BS 1212-1-1990 Float operated valves. Specificatio

BS1212:Part1:1990UDC621.646.618:621.646.2-314.1:669.35’50BritishStandardsInstitution.NopartofthispublicationmaybephotocopiedorotherwisereproducedwithoutthepriorpermissioninwritingofBSIBritishStandardFloatoperatedvalvesPart1.Specificationforpistontypefloatoperatedvalves(copperalloybody)(excludingfloats)RobinetsaflotteurPartie1.Robinetsaflotteurdetypepiston(corpsenalliagedecuivre)(aI’exclusiondesflotteurs)-SpecificationsSchwimmerventiIeTeil1.Kolbenschwimmerventile(mitGehauseausKupfer)(ausgenommenSchwimmer)BritishStandardsInstitutionLicensedcopy:PONTYPRIDDCOLLEGE,13/02/2008,UncontrolledCopy,©BSI~~~~~BS1212:Part1:1990ForewordThisPartofBS1212hasbeenpreparedunderthedirectionoftheBuildingServicesStandardsCommitteeandspecifiesrequirementsforpistontypefloatoperatedvalves(exclud-ingfloats).ItsupersedesBS1212:Part1:1953,whichiswithdrawn.ThenewfeaturesinthisPartofBS1212includethefollowing:(a)thepossibleproductionofcertaincomponentsfromplasticsmaterials;(b)anextensionoftherangeofsizesofplasticsseats;(c)aseatnumberingsystem;(d)abottomentryinletconnectionanditsassociatedinletelbow,withadjustablestay;(e)arecognitionofthegreaterliftingeffortofplasticsfloatsovercopperfloatsofequivalentsize;(f)thesupplyofsize3/8andsize'12leverswithadownturnportionfittedwithafloatadjusterandthumbscrew;(9)afurthermethodofproductionfortwopiecelevers(h)atestforplasticsbacknutstrength,inlinewithBS1212:Part3;(j)atestforplasticslocknutstrength;(k)arecognitionofcurrentmanufacturingpracticebydeletionofreferencetotheuseofagatetippedseats.DuetothefactthatvalvescoveredbythisPartofBS1212donotprovidetheappropriatebacksiphonageprotectionrequiredbytheWaterByelaws,itisrecommendedinthecaseofnominalsizevalvesthatavalvecoveredbyoneoftheotherPartsofBS1212beusedforapplicationswherebacksiphonageprotectionisrequired.Alternatively,avalvecoveredbyBS1212:Part1canbeusedinthesecasesifasuitableprotectivedeviceisconnectedtothefeedpipertothevalve.Fornominalsize%andabove,suchadeviceshouldbeusedwheneverbacksiphonageprotectionisrequired.AdviceonsuitableprotectivedevicesisgivenintheWaterResearchCentrepublication'WaterFittingsandMaterialsDirectory'andinBS6700.ThisPartofBS1212hasbeenrevisedinmetricterms,exceptforcertainthreadsizesandpipethreaddesignationswhichareretainedinimperialsizestoaccordwithBS2779.CompliancewithaBritishStandarddoesnotofitselfconferimmunityfromlegalobligations.Licensedcopy:PONTYPRIDDCOLLEGE,13/02/2008,UncontrolledCopy,©BSIBS1212:Part1:1990ContentsForewordCommitteesresponsiblePageInsidefrontcoverBackcoverSpecificationSectionone.General1Scope2Definition3Designationforordering4MarkingSectiontwo.Materials5Qualityandfinish6Plastics7Castings8Hotstampings9Mouldings10MachiningSectionthree.Design,constructionanddimensions11General12Screwthreads13Inletconnection14Backnuts15Bodies16Bodycouplingnuts17Bodyendcaps18Pistonsandpistonwashers19Seats20Levers21Locknutsforlevers22Floatadjustersandthumbscrews23SplitcotterpinsSectionfour.Performance24Hydraulicpressureandshut-off25Backnutdistortion26Locknutdistortion27MechanicalstrengthofleversAppendicesAMethodoftestforshut-offwhenassembledwithappropriatefloat22223333335566666677788999930BMethodoftestfordistortionofsize'/zplasticsbacknutsCMethodoftestfordistortionofplasticslocknutsDMethodoftestformechanicalstrengthofleversEDischargeofwaterthroughpistontypefloatoperatedvalvesTables1Materials2Body,seatandfloatcombination3Sideentryinletshankandinletforconnectionto12mmand15mmcoppertube4Type(a)backnuts(integralflange)5Type(b)backnuts(spigoted)6Type(c)backnuts(fixedflange)7Bodies8Bodycouplingnuts9Bodyendcap10Pistonsandpistonwashers11Seatsandjointringforseats12Seatnumbers13Levers14Testloadsforlevers15ComputedflowthroughseatorificesFigures1Sectionoftypicalsize'/zpistontypefloatoperatedvalvewithdetailofinletandalternativeleverarm2Inletshanks3Inletelbows4Backnuts5Bodies6Bodycouplingnuts7Bodyendcap8Pistonsandpistonwashers9Seatsandjointringforseats10Leversandsocketforsolderedjointfortwopiecelevers11Floatadjuster,thumbscrewandsplitcotterpinPage3030303045121515151719202125252730329111314161920212327291Licensedcopy:PONTYPRIDDCOLLEGE,13/02/2008,UncontrolledCopy,©BSI~IISpecification.SectiononeBS1212:Part1:1990IISectionone.General1ScopeThisPartofBS1212specifiesmaterials,dimensions,tolerancesandperformancerequirementsforpistontypefloatoperatedvalves(copperalloybody)ofnominalsizes3/8,'/z,3/4,1,1'14,1'hand2withsixpatternsofbody,designatedI,II,Ill,IV,VandVI,intendedforusewithfloatscomplyingwithBS1968andBS2456.NOTE1.ThenominalsizescorrespondwiththepipesizeofthethreadontheinletshankasspecifiedinBS2779.Thenominalsizes3/xand1'/4areformedbymakingspecialinletsonthesizesand1'/zrespectively.Nominalsizes3/aand'/2aremadeinbodyformpatternIor0.NOTE2.Thetitlesofthepublicationsreferredtointhisstandardarelistedontheinsidebackcover.2DefinitionForthepurposesofthisPartofBS1212thefollowingdefinitionapplies.pistontypefloatoperatedvalve.Anon-equilibriumfloatoperatedvalveinwhichtheflowofwateriscontrolledbythehorizontalmovementofapiston.3DesignationfororderingPistontypefloato