnewdevelopmentsin
materials, construction,andindustrial practice.Neweditions arepublishedatintervals of3to 5 years.
WhennoSectionoftheA SMECodeforPressurePipingspecificallycoversapipingsystem,athisdiscretiontheusermay
selectanySectiondeterminedtobeg enerallyapplicable.However,itiscautionedthatsupplementaryrequirementsto
theSectionchosenmaybenecessarytoprovideforasafepipingsystemfortheintendedapplication.Technicallimitations
ofthevariousSections,leg alrequirements,andpossibleapplicabilityofothercodesorstandardsaresomeofthefactors
tobe consideredbythe userindeterminingthe applicabilityofanySectionofthis Code.
TheCommitteehas establishedanorderlyprocedure toconsiderrequests forinterpretationandrevisionofCode
requirements. To receive consideration, inquiries must be in writing and must give full particulars (see
Correspondence With theB31 Committee coveringpreparationoftechnical inquiries).
The approvedreplyto aninquirywillbe sentdirectlytothe inquirer.Inaddition,the questionandreplywill be
publishedonthe A SMEInterpretations Database.
ACaseistheprescribedformofreplytoaninquirywhenstudyindicatesthattheCodewordingneedsclarificationor
w henthe replymodifies ex istingrequirementsoftheCodeorg rantspermissiontousenewmaterialsoralternative
constructions. The Case will be publishedontheB31.4 web pag eathttp://cstools.asme.org /.
ACaseisnormallyissuedforalimitedperiod,afterw hichitmayberenewed,incorporatedintheCode,orallowedto
ex pireifthereisnoindicationoffurtherneedfortherequirementscoveredbytheCase.However,theprovisionsofaCase
maybeusedafterits ex pirationorw ithdrawal,providedtheCasewas effectiveonthe orig inalcontractdate orw as
adoptedbefore completionofthe w ork, andthecontractingparties ag ree toits use.
Materialsare listedinthestress tables onlywhensufficientusag einpipingwithinthescopeofthe Code hasbeen
shown.MaterialsmaybecoveredbyaCase.Requestsforlistingshallincludeevidenceofsatisfactoryusag eandspecific
datatopermitestablishmentofallowablestresses,max imumandminimumtemperaturelimits,andotherrestrictions.
Additionalcriteriacanbefoundintheg uidelinesforadditionofnewmaterialsintheA SMEBoilerandPressureV essel
Code,SectionIIandSectionV III,Division1,A ppendixB.(Todevelopusag eandg ainex perience,unlistedmaterialsmaybe
usedinaccordancew ith para. 423.1.)
SUMMA RY OF CHA NGES
FollowingapprovalbytheA SMEB31CommitteeandA SME,andafterpublicreview,A SMEB31.4-2019wasapprovedby
the A mericanNational Standards InstituteonJuly18, 2019.
A SMEB31.4-2019 includesthe followingchang es identifiedbyamarg innote, (19).
Page Location Change
x i CorrespondenceWith the B31
Committee
A dded
2 400.1.1 (1) Subparag raph (b) added, andremainingsubparag raphs
redesig nated
(2) Subparag raphs (d) and(e) [formerly(c) and(d)] revised
13 402.1 Secondparag raphrevised
17 402.5.2 (1) Notedesig nationdeleted
(2) Nomenclature revised
17 402.6.1 DefinitionofArevised
17 402.6.2 DefinitionofAandfinal parag raph revised
18 403.2.1 (1) Equationandnomenclaturerevised
(2) Final parag raph deleted
23 403.9.1 Note added
24 404.1.2 Revised
25 404.2.3 Final parag raph revised
33 Fig ure 404.3.5-1 (1) DefinitionofL removedfromfig ureandaddedtothe
nomenclature
(2) Nomenclature revised
33 404.4.1 Firstparag raph revised
34 404.5.1 Final parag raph revised
36 404.11 Firstparag raph revised
38 425 Revisedinitsentirety
39 Table 423.1-1 Title revised
41 426.3 Revised
43 434.2.2 Revised
43 434.4 Revised
44 434.7.1 Subparag raph(a) revised
45 434.8.2 Subparag raph(a) revised
47 434.8.9 Subparag raph(a) revised
51 434.13.5 Subparag raph(b) revised
52 434.15.2 Subparag raph(f) added
53 434.18 Subparag raph(b)(1) revised
56 435.4.3 Revised
59 437.4.1 Subparag raph(a) revised
59 437.6.4 Revised
62 451.6.1 Subparag raph(g ) revised
65 451.6.2.6 Firstparag raph revised
66 451.6.2.9 Firstparag raph andsubparas. (b) and(d) revised
68 451.9 Subparag raph(a) revised
69 Table 451.6.2.9-1 Entryinsix throwoffourthcolumnrevised
71 452.7 Subparag raph(d) revised
74 461.1.2 Subparag raphs (a) and(b) revised
75 461.1.7 Final sentencerevised
77 462.1 Final sentencerevised
77 462.2 Subparag raph(g )(1) revised
78 462.3 Subparag raphs (b)(1), (b)(2), (b)(3),(b)(5), (b)(6), and(b)(7)
revised
78 463.1 Subparag raph(b) revised
80 466.1.1 Secondandthirdparag raphs revised
81 467 Final sentencerevised
82 A400 Subparag raph(d) revised
83 A401 Revisedinits entirety
85 A402 Revisedinits entirety
89 A403 Revisedinits entirety
90 A404.4.3 (1) Redesig natedfromorig inal A 404.4.1
(2) Titlerevised
90 A404.8.3 Revised
90 A405 A 405.1(a) andA 405.2 revised
90 A406.3 FormerA 421 revisedandredesig natedas A 406.3
91 A423.2 Final sentencerevised
91 A434.2.2 FormerA 434.2 redesig natedas A 434.2.2
91 A434.8 TitlesofA 434.8.3,A434.8.5,A 434.8.5(a),andA 434.8.5(b)revised
92 A434.13.1 Revised
92 A434.25 (1) FormerA 434.14 redesig natedas A 434.25
(2) Cross-references updated
92 A436.5.1 (1)Subparag raphs(9),(11),(12),(13),and(15)redesig natedas
(19) throug h(23)
(2) Subparag raph (23) [formerly(15)] revised
93 A451.3 Title revised
93 A451.5 Final sentencedeleted
94 A451.6 Final parag raph added
94 A451.6.2 Revisedinits entirety
94 A451.10 Title revised
95 A460 Subparag raph(c) revised
95 A461 (1) Titles ofA 461, A461.1.2, A 461.1.3, andA 461.1.5revised
(2) A 461.1.1(c) redesig natedas A 461.1.1(a)
(3) InA 461.3,subparag raphs redesig nated,andreference
updated
99 C400.2 Definitionofductileiron revised
100 C404.4.1 Revised
103 MandatoryA ppendixI Updated
107 NonmandatoryA ppendixA InformationmovedtoCorrespondenceWiththeB31Committee
pag e
109 Index Updated
Cha pter I
Sc ope a nd Definitions
400 GENER A LST A T EMENT S
(a) ThispipelinetransportationsystemsCodeisoneof
severalsections ofThe A mericanSocietyofMechanical
Engineers Code forPressure Piping, ASME B31, andit
is t he responsibilit y oft he useroft his Code t o select
theapplicableSection.ThisSectionispublishedasasepa-
ratedocumentforconvenience.ThisCodeis intendedto
applytopipelinesystemstransportingliquids including ,
butnotlimitedto,crudeoil,condensate,liquidpetroleum
products, natural g asoline, naturalgas liquids, liquefied
petroleum gas, carbon dioxide (supercritical), liquid
alcohol, liquid anhydrous ammonia, produced water,
injectionw ater,brine,biofuels,andslurries.Throug hout
thisCode,thesesystemsw illbereferredtoasliquidpipe-
line systems.
(b) The requirement s oft his Code are adequat e for
safety under conditions normallyencounteredinthe
operat ionofliquidpipeline sy stems. R equirements for
all abnormal orunusual condit ions are notspecifically
provided for, nor are all details of engineering and
constructionprescribed. A llworkperformedw ithinthe
scopeofthisCodeshallcomplywiththesafetystandards
ex pressedorimplied.
(c ) The primary purpose ofthis Code is to est ablish
requirement s forsafe design, const ruct ion, inspect ion,
test ing, operat ion, andmaint enance ofliquidpipeline
systemsforprotectionoftheg eneralpublicandoperating
companypersonnel,aswellasforreasonableprotectionof
the pipingsystem against vandalism andaccidental
damag ebyothers,andreasonable protectionofthe en-
vironment.
(d) ThisCodeisconcernedwithemployeesafetytothe
ex tentthatitisaffectedbybasicdesig n,qualityofmate-
rials andworkmanship, andrequirements forconstruc-
tion, inspection, testing,operation, andmaintenance of
liquidpipelinesystems.Ex istingindustrialsafetyreg ula-
tionspertainingtoworkareas, safe workpractices, and
safetydevicesarenotintendedtobesupplantedbythis
Code.
(e) The designeris caut ionedt hatt he Code is nota
designhandbook. The Code does notdoaw ayw ith the
needfortheeng ineerorcompetenteng ineeringjudg ment.
The Code generallyemploy s asimplifiedapproach for
manyofits requirements.
(1) For designand construction, a designermay
choose to use amore complet eandrigorous analysis
to develop design and construction requirements.
Whent he designer decides to t ake t his approach, t he
designershall prov ide details andcalculations demon-
st rat ingdesign, const ruct ion, examinat ion, andt est ing
are consistent with the criteria of this Code. These
details shall be adequate forthe operatingcompanyto
verifythevalidityoftheapproachandshallbeapproved
by t he operatingcompany. The det ails shall be docu-
mentedinthe eng ineeringdesig n.
(2) Foroperationandmaintenance, the operating
company may choose t o use a more rigorous analysis
to develop operation andmaintenance requirements.
When the operating company decides to take this
approach, t he operatingcompany shall prov ide details
andcalculationsdemonstratingthatsuchalternativeprac-
tices areconsistentw iththeobjectivesofthis Code.The
detailsshallbedocumentedintheoperatingrecordsand
retainedforthe lifetime ofthe facility.
(f) This Code shallnotbe retroactiveorconstruedas
apply ingt o piping sy st ems installedbefore thedate of
issuance shown on t he documentt it le page insofaras
design, materials, construction, assembly, inspection,
andtestingare concerned. Itis intended,how ever,that
the prov isions ofthis Code shall beapplicable w ithin6
months afterdateofissuance totherelocation, replace-
ment , anduprating orotherwise changing ofexisting
pipingsystems;andto theoperation, maintenance, and
corrosioncontrol ofnew or existingpipingsystems.
Aft erCode rev isions are approv edby ASMEandANSI,
theymay be usedby agreementbet weencontracting
part ies beginning wit h t he dat eofissuance. Revisions
become mandatoryorminimumrequirement sfornew
installations 6 months afterdateofissuanceexceptfor
piping installations orcomponents contracted for or
underconstructionpriortotheendofthe6-monthperiod.
(g) The users ofthis Code are adv isedt hatin some
areasleg islationmayestablishg overnmentaljurisdiction
overt he subjectmat t ercoveredby t his Code andare
cautionedagainstmakinguse ofrevisions thatareless
restrictive thanformer requirements without having
assurance thatt heyhav e beenaccept edbythe proper
authorities inthejurisdictionw herethe pipingis tobe
installed. The DepartmentofTransportation, United
Stat es ofAmerica, rules governingt he t ransport ation
bypipelineininterstateandforeig ncommerceofpetro-
leum,petroleumproducts,andliquidssuchasanhydrous
ammoniaorcarbondiox ideareprescribedunderPart195
—TransportationofHazardousLiquidsbyPipeline,Title
49 —Transportation, Code ofFederal Reg ulations.
400.1 Scope
400.1.1
ð19Þ This Code prescribes requirement s for t he
design, mat erials, construction, assembly, inspection,
t est ing, operat ion, andmaint enance ofliquidpipeline
systems between production fields or facilities, tank
farms,above- orbelow g roundstorag efacilities, natural
gas processing plants, ref ineries, pump stations,
ammoniaplants, terminals (marine, rail, and truck),
andotherdeliveryandreceivingpoints,aswellaspipe-
lines transporting liquids within pump stations, tank
farms, andterminals associated with liquid pipeline
systems (see Fig ures 400.1.1-1 and400.1.1-2).
ThisCodealsoprescribesrequirementsforthedesig n,
materials, construction, assembly, inspection, test ing,
operation, and maintenance ofpiping transporting
aqueous slurries ofnonhazardous materials such as
coal,mineralores,concentrates,andothersolidmaterials,
between a slurry processingplantorterminal and a
receivingplantorterminal(see Fig ure400.1.1-3).
Pipingconsistsofpipe,flang es,bolting ,g askets,valves,
reliefdevices,fitting s,andthepressure-containingparts
ofotherpipingcomponents.Italsoincludeshang ersand
supports,andotherequipmentitemsnecessarytoprevent
overstressingthe pressure-containingparts.Itdoes not
include supportstructures such as frames ofbuildings,
st anchions, orfoundations, or any equipmentsuch as
definedinpara. 400.1.2(b).
Requirements for offshore pipelines are found in
ChapterIX. R equirements forcarbondioxide pipelines
arefoundinChapterX.Requirementsforslurrypipelines
are foundinChapterX I.
A lsoincludedwithinthescopeofthis Code are
(a) primaryandassociatedaux iliaryliquidpetroleum
andliquidanhydrous ammoniapipingatpipelineterm-
inals(marine,rail,andtruck),tankfarms,pumpstations,
pressure-reducing stations, and metering stations,
includingscrapertraps, strainers, andproverloops
(b) primaryandaux iliaryslurrypipingatstorag efacil-
ities, pipeline terminals, pump stations, chok estations,
andpressure-reducingst at ions, includingpipingup t o
the firstvalveofattachedaux iliarywaterlines
(c) storage and workingtanks, includingpipe-type
storag efabricatedfrompipeandfitting s,andpipinginter-
connectingthese facilities
(d) liquidpetroleum, liquidanhydrous ammonia, and
slurrypipinglocatedonpropertythathasbeendesig nated
forsuchpipingwithinpetroleumrefinery,naturalg aso-
line, gas processing, ammonia, bulkplant s, and slurry
transportationsystems
(e) those aspects ofoperation and maintenance of
liquid and slurry pipeline systems relating to the
safet yandprot ect ion oft he general public, operat ing
company personnel, environment, property, and the
pipingsystems[see paras. 400(c) and400(d)]
400.1.2 This Code w as notdevelopedto apply to
(a) buildingservicepiping ,suchaswater,air,orsteam
(b) pressurevessels,heatex chang ers,pumps,meters,
andothersuchequipment,includinginternalpipingand
connections for piping except as limited by
para. 423.2.4(b)
(c) piping with adesign temperature below−20°F
(−30°C) or above 250°F (120°C) [for applications
below−20°F(−30°C),seeparas.423.2.1(a) and423.2.6]
(d) casing ,tubing ,orpipeusedinoilwellsandwellhead
assemblies
400.2 Definitions
Someofthemorecommontermsrelatingtopipingare
definedbelow.ForweldingtermsusedinthisCodebutnot
shownhere, definit ions in accordance wit hAWS A3.0
apply.
accidentalloads:anyunplannedloadorcombinationof
unplanned loads caused by human intervention or
natural phenomena.
act ive cor r osion: corrosion that is continuingornot
arrested.
anomaly:anindication,detectedbynondestructiveex am-
ination(such as in-line inspection).
arc w el d ing (AW) 1
: a group ofweldingprocesses t hat
produces coalescence ofworkpieces by heatingthem
with an arc. The processes are used with orwithout
the applicat ionofpressure andwit hor withoutfiller
metal.
automatic welding 1
: welding with equipment that
requires only occasional or no observation ofthe
welding, andno manual adjust mentoft he equipment
controls.
backfill:materialplacedinaholeortrenchtofillex cavated
spacearoundapipeline.
bluntimperfection: an imperfection characterizedby
smoothlycontouredvariations inw all thickness.
2
breakawaycoupling:acomponentinstalledinthepipeline
toallowthepipeline toseparatewhenapredetermined
ax ial loadis appliedtothe coupling .
buckl e:a condit ionwhere t he pipeline has undergone
sufficientplasticdeformationtocausepermanentw rink-
ling in the pipe wall or excessive cross-sectional
1
Theseweldingtermsag reew ithA WSA3.0.
2
Sharpimperfect ionsmayberenderedbluntbygrinding,butt he
absenceofasharpimperfectionmustbeverifiedbyv isualandnonde-
structiveexamination.
Figure 400.1.1-1 Dia gra m Show ing Sc opeofA SMEB31.4Exc l uding Ca rbon DioxidePipel ineSy stems
(SeeFigur e400.1.1-2)
Figur e400.1.1-2Dia gra mShow ingSc opeofASMEB31.4forCa rbonDioxidePipel ineSy stems
NOTES:
(1) Onshoreoroffshore.
(2) Marine,rail,ortruck(allloadingorunloading ).
Figure400.1.1-3Dia gra mShow ing Sc opeofASMEB31.4forSl urryPipel ineSy stems
Processing plant/terminal
Pipeline terminal*
Tank farm and/or pump station
Receiving plant/terminal
Piping w ithin B31.4 scope
Continuationof B31.4 scope through area
Start or endat B31.4 scope w ithinplot area
Plot limits of processing plant or receivingplant
Property line of processing plant or receivingplant Marine, rail, or truck (allloadingor unloading)
*
deformationcausedbyloadsactingaloneorincombina-
tionwithhydrostaticpressure.
buttweld(typically, abuttjoint, singleV-grooveweld):a
weldbetw eentw omembersalig nedapprox imatelyinthe
same plane.
cathodicprotection(CP):technique toreducethe corro-
sionofametalsurfacebymakingthatsurfacethecathode
ofanelectrochemical cell.
characterize:toquantifythetype,size,shape,orientation,
andlocationofananomaly.
c oati ng: liquid, liquefiable, ormast ic compositiont hat,
aft erapplicat ion toa surface, is conv ert edint o asolid
protective or functional adherent film. Coating also
includestape wrap.
coating system: complete number andtypes ofcoats
applied t o asurface in apredet ermined order. (W hen
usedinabroadersense, surface preparation, pretreat-
ments, dry film thickness, and manner ofapplication
are included.)
coldspringing:deliberatedeflectionofpiping ,withinits
yield st rengt h, to compensat eforanticipat ed thermal
ex pansion.
column buckling: buckling of a beam or pipe under
compressive axial loadinwhich loads cause unst able
lateraldeflection;also referredto asupheavalbuckling .
c omponent: anindiv idual itemorelementfittedinline
w ith pipe inapipeline sy stem, such as, butnotlimited
to,valves, elbows,tees, flang es, andclosures.
connector s: components, exceptflanges, usedforthe
purpose ofmechanicallyjoiningtwosections ofpipe.
consequence:impactthatapipelinefailurecouldhaveon
the public, employees,property, andtheenvironment.
corrosion:deteriorationofamaterial,usuallyametal,that
results fromareactionw ith its environment.
corrosioninhibitor:chemicalsubstanceorcombinationof
substancesthat,whenpresentintheenvironmentorona
surface, prevents orreduces corrosion.
defect 1
:adiscontinuityordiscontinuitiesthatbynatureor
accumulat edeffectrenderapartor productunable t o
meetminimumapplicableacceptancestandardsorspeci-
fications.The termdesig natesrejectability.
dent:permanentconcavedeformationofthecircularcross
section ofthe pipe thatproduces a decrease in the
diameter.
desi gn life: aperiodoftime usedindesig ncalculations,
selectedforthe purpose ofv erifyingthatareplaceable
orpermanentcomponentis suitableforthe anticipated
periodofservice. Designlife does notpertain to the
lifeofthepipelinesystembecauseaproperlymaintained
andprotectedpipeline systemcanprovide liquidtrans-
portationserviceindefinitely.
detect:tosenseorobtainmeasurableindicationsfroman
anomalyorcoatingflawinapipelineusingin-lineinspec-
tionorothertechnolog ies.
discontinuity 1
:aninterruptionofthetypicalstructureofa
material,suchasalackofhomog eneityinitsmechanical,
metallurg ical,orphysicalcharacteristics.Adiscontinuity
is notnecessarilyadefect.
d uc til i ty :measure oft he capabilit y ofa mat erial t o be
deformedplasticallybefore fracturing .
electroly te: achemical substance cont ainingions that
mig rateinanelectricfield.ForpurposesofthisCode,elec-
trolytesincludethesoilorliquidadjacenttoandincontact
withaburiedorsubmerg edmetallicpipingsystem,aswell
as some transportedliquidproducts.
employer:theow ner,manufacturer,fabricator,contractor,
assembler, orinstaller responsible for the welding,
brazing, and NDE perf ormed by his organization,
includingprocedure andperformance qualifications.
engineeringde sign:detaileddesig ndevelopedfromoper-
atingrequirementsandconformingtoCoderequirements,
including all necessary drawings and specifications,
g overningapipinginstallation.
environment:surrounding sorconditions(physical,chem-
ical, ormechanical) inwhichamaterial ex ists.
epoxy:typeofresinformedbythereactionofaliphaticor
aromat ic poly ols (likebisphenol) w it hepichlorohy drin
andcharact erized byt he presence ofreact iv e oxirane
endg roups.
evaluation:ar eview,followingthecharacterizationofan
actionable anomaly,todeterminew hetherthe anomaly
meets specifiedacceptancecriteria.
examination:directphysicalinspectionofapipelinew hich
mayincludetheuseofnondestructiveex amination(NDE)
techniques ormethods.
experience:workactivitiesaccomplishedinaspecificNDT
methodunderthe directionofqualifiedsupervision,
including the performance ofthe NDT method and
relatedactiv ities, butnotincludingtime spentinorga-
nizedtrainingprog rams.
failure:g eneraltermusedtoimplythatapartinservice
hasbecomecompletelyinoperable;isstilloperablebutis
incapable ofsatisfactorilyperformingits intendedfunc-
tion;orhasdeterioratedseriouslytothepointthatithas
become unreliableorunsafe forcontinueduse.
fati gue: process ofdev elopmentoforenlargementofa
crackas aresultofrepeatedcycles ofstress.
filletweld 1
: a weldofapproximately triangularcross
section joining two surfaces approximately at right
ang lestoeachotherinalapjoint,teejoint,orcornerjoint.
film: thin, notnecessarilyvisible layerofmaterial.
fullfilletweld 1
:afilletweldw hosesizeisequaltothethick-
ness ofthe thinnermemberjoined.
gasmetalarcwelding(GMAW) 1
:anarcweldingprocess
thatuses anarc betweenacontinuous fillermetal elec-
trodeandtheweldpool.Theprocessisusedwithshielding
fromanex ternallysuppliedg asandwithouttheapplica-
tionofpressure.
gastungstenarcwelding(GTAW) 1
:anarcw eldingprocess
thatusesanarcbetweenatung stenelectrode (noncon-
sumable) andt he weld pool. The process is usedw it h
shieldingg as andw ithoutthe applicationofpressure.
generalc orros i on:uniformorgraduallyv ary ingloss of
wall thickness overanarea.
girthweld:acompletecircumferentialbuttweldjoining
pipe orcomponents.
gouge:mechanicallyinducedmetalloss,whichcauseslo-
calizedelong atedg roovesorcavitiesinametalpipeline.
hydrostatictestorhydrotest:apressuretestusingwateras
the testmedium.
imperfection:discontinuityorirreg ularitythatisdetected
byinspection.
incident:unintentionalreleaseofliquidduetothefailure
ofapipeline.
inclusion:nonmetallicphasesuchasanox ide,sulfide,or
silicateparticle inametalpipeline.
i nd i cati on: finding froma nondest ruct iv e t est ingt ech-
nique ormethod that deviates from the expected. It
mayormaynotbe adefect.
in-lineinspection(ILI):steelpipelineinspectiontechnique
thatusesdevicesknownintheindustryasintellig entor
smartpig s.Thesedevicesruninsidethepipeandprovide
indicationsofmetalloss,deformation,andotherdefects.
in-lineinspectiontools:anyinstrumenteddeviceorvehicle
thatrecordsdataandusesnondestructivetestmethodsor
othertechniquestoinspectthe pipeline fromtheinside.
A lso knownas intellig entorsmartpig .
i n-s ervi c e pi peli ne: apipeline thatcontains liquidto be
transported.The liquidmayormaynotbe flowing .
inspec ti on:use ofanondestructivetestingtechniqueor
method.
i ntegri ty: the capabilityofthe pipelinet o w ithstandall
anticipatedloads(includinghoopstressduetooperating
pressure) wit hin t he designfact or est ablished byt his
section.
integrityassessment:process thatincludes inspectionof
pipeline facilit ies, evaluat ing t he indicat ions result ing
f rom the inspections, examining the pipe using a
varietyoftechniques,evaluatingtheresultsoftheex am-
inations,characterizingtheevaluationbydefecttypeand
sev erit y ,anddeterminingthe resultingintegrityofthe
pipeline throug hanalysis.
internaldesignpressure:internalpressureusedincalcula-
tionsoranalysisforpressuredesig nofapipingcompo-
nent(seepara.401.2.2.2);itincludesfactorspresentedin
para. 403.2.1.
launcher:pipelinedeviceusedtoinsertapigintoapres-
surizedpipeline, sometimes referredtoas apigtrap.
leak:unintentionalescapeofliquidfromthepipeline.The
sourceoftheleakmaybeholes,cracks(includingpropa-
g atingandnonpropag ating , long itudinal, andcircumfer-
ential), separation, orpull-outandloose connections.
length:apieceofpipeoftheleng thdeliveredfromthemill.
Eachpieceiscalledaleng th,reg ardlessofitsactualdimen-
sion. This is sometimes calleda joint, but “length” is
preferred.
l i ne s ecti on orpipel i ne s ecti on: cont inuous runofpipe
between adjacent pump stations, between a pump
stationand ablockvalve, or between adjacentblock
valves.
liquefied pet roleum gas(es) (LPG): liquid petroleum
composedpredominantlyofthefollowinghydrocarbons,
eitherby themselves or as mixtures: butane (normal
butane orisobutane), butylene (including isomers),
propane,propylene, andethane.
liquidalcohol: any ofa group oforganic compounds
containing only hydrogen, carbon, and one or more
hydroxyl radicals that will remainliquidin amoving
streaminapipeline.
l i qui danhydrousammoni a:acompoundformedbythe
combinationofthe tw o gaseous elements nitrogenand
hy drogen, in t he proport ionofone partofnit rogent o
three parts ofhydrogen, by volume, compressed to a
liquidstate.
magnetic-particleinspection(MPI):anondestructivetest
methodutilizingmag neticleakag efieldsandsuitableindi-
cating materials to disclose surface andnear-surface
discontinuityindications.
mainlinepipelines:allin-linepipelinepipes,fitting s,bends,
elbows,checkvalves, andblockvalves betweenscraper
traps.
maxi mumoperatingpress ure:apressure establishedby
t he operat ingcompany t hatis t he highestpressure at
whichapipingsystemcanbeoperatedwithappropriate
considerationfor
(a) internaldesig npressure
(b) hydrostatictestpressure
(c) desig npressure ofanypipelinecomponents
(d) safe operatingpressure
(e) deviations fromnormal steady-state operating
conditions
maximumsteady-stateoperatingpressure:max imumpres-
sure (sumofstaticheadpressure, pressure requiredto
overcome friction losses, and any back pressure) at
anypointinapipingsystemwhenthesystemisoperating
understeady-state conditions.
mechanicaldamage:typeofmetaldamag einapipeorpipe
coat ingcausedbyt he applicat ionofanext ernal force.
Mechanical damage can include denting, coating
removal, metal removal, metal movement, cold
workingoftheunderlyingmetal,puncturing ,andresidual
stresses.
metalloss:typesofanomaliesinpipeinwhichmetalhas
beenremovedfromthepipesurface,usuallyduetocorro-
sionorg oug ing .
miter:tw oormorestraig htsectionsofpipematchedand
joinedonalinebisectingthe angleofjunctionsoas to
produce achang eindirection.
mitigati on: limitationorreductionofthe probabilityof
occurrence orexpected consequence for aparticular
event.
nominalpipesize(NPS):seeA SMEB36.10M,p.1fordefi-
nition.
nondest r uct ive examinat ion (NDE ) or nondest r uctive
testing(NDT):testingmethod,suchasradiog raphy,ultra-
sonic, magnetictesting, liquidpenetrant, visual, leak
testing, eddy current, and acoustic emission, or a
testing technique, such as magnetic f lux leakage,
magnetic-particle inspection, shear-wave ultrasonic,
andcontactcompression-w aveultrasonic.
operatororoperating c ompany:indiv idual, partnership,
corporation, public agency, owner, agent, or other
entitycurrentlyresponsibleforthedesig n,construction,
inspect ion, t est ing, operat ion, andmaint enance oft he
pipeline facilities.
oxyfuelgaswelding(OFW) 1
:ag roupofweldingprocesses
thatproducescoalescenceofworkpiecesbyheatingthem
withanox yfuelg asflame.Theprocessesareusedw ithor
withouttheapplicationofpressureandw ithorwithout
fillermetal.
petroleum:crudeoil,condensate,naturalg asoline,natural
g asliquids,liquefiedpetroleumg as,andliquidpetroleum
products.
pig:adevicepassedinternallythroug htheinsideofapipe-
linetocleanorinspectthepipeline,ortoseparatebatch
fluids.
pi ggi ng:use ofany independent, self-containeddev ice,
tool,orvehiclethatmovesthroug htheinteriorofthepipe-
line forinspecting , dimensioning , cleaning , ordrying .
pipe:atube,usuallycylindrical,usedforconveyingafluid
ortransmittingfluidpressure,normallydesig nated“pipe”
intheapplicablespecification.Italsoincludesanysimilar
componentdesignated as “tubing” usedfor the same
purpose.Typesofpipe,accordingtothemethodofmanu-
facture,are definedbelow.
double submergedarcweldedpipe: pipe havingalon-
g itudinalorhelicalseambuttjointproducedbyatleast
t wopasses, one ofwhich is ont he inside ofthe pipe.
Coalescence is produced by heating with an electric
arcorarcsbetw eenthebaremetalelectrodeorelectrodes
andthework.Thew eldingisshieldedbyablanketofg ran-
ular,fusiblematerialonthework.Pressureisnotusedand
fillermetalforthe inside andoutside welds isobtained
fromtheelectrode orelectrodes.
electricflashweldedpipe:pipehavingalong itudinalbutt
joint whereincoalescence is producedsimult aneously
over the entire area ofabutting surfaces by the heat
obtainedfromresistance tothe flowofelectric current
betweenthetw osurfaces,andbytheapplicationofpres-
sureafterheatingissubstantiallycompleted.Flashingand
upsettingareaccompaniedbyex pulsionofmetalfromthe
joint.
electricfusionweldedpipe:pipehavingalong itudinalor
helicalseambuttjointw hereincoalescenceisproducedin
thepreformedtubebymanualorautomaticelectricarc
welding . The weldmaybe sing le ordouble andmaybe
madewithorwithouttheuseoffillermetal.Helicalseam
w eldedpipe is alsomadeby theelectricfusionw elded
process with eitheralap jointoralock-seamjoint.
electricinductionweldedpipe:pipeproducedinindivi-
dual lengths orincontinuous lengths fromcoiledskelp
having a longitudinal or helical seam butt joint
w hereincoalescence is producedby the heatobt ained
fromresistanceofthe pipe toinducedelectriccurrent,
andbyapplicationofpressure.
electricresistanceweldedpipe:pipe producedinindi-
vidualleng thsorincontinuousleng thsfromcoiledskelp,
havingalong itudinal orhelical seambuttjointwherein
coalescenceisproducedbytheheatobtainedfromresis-
tanceofthepipetotheflowofelectriccurrentinacircuitof
whichthepipeisapart,andbytheapplicationofpressure.
furnacebuttweldedpipe:
furnacebuttweldedpipe,bellwelded:pipeproduced
inindividualleng thsfromcut-leng thskelp,havingitslon-
g itudinalbuttjointforg ew eldedbythemechanicalpres-
sure developedindrawing the furnace-heated skelp
through a cone-shapeddie (commonly knownas the
“ w el
