1、BRITISH STANDARD Devices to prevent pollution by backflow of potable water Controllable backflow preventer with reduced pressure zone Family B Type A ICS 13.060.20; 91.140.60 BS EN 12729:2002 Incorporating corrigendum April 2009BS EN 12729:2002 National foreword This British Standard is the UK imple
2、mentation of EN 12729:2002. The UK participation in its preparation was entrusted by Technical Committee B/504, Water upply, to Subcommittee B/504/4, Backflow revention. A list of organizations represented on this committe can be obtained on request to its secretary. This publication does not purpor
3、t to include all necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standard Policy and Strategy Committee on 30 Januar
4、y 2003 BSI 2009 ISBN 978 0 580 65889 1Date Comments Correction to the committee details in the ational foreword s p sub e the Amendments/corrigenda issued since publicationn 3 April 2009 0EUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN12729 November2002 ICS13.060.20;91.140.60 Englishversion Device
5、stopreventpollutionbybackflowofpotablewater Controllablebackflowpreventerwithreducedpressurezone FamilyBTypeA Dispositifsdeprotectioncontrelapollutionparretourde leaupotableDisconnecteurzonedepressionrduite contrlableFamilleBTypeA SicherungseinrichtungenzumSchutzdesTrinkwassers gegenVerschmutzungdur
6、chRckflieenSystemtrenner mitkontrollierbarerdruckreduzierterZoneFamilieBTyp A ThisEuropeanStandardwasapprovedbyCENon7September2002. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteratio
7、n.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoits
8、ownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandUnitedKingdo
9、m. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2002CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN12729:2002EEN12729:2002(E) 2 Contents page Foreword3 In
10、troduction .4 1 Scope 5 2 Normativereferences 5 3 Termsanddefinitions. .6 4 Denomination .7 5 Designation.7 6 Symbolization.7 7 Physicochemicalcharacteristics 8 7.1 Materials8 7.2 Natureofthematerials . .8 8 Design .9 8.1 General9 8.2 Reliefvalve .9 9 Characteristicsandtests . .10 9.1 General10 9.2
11、Generaltolerances .10 9.3 Expressionoftheresults. .10 9.4 Dimensionalcharacteristics . 10 9.5 Mechanicalcharacteristics .11 9.6 Tightnesscharacteristics. .15 9.7 Hydrauliccharacteristics . .18 10 Orderoftesting . .23 11 Markingandtechnicaldocuments .24 11.1 Marking .24 11.2 Technicaldocuments 24 12
12、Presentationatdelivery . .25 AnnexA (informative) Examplesofpresentationoftestresults.26 Bibliography 32 BS EN12729:2002EN12729:2002(E) 3 Foreword Thisdocument(EN12729:2002)hasbeenpreparedbyTechnicalCommitteeCEN/TC164“Watersupply“,the secretariatofwhichisheldbyAFNOR. ThisEuropeanStandardshallbegiven
13、thestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyMay2003,andconflictingnationalstandardsshallbewithdrawnatthelatestby May2003. TheannexAisinformative. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesa
14、reboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Spain, Sweden,SwitzerlandandtheUnitedKingdom. BS EN12729:2002EN12729:2002(E) 4 Introduction Inrespectofpotentialadverseeffect
15、sonthequalityofwaterintendedforhumanconsumption,causedbythe productcoveredbythisstandard: a) thisstandardprovidesnoinformationastowhethertheproductmaybeusedwithoutrestrictioninanyofthe MemberStatesoftheEUorEFTA; b) itshouldbenotedthat,whileawaitingtheadoptionofverifiableEuropeancriteria,existingnati
16、onalregulations concerningtheuseand/orthecharacteristicsofthisproductremaininforce. BS EN12729:2002EN12729:2002(E) 5 1Scope ThisEuropeanStandardspecifiesthefieldofapplication,thedimensional,thephysicochemical,thedesign,the hydraulic,themechanical,andtheacousticcharacteristicsofcontrollablebackflowpr
17、eventerwithreduced pressurezoneFamilyBTypeA. ThisstandardcoverscontrollablebackflowpreventersofFamilyBTypeA,withreducedpressurezones,intended topreventbackflowbybacksiphoningorbackpressureofwaterintothepotablewaterdistributionsystemwhenever thepressureofthelatterislowerthanthesystemlocateddownstream
18、. ItisapplicabletocontrollablebackflowpreventersindenominationsDN8uptoDN250. ItcoverscontrollablebackflowpreventersofPN10thatarecapableofworkingwithoutmodificationoradjustment: atanypressureupto1MPa(10bar); withanypressurevariationupto1MPa(10bar); inpermanentdutyatalimitedtemperatureof65Cand90Cfor1h
19、maximum. Itspecifiesalsothetestmethodsandrequirementsforverifyingtheircharacteristics,themarkingandthe presentationatdelivery. 2 Normativereferences ThisEuropeanStandardincorporatesbydatedorundatedreference,provisionsfromotherpublications.These normativereferencesarecitedattheappropriateplacesinthet
20、ext,andthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplytothisEuropean Standardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthelatesteditionofthe publicationreferredtoapplies(includingamendments). EN8061:2000, Sp
21、ecificationsforinstallationsinsidebuildingsconveyingwaterforhumanconsumptionPart1: General. EN10921, FlangesandtheirjointsCircularflangesforpipes,valves,fittingsandaccessories,PNdesignated Part1:Steelflanges. EN10922, FlangesandtheirjointsCircularflangesforpipes,valves,fittingsandaccessories,PNdesig
22、nated Part2:Castironflanges. EN1717:2000,Protectionagainstpollutionofpotablewaterinwaterinstallationsandgeneralrequirementsof devicestopreventpollutionbybackflow. ENISO38221, AcousticsLaboratorytestsonnoiseemissionfromappliancesandequipmentusedinwater supplyinstallationsPart1:Methodofmeasurement(ISO
23、38221:1999). ENISO38223:1997, AcousticsLaboratorytestsonnoiseemissionfromappliancesandequipmentusedinwater supplyinstallationsPart3:Mountingandoperatingconditionsforinlinevalvesandappliances (ISO38223:1997). ENISO6509, CorrosionofmetalsandalloysDeterminationofdezincificationresistanceofbrass(ISO 650
24、9:1981). prEN13959, AntipollutioncheckvalvesDN6toDN250inclusiveFamilyETypeA,B,CandD. ISO71, PipethreadswherepressuretightjointsaremadeonthethreadsPart1:Dimensions,tolerancesand designation. BS EN12729:2002EN12729:2002(E) 6 ISO2281, PipethreadswherepressuretightjointsarenotmadeonthethreadsPart1:Dimen
25、sions,tolerances anddesignation. ISO9227, CorrosiontestsinartificialatmosphereSaltspraytests. 3 Termsanddefinitions ForthepurposesofthisEuropeanStandard,thetermsanddefinitionsofEN1717andEN8061togetherwiththe followingapply. 3.1 controllablebackflowpreventerwithreducedpressurezoneFamilyBTypeA thespec
26、ificcharacteristicsofthisdevicecalled“BA”,(seeFigure1)areasfollows: 3pressurezonessuchthatupstream p 1 intermediate p i downstream p 2 (staticnoflowandunderwaterflow conditions); p 1 p i 14kPa(140mbar); connectionfromtheintermediatepressurezone( p i )totheatmospherewhen p 1 p i 14kPa(140mbar); disco
27、nnectionbyventingtheintermediatepressurezone( p i )totheatmospherewhen p 1 shallbeupto14kPa (140mbar); aminimumsetdischargeflow(backflowrate); devicesthatallowverificationineveryzoneofthedisconnectionandthesealingoftheprotectiondevices (obturators,dischargevalves). Key 1 Upstreamzone p 1 2 Intermedi
28、atezone p i 3 Downstreamzone p 2 Figure1Designprinciple ForthepurposesofthisstandardcontrollablebackflowpreventerBAishereafterreferredtoasdevice. BS EN12729:2002EN12729:2002(E) 7 4Denomination ThedenominationofthedeviceisgiveninTable1: Table1DNversusthreadsandflanges D e n o m i n a t i o n D N 8 1
29、01 52 02 53 24 0 Threads (designationinaccordance withISO71) 1/4 3/8 1/2 3/4 1 1 1/4 1 1/2 Flanges(DN) 40 DenominationDN 50 65 80 100 125 150 200 250 Threads (designationinaccordance withISO71) 2 Flanges(DN) 50 65 80 100 125 150 200 250 NOTE Forspecificationsofthreadsandflangessee9.4. 5Designation A
30、controllablebackflowpreventerwithreducedpressurezoneFamilyBTypeAisdesignatedby: its name; itsfamilyanditstype; itsdenomination(seeTable1); itsconnectiontype; thematerialofitsbody; itssurfacefinish(possiblecoating); theacousticgroup(forDN 32); thereferencetothepresentstandard. Examplesforadesignation
31、: ControllablebackflowpreventerwithreducedpressurezoneFamilyBTypeA,DN32,G1“1 /4xG1“1/4, bronze,I,EN12729. ControllablebackflowpreventerwithreducedpressurezoneFamilyBTypeA,DN100,flanged,castiron,epoxy coated,EN12729. 6Symbolization Thegraphicrepresentationofthe controllablebackflowpreventerwithreduce
32、dpressure zoneFamilyBTypeAis asfollows(seeFigure2): BS EN12729:2002EN12729:2002(E) 8 Figure2Graphicsymbol 7 Physicochemicalcharacteristics 7.1Materials Thematerialsandthecoatingsused,liabletocomenormallyoraccidentallyincontactwithpotablewater,shall satisfytheEUregulationsconcerningwaterquality. Andt
33、herefore,they: shallbecorrosionresistant; shallbepronetotheleastscalingpossible; shallbeinconformitywiththeEuropeanStandardsandregulations; shallbecompatibleamongthemselvesand: withthewaterdistribute; withthefluidsormatterliabletocomeintocontactwiththem; withtheproductsnormallyusedfordisinfectionope
34、rationsofthenetworks:potassiumpermanganateand sodiumhypochlorite. 7.2 Natureofthematerials a) Thechoiceofmaterialsislefttothediscretionofthemanufacturer. Copperzincalloyscontainingmorethan10%zincaresubjecttodezincificationwhensubmittedtowater capableofdezincification.Inthecountrieswheretheuseofprodu
35、ctsmadeofdezincificationresistant materialsisrequired,theproductshavetoguaranteeadezincificationdepthlessthan200minanydirection, theyhavetobetestedinaccordancewithENISO6509andhavetobemarkedincompliancewiththe indicationsinclause11; NOTE Thisstandarddoesnotcovernonmetallicbodies. b) neitherthemateria
36、lsnorthecoatingsusedshall,bynormaloraccidentalcontactwithdrinkingwater,cause anyriskofaffectingormodifyingthewateruptoatemperatureof90C.Thesuitabilityofthewaterforhuman consumptionisdefinedbynationalregulations; c) themanufacturershallstateinhistechnicalandsalesliteraturethenatureofthematerialsandth
37、ecoatings selected; d) thematerials,andinparticularcopperalloys,forwhichrecommendationsorinternationalstandardexistsshall complywiththerelevantrecommendationsorinternationalstandards. BS EN12729:2002EN12729:2002(E) 9 8Design 8.1General a) Theinternalcomponentsofthedeviceshallbeaccessibleforinspectio
38、n,repairorreplacement;these operationsshallbepossibleonthedeviceinstalled.TodevicesDN 50. Inalltheinstallationpositionsindicatedbythemanufacturer,anywaterretentionshallnotbepossiblewithinthe intermediatezone. Thecrosssectionsofthepassageorificesandofthepilottubeforoperationthereliefdeviceshallbeequa
39、ltoor greaterthan45mm 2 withDN 15,or12,5mm 2 withDN 15,nodimensionforthecalculationofthecrosssection shallbelessthan4mm.Theoutsidepilottubeshallbemadesoasnottobesubjectofanypermanentdeformation orruptureunderoutsidestresses. Anairbreaktodrainshallexistbetweenanywastedrainandanymeansofcollectingthedi
40、schargedwater(floor, tundish,curb,sink,.). BS EN12729:2002EN12729:2002(E) 10 Thedevicewithanairbreaktodrainfittedshallevacuatethefullreliefflowrateasdefinedin9.7.7withoutspilling totheoutside. TheairbreaktodrainshallmeetthedimensionalrequirementsasspecifiedinEN1717. Thisairbreaktodrainshallbe: eithe
41、rdirectlyincorporatedintothedevice; orfactoryfitted; orsuppliedwiththedevice. Inthelattercase,therelieforificeofthedeviceshallpermit,neitherthefittingofastandardizedthreadedpipe,nor theconnectionofastandardizedpipeorshape,beitbyglue,weldingorinterlocking. 9 Characteristicsandtests 9.1General Perform
42、ancetestsshallbecarriedoutonthedeviceasinstalledinaccordancewiththemanufacturerstechnical documents,subjecttodimension hbeingcompliedwith. Ifnotspecifiedalltestsshallbeperformedwithwateratanambienttemperature. 9.2General tolerances 9.2.1 Accuracyofmeasurements Intheabsenceofanyparticularspecifications: flowrateandpressure: 2%ofthevaluespecified; temperature: coldwater 5Cofthevaluespecified; hotwater 2Cofthevaluespecified; time 0 10% + ofthevaluespecified. 9.2.2 Accuracyofmeasuringinstruments Allthemeasuringinstrumentsshallhaveanerrorlimitof 2%ofthemeasuredvalue. 9.3 Expressionoftheresults The
