IFI-524-2002 非金属预置扭矩螺钉防松性能测试程序 公制系列

IFI-524-2002非金属预置扭矩螺钉防松性能测试程序公制系列TESTPROCEDUREFORTHEPERFORMANCEOFMETRICNONMETALLICRESISTANTELEMENTPREVAILING-TORQUESCREWSPublishedandissuedbytheIndustrialFastenersInstituteofCleveland,OHIFISTANDARD®Issued:1982Revised:July2002IFI-524feature,andnotbecauseofacompressiveloaddevelopedagainsttheunderheadbearingsurfaceofthescreworatensileloaddevelopedintheshankofthescrew.1.3.2REPTscrewsaremetallicscrewstowhichhavebeenaddedanonmetallicinsertorfusednonmetallicsubstanceintheirthreadedlength.Thedesignoftheprevailing-torquefeatureshallbeinaccordancewiththepracticeofthemanufacturer.Dependingupontheamountoffrictionpresentbecauseofsurfacefinishandlubri-cants,thedimensionalcharacteristicsofthenonmetallicelementmayvarytoachievetheperformancerequire-mentsstatedinTable1.1.3.3Forpurposesofthisstandard,"lot"meansaquantityoffastenersofonepartnumberfabricatedbythesameproductionprocessfromthesamecoilorheatnumberofmetalasprovidedbythefastenermanufacturerandsubmittedforinspectionandtest-ingatonetime.2.0PropertyClasses.2.1PropertyClasses.ThisstandardcoversonlysteelREPTscrewsproducedtomeettheme-chanicalstrengthrequirementsofoneoffourbasicpropertyclasses,8.8,9.8,10.9and12.9asspecifiedinASTMF568.ThestandardsizesofREPTscrewsforeachofthefourpropertyclassesaregiveninTable1.3.0ReferencedStandards.Allstandardsarelatestissueunlessotherwiseagreedbetweenmanufacturerandpurchaser.3.1ASMEStandards.ThesemaybeobtainedfromASME;ThreeParkAvenue;NewYork,NY10016-5990.•B1.3MScrewThreadGagingSystemsforDimensionalAcceptability–InchandMetricScrewThreads,(UN,UNR,UNJ,MandMJ)1.0Scope.1.1ThisstandardestablishesaconformancetestprocedurefortheperformanceofmetricNonmetallicResistantElementTypePrevailing-TorqueScrews(hereinaftercalledREPTscrew),innominalthreaddiametersM1.6thruM36.Theprevailing-torquevaluesgiveninthisstandardareconformancerequirementsoftestcon-ditionsdescribedintheperformancetestprocedure(5.1).Iftheconditionsoftheactualserviceapplica-tiondifferfromthoseof5.1(e.g.,internallythreadedholeinadifferentmaterial,lengthofthreadengage-ment,classofinternalthreadtolerance,speedofdriving,differentplatingorcoatingonscrewormat-ingpart),theprevailing-torquevaluesmaydiffer.SuchvaluescanonlybedeterminedthroughtestingtheREPTscrewinitsspecificapplication.Thisstandardisnotconcernedwithdimen-sionalfeaturessuchasheadstyles,orwithperfor-mancecapabilitiessuchasstrengthproperties,cor-rosionresistance,sealing,suitabilityforuseinhighorlowtemperatures,and/orconsistencyoftorque-to-tensionrelationshipsduringassembly.Suchfea-turesandpropertiesarecoveredinotherstandardsandspecificationsandmustbereferencedwhenspecifyingaREPTscrewtoassurethatalloftheserviceconditionsoftheparticularengineeringap-plicationareproperlymet.(Note:Theapplicationofsomenonmetallicelementsrequiresheatingofanisolatedareainthescrewthreadtoapproximately316ºCwhichmayhaveanadverseeffectonthemechanicalproper-tiesofsomeproducts.)1.2WhiletherequirementsofthisstandardapplytoREPTscrews,itisnottheintenttoprecludealternatetypesofscrewswhichtotallysatisfytherequirementsofthisstandard.1.3Definitions.1.3.1Aprevailing-torqueREPTscrewisanexter-nallythreadedfastenerwhichisfrictionallyresistanttorotationduetoaself-containedprevailing-torquePage1of5TESTPROCEDUREFORTHEPERFORMANCEOFMETRICNONMETALLICRESISTANTELEMENTPREVAILING-TORQUESCREWSPublishedandissuedbytheIndustrialFastenersInstituteofCleveland,OHIFISTANDARD®Issued:1982Revised:July2002IFI-524•B1.13MMetricScrewThreads–MProfile3.2ASTMStandards.ThesemaybeobtainedfromASTM;100BarrHarborDrive;WestConshohocken,PA19428-2959.•ASTMF568MCarbonandAlloySteelExter-nallyThreadedMetricFasteners4.0Requirements.4.1Finish.REPTscrewsshallbefurnishedplainorwithaprotectivecoatingasspecifiedbythepurchaser.Attheoptionofthemanufacturer,screwsmaybeprovidedwithasupplementarylubricant.4.2Threads.4.2.1ThreadTolerances.ThreadsofREPTscrewsshallbetoleranceclass6gasspecifiedinASMEB1.13M,exceptthattheportionofthethreadedlengthcontainingthenonmetallicelementneednotconform.4.2.2ThreadStart.REPTscrews,exceptthosecoveredin4.3.2,shallassembleaminimumofonefullturnbythefingersintoanymatinginternallythreadedcomponentthathasthreadsacceptabletoGagingSystem21ofASMEB1.3M.(1)Clamploadsequal75percentoftheproofloadsspecifiedforthepropertyclassinASTMF568.Page2of5swercStnemelEtnatsiseRcillatemnoNrofseuqroT-gniliaverP1elbaTwercSmoNdnaeziShctiPdaerhT)1(daoLpmalCNk-gniliaverPeuqroTtsriFlavomeR-gniliaverPeuqroThtfiFlavomeR-gniliaverPeuqroTwercSfossalCytreporPxaMniMniM8.88.99.019.21m•Nm•Nm•N53.0×6.1M4.0×2M54.0×5.2M———6.00.16.1———9.05.15.201.002.004.010.020.050.0400.010.030.05.0×3M6.0×5.3M7.0×4M———4.23.33.4———7.39.44.606.009.02.141.022.062.060.011.061.08.0×5M1×6M52.1×8M5.1×01M————9.68.981828.3.20.3014163.054.009.08.132.003.085.01.157.1×21M2×41M2×61M5.2×02M———011146567—1120304066.26.30.50.85.13.24.35.53×42M5.3×03M4×63M061052073———022053015062014095090210513191825.83181TESTPROCEDUREFORTHEPERFORMANCEOFMETRICNONMETALLICRESISTANTELEMENTPREVAILING-TORQUESCREWSPublishedandissuedbytheIndustrialFastenersInstituteofCleveland,OHIFISTANDARD®Issued:1982Revised:July2002IFI-5244.3Performance.4.3.1Theprevailing-torqueofREPTscrewsoccur-ringduringanyinstallationorremovalshallnotexceedthemaximumprevailing-torquespecifiedinTable1whentestedasspecifiedin5.1.Inaddition,thehighestprevailing-torquesdevelopedbyREPTscrewsdur-ingfirstandfifthremovalshallnotbelessthantheminimumfirstandfifthremovaltorques,respectively,specifiedinTable1whentestedinaccordancewith5.1.Inaddition,thelowestprevailing-torquedevel-opedbyREPTscrewsduringthefifthremovalshallnotbezero,whentestedinaccordancewith5.1.4.3.2REPTscrewswhicharetooshortorwhichhavethreadlengthstooshorttopermittestinginaccordancewith5.1shallhavetheirprevailing-torquerequirementsandtestprocedureestablishedbyagree-mentbetweenthepurchaserandmanufacturer.4.4WhenREPTscrewsarealteredinanymannerbyanysourcefollowingshipmentbythemanuacturertoapurchaser,thescrewmanufacturershallnotbeheldresponsibleforfailuresofthescrewstomeetdimensionalorperformancerequirementstraceabletothealteration.5.0PerformanceTest.5.1TestProcedure.ThesampleREPTscrewshallbeassembledwithatestwasher(5.1.6)andatestnut(5.1.3)inaloadmeasuringdevice(5.1.1)withthetestwasherlocatedadjacenttothecompo-nenttobeturned.Duringthecompleteperformanceofthetest,eithertheREPTscreworthetestnutshallbeturned.WhentheREPTscrewisturned,therestrainingmechanismshallbesuchthatitimpartsnoradialdistortiontothetestnut.TheREPTscrewortestnutshallbeadvanceduntilitsbearingsurfaceisseatedagainstthetestwasher.Thetotalthicknessofspacermaterialinthetestassemblyshallbeselectedsothatatseating,themid-lengthofthenonmetallicelementofthescrewshallcoincideascloselyaspracticalwiththemid-thicknessofthetestnut,andaminimumlengthofREPTscrewequivalenttotwothreadpitchesshallprojectthroughthetopofthetestnut.Duringthisfirstinstallation,thehighestprevailing-torque(firstontorque)occurringwhiletheREPTscrewortestnutisinmotionandpriortodevelopmentofanyaxialloadshallbemeasuredandrecorded.TighteningshallbecontinueduntilanaxialtensileclamploadequaltotheloadasspecifiedinTable1fortheapplicablescrewsizeandpropertyclassisdeveloped.TheaxialtensileclamploadintheREPTscrewshallbereducedtozerobybackingtheturnedmemberoffuntilthetestwasherisfreetomovebythefingers.Followingapause(itisgenerallynecessarytochangethewrenchtooneofalowertorquecapac-ity),removalshallbecontinuedandthehighesttorque(firstremovaltorque)occurringwhiletheREPTscrewortestnutisbeingbackedoffthroughoutthenext360degofrotationshallbemeasuredandre-corded.TheREPTscrewandtestnutshallbedisassembledandthenreassembledanddisas-sembledtwomoretimes.OneachreassemblytheREPTscrewshallbeassembledwiththetestnutuntiltheturnedelementisseatedagainstthetestwasher,butnotensileloadshallbeinducedintheREPTscrew.Duringthethirdremoval,thehighesttorque(thirdremovaltorque)occurringwhiletheREPTscrewortestnutisbeingbackedoffthrough-outthefirst360degofrotationshallbemeasuredandrecorded.Atnotimeduringthis360degofrotationshallthetorquebezero.Atnotimeduringthetwoadditionalinstalla-tionsandremovalsshouldtheprevailing-torqueex-ceedthemaximumprevailing-torqueasspecifiedinTable1.(Note:Theintentofthisprecedingrequire-mentistodemonstratethatgallingbetweenthesampleREPTscrewandtestnuthasnotoc-curred.WithcertaindesignsofREPTscrewstheremaybeanincreaseintheprevailing-torquedur-ingthethreeassemblycyclesandinrarein-stancesthespecifiedmaximumprevailing-torquemaybeexceeded.Insuchinstancesthemanufac-turer,whenrequested,shallgiveevidencethatgallingwasnotacontributingfactor.)Page3of5TESTPROCEDUREFORTHEPERFORMANCEOFMETRICNONMETALLICRESISTANTELEMENTPREVAILING-TORQUESCREWSPublishedandissuedbytheIndustrialFastenersInstituteofCleveland,OHIFISTANDARD®Issued:1982Revised:July2002IFI-524Testblocksmustmeetthesamethreadtoleranceastestnuts.5.1.5Usage.Anewtestnutshallbeusedfortestingeachscrew.Priortotheusageofatestnut,itsthreadsshallbegagedandshallbeacceptabletotherequirementsofGagingSystem21ofASMEB1.3M.AlternatetestingwithtestblockshallrequiregagingpriortousageandgagingaftereachscrewtesttotherequirementsofGagingSystem21ofASMEB1.3M.5.1.6TestWasher.Washersshallbesteelwithdimensions,hardnessandfinishatoptionoftestingagency.6.0Inspection.6.1InspectionProcedure.REPTscrewsshallbeinspectedtodetermineconformancewiththerequirementsofthisstandard.Unlessotherwisespecified,fromeachlotofREPTscrewsthefollowingnumberoftestsshallbeconductedtodeterminetheacceptabilitytoeachoftherequirements:Alternateinspectionproceduresmaybespecifiedbythepurchaseronthepurchaseorderorengineeringdrawing.Sufficienttimeshallelapsebetweentorquingcyclestopreventoverheatingofthetestassembly.Speedofdrivingshallnotexceed30RPM.5.1.1TensileLoadMeasuringDevice.ThetensileloadmeasuringdeviceshallbeaninstrumentcapableofmeasuringtheactualtensioninducedintheREPTscrewasitisbeingtightened.Thedeviceshallbeaccuratewithinplusorminus5percentofthetensileclamploadtobeinduced.DiameteroftheREPTscrewclearanceholeinthebackingplateshallbetheREPTscrewnominalsizeplus0.4mmforscrewsizesM5andsmaller,plus0.8mmforsizesM6toM24incl.,andplus1.6mmforsizesM30andM36.5.1.2Torquewrenchesshallbeaccuratewithinplusorminus2percentofthemaximumofthespecifiedtorquerangeofthewrench.5.1.3TestNut.Thetestnutshallconformtodi-mensionsgiveninTable2.Alternately,atestblockmaybeusedaslongasitsthicknessandcountersinkcomplywithTable2.Nutsortestblocksshallbemadeofcarbonsteel,andshallhaveproofloadstrengthsequaltoorgreaterthantheminimumspecifiedultimatestrengthofthescrewbeingtested.Testblocksshallmeetthesamemechanicalrequire-mentsastestnuts.5.1.4ThreadTolerance.AlltestnutsshallbeClass6HwhentestingscrewswithClass6gorClass4g6g.Testnutsshallbefreeofrustanddirtandshallhaveaplainfinishwithlightoilcoating.Thescrewshallbeassembledintothecountersunksideofthenut.Alternatetestingusingagageblockshallbeusedonlybyagreementofpurchaserandsupplier.Page4of5eziStoL)seceip(stseTfo.oN05ot005ot15000,53ot105000,53revo2358TESTPROCEDUREFORTHEPERFORMANCEOFMETRICNONMETALLICRESISTANTELEMENTPREVAILING-TORQUESCREWSPublishedandissuedbytheIndustrialFastenersInstituteofCleveland,OHIFISTANDARD®Issued:1982Revised:July2002IFI-524Page5of5*NutsizesM1.6thruM2.5arebasedonASMEB18.2.4.1MStyle1.(1)NutsizesM3.0thruM36arebasedonASMEB18.2.4.2MStyle2.stuNtseTfosnoisnemiD2elbaTlanimoNeziSssorcAhtdiWstalFssorcAhtdiWsrenroCtuNssenkcihT°021–°09aiDknisretnuoCxaMniMxaMniMxaMniMxaMniM6.1M02.320.307.314.303.150.148.106.10.2M00.428.326.423.406.153.103.200.25.2M00.528.477.554.500.257.1578.205.20.3M05.523.553.610.609.256.254.300.35.3M00.628.539.685.603.300.3520.405.30.4M00.787.680.866.708.305.306.400.40.5M00.887.742.997.801.508.457.500.50.6M00.0187.955.1150.1107.504.557.600.60.8M00.3137.2110.5183.4105.741.757.800.80.01M00.6137.5184.8177.7103.949.808.0100.010.21M00.8137.7187.0230.0200.2175.1169.2100.210.41M00.1276.0252.4253.3201.4104.3121.5100.410.61M00.4276.3217.7257.6204.6107.5182.7100.610.02M00.0361.9246.4359.2303.0200.9106.1200.020.42M00.6300.5375.1455.9309.3206.2229.5200.420.03M00.6400.5421.3558.0506.8203.7204.2300.030.63M00.5508.3515.3697.0607.4301.3388.8300.63