BS 1212-2-1990 浮子阀.第2部分隔膜型浮子阀(铜合金阀体)(不含浮子)

BRITISHSTANDARDBS1212-2:1990Floatoperatedvalves—Part2:Specificationfordiaphragmtypefloatoperatedvalves(copperalloybody)(excludingfloats)UDC621.646.618:621.646.38Licensedcopy:PONTYPRIDDCOLLEGE,13/02/2008,UncontrolledCopy,©BSIBS1212-2:1990ThisBritishStandard,havingbeenpreparedunderthedirectionoftheBuildingServicesStandardsCommittee,waspublishedundertheauthorityoftheBoardofBSIandcomesintoeffecton29June1990©BSI01-2000FirstpublishedSeptember1970FirstrevisionJune1990ThefollowingBSIreferencesrelatetotheworkonthisstandard:CommitteereferenceSEB/2Draftforcomment83/11865DCISBN0580158462CommitteesresponsibleforthisBritishStandardThepreparationofthisBritishStandardwasentrustedbytheBuildingServicesStandardsCommittee(SEB/-)toTechnicalCommitteeSEB/2uponwhichthefollowingbodieswererepresented:AssociationofManufacturersofDomesticElectricalAppliancesAssociationofManufacturersofDomesticUnventedSupplySystemsEquipment(MODUSSE)AssociationofWaterOfficersLtd.BritishBathManufacturers’AssociationBritishGasCorporationBritishNon-ferrousMetalsFederationBritishPlasticsFederationBritishValveManufacturers’AssociationLtd.BuildersMerchantsFederationConsumerStandardsAdvisoryCommitteeofBSICopperTubeFittingsManufacturers’AssociationCouncilofBritishCeramicSanitarywareManufacturersDepartmentoftheEnvironment(BuildingResearchEstablishment)DepartmentoftheEnvironment(PropertyServicesAgency)DepartmentoftheEnvironment(WaterDirectorate)DepartmentofTradeandIndustry(NationalWeightsandMeasuresLaboratory)InstituteofClerksofWorksofGreatBritainInc.InstituteofPlumbingInstitutionofGasEngineersInstitutionofPublicHealthEngineersInstitutionofWaterEngineersandScientistsMetalSinkManufacturers’AssociationNationalAssociationofPlumbing,HeatingandMechanicalServicesContractorsNationalBrassfoundryAssociationRoyalInstituteofBritishArchitectsSocietyofBritishGasIndustriesSouthLondonConsortiumWaterAuthorities’AssociationWaterCompanies’AssociationAmendmentsissuedsincepublicationAmd.No.DateofissueCommentsLicensedcopy:PONTYPRIDDCOLLEGE,13/02/2008,UncontrolledCopy,©BSIBS1212-2:1990©BSI01-2000iContentsPageCommitteesresponsibleInsidefrontcoverForewordiiiSection1.General1Scope12Definition13Designationforordering14Marking1Section2.Materials5Qualityandfinish26Plastics27Castings28Hotstampings29Mouldings210Machining2Section3.Design,constructionanddimensions11General412Screwthreads413Inletconnection414Backnuts415Bodies416Bodycouplingnuts417Backplatenuts418Backplates519Backplateplungers520Seats521Diaphragms522Levers523Floatadjustersandthumbscrews524Splitcotterpins525Dischargearrangement5Section4.Performance26Hydraulicpressureandshut-off627Backnutdistortion628Backflowprevention629Flow630Hydraulicpressureondischargearrangement6AppendixAMethodoftestforshut-offwhenassembledwithappropriatefloat17AppendixBMethodoftestfordistortionofsizeplasticsbacknuts17AppendixCMethodoftestforbackflowprevention17AppendixDMethodoftestforflow18AppendixEMethodoftestforeffectofhydraulicpressureondischargearrangement18Figure1—Sectionoftypicalsize½diaphragmtypefloatoperatedvalve6Figure2—Inletshanks8Figure3—Inletelbows9Figure4—Backnuts10Licensedcopy:PONTYPRIDDCOLLEGE,13/02/2008,UncontrolledCopy,©BSIBS1212-2:1990ii©BSI01-2000PageFigure5—Body11Figure6—Bodycouplingnuts12Figure7—Backplatenuts12Figure8—Backplate13Figure9—Backplateplunger13Figure10—Seatsandjointringforseats14Figure11—Diaphragm15Figure12—Lever16Figure13—Floatadjusterandthumbscrew16Figure14—Typicalarrangementofapparatusforbackflowpreventiontest19Figure15—Typicalarrangementofapparatusforflowtest19Table1—Materials3Table2—Seats15Table3—Seatandfloatcombination17PublicationsreferredtoInsidebackcoverLicensedcopy:PONTYPRIDDCOLLEGE,13/02/2008,UncontrolledCopy,©BSIBS1212-2:1990©BSI01-2000iiiForewordThisPartofBS1212hasbeenpreparedunderthedirectionoftheBuildingServicesStandardsCommitteeandspecifiesrequirementsfordiaphragmtypefloatoperatedvalves(excludingfloats).ItsupersedesBS1212-2:1970,whichiswithdrawn.ThenewfeaturesinthisPartofBS1212includethefollowing:a)thepossibleproductionofcertaincomponentsfromplasticsmaterials;b)aseatnumberingsystem;c)abottomentryinletconnectionanditsassociatedinletelbow,withadjustablestay;d)arecognitionofthegreaterliftingeffortofplasticsfloatsovercopperfloatsofequivalentsize;e)atestforplasticsbacknutstrength,inlinewithBS1212-3;f)arecognitionofcurrentmanufacturingpracticebydeletionofreferencetotheuseofagatetippedseats;g)arecognitionofmethodsofattachmentofthedischargearrangementscurrentlyusedinfloatvalvesmanufacturedinaccordancewithBS1212-3,andatesttoverifytheireffectiveness;h)amodificationofthemethodofdimensioningsomecomponentstoensuretheleverdoesnotriseabovethehorizontalatvalveclosure;j)thedimensionalalignmentofthebodyinletconnectionwithBS1212-1,whichnowrequiresonlyoneseatjointringforeitherplasticsormetalseats.FloatoperatedvalvescomplyingwithBS1212-2andcarryingtheKitemarkareautomaticallyeligibleforlistingintheWaterResearchCentreFittingsSchemeDirectoryofWaterFittings.ThisPartofBS1212hasbeenrevisedinmetricterms,exceptforcertainthreadsizesandpipeth