英文版dl 5031-1994　电力建设施工及验收技术规范 管道篇.doc

ELECTRICPOWERTRADESTANDARDOFTHEPEOPLESREPUBLICOFCHINATHECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONPIPINGSECTIONDL503194CHIEFEDITORIALDEPARTMENTCONSTRUCTIONCOOPERATINGDEPARTMENTOFTHEMINISTRYOFPOWERINDUSTRYAPPROVEDDEPARTMENTTHEMINISTRYOFPOWERINDUSTRYOFPRC1994BEIJINGNOTETHISBOOKISTHEENGLISHTRANSLATIONOFTHECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONPIPINGSECTIONDL503194INTHEEVENTOFANYINCONSISTENCYBETWEENTHECHINESELANGUAGETEXTOFTHECODEANDTHEPRESENTENGLISHLANGUAGETEXTOFTHECODE,THECHINESELANGUAGETEXTSHALLBETAKENASRULINGTHEMINISTRYOFPOWERINDUSTRYOFTHEPEOPLESREPUBLICOFCHINATHENOTIFICATIONOFISSUINGTHEELECTRICPOWERTRADESTANDARDTHECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONPIPINGSECTIONELECTRICPOWERTECHNOLOGY1994NO208ALLELECTRICPOWERADMINISTRATIONS,ALLELECTRICPOWERBUREAU,ELECTRICPOWERPLANNINGINSTITUTES,ANDELECTRICPOWERCONSTRUCTIONINSTITUTESOFPROVINCESMUNICIPALITIESDIRECTLYUNDERTHECENTRALGOVERNMENT,AUTONOMOUSREGIONSANDWATERANDELECTRICPOWERPRESSFORADAPTINGTHEDEVELOPMENTOFELECTRICPOWERINDUSTRIALTECHNOLOGYANDINSURINGTHEERECTIONQUALITYOFPIPESOFTHERMALPOWERPLANT,THECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONPIPINGSECTIONDJ5679ISSUEDIN1979HADBEENREVISEDBYTHEMINISTRYTHENEWCODESHOULDBELOOKEDUPONASELECTRICPOWERTRADESTANDARDANDTHECODENUMBERISDL503194THESTANDARDISAPPROVEDANDISSUEDNOWANDWILLBEGOINTOEFFECTFROMOCT,1994ANDTHEOLDERVERSIONSHOULDBEABOLISHEDATTHESAMETIMEANYQUESTIONINTHEPERFORMINGSHOULDBENOTIFIEDTHECONSTRUCTIONCOOPERATINGDEPARTMENTOFTHEMINISTRYPLEASEAPR9,1994CONTENTS10GENERALRULES420GLOSSARY630CHECKINGOFPIPES,PIPEFITTINGS,PIPEACCESSORIESANDVALVES631GENERALREGULATIONS632CHECKINGOFPIES633CHECKINGOFPIPEFITTINGS734CHECKINGOFPIPEACCESSORIES735CHECKINGOFVALVES740PREPARATIONOFPIPES,PIPEFITTINGSANDPIPEACCESSORIES841GENERALREGULATIONS842ELBOWPIPE843PROCESSINGOFREELPIPES,PIPEFITTINGSANDPIPEACCESSORIES944PROCESSINGOFSUPPORTINGANDSUSPENDINGBRACKET1150INSTALLATIONOFPIPES1251GENERALREGULATIONS1252IINSTALLATIONOFHIGHPRESSUREPIPE1453INSTALLATIONOFMEDIUMANDLOWPRESSUREPIPE1554INSTALLATIONOFWATERDRAINAGEPIPE1555INSTALLATIONOFVALVEANDFLANGE1556INSTALLATIONOFSUPPORTINGANDSUSPENDINGBRACKET1660TESTANDCLEANOFPIPESYSTEM1761TIGHTNESSTESTOFPIPESYSTEM1762CLEANINGOFPIPESYSTEM1870ACCEPTANCEOFWORKS19APPENDIXATYPICALDATAINTHECONSTRUCTIONANDACCEPTANCEOFPIPESYSTEMINPOWERPLANT20APPENDIXBINSTALLATIONREGULATIONOFOXYGENPIPEANDACETYLENEPIPESYSTEM31SUPPLEMENTARYINSTRUCTION3210GENERALRULES101THECODEAPPLIESTOTHECONFIGURATION,CONSTRUCTIONANDACCEPTANCEOFFOLLOWINGPIPESOFTHERMALPOWERPLANTANDTHERMALPOWERNETWORK1011THEMAINSTEAMPIPESOF600MWORLOWERSUBCRITICALPARAMETERTHERMOELECTRICGENERATINGSETANDCORRESPONDINGREHEATINGSTEAMPIPESANDMAINWATERSUPPLYPIPES1012GENERALSTEAMANDWATERPIPES,THERMALPOWERNETWORKPIPESANDCOMPRESSEDAIRPIPESINTHERMALPOWERPLANT1013TEMPORARYPIPESUSEDINCONSTRUCTION102THECODEDOESNOTAPPLYTOTHEFOLLOWING1021CASTIRONPIPES1022REINFORCEDCONCRETEPIPES1023NONFERROUSTITANIUM,COPPERANDETCPIPES1024NONMETALPLASTICANDETCPIPES1025NONMETALLININGPIPES1026COMPOSITEMETALPIPES103FORTHESPECIALCONSTRUCTIONANDACCEPTANCEOFFOLLOWINGTYPESOFPIPES,REGULATIONSINCORRESPONDINGSECTIONOFTHECODEOFERECTIONANDACCEPTANCEFORELECTRICROWERCONSTRUCTIONSHOULDBEALSOCOMPLIEDBESIDESTHETECHNOLOGYREQUIREMENTSINTHISCODE1031ALLTYPESOFPIPESINTHESTEAMTURBINEANDELECTRICGENERATORBODY1032ALLTYPESOFPIPESINBOILERBODY,ANDPIPESOFFUMEEXHAUSTSYSTEM,VENTILATIONSYSTEM,COALSYSTEM,FUELSYSTEM,GASBURNINGSYSTEMANDDUSTREMOVALSYSTEM1033OILPIPESANDALLTYPESOFWATERTREATMENTPIPES1034ALLTYPESOFPIPESOFHYDROGENGENERATINGSYSTEMANDHYDROGENSUPPLYSYSTEM1035THERMALMETERPIPES1036OXYGENANDACETYLENEPIPES104EXCEPTTHESECTIONSWITHOTHERCONCRETESTIPULATIONSINCONSTRUCTIONCONTRACT,THEPROVISIONSINTHISCODEMUSTBEOBSERVEDINTHECONSTRUCTIONANDACCEPTANCEOFPIPESOFIMPORTEDTHERMOELECTRICGENERATINGSET105THEPIPINGINSTALLATIONOFPOWERPLANTMUSTBECARRIEDOUTBYPROFESSIONALCONSTRUCTIONTEAMWITHESSENTIALTECHNICALFORCE,CHECKINGMEANSANDMANAGEMENTLEVEL106THEPIPINGCONSTRUCTIONOFPOWERPLANTSHOULDBECARRIEDOUTACCORDINGTOTHEBASICCONSTRUCTIONPROGRAM,ANDFOLLOWINGCONDITIONSARENECESSARY1061DESIGNINGFILESANDOTHERTECHNOLOGYDOCUMENTSSHOULDBEFULLYREADY,ANDAJOINTCHECKUPMUSTHAVEBEENMADEFORCONSTRUCTIONDRAWINGS1062THECONSTRUCTIONORGANIZINGDESIGNANDCONSTRUCTIONPLANOFPIPINGPROJECTOFELECTRICPOWERPLANTSHOULDHAVEBEENCOMPILED,CHECKEDANDAPPROVED1063REALTECHNOLOGYCOMMUNICATIONANDREQUIREDTECHNICALTRAININGANDEXAMININGSHOULDHAVEBEENFINISHED1064LABORFORCE,MATERIALS,MACHINERIESANDCHECKINGMEANSSHOULDBECOMPLETEDONTHEWHOLE1065CONSTRUCTIONSHOULDSATISFYTHEDEMANDSOFENVIRONMENT1066WATER,POWERANDCOMPRESSEDAIRUSEDINCONSTRUCTIONSHOULDSATISFYTHEDEMANDSOFCONSTRUCTION107ACTIVENATIONALORTRADEORSPECIALTECHNICALSTANDARDSMUSTBECOMPLIEDFORTHEMANUFACTURINGQUALITYANDCHOOSINGOFPIPES,PIPEFITTINGSANDPIPEACCESSORIES108ACTIVESDJ68THEMAINTENANCEANDKEEPINGREGULATIONFORELECTRICPOWERBASICCONSTRUCTIONTHERMALPOWERDEVICESANDCORRESPONDINGADDITIONALREGULATIONSSHOULDBEOBSERVEDFORTHESTOREOFALLTYPESOFPIPES,PIPEFITTINGSANDPIPEACCESSORIES109ALLTYPESOFPIPESHOULDBECONSTRUCTEDACCORDINGTOTHEDESIGNDRAWINGS,ANDITSHOULDBESUBMITTEDTDESIGNINGUNITTOTREATINTERMOFRELEVANTREGULATIONIFTHEDESIGNSHOULDBEMODIFIEDORSUBSTITUTEMATERIALSHOULDBEADOPTED1010THERELEVANTREGULATIONINACTIVEDL5007THECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONWELDINGSECTIONOFTHERMALPOWERPLANTSHOULDALSOBEOBSERVEDINTHECUTTINGANDWELDINGOPERATIONFPIPESCONSTRUCTIONBESIDESTHERELEVANTREGULATIONSINTHISCODE1011REGULATIONSINSDJ245THECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONBOILERUNITSETSECTIONSHOULDBECOMPLIED1IRTHEHEATPRESERVATIONANDPAINTINGOFPIPESANDTHEPAINTINGOFPIPESHOULDBECARRIEDOUTACCORDINGTOTHEREGULATIONOFDL50IITHECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONSTEAMTURBINEUNITSETSECTION1012RELEVANTREGULATIONSOFACTIVEDL50091THESAFETYOPERATINGREGULATIONOFELECTRICPOWERCONSTRUCTIONTHERMALPOWERPLANTSECTIONMUSTBEOBSERVEDFORTHESAFETY,ENVIRONMENTANDFIREPROTECTIONINTHEPIPINGCONSTRUCTIONOFELECTRICPOWERPLANT20GLOSSARY201PIPEFITTINGSTHEGENERALDESIGNATIONOFPARTSANDELEMENTSWHICHCOMPOSINGPIPINGSYSTEMWITHPIPESTOGETHER,INCLUDINGELBOW,ELBOWPIPE,TEEPIPE,CONVERGINGTUBE,PIPECONNECTINGSADDLE,FLANGE,DEADEND,ENDPLATEANDETC202PIPEACCESSORIESEXTERNALSUPPORTINGPARTSOFPIPINGSYSTEM,INCLUDINGSUPPORTINGANDSUSPENDINGBRACKET,SHIM,SEALINGPARTS,FASTENINGPARTSANDSOON203ELBOWPIPEREFERSTOTHEPIPEWITHBENDINGAXIALLINE204ELBOWREFERSTOTHEELBOWPIPEWHICHBENDINGRADIUSISNOMORETHAN2D,ANDSTRAIGHTSECTIONISLESSTHAN10205MITERELBOWELBOWMADEUPOFTWOORMORESTRAIGHTPIPESECTIONSWHICHWELDINGTOGETHERINTHEPLANEOFEQUALBENDANGLEALSOCALLEDWELDINGELBOWORSHRIMPELBOW206CALCULATIONWALLTHICKNESSOFSTRAIGHTPIPETHEMINWALLTHICKNESSOFSTRAIGHTPIPEPLUSTHENEGATIVEDEVIATIONVALUEOFTHEWALLTHICKNESSOFSTRAIGHTPIPE207MONITORINGSECTIONPIPESECTIONUSEDTOMONITORCREEP,WHICHINSTALLEDONHORIZONTALSECTIONOFMAINSTEAMPIPESTHATDESIGNINGTEMPERATUREISABOVE4500C,ORREHEATINGHIGHTEMPERATURESTEAMPIPES208CREEPINGEXPANSIONMEASURINGPOINTEQUIPMENTSORMARKSTOMEASURETHECREEPDEFORMATIONOFPIPES,WHICHINSTALLEDONMOTORINGSECTIONPIPESORSTEAMPIPES209PIPECLASSIFICATIONELECTRICPOWERPLANTPIPESCANBECLASSIFIEDACCORDINGTODESIGNINGPRESSUREPASMAINPARAMETER,REFERSTOTABLE209TABLE209PIPECLASSIFICATIONPIPECLASSIFICATIONMAINPARAMETERHIGHPRESSUREPIPEP8MPAMEDIUMPRESSUREPIPE8MPAP16MPALOWPRESSUREPIPEP16MPANOTEREHEATINGSECTIONANDHEATINGSECTIONPIPESSHOULDBELOOKEDUPONASHIGHPRESSUREPIPES30CHECKINGOFPIPES,PIPEFITTINGS,PIPEACCESSORIESANDVALVES31GENERALREGULATIONS311QUALIFIEDCERTIFICATEOFMANUFACTURERMUSTBEPROVIDEDFORPIPES,PIPEFITTINGS,PIPEACCESSORIESANDVALVES,ANDCORRESPONDINGINDEXESSHOULDBEINCONCORDANCEWITHACTIVENATIONALORTRADETECHNICALSTANDARDS,312SPECIFICATION,MATERIALANDTECHNICALPARAMETERMUSTBECHECKEDACCORDINGTOTHEDESIGNREQUIREMENTSPRIORTOTHEUSINGOFANYPIPE,PIPEFITTING,PIPEACCESSORYANDVALVE313APPEARANCEINSPECTIONISREQUIREDPRIORTOTHEUSINGOFANYPIPE,PIPEFITTING,PIPEACCESSORYANDVALVE,ANDTHEAPPEARANCEDEMANDSAREASFOLLOWING3131WITHOUTANYDEFECTSSUCHASCRACK,SHRINKAGECAVITY,INCLUDEDSLAG,ADHERINGSAND,FOLDING,MISSINGWELDING,COLDLAPANDSOON3132THESURFACESHOULDBESMOOTHNESSWITHOUTANYSHARPSCRATCHES3133CONCAVEDEPTHSHOULDNOTBEMORETHAN15MM,ANDTHEMAXDIMENSIONSHOULDNOTBE5MORETHANTHEPIPEPERIMETER,ANDNOTBEMORETHAN40MM,314SPECTRUMREEXAMININGISREQUIREDANDMATERIALMARKSSHOULDBEMADEPRIORTOTHEUSINGOFPIPES,PIPEFITTINGSPIPEACCESSORIESANDVALVESWHICHMADEOFMEDIUMANDLOWALLOYSTEEL32CHECKINGOFPIES321FOLLOWINGITEMSMUSTBETODETERMINEIFTHEYAREINAC0DANCEWITHACTIVENATIONALORTRADETECHNICALSTANDARDSPRIORTOTHECONSTRUCTIONOFPIPESWHICHDESIGNINGPRESSUREISMORETHANOREQUALTO16MPA3211ANALYSISRESULTSOFCHEMICALCOMPOSITION3212TESTRESULTSOFMECHANICALPROPERTYTENSILESTRENGTH,YIELDSTRENGTHANDRATIOOFELONGATION3213TESTRESULTSOFIMPACTDUCTILITYFORHIGHPRESSUREALLOYSTEELPIPESWHICHWALLTHICKNESSISMORETHANOREQUALTO12MM3214HEATTREATMENTCONDITIONORMETALLURGICALPHASEANALYSISRESULTSOFALLOYSTEELPIPES322WELDINGSEAMCHECKINGREPORTMUSTBEEXAMINEDPRIORTOTHEUSINGOFSEAMEDPIPEWHICHDESIGNINGPRESSUREISMORETHAN01MPA323LOCALDEFECTSSUCHASSCRATCHES,CONCAVECAVITIESANDCORRODESONPIPESURFACESHOULDBECHECKEDPIPEWALLTHICKNESSWHICHHADBEENTREATEDSHOULDNOTBELESSTHANTHECALCULATIONWALLTHICKNESSOFSTRAIGHTPIPE,ANDTHECHECKINGREPORTMUSTBERECORDEDANDSUBMITTED324THICKNESSOFNOLESSTHAN3CROSSSECTIONSSHOULDBEMEASUREDANDCHECKEDFORMEDIUMORLOWALLOYSTEELPIPESWHICHUSEDASHIGHPRESSURE,ANDTHERECORDINGISREQUIRED325QUALIFIEDSTEELPIPESSHOULDBESTOREDACCORDINGTOTHEIRMATERIALSANDSPECIFICATIONS,TOAVOIDCORROSION33CHECKINGOFPIPEFITTINGS331FOLLOWINGITEMSMUSTBECHECKEDTODETERMINEIFTHEYAREINACCORDANCEWITHACTIVENATIONALORTRADETECHNICALSTANDARDSPRIORTOTHEPIPEFITTINGSUSEDINTHECONSTRUCTIONOFMEDIUMORHIGHPRESSUREPIPES3311ANALYSISRESULTSOFCHEMICALCOMPOSITION3312HEATTREATMENTCONDITIONORMETALLURGICALPHASEANALYSISRESULTSOFALLOYSTEELPIPES3313NONDESTRUCTIVEFLAWDETECTIONRESULTSOFHIGHPRESSUREPIPEFITTINGS332SEALINGSURFACEOFFLANGESHOULDBESMOOTHANDCLEANWITHOUTRADIALGROOVE,ANDAIRCAVITY,CRACK,BURROROTHERDEFECTSTHATCANREDUCESTRENGTHANDCONNECTINGRELIABILITYAREFORBIDDEN333FLANGESWITHCONCAVE/CONVEXSURFACEORCONCAVE/CONVEXRINGSHOULDBESNAPPEDNATURALLY,ANDTHEHEIGHTOFCONCAVESURFACESHOULDNOTBELESSTHANTHEDEPTHOFNOTCH334SUPPORTINGAREAOFCONNECTINGBOLTSONFLANGEENDFACESHOULDBEPARALLELTOTHEJUNCTIONSURFACEOFFLANGE,TOINSUREEVENFORCEACTEDONFLANGEENDSURFACEWHENCONNECTING335DIMENSIONSOFEACHPARTSHOULDBECHECKEDACCORDINGTOTHEDESIGNDRAWINGANDEXAMINEDTODETERMINATEITSCONFORMITYWITHFLANGEONDEVICETOBECONNECTED,TOENSUREPROPERCONNECTION34CHECKINGOFPIPEACCESSORIES341THREADOFBOLTSANDNUTSSHOULDBEUNDAMAGEDWITHOUTANYDEFECTSSUCHASSCRATCHES,BURRSANDETCANDTHEMATCHINGBETWEENBOLTANDNUTSHOULDBEINGOODCONDITIONWITHOUTLOOSENORBLOCKING342EACHALLOYSTEELBOLT,WHICHDESIGNINGTEMPERATUREISABOVE430OC,ANDDIAMETERISMORETHANOREQUALTOM30,SHOULDBENUMBEREDANDITSHARDNESSSHOULDBECHECKED,ANDUNQUALIFIEDONEMUSTNOTBEUSED343PADMATERIALOFFLANGESHOULDBEINCONCORDANCEWITHTHEDESIGNINGREQUIREMENTTABLEA5INAPPENDIXACANBEUSEDTOSELECTMATERIALINCASEOFNOCONCRETEREQUIREMENTPROVIDED344ASBESTOSRUBBERPADSHOULDBESOFTANDPLIANT,WITHOUTANYAGINGORDELAMINATINGANDANYDEFECTSUCHASBUCKLEANDWRINKLEISFORBIDDENONSURFACE345VISUALINSPECTIONSHOULDBEMADEFORTHESURFACEOFMETALSHIMWITHLEVELINGRULE,THEGOODCONTACTISNECESSARYANDDEFECTSSUCHASCRACK,BURR,RUSTORCOARSEPROCESSINGARENOTALLOWEDANDITSHARDNESSSHOULDBELESSTHANTHEFLANGES346RADIALSCRATCH,LOOSENANDOTHERDEFECTSAREALLNOTALLOWEDFORTHECLADDINGMETALANDWINDINGSHIM347ASSEMBLINGDIMENSIONANDWELDINGTYPEOFSTEELSTRUCTUREOFPIPESUPPORTINGANDSUSPENDINGBRACKETSHOULDBECONCORDANCEWITHTHEREGULATIONOFTHECODE44348WORKINGSURFACEOFSLIDINGBRACKETSHOULDBESMOOTHANDMOVEFLEXIBLYWITHOUTANYBLOCKING349SPRINGOFPIPESUPPORTINGANDSUSPENDINGBRACKETSHOULDBECHECKEDACCORDINGTOTHEARTICLE444AND445OFTHECODE35CHECKINGOFVALVES351FOLLOWINGEXAMININGISNECESSARYPRIORTOTHEINSTALLATIONOFALLTYPESOFVALVES3511IFPADDINGMATERIALISINCONCORDANCEWITHTHEREQUIREMENTOFDESIGN,ANDIFPADDINGMETHODISCORRECTORNOTSEALINGPADDINGMATERIALCANBESELECTEDACCORDINGTOTHETABLEA6INAPPENDIXAINCASEOFNODESIGNREQUIREMENTPROVIDED3512WHETHERCORROSIONOCCURSONTHEVALVESTEMWHEREVERPADDINGSEALING3513IFTHEACTIONOFSWITCHESAREFLEXIBLEANDTHEINDICATIONSAREALLCORRECT3514OBVIOUSMANUFACTURINGDEFECTISFORBIDDENONTHEAPPEARANCEOFCASTINGVALVE352TIGHTNESSCHECKINGMUSTBEMADEPRIORTOTHEINSTALLATIONOFVALVEUSEDASCLOSEDCIRCUITELEMENTACTINGASISOLATION,TOCHECKTHETIGHTNESSOFJOINTSURFACESBETWEENVALVESEATANDVALVECORE,VALVECOVERANDPADDINGCHAMBERWATERPRESSURE,WHICH125TIMESMORETHANPRESSUREMARKEDONNAMEPLATE,SHOULDBEAPPLIEDINTHETIGHTNESSTESTOFVALVE353NOLESSTHAN10ATLEAST1VALEINTHESAMEBATCHTHESAMEMANUFACTURER,SPECIFICATIONANDMODELMUSTBECHECKEDBYSAMPLINGFORTIGHTNESSTESTFORLOWPRESSUREVALVEADDITIONAL20SHOULDBECHECKEDBYSAMPLINGINCASEOFSOMEONEISUNQUALIFIED,ANDIFSOMEONEDOESSTILLNOTPASS,ALLVALVESSHOULDBECHECKEDONEBYONETIGHTNESSTESTMUSTBEDONEONEBYONEFORALLVALVESUSEDONHIGHPRESSUREPIPE354TIGHTNESSTESTOFSEALINGSURFACEOFVALVECORECANBECARRIEDOUTWITHCOLORPAINTINGMETHODFORSAFETYVALVESANDVALVESWHICHNOMINALPRESSURENOMORETHAN06MPAANDINSIDENOMINALDIAMETERNOLESSTHAN800MMWATERPRESSUREMETHODCANBEREPLACEBYOILORWATERPENETRATIONMETHODTOPERFORMTIGHTNESSTESTFORLARGECALIBERWELDINGVALVEWHICHINSIDENOMINALDIAMETERISMORETHANOREQUALTO600MM355PAINTSUCHASGREASEARESTRICTLYPROHIBITEDONTHEJOINTSURFACEPRIORTOTHETIGHTNESSTESTOFVALVE356METHODOFWATERPRESSURETIGHTNESSTESTMUSTBEINCONCORDANCEWITHTHEREQUIREMENTOFVALVEMANUFACTURERINTHETEST,WATERSHOULDBEFILLEDINFROMTHEUPSTREAMOFVALVEFLAPFORSHUTOFFVALVE,ANDALLSEALINGSURFACESHOULDBECHECKEDWITHVALVECLOSEDFORGATEVALVE357ALLQUALIFIEDVALVESSHOULDBEKEPTWELLACCORDINGTOTHEIRCLASSIFICATIONAFTERTIGHTNESSTEST,ANDANYWATERREMINDINGINCHAMBERMUSTBEREMOVECOMPLETELY358DISMOUNTINGCHECKINGISNECESSARYFORFOLLOWINGVALVES3581VALVEWHICHDESIGNINGTEMPERATUREISMORETHANOREQUALTO4503582SAFETYVALVEANDTHROTTLEVALVE3583UNQUALIFIEDVALVEINTHETIGHTNESSTEST359ANYDIRTANDFOREIGNMATERIALMUSTBEREMOVEDTHOROUGHLYPRIORTODISMOUNTINGVALVE,OROPENING/CLOSINGOPERATIONANDDISMOUNTINGAREFORBIDDENDISMOUNTINGORDERSPECIFIEDBYMANUFACTURERMUSTBEOBSERVEDWHENVALVEWITHSPECIALSTRUCTUREISBEENDISMOUNTED,TOAVOIDDAMAGINGPARTSORHAMPERINGPERSONNELSAFETY3510FOLLOWINGCHECKINGISNECESSARYFORVALVEDISMOUNTED35101SPECTRUMRECHECKINGSHOULDBECARRIEDOUTFORINTERIORPARTSOFALLOYSTEELVALVENOMARKSNOTEDONPARTSISALLOWED,WHILECHECKRESULTSMUSTBERECORDED35102WHETHERTHEJOINTBETWEENVALVESEATANDVALVECASEISFIRM,WITHOUTLOOSEN35103WHETHERTHEJOINTSURFACEBETWEENVALVESTEMANDVALVESEATISCOINCIDE,ANDWITHOUTDEFECTS35104WHETHERTHECONNECTIONBETWEENVALVESTEMANDVALVECOREISFLEXIBLEANDRELIABLE35105WHETHERTHEVALVEISBENDANDCORROSION,ANDTHETIGHTNESSDEGREEOFMATCHINGBETWEENVALVESTEMANDPADDINGMATERIALCOVERISSUITABLE,ANDTHEREARESOMEDEFECTSSUCHASBROKENTHREADONTHETHREADOFVALVESTEM35106THECONTACTINGCONDITIONOFVALVECOVERFLANGESURFACE35107OPENING/CLOSINGSTROKEANDENDPOSITIONMUSTBECHECKEDFORTHROTTLEVALVE,ANDMARKSHOULDBEMADEASFARASPOSSIBLE3511FOLLOWINGQUALITYREQUIREMENTSSHOULDBESATISFIEDAFTERTHEDISMOUNTINGCHECKINGANDELIMINATINGDEFECTSHADBEENFINISHED35111MATERIALOFALLOYSTEELSHOULDMEETTHEREQUIREMENTOFDESIGN35112CORRECTASSEMBLY,FLEXIBLEACTION,ANDTHEINDICATINGPOSITIONOFOPENINGINDICATORSHOULDBEACCURATE35113SPECIFICATIONANDQUALITYOFEACHPADANDPADDINGMATERIALSHOULDBEINCONCORDANCEWITHTECHNICALREQUIREMENT35114PADDINGMATERIALSHOULDBEFILLEDCORRECTLY,ANDTHEINCLINEDMOUTHPIECESHOULDBEMADE,ANDMOUTHPIECEOFEACHLAYERSHOULDBESTAGGEREDTIGHTNESSMUSTBEENSUREDAFTERTHECOMPACTNESSOFPADDINGMATERIALANDTHEMOTIONOFVALVESTEMSHOULDNOTBEHAMPERED3512FLOWCHANNELOFVALVEOFOILSYSTEMSHOULDBECLEANEDTOREMOVEANYMOLDINGSAND,PAINTANDETC,ANDOILPROOFPACKINGSETANDSHIMSHOULDBEREPLACED3513WHENREASSEMBLING,SCREWSOFVALVECOVERCANONLYBEFASTENEDWHENVALVEFLAPISATOPENINGPOSITIONAFTERTHEDISMOUNTINGCHECKINGOFGATEVALVEANDSHUTOFFVALVEHASFINISHED3514TIGHTNESSTESTISREQUIREDAFTERTHEREASSEMBLYOFVALVE3515DISMOUNTINGTESTANDTIGHTNESSCHECKINGCANONLYBEOMITTEDIFMANUFACTURERCANPROVIDETHEQUALITYGUARANTEEOFPRODUCTSORQUALIFIEDANDOPERATINGCERTIFICATEISPROVIDED,ORCHECKSHOULDBEDONEACCORDINGTOTHEREGULATIONSINTHISCHAPTER3516FOROPERATINGMECHANISMANDDRIVEMECHANISM,REQUIREDCHECKANDADJUSTMENTMUSTBECARRIEDOUTACCORDINGTODESIGNINGREQUIREMENT,TOMAKETHEMACTFLEXIBLYANDINDICATEACCURATELY40PREPARATIONOFPIPES,PIPEFITTINGSANDPIPEACCESSORIES41GENERALREGULATIONS411PREPARATIONOFPIPEANDTHEPROCESSINGOFSUPPORTINGANDSUSPENDINGBRACKETSHOULDBEINACCORDANCEWITHDESIGNDRAWINGSANDRELATIVEREGULATIONSINSTANDARD412MATERIALSANDSPECIFICATIONSOFSTEELPIPES,STEELPLATESANDOTHERSHAPEDSTEELSSHOULDBEINACCORDANCEWITHDESIGNREQUIREMENT413RELEVANTREGULATIONSINACTIVEDL5007THECODEOFERECTIONANDACCEPTANCEFORELECTRICPOWERCONSTRUCTIONWELDINGSECTIONOFTHERMALPOWERPLANTMUSTBEOBSERVEDWHENCUTTINGPIPE414ORIGINALMARKSSHOULDBETRANSFERREDINTIMEAFTERHIGHPRESSURESTEELPIPEANDALLOYSTEELPIPEHADBEENCUTOFF42ELBOWPIPE421PIPEWITHPOSITIVETOLERANCEOFWALLTHICKNESSSHOULDBEADOPTEDWHENPIPEPROCESSINGINCASEOFNOTHICKENINGPIPECHOSEN422BENDRADIUSOFELBOWPIPEMUSTBEINACCORDANCEWITHDESIGNREQUIREMENTCORRESPONDINGREGULATIONSINTRADESTANDARDDL/T515ELBOWPIPEUSEDINPOWERSTATIONMUSTBEOBSERVEDIFNODESIGNREQUIREMENTGIVENFORTHEMINBENDRADIUSOFELBOWPIPE423FOLLOWINGREGULATIONSMOSTBEOBSERVEDWHENELBOWPIPEISHEATEDWITHMEDIUMFREQUENCYMETHOD4231THEHEATINGTEMPERATURESHOULDBE8501000“CWHENLOWCARBONSTEELISBENTWATERINJECTIONCOOLINGCANBEADOPTEDINCASEOFPIPEWALLTHICKNESSISNOMORETHAN25MM,OTHERWISE,FORCEDAIRCOOLINGSHOULDBEADOPTED,ANDHEATTREATMENTISNOTNECESSARY4232HEATINGTEMPERATUREOFBACKARCOFPIPEMUSTNOTEXCEED900CWHENBENDINGALLOYSTEELPIPE,ANDFORCEDAIRCOOLINGSHOULDBEUSEDNORMALIZATIONANDTEMPERTREATMENTISREQUIREDAFTERBENDISFINISHED4233WHENBENDINGNEWTYPEOFSTEELPIPE,TESTMUSTBEDONEFORTHEMAXDEFORMATIONOFBACKARCOFSTEELPIPE,ANDBENDINGPROCESSCANONLYBEESTABLISHEDTOBENDTHEPIPEAFTERITHADBEENCONFIRMEDTHATNODEFECTSSUCHASINTERCRYSTALLINEFRACTUREEXISTS424CHECKBYSAMPLINGSAMPLECANBEOBTAINATTHEPLACEOFBENDINGSECTIONISREQUIREDAFTERHEATTREATMENTISENDEDFORTHEINITIALUSEOFNEWSTEELTYPE,ORCOMMONSTEELTYPEWHICHHEATTREATMENTSPECIFICATIONHADBEENCHANGED,TOOBTAINDATASPECIFIEDINITEM2,3AND4INARTICLE321OFTHISCODE425EXTERNALANDINTERNALSURFACEMUSTBECLEANEDAFTERTHEPREPARATIONOFBENDPIPE426DATASUCHASOUTOFROUNDNESS,WAVEDEGREE,ANGLEDEVIATIONANDREDUCINGVALUEOFWALLTHICKNESSMUSTBEINCONCORDANCEWITHFOLLOWINGRULESAFTERTHEPREPARATIONOFBENDPIPE4261OUTOFROUNDN