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PerformanceevaluationmethodforthecaliperScaleShiftErrorSMPE[JISB7507:2016]Asaresultoftherevisionin2016toJISB7507:2016,indicationerrorsofcallipersspeciedbyJISB7507(theJapaneseIndustrialStandardofcallipers)havebeenchangedfrom“instrumentalerrors”speciedbyJISB7507:1993orearlierto“Maximumpermissibleerrors(MPEs)ofindication”.Theacceptancecriterionadoptedfor“instrumentalerrors”inJISB7507:1993orearlierregardsthespecicationrange(precisionspecications)tobethesameastheacceptancerangeanddoesnottakeintoaccountmeasurementuncertaintyinpass/failjudgement.(Fig.1)For“Maximumpermissibleerrors(MPEs)ofindication”adoptedbyJISB7507:2016,thebasicprincipleofpass/failjudgementthattakesintoaccountuncertaintyspeciedbytheISOstandard(ISO14253-1)isused.Thevericationofconformityandnonconformitytothespecicationsisclearlystipulatedtousetheinternationallyrecognizedacceptancecriteria(simpleacceptance)whenthespecicationrangeequalstheacceptancerange,anditisacceptedthatthespecicationrangeequalstheacceptancerangeifagivenconditionconsideringuncertaintyismet.Inthiscase,theinternationallyrecognizedacceptancecriterionisISO/TR14253-6:2012.(Fig.2)ThefollowingdescribesthestandardinspectionmethodincludingtherevisedcontentofJIS2016.Fig.1InstrumentalerrorJISB7507:1993orearlierSpecificationrangeNon-conformityrangeConformityrangeNon-conformityrangeAcceptancerangeUncertaintyisnotincludedinjudgmentSpecificationrange=AcceptancerangeFig.2Maximumpermissibleerror(MPE)JISB7507:2016(ISO/TR14253-6:2012)Non-conformityrangeSpecificationrangeConformityrangeNon-conformityrange(Rejected)UUUncertaintyrangeAcceptance(Rejected)UUUncertaintyrangeWhenaconditionconsideringuncertaintyissatisfiedSpecificationrange=ConformityrangeMaximumpermissibleerrorofpartialmeasuringsurfacecontacterrorEMPE[JISB7507:2016]Thepartialmeasuringsurfacecontacterrorofacaliperisanindicationerrorappliedtooutsidemeasurement.Table1showstheMaximumpermissibleerrorEMPEforvariousmeasuringrangesandgraduation/resolutionofacaliper.Thevaluecanbeobtainedbyinsertingagaugeblock(oranequivalentstandard)betweentheoutsidemeasuringsurfaces(Fig.3),measuringitatarbitrarypositionsbetweenthejawsandthensubtractingthedimensionofthegagefromthemaximumorminimumindicatedvalue.04-45Thescaleshifterrorinacaliperisanindicationerroroftheinsidemeasurement,depthmeasurement,etc.,ifmeasuringsurfacesotherthantheoutsidemeasuringsurfacesareused.TheMaximumpermissibleerrorSMPEoftheindicationvalueforinsidemeasurementisgiveninTable1.TheMaximumpermissibleerrorSMPEofdepthmeasurementisobtainedbyadding0.02mmtoavalueinTable1.Theindicationerrorforinsidemeasurementcanbeobtainedbyusinggaugeblocks(orequivalentstandards)andstandardjawsfromanaccessorysettoformaccurateinsidedimensionsforcalibration(Fig.4),withtheerrorbeinggivenbytheindicatedvalueminusthegaugeblocksize.Table1:MaximumpermissibleerrorEMPEofpartialmeasuringsurfacecontacterrorinaconventionalcaliperMeasurementrange50orlessOver50,100orlessOver100,200orlessOver200,300orlessScaleinterval,graduationorresolutionUnit:mm0.05±0.05±0.06±0.07±0.080.02±0.02±0.03±0.04Note:EMPEincludesthemeasurementerrorarisingfromthestraightness,flatnessandparallelismofthemeasuringsurfaces.Fig.3:DeterminingpartialmeasuringsurfacecontacterrorGaugeblockFig.4:DeterminingscaleshifterrorGaugeblockThe“Instrumentalerror”indicatingtheindicationerrorofJIShasbeenchangedto“Maximumpermissibleerror(MPE)ofindication”forthefollowingthreemodels:•VernierCaliperSERIES530—Standardmodeldescribedonpage04-8(530-101530-108530-109)•VernierCaliperSERIES532—withfineadjustmentdescribedonpage04-10(Allmodels)•VernierCaliperSERIES531—withthumbgripdescribedonpage04-11(Allmodels)
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