RG1.130 一级板壳式部件支撑的服务寿命和复合载荷 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-1169,datedOctober2006)SERVICELIMITSANDLOADINGCOMBINATIONSFORCLASS1PLATE-AND-SHELL-TYPESUPPORTSA.INTRODUCTIONGeneralDesignCriterion2,“DesignBasesforProtectionAgainstNaturalPhenomena,”ofAppendixA,“GeneralDesignCriteriaforNuclearPowerPlants,”toTitle10,Part50,“DomesticLicensingofProductionandUtilizationFacilities,”oftheCodeofFederalRegulations(10CFRPart50)(Ref.1)requiresthatthedesignbasesforstructures,systems,andcomponentsimportanttosafetyreflectappropriatecombinationsoftheeffectsofnormalandaccidentconditionswiththeeffectsofnaturalphenomenasuchasearthquakes.Thefailureofmembersdesignedtosupportsafety-relatedcomponentsandpipingcouldjeopardizetheabilityofthesupportedcomponentorpipingtoperformitssafetyfunction.Thisguidedelineatesacceptablelevelsofservicelimitsandappropriatecombinationsofloadingsassociatedwithnormaloperation,postulatedaccidents,andspecifiedseismiceventsforthedesignofClass1plate-and-shell-typecomponentandpipingsupports,asdefinedinSubsectionNFofSectionIIIoftheAmericanSocietyofMechanicalEngineers(ASME)BoilerandPressureVesselCode(Ref.2).Thisguideappliestolight-water-cooledreactors.Thisregulatoryguidecontainsinformationcollectionsthatarecoveredbytherequirementsof10CFRPart50andthattheOfficeofManagementandBudget(OMB)approvedunderOMBcontrolnumber3150-0011.TheNRCmayneitherconductnorsponsor,andapersonisnotrequiredtorespondto,aninformationrequestorrequirementunlessthedocumentdisplaysavalidOMBcontrolnumber.RegulatoryGuide1.84,“Design,Fabrication,andMaterialsCodeCaseAcceptability,ASMESectionIII”(Ref.3)1providesguidancefortheacceptabilityofASMESectionIIICodeCasesandtheirrevisions,includingCodeCasesN-71andN-249.CodeCasesidentifiedas“ConditionallyAcceptableSectionIIICodeCases”areacceptable,providedthattheyareusedwiththeidentifiedlimitationsormodifications.Rev.2ofRG1.130,Page2B.DISCUSSIONBackgroundLoad-bearingmembersclassifiedascomponentandpipingsupportsareessentialtothesafetyofnuclearpowerplantsbecausetheyholdcomponentsandpipinginplaceduringloadingsassociatedwithnormalandupsetplantconditionsunderthestressofspecifiedseismicevents,therebypermittingsystemcomponentsandpipingtofunctionproperly.Load-bearingmembersalsopreventexcessivemovementofcomponentsandpipingduringtheloadingsassociatedwithemergencyandfaultedplantconditionscombinedwithaspecifiedseismiceventorothernaturalphenomena,therebyhelpingtomitigatesystemdamage.Componentandpipingsupportsaredeformation-sensitivebecauselargedeformationscansignificantlychangethestressdistributioninthesupportsystemanditssupportedcomponentsandpiping.Toprovideaconsistentlevelofsafety,theASMECodeclassificationforcomponentandpipingsupportsshould,asaminimum,bethesameasthatofthesupportedcomponentsandpiping.Thisguidedelineateslevelsofservicelimitsandloadingcombinations,aswellassupplementarycriteria,forClass1plate-and-shell-typecomponentandpipingsupports,asdefinedbyNF-1212ofSectionIIIoftheASMECode.Thisguidedoesn