【astm標(biāo)準(zhǔn)】e 2658 - 15

1、Designation:E2658?15StardPracticesfVerificationofSpeedfMaterialTestingMachines1ThisstardisissuedunderthefixeddesignationE2658thenumberimmediatelyfollowingthedesignationindicatestheyearofiginaladoptioninthecaseofrevisiont

2、heyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.1.Scope1.1Thesepracticescoverproceduresrequirementsfthecalibrationverificati

3、onoftestingmachinespeedbymeansofstardcalibrationdevices.Thispracticeisnotintendedtobecompletepurchasespecificationsftestingmachines.1.2Thesepracticesapplytotheverificationofthespeedapplicationmeasuringsystemsassociatedwi

4、ththetestingmachinesuchasascaledialmarkedunmarkedrecdertdigitaldisplaysettingetc.Inallcasesthebuyerownerusermustdesignatethespeedmeasuringsystem(s)tobeverified.1.3Thesepracticesgiveguidancerecommendationsexamplesspecific

5、toelectromechanicaltestingmachines.Thepracticemayalsobeusedtoverifyactuatspeedfhydraulictestingmachines.1.4Thisstardcannotbeusedtoverifycyclecountingfrequencyrelatedtocyclicfatiguetestingapplications.1.5Sinceconversionfa

6、ctsarenotrequiredinthispracticeeitherSIunits(mmmin)English[inmin]canbeusedasthestard.1.6Speedmeasurementvaluessettingsondisplaysprintoutsoftestingmachinedatasystemsbetheyinstantaneousdelayedstedretransmittedwhicharewithi

7、ntheClassificationcriterialistedinTable1complywithPracticesE2658.1.7Thisstarddoesnotpurpttoaddressallofthesafetyconcernsifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafetyhealt

8、hpracticesdeterminetheapplicabilityofregulatylimitationspritouse.2.ReferencedDocuments2.1ASTMStards:2E2309PracticesfVerificationofDisplacementMeasuringSystemsDevicesUsedinMaterialTestingMachines3.Terminology3.1Definition

9、s:3.1.1percenterrn—inthecaseofaspeedmeasuringsystemtheratioexpressedasapercentoftheerrtothereferencevalueoftheappliedspeed.3.1.1.1Discussion—Thespeedasmeasuredbythetestingmachinethespeedascomputedfromthereadingsofthecali

10、brationdevicesshallberecdedateachverifiedspeed.Thepercenterrshallbecalculatedfromthisdataasfollows:PercentErr5@~TMsp2Refsp!Refsp#3100(1)where:TMsp=speedmeasuredbythemachinebeingverifiedmmmin[inmin]Refsp=referencevalueoft

11、hemeasuredspeedmmmin[inmin]asdeterminedbythecalibrationdevice.Notalltestingmachineshaveavailableindicatedspeedvalues.Insuchcasestheverificationofthetestingmachine’sspeedsettingisapplicable.Thepercenterrfthetestingmachine

12、speedsettingsshallbecalculatedasfollows:PercentErr5@~TMsps2Refsp!Refsp#3100(2)where:TMsps=testingmachinespeedsettingmmmin(inmin)Refsp=referencevalueofthemeasuredspeedmmmin(inmin)asdeterminedbythecalibrationdevice.3.1.2ra

13、mptospeedconditionn—duringaspeedverificationrunitisthetimechangeindisplacementrequiredtoachieveaconstantspeedcondition.1ThesepracticesareunderthejurisdictionofASTMCommitteeE28onMechanicalTestingisthedirectresponsibilityo

14、fSubcommitteeE28.01onCalibrationofMechanicalTestingMachinesApparatus.CurrenteditionapprovedMay12015.PublishedAugust2015.iginallyapprovedin2011.Lastpreviouseditionapprovedin2011asE2658–11.DOI:10.1520E2658–15.2FreferencedA

15、STMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.Copyright?ASTMInternational100BarrHarbDrivePOBoxC700WestConsho

16、hockenPA194282959.UnitedStates16.3Theverificationshallconsistofatleasttwoverificationrunsofspeedderiveddataperedtestingmachinespeedsetting.6.3.1Iftheinitialverificationrunproducesanypercenterrvaluesoutsideapplicablespeci

17、ficationsthe“asfound”datamaybereptedmaybeusedinaccdancewithapplicablequalitycontrolprograms.6.3.2Adjustmentsmaybemadetoimprovetheaccuracyofthesystem.Theyshallbefollowedbyoneadditionalverificationrunissuanceofanewverifica

18、tionrept.Typicallymakingadjustmentstoimprovetestingmachinespeedwillinfluenceallspeedsettings.Ifanadjustmentismadealltestedspeedsmustbereverifiedunlessitcanbedemonstratedthattheadjustmentdidnotaffectotherspeedsettings.6.3

19、.3Qualitycontrolprogramsmayrequireevidenceofrepeatabilityreproducibilityreversibility.Insuchcasesitisrecommendedthataminimumofonespeedbeverifiedfrepeatabilityreproducibilityreversibility.6.4Thetestingmachineisverifiedwit

20、hthecrossheadconfiguredtofreerunwithnospecimeninstalled.NOTE2—Testingmachinecomplianceunderloadingconditionsmayintroducesmallerrsinthedisplacementmeasurementdataduringactualmaterialstesting.Thiserrisconsideredinsignifica

21、ntrelativetothisverification.Therearealsotestingmachineswherethecrossheadspeedslowswhenfceisapplied.Insuchcaseswhereitisnecessarytoverifyspeedofthetestingmachineunderloadedconditionshigheraccuracydisplacementcalibrationd

22、evicessuchaslaserinterferometermeasuringsystemsextensometertypedisplacementreferencestardsmustbeusedduetotheverysmalldisplacementsbeingverified.7.MethodsofVerification7.1StartStopMethod:7.1.1Thismethodrequiresthatasetofs

23、tartingstoppingdisplacementtimereadingsberecdedfromthedisplacementtimecalibrationdevices.7.1.2Indertoobtaindatawithinexpectedtolerancesanassessmentoftheramptospeedconditionmaybenecessarysothetestruncanbestartedafterthecr

24、ossheadhasreachedaconstantspeedcondition.7.1.3Itisbesttohavetestingmachinesoftwarethatcaneasilyacquirereptdisplacementtimedataduringtheverificationrunfeachedspeed.7.1.4Thecomparisonofthereferencestartstopvaluesthedatarep

25、tedbythetestingsystemprovidesthebasisfverificationofspeedusingthismethod.7.2ContinuousAcquisitionMethod:7.2.1Thisisthepreferredmethodofverifyingtestingmachinespeed.7.2.2Thismethodrequiresautomatedcomputersoftwaretoacquir

26、edatafromthedisplacementcalibrationdevice.7.2.3Thismethodcanbeusedtoadequatelyassesstheramptospeedconditionfeachspeedsettingverified.7.2.4Thismethodcanshowvariabilityinthetestingmachinespeedthroughouttheverificationrun.8

27、.ionofVerificationSpeedValues8.1Manytestingmachineshaveaionofpresetcrossheadspeedstypicallyrangingfrom.025mmminto10000mmminute(.001inminto400inminute).Itisdifficultverytimeconsumingtoverifyeveryablesettingavailablewithte

28、stingmachines.Additionallyitisoftenimpossibletoadequatelyverifythefastestspeedionsbecausedisplacementcalibrationdevicesaretypicallynotlongenoughtoaccommodatethedisplacementnecessary.Fthesereasonsataminimumspeedsmostcommo

29、nlyusedshouldbeedfverification.Aminimumoftworunsofverificationdatafeachspeedisrequired.8.1.1Insomecasesatestingmachinemightonlybeusedatonespeedwithoneclutched.Insuchacaseonlyonespeedwithtworunsofdataareallthatisrequiredt

30、omeetthisstard.8.2Manytestingmachineshavemultipleclutchions.Ifthetestingmachineisusedwithmultipleclutchsettingsspeedsfeachclutchsettingshallbeverifiedeveniftheedspeedisthesameasaedspeedverifiedwithadifferentclutchsetting

31、.8.3Iningspeedstobeverifiedconsiderationofthetotaldisplacementtimemustbeconsidered.Thetotaldisplacementmustbegreatenoughtoallowfthedisplacementcalibrationdevice’smeasurementuncertainty.Ifthecalibrationdevicesareautomated

32、timeisnotascriticaltotheoverallmeasurementuncertainty.ButifamanualStartStopmethodisemployedthedurationoftheverificationrunmustbelongenoughtominimizeerrduetohumanaction.ThemanualStartStopmethodalsorequiresthatthetotaldisp

33、lacementdurationoftheverificationrunbelongenoughtostartbeyondtheramptospeedcondition.SeeAppendixX1.8.4Itisnotnmaltoexperienceadifferenceinthespeedindicationofthetestingmachinewhenthecrossheadmovesintheoppositedirection.H

34、owevergravitymaycontributetoadifferenceintheramptospeedconditionwhenthecrossheadisoperatedinthedescendingmode.Thetestingmachineshouldbeverifiedinthemodeofoperationnmallyusedduringtesting.9.PreliminaryProcedure9.1Alignmen

35、t:9.1.1Whenattachingthedisplacementcalibrationdeviceitisimptanttominimizeanymisalignment.Significanterrscanbeinducedduetomisalignment.Gaugeblocksasquaremaybeusedtoensurethatthedisplacementcalibrationdeviceoperatesperpend

36、iculartothecrossheadinelectromechanicaltestingmachinesinlineparalleltotheactuatinhydraulictestingmachines.9.2TemperatureConsiderations:9.2.1Turnonpowerallowthecomponentstowarmupfaperiodoftimerecommendedbythemanufacturer.

37、Intheabsenceofanyrecommendationsallowatleast15minutesfthecomponentstostabilize.9.2.2Positionatemperaturemeasuringdeviceincloseproximitytothemachinebeingverified.Allowthespeedmeasuringdeviceallrelevantpartsoftheverificati