BS 6755-2 1987

BRITISHSTANDARDBS6755-2:1987Reprinted,incorporatingAmendmentNo.1andNo.2Testingofvalves—Part2:Specificationforfiretype-testingrequirementsUDC621.646[620.1:532.11]:614.84LicensedCopy:InstituteOfTechnologyTallaght,InstituteofTechnology,SunJul1509:08:26GMT+00:002007,UncontrolledCopy,(c)BSIBS6755-2:1987ThisBritishStandard,havingbeenapprovedunderthedirectionofthePipingSystemsComponentsStandardsCommittee,waspublishedundertheauthorityoftheBoardofBSIandcomesintoeffecton31July1987©BSI12-1998ThefollowingBSIreferencesrelatetotheworkonthisstandard:CommitteereferencePSE/7Draftforcomment86/73183DCISBN0580160610CommitteesresponsibleforthisBritishStandardThepreparationofthisBritishStandardwasentrustedbythePipingSystemsComponentsStandardsCommittee(PSE/-)toTechnicalCommitteePSE/7,uponwhichthefollowingbodieswererepresented:AmalgamatedUnionofEngineeringWorkersAssociatedOfficesTechnicalCommitteeAssociationofBronzeandBrassFoundersBritishChemicalEngineeringContractors’AssociationBritishCompressedGasesAssociationBritishFluidPowerAssociationBritishFoundryAssociationBritishGasplcBritishMaritimeTechnologyBritishShipbuildersBritishValveManufacturers’AssociationLtd.CopperDevelopmentAssociationCopperTubeFittingsManufacturers’AssociationLtd.ElectricitySupplyIndustryinEnglandandWalesEnergyIndustriesCouncilEngineeringEquipmentandMaterialsUsers’AssociationGAMBICA(BEAMALtd.)GeneralCouncilofBritishShippingHealthandSafetyExecutiveInstituteofBritishFoundrymenInstitutionofChemicalEngineersInstitutionofGasEngineersInstitutionofMechanicalEngineersInstitutionofWaterEngineersandScientistsSocietyofBritishGasIndustriesSteelCastingResearchandTradeAssociationWaterAuthoritiesAssociationWaterCompaniesAssociationAmendmentsissuedsincepublicationAmd.No.DateofissueComments6272November19906712June1991IndicatedbyasidelineinthemarginLicensedCopy:InstituteOfTechnologyTallaght,InstituteofTechnology,SunJul1509:08:26GMT+00:002007,UncontrolledCopy,(c)BSIBS6755-2:1987©BSI12-1998iContentsPageCommitteesresponsibleInsidefrontcoverForewordiiSection1.General1Scope12Definitions1Section2.Conditionsoftest3Directionandconditionsforvalvestobetested24Pressurereliefprovision2Section3.Performance5General36Through-seatleakage(hightestpressure)duringburnperiod37Externalleakage(hightestpressure)duringburnandcool-downperiods38Through-seatleakage(lowtestpressure)aftercool-down39Externalleakage(lowtestpressure)aftercool-down310Operability311Externalleakageinfullyopenposition3AppendixAFiretestmethod4AppendixBQualificationofvalvesbyrepresentativesizeandpressurerating10AppendixCAdditionalinformationtobeincludedinthetestreport12Figure1—Recommendedsystemsforfiretype-testingofvalves(schematic)5Figure2—Calorimetercubedesignanddimensions6Figure3—LocationofcalorimetercubesandflameenvironmentthermocouplesforDN150(NPS6)andsmallersizevalves8Figure4—LocationofcalorimetercubesandflameenvironmentthermocouplesforvalveslargerthanDN150(NPS6)8Table1—TestpressuresforPNandClassratedvalves7Table2—Othervalvesqualifiedaccordingtosize11Table3—OthervalvesqualifiedbyPNrating11Table4—OthervalvesqualifiedbyClassrating11PublicationsreferredtoInsidebackcoverLicensedCopy:InstituteOfTechnologyTallaght,InstituteofTechnology,SunJul1509:08:26GMT+00:002007,UncontrolledCopy,(c)BSIBS6755-2:1987ii©BSI12-1998ForewordThisBritishStandardhasbeenpreparedunderthedirectionofthePipingSystemsComponentsStandardsCommitteeandispublishedintwoParts:—Part1:Specificationforproductionpressuretestingrequirements;—Part2:Specificationforfiretype-testingrequirements.ThisPartofBS6755embodiesthetechnicalcontentofAPISpecification6FAforfiretype-testingofvalves,includingvalvestoAPISpecification6D,andofAPIStandard607,publishedbytheAmericanPetroleumInstitute(API),butdiffersinpresentation.Itcoverstherequirementsfortestingandmethodoftestforevaluatingtheperformanceofvalveswhenexposedtodefinedfireconditions.Theperformancerequirementsareintendedtoestablishlimitsofacceptabilityofavalveregardlessofsize,nominalpressure(PN)orClassrating.Theburnperiodhasbeenestablishedonthebasisthatitrepresentsthemaximumtimerequiredtoextinguishmostfires.Firesoflongerdurationareconsideredtobeofamajormagnitudewithconsequencesgreaterthanthoseanticipatedinthetest.PermissionfromAPItoincorporatetherelevanttechnicalcontentofAPIStandard607andAPISpecification6FAintothisPartofBS6755isgratefullyacknowledged.ItisintendedthatthisPartofBS6755willeventuallysupersedethefiretestspecifiedinclause21anddescribedinappendixAofBS5146-1:1974.However,toallowfortheconstructionoffiretestingequipmentandforvalvemanufacturerstoobtainapprovalforvalvesmadetoafiretype-testdesignthefollowingapplies.a)Foraperiodof3yearsfromthepublicationofthisstandard,valvesofexistingdesignmaybetestedinaccordancewitheither:1)thisPartofBS6755;or2)appendixAofBS5146-1:1974.b)Valvessubmittedforfirsttimefiretype-testingstartingfromadate1yearafterpublicationofthisPartofBS6755shouldbetestedinaccordancewiththisstandard.c)ThreeyearsafterpublicationofthisPartofBS6755,thefiretestingrequirementsgiveninBS5146-1:1974willbewithdrawn.Itisintendedt