RG1.057 一回路反应堆安全壳系统金属部件的设计限值和荷载复合 2007

TheU.S.NuclearRegulatoryCommission(NRC)issuesregulatoryguidestodescribeandmakeavailabletothepublicmethodsthattheNRCstaffconsidersacceptableforuseinimplementingspecificpartsoftheagency’sregulations,techniquesthatthestaffusesinevaluatingspecificproblemsorpostulatedaccidents,anddatathatthestaffneedinreviewingapplicationsforpermitsandlicenses.Regulatoryguidesarenotsubstitutesforregulations,andcompliancewiththemisnotrequired.MethodsandsolutionsthatdifferfromthosesetforthinregulatoryguideswillbedeemedacceptableiftheyprovideabasisforthefindingsrequiredfortheissuanceorcontinuanceofapermitorlicensebytheCommission.Thisguidewasissuedafterconsiderationofcommentsreceivedfromthepublic.TheNRCstaffencouragesandwelcomescommentsandsuggestionsinconnectionwithimprovementstopublishedregulatoryguides,aswellasitemsforinclusioninregulatoryguidesthatarecurrentlybeingdeveloped.TheNRCstaffwillreviseexistingguides,asappropriate,toaccommodatecommentsandtoreflectnewinformationorexperience.WrittencommentsmaybesubmittedtotheRulesandDirectivesBranch,OfficeofAdministration,U.S.NuclearRegulatoryCommission,Washington,DC20555-0001.Regulatoryguidesareissuedin10broaddivisions:1,PowerReactors;2,ResearchandTestReactors;3,FuelsandMaterialsFacilities;4,EnvironmentalandSiting;5,MaterialsandPlantProtection;6,Products;7,Transportation;8,OccupationalHealth;9,AntitrustandFinancialReview;and10,General.Requestsforsinglecopiesofdraftoractiveregulatoryguides(whichmaybereproduced)shouldbemadetotheU.S.NuclearRegulatoryCommission,Washington,DC20555,Attention:ReproductionandDistributionServicesSection,orbyfaxto(301)415-2289;[e-mail]ideandotherrecentlyissuedguidesareavailablethroughtheNRC’spublicWebsiteundertheRegulatoryGuidesdocumentcollectionoftheNRC’sElectronicReadingRoomat’sAgencywideDocumentsAccessandManagementSystem(ADAMS)at(DraftwasissuedasDG-1158,datedOctober2006)DESIGNLIMITSANDLOADINGCOMBINATIONSFORMETALPRIMARYREACTORCONTAINMENTSYSTEMCOMPONENTSA.INTRODUCTIONThisregulatoryguidedescribesanapproachthatthestaffoftheU.S.NuclearRegulatoryCommission(NRC)considersacceptableforuseinsatisfyingtherequirementsofGeneralDesignCriteria(GDC)1,2,4,and16,asspecifiedinAppendixA,“GeneralDesignCriteriaforNuclearPowerPlants,”toTitle10,Part50,oftheCodeofFederalRegulations(10CFRPart50),“DomesticLicensingofProductionandUtilizationFacilities”(Ref.1).Specifically,GDC1,“QualityStandardsandRecords,”requires,inpart,thatstructures,systems,andcomponents(SSCs)importanttosafetybedesigned,fabricated,erected,andtestedtoqualitystandardscommensuratewiththeimportanceofthesafetyfunctionstobeperformed.Toaugmentthoserequirements,GDC2,“DesignBasesforProtectionAgainstNaturalPhenomena,”requiresthatstructuresimportanttosafetybedesignedtowithstandtheeffectsofexpectednaturalphenomenawhencombinedwiththeeffectsofnormalaccidentconditionswithoutlossofcapabilitytoperformtheirsafetyfunction.Inaddition,toensurethatthecontainmentofanuclearpowerplantisdesignedtowithstandnaturalphenomena,itisnecessarytospecifythemostseverenaturalphenomenaeventthatmayoccurasafunctionofthefrequencyofoccurrence.Similarly,GDC4,“EnvironmentalandDynamicEffects,DesignBases,”requiresthatnuclearpowerplantSSCsimportanttosafetybedesignedtoaccommodatetheeffectsofandbecompatiblewithenvironmentalconditionsassociatedwithnormaloperation,maintenance,testing,andpostulatedaccidents,includingloss-of-coolantaccidents(LOCAs).Rev.1ofRG1.57,Page2Inaddition,GDC16,“ContainmentDesign,”requiresthatthereactorcontainmentanditsassociatedsystemsbeprovidedtoestablishanessentiallyleaktightbarrieragainstuncontrolledreleaseofradioactivitytotheenvironmentandtoensurethatdesignconditionsimportanttosafetyarenotexceededforaslongasrequiredforpostulatedaccidentconditions.Finally,GDC50,“ContainmentDesignBasis,”requiresthatthereactorcontainmentstructure(includingaccessopenings,penetrations,andcontainmentheatremovalsystems)bedesignedsothatthestructureanditsinternalcompartmentswillhavethecapabilitytoaccommodate,withoutexceedingthedesignleakagerateandwithsufficientmargin,thecalculatedpressureandtemperatureconditionscausedbyaLOCA.10CFR50.44providestherequirementsforcombustiblegascontrolforcurrently-licensedreactorsandforfuturewater-cooledreactorapplicantsandlicensees.ThisregulatoryguidedescribesanapproachacceptabletotheNRCstafftoconsiderthestructuralloadsinvolvedanddeterminethecontainmentresponsetodemonstratethecontainmentstructuralintegrity.Moreover,leaktightnessofthecontainmentstructuremustbetestedatregularintervalsduringthelifeoftheplant,inaccordancewiththeprovisionsof10CFRPart50,AppendixJ,“PrimaryReactorContainmentLeakageTestingforWater-CooledPowerReactors.”Inaddition,forcertainreactorsspecifiedin10CFR50.34(f),10CFR50.34(f)(3)(v)(A)and(B)requiresteelcontainmentstomeetspecificprovis