Ford-福特GDT形位公差培训材料-全集

GD&TforBody1GD&TforBodyEngineeringGD&TforBody1GD&TforBodyEnCoursecontentIntroductiontoGD&T5StepProcess2GD&TforBodyEngineeringCoursecontentIntroductiontoIntroductionWhatisGD&THowitaffectsFordMotorCompany3GD&TforBodyEngineeringIntroductionWhatisGD&T3GD&TWhatisGD&TGeometricDimensioningandTolerancingisatechnicaldatabasethroughwhichourProductDesignandManufacturingOrganisationscantalktooneanotherviaProductData,whetheronpaperorthecomputergraphicsscreen

Itistheengineeringproductdefinitionstandardthatgeometricallydescribesdesignintentandprovidesthedocumentationbaseforthedesignofthequalityandproductionsystem.

ItisatechniqueofcommunicationbetweenProductEngineeringandManufacturingEngineeringthatpromotesauniforminterpretationoftherequirementsformakingacomponent.4GD&TforBodyEngineeringWhatisGD&TGeometricDimensioWhatisGD&TGDTprovidesthedimensionsofthecomponentandthetolerancesinalanguagethateliminatesconfusingandinconsistentnotes,datumlines,andlocationpointidentifications,andreplacesthemwithstandardsymbolsthatrefertoauniversalcode.

Thiscodedescribesthedimensionsandtolerancesofthecomponentwithreferencetotherelationshipsofthefeaturestoeachotherandtheirfunctionalinterfaceswithmatingparts,assemblies,etc.5GD&TforBodyEngineeringWhatisGD&TGDTprovidesthedAuthorisationIn1990FordWorld-wideadoptedtheAmericanNationalStandardforDimensioningandTolerancing,currentlytheASMEY14.5M1994.TheauthorisationfortheaboveisdocumentedinStandardD-1oftheFordEngineeringCADandDraftingStandardsandisreferencedonallourreleaseddata.

ThisinformationcanbeaccessedviaFordintranet;

www-wise.ford/non-regulatory.html

TheabovedocumentalsocontainsanelectroniccopyoftheASMEY14.5M1994DimensioningandTolerancingStandard.6GD&TforBodyEngineeringAuthorisationIn1990FordWorlApplicationTheapplicationofGDTisinitiallytheresponsibilityoftherelevantComponentEngineer,howeverteamworkisthekeytothecorrectapplicationthroughthecomponentCoreTeam.

Thisprovidestheopportunityforalldisciplinestocontributetheirpartofthetotaldesignpackage.

Itensurespartdatawillsatisfydesignintentaswellasmanufacturingandinspectionrequirementsbasedonfunction,machinecapabilityandavailabletechnology.7GD&TforBodyEngineeringApplicationTheapplicationofApplicationItprovidestheopportunityforproperDatumselectionandhasthepotentialtosignificantlyreduceproductchanges,especiallythosechangesfollowingfinalproductrelease.

TheCoreTeamshouldconsistataminimumofrepresentativesfromProductEngineering,DesignEngineering,ManufacturingEngineering,andQualityEngineering.8GD&TforBodyEngineeringApplicationItprovidestheoppMoreinformationFordEngineeringCADandDraftingStandards

www-wise.ford/non-regulatory.htmlGDTApplication

cadmethods.ford9GD&TforBodyEngineeringMoreinformationFordEngineeriHowGD&TRelatestoFordThecorrectapplicationhasthepotentialto;InfluenceFitandFinishReduceReworksIncreaseReliabilityAffectsAssemblyProcessReducecost10GD&TforBodyEngineeringHowGD&TRelatestoFordThecoThe5StepProcess1234511GD&TforBodyEngineeringThe5StepProcess1234511GD&T5StepProcess1 UtilisethenewDesignConcept2 EstablishmentoftheDatumReferenceFrame3 EstablishGD&TControls4 EstablishTolerances5 FinalApprovalofGD&TonCadData12GD&TforBodyEngineering5StepProcess1 UtilisetheneStep1Utilisenewdesignconcept13GD&TforBodyEngineeringStep1UtilisenewdesignconceUtilisenewdesignconceptThe1ststepinvolvesmakingdecisionsatthebasicdesignstagethatwillultimatelyeffectthedesign,manufactureandverificationofthefinalcomponent.

ThiscanonlybesuccessfullyachievedbytherelevantPDrepresentativeattendingtheMasterControlPlan(MCP)Meetings.14GD&TforBodyEngineeringUtilisenewdesignconceptTheMasterControlPlanWhatisthepurposeoftheMCPmeetinginrelationtoPDToestablishacommonunderstandingfortheverificationprocessofthemajorpanels,e.g.Bodyside,Hood,DeckLid,Door,Roof,Underbody,etc.Toobtainagreementatanearlystageofthedesignforthedatumreferenceframe,dieapproach,etc.

WhoattendstheMeetingPDandManufacturing,i.e.BodyEngineering,DCD,Stamping,BodyandAssembly.15GD&TforBodyEngineeringMasterControlPlanWhatistheMasterControlPlanWhenshouldtheMeetingtakeplace.Initialdesignconceptstage,knowingthecomponentsparameterssuchassizeandfunction

Currentmethodsuse;Pastevidence,pastexperience,cansometimeshinderratherthanassistthenewdesignconcept

ResultofmeetingMaybedocumentedinCAD,orpaperform16GD&TforBodyEngineeringMasterControlPlanWhenshouldStep2EstablishDatumReferenceFrame17GD&TforBodyEngineeringStep2EstablishDatumReferencEstablishDatumReferenceFrameAspartoftheMasterControlPlan(MCP)Processmeeting,BodyEngineeringandManufacturingagreedtothedefinitionoftheDatumFeaturesandtheirlocation.

PDhaveOwnershipoftheDatumFeatures.18GD&TforBodyEngineeringEstablishDatumReferenceFramDatumReferenceFrame

(ReferencePocketGuide,Page8)ConsistsofasetofthreemutuallyperpendicularplanesThereferenceframeexistsintheoryonlyandisnotonthepartSufficientdatumfeaturesareusedtopositionthepartinrelationtotheDatumReferenceFrame.19GD&TforBodyEngineeringDatumReferenceFrame

(RefereDatumFeaturesAnactualfeatureofthepartusedtostage/positionthepartintheequipmentforpurposesofrelatingitsgeometrytotheDatumReferenceFrame.20GD&TforBodyEngineeringDatumFeaturesAnactualfeaturPrimaryDatumPlaneAchievedbyestablishingaminimumofthreePointstodefineaplane

21GD&TforBodyEngineeringPrimaryDatumPlaneAchievedbyPrimaryDatumPlanePrimaryDatumPlaneshouldbeParalleltoDiePlane

22GD&TforBodyEngineeringPrimaryDatumPlanePrimaryDatPrimaryDatumPlaneWhenDatumTargetAreasdefiningPrimaryDatumPlanearenotononesingleplanarsurface,theymustbecontrolledonetoanotherusingthePROFILEofaSURFACEgeometriccontrol.23GD&TforBodyEngineeringPrimaryDatumPlaneWhenDatumSupportingapanelonlyonthedesignatedDatumTargetAreas,effectivelyremoves3degreesoffreedom,i.e.1Linearand2Rotational.24GD&TforBodyEngineeringSupportingapanelonlyontheDatumTargetAreasDatumTargetAreasshouldwhereverpossiblebeplanarandparalleltothedieplane.PrimaryDatumPlane25GD&TforBodyEngineeringDatumTargetAreasDatumTargetDatumTargetAreasDedicatedDatumTargetAreasmakesboththepart,andgauge/fixturemorerobust,costeffectiveandImprovesrepeatability26GD&TforBodyEngineeringDatumTargetAreasDedicatedDaSecondaryDatumFeatureGenerallyaDatumFeatureofSizeisused,i.e.SinglecircularHole,positionedonasurfacethatisparalleltothePrimarydatumPlane,andisultimatelyusedasafourwaylocator.

27GD&TforBodyEngineeringSecondaryDatumFeatureGeneralSecondaryDatumFeatureControlledrelativetothePrimaryDatumPlaneusingtheGeometriccontrolPERPENDICULARITY.28GD&TforBodyEngineeringSecondaryDatumFeatureControlSecondaryDatumFeatureTheintersectionofthederivedaxisofthefeatureperpendiculartothePrimaryDatumPlane,andthedesignsideofthecomponentisthelocaloriginofallbasicdimensions;0,0,029GD&TforBodyEngineeringSecondaryDatumFeatureTheintSupportingapanelonthedesignatedDatumTargetAreas,andusingthefourwaylocatorremovesanother2Lineardegreesoffreedom,resultinginall3Linear,and2Rotationaldegreesoffreedomconstrained.30GD&TforBodyEngineeringSupportingapanelonthedesiTertiaryDatumFeatureGenerallythewidthofa

SlottedFeatureofSize

isusedasa

twoway

locator.31GD&TforBodyEngineeringTertiaryDatumFeatureGenerallTertiaryDatumFeatureToeliminatetoleranceofDatumShiftononeofthetheoreticalaxisofthecartesiancoordinatesystem,theorientationoftheslot(length)shouldpointtotheaxisoftheSecondaryDatumFeature.32GD&TforBodyEngineeringTertiaryDatumFeatureToelimiTertiaryDatumFeatureTheslottedfeature’swidthmustbepositionedonasurfacewiththeslotwidthaxisparalleltotheprimarydatumplane,andcontrolledusingthegeometriccontrolofPOSITIONandnominatedastheTertiaryDatumFeature.33GD&TforBodyEngineeringTertiaryDatumFeatureTheslotSupportingapanelonthedesignatedDatumTargetAreas,usingthefourway,andtwowaylocatorsremovesallsixdegreesoffreedom.34GD&TforBodyEngineeringSupportingapanelonthedesiStep3EstablishGD&TControls35GD&TforBodyEngineeringStep3EstablishGD&TControls3CommonTermsandDefinitionsReferencePocketGuidePage236GD&TforBodyEngineeringCommonTermsandDefinitionsReMaterialConditionsMMC MaximumMaterialConditionLMC LeastMaterialConditionRFS RegardlessofFeatureSizeVirtualCondition37GD&TforBodyEngineeringMaterialConditionsMMC MaximumMaximumMaterialConditionTheconditioninwhichafeatureofsizecontainsthemaximumamountofmaterialwithinthestatedlimitsofsize.

TheHeaviestPart

MinimumHoleDiameter(10.0)

MaximumShaftDiameter(11.0)M10.0+1.0038GD&TforBodyEngineeringMaximumMaterialConditionTheLeastMaterialConditionTheconditioninwhichafeatureofsizecontainstheleastamountofmaterialwithinthestatedlimitsofsize.

TheLightestpart

MaximumHoleDiameter(11.0)

MinimumShaftDiameter(10.0)TodatenoapplicationintheFeatureControlFrameforthissymbolhasbeenidentifiedinBodyEngineering.L10.0+1.0039GD&TforBodyEngineeringLeastMaterialConditionThecoRegardlessofFeatureSizeThereisnosymbolforRegardlessofFeatureSize.IfamaterialmodifierisnotusedthenRegardlessofFeatureSizeisassumed.

Thetermusedtoindicatethatageometrictoleranceordatumreferenceappliesatanyincrementofsizeofthefeaturewithinitssizetolerance

RegardlessofFeatureSizeisexpensivetoverify,andrarelyreflectstherelevantfeaturefunction,andthereforeshouldnotbeusedinaBodyapplicationwithouttheagreementoftheentirecoreteam.10.0+1.001.040GD&TforBodyEngineeringRegardlessofFeatureSizeTherVirtualConditionAconstantBoundarygeneratedbythecollectiveeffectsofasizefeature’sspecifiedMMCorLMCmaterialconditionandthegeometrictoleranceforthatcondition.

TheVIRTUALCONDITIONoffeaturesofmatingpartsmustbematched,guaranteeingcomponentfeaturesattheirworstcaseforassemblywillalwaysassemble.

TheVirtualconditionenvelopeistheworstconditionofferedtothematingpart.41GD&TforBodyEngineeringVirtualConditionAconstantBVirtualCondition(Shaft)Virtualcondition(Shaft)=MMC+Tolerancezonevalue=12.0MMCLMCM1.010.0+1.0-0=10.0=11.0VirtualCondition42GD&TforBodyEngineeringVirtualCondition(Shaft)VirtuVirtualCondition(Hole)MMCLMCM1.010.0+1.0-0=11.0=10.0VirtualConditionVirtualcondition(Hole)=MMC-Tolerancezonevalue=9.043GD&TforBodyEngineeringVirtualCondition(Hole)MMCLMCGeometricControlsReferencePocketGuidePage144GD&TforBodyEngineeringGeometricControlsReferencePoFeatureControlFrame

(ReferencePocketGuide,page3)MAB0.5MCMGeometriccharacteristicsymbols,thetolerancevalue,MaterialModifiers,andDatumsofReference,whereapplicable,arecombinedinafeaturecontrolframetoexpressageometrictolerance.45GD&TforBodyEngineeringFeatureControlFrame

(RefereGeometricCharacteristicSymbolMaterialConditionSymbolWhereapplicableMAB0.5MCMToleranceToleranceZoneShapewhereapplicableDatumReferenceLetters46GD&TforBodyEngineeringGeometricMaterialConditionSyGeometricControlsEachfeatureofthecomponentmustbecontrolledforSIZE,FORM,ORIENTATIONandLOCATION.IntheAmericanNationalStandardtherearefourteengeometriccontrols.BodyEngineeringusejustthree;

1 PERPENDICULARITY

2 POSITION

3 PROFILE47GD&TforBodyEngineeringGeometricControlsEachfeaturePERPENDICULARITYReferencePocketGuidePage2948GD&TforBodyEngineeringPERPENDICULARITYReferencePockPERPENDICULARITYThemainApplicationforPERPENDICULARITYwithinBodyEngineeringistocontrolasingleSecondaryDatumFeatureofsize(ahole)tobeperpendiculartothePrimaryDatumPlane.Generallyusedonlyoncewithineachcomponenttodefinethesecondarydatumfeature.Anyotheruseofthiscontrol

forotherfeatureswouldbean

additionalrequirement,because

PERPENDICULARITYdoesnot

implyanylocation

49GD&TforBodyEngineeringPERPENDICULARITYThemainAppliLMCTheCylindrical

ToleranceZonediameterisdependantontheactualfeaturesizeBAPERPENDICULARITYMA019.0+0.10Acylindricaltolerancezoneperpendiculartoadatumplanewithinwhichtheaxisofafeaturemustlie.50GD&TforBodyEngineeringLMCTheCylindrical

TolerancePOSITIONReferencePocketGuide

Page3351GD&TforBodyEngineeringPOSITIONReferencePocketGuidePOSITIONDefinitionPositionToleranceZonesZeroatMMCConceptBoundaryConceptCompositeToleranceZonesProjectedToleranceZone52GD&TforBodyEngineeringPOSITIONDefinition52GD&TforBThetermtodescribetheperfect(theoreticalexact)locationofindividualfeaturesinrelationshipwithadatumreferenceorotherfeature(s).

IngeneralthePOSITIONcontrolisusedtolocateuniformfeaturesofsize,e.g.holes,shafts,slotsetc.

POSITION53GD&TforBodyEngineeringThetermtodescribetheperfeVerificationAswithallFeaturesofSize;

Firsttobeverifiedisthatthetopandbottomlimitsofsizehavenotbeenviolated(Taylor’sPrinciple).AfullformcheckattheMMCandatwopointedinstrumentcheckattheLMC.

Secondlythefeature’s“Position”mustbeverified.

GD&Tdoesnotdictatethemethodofverification.Thedecisiononthegaugingtechniqueemployedistheresponsibilityofthecoreteam.54GD&TforBodyEngineeringVerificationAswithallFeaturPositionToleranceZones55GD&TforBodyEngineeringPositionToleranceZones55GD&TPositionalToleranceZone1

(Cylindrical)20.0+1.0

0TospecifyaCylindricalToleranceZone,adiametersignmustprecedethetolerancevalue,followedbythematerialModifierMMCunlessRegardlessofFeatureSizeisintended.M0.5Acylindricalzonewithinwhichthecentreaxisofafeatureofsizeispermittedtovaryfromitstrue(theoreticallyexact)position.56GD&TforBodyEngineeringPositionalToleranceZone1

(CPositionalToleranceZone2

(NonCylindrical)Azonewithinwhichthecentre,axis,ofcentreplaneofafeatureofsizeispermittedtovaryfromitstrue(theoreticallyexact)position.20.0+2.0

0ThetolerancevalueisfollowedbythematerialModifierMMCunlessRegardlessofsizeisintended.TospecifyatotalwidthToleranceZone,Nodiametersymbolprecedesthetolerancevalue.M0.557GD&TforBodyEngineeringPositionalToleranceZone2

(NBOUNDARYReferencePocketGuide

Page3758GD&TforBodyEngineeringBOUNDARYReferencePocketGuideBOUNDARYInBodyEngineeringcontrollingthecentreplaneofaslottedfeatureisrarelyapriority.59GD&TforBodyEngineeringBOUNDARYInBodyEngineeringcoAsnoDiametersymbolprecedesthepositionaltolerance,anoncylindricalzoneisinferred.BOUNDARYBOUNDARYBOUNDARYWhatweareinterestediniscontrollingtheBOUNDARYofthefeature.12.0+2.0

02.0M1.0M5.0+1.0

060GD&TforBodyEngineeringAsnoDiametersymbolprecedesBOUNDARY5.0MMCWidthofHole

-1.0PositionalTolerance4.0WideBoundary4BOUNDARY1.0MBOUNDARY5.0+1.0

0VirtualCondition12.0MMCWidthofHole

-2.0PositionalTolerance10.0WideBoundary102.0M12.0+2.0

061GD&TforBodyEngineeringBOUNDARY5.0MMCWidthofHolBOUNDARYNoportionoftheslotsurfacesarepermittedtoliewithintheareadescribedbytheVirtualConditionwhenthepartispositionedwithintheDatumReferenceFrameThePOSITIONcontrol+BOUNDARYcontrolsbothLocationandOrientation12.0+2.0

02.0MBOUNDARY1.0MBOUNDARY5.0+1.0

062GD&TforBodyEngineeringBOUNDARYNoportionoftheslotBOUNDARY12.0+2.0

02.0MBOUNDARY2.0MBOUNDARY5.0+1.0

0IfthesamePositionalTolerancevalueappliestoboththeLengthandWidthlimitsofsize,thentheFeatureControlFrameisseparatedfromtheLimitsofSize,andpointsdirectlytotheslottedfeature.63GD&TforBodyEngineeringBOUNDARY12.0+2.002.0MBOUBOUNDARY12.0+2.0

02.0MBOUNDARY5.0+1.0

0IfthesamePositionalTolerancevalueappliestoboththeLengthandWidthlimitsofsize,thentheFeatureControlFrameisseparatedfromtheLimitsofSize,andpointsdirectlytotheslottedfeature.64GD&TforBodyEngineeringBOUNDARY12.0+2.002.0MBOUBOUNDARYTheBOUNDARYnoteonlyappliestononcylindricalfeatures.ThePOSITIONcontrol+BOUNDARYcontrolsbothLocationandOrientationInthiscasethewordBOUNDARYmustbeaddedbelowtheFCFandthematerialModifierMMCspecifiedafterthePOSITIONtolerancevalue.NodiametersymbolprecedesthetolerancevalueintheFeatureControlFrameThepositionaltolerancespecifiedforthelengthmaydifferfromthatspecifiedforthewidth.ToSummarise65GD&TforBodyEngineeringBOUNDARYTheBOUNDARYnoteonlZeroatMMCconceptReferencePocketGuidePage4466GD&TforBodyEngineeringZeroatMMCconceptReferencePZeroatMMCconceptTheZeroatMMCconceptappliesonlytofeatureswho’ssolefunctionisCLEARANCE67GD&TforBodyEngineeringZeroatMMCconceptTheZeroatM10.0L11.51.02.59.010.310.510.89.09.09.09.0ActualMatingEnvelopeToleranceZone(Dia)VirtualCondition10.0+1.50Whatisthesmallestdiameterholepermissible?Question?10AnswerExampleofcurrentspecificationM1.0AMMBC68GD&TforBodyEngineeringM10.0L11.51.02.59.010.310.510.ExampleofcurrentspecificationYesAnswerQuestion?Ifafeatureofthepartwasmeasured,andtheholewasfoundtobeDia9.6,wouldthispartbereject?M10.0L11.51.02.59.010.310.89.09.09.09.09.0ActualMatingEnvelopeToleranceZone(Dia)VirtualCondition10.0+1.50M1.0AMMBC69GD&TforBodyEngineeringExampleofcurrentspecificatiExampleofcurrentspecificationBut,wouldtherejectedpartbefunctional?Question?AnswerTomakethepartacceptablewewouldneedtochangethedataspecification.10.0+1.50Ifthepartmeetsthefunctionalgaugerequirements,weknowthepartisfunctional.Theparthasbeenrejectedbecauseoffeaturesizealone.Thereforeitmusthavebeenmanufacturedtoatighterspecificationthanthatstatedonthedata.M1.0AMMBC70GD&TforBodyEngineeringExampleofcurrentspecificatiExampleofcurrentspecificationWhatneedstochange?Question?Thespecificationfortheholeneedstochange,byadoptingthe“ZeroatMMC”conceptAnswerM10.0L11.51.02.59.010.310.89.09.09.09.09.0ActualMatingEnvelopeToleranceZone(Dia)VirtualCondition10.0+1.50M1.0AMMBC71GD&TforBodyEngineeringExampleofcurrentspecificatiZeroatMMCconcept+2.509.0Example:Tocomplywiththe“ZeroatMMC”conceptforclearanceholes;TheSpecifiedvalueoftheFeatureofSizeismodifiedtoequaltheVirtualCondition,i.e.(MMC-PositionalTolerance).Thegeometrictolerancevalueisincorporatedintothefeatureslimitsofsize10.0+1.50M1.0AMMBCAzerotoleranceisspecifiedintheFeatureControlFrame,andthematerialmodifierMMCMUSTfollowthezerotolerancevalue.M0AMMBC72GD&TforBodyEngineeringZeroatMMCconcept+2.509.0EM9.00ZeroatMMCconcept10.0L11.51.02.59.09.010.39.09.010.89.09.0ActualMatingEnvelopeToleranceZone(Dia)VirtualCondition9.09.09.09.0TheZeroatMMCconceptgivesManufacturingtheFULLrangeoftoleranceavailable,andsincetheMMCsizeisnowequaltotheVIRTUALCONDITION,noseparateMMCfeaturesizeverificationisrequired.(TaylorsPrinciple)TheLMCfeaturesizemuststillbefunctionallyderivedandverified9.0+2.50M0ABC73GD&TforBodyEngineeringM9.00ZeroatThespecifiedFeatureofSizeisnotthetargetsizeformanufacturing.ZeroatMMCconceptThetoleranceavailableisdependantontheFeatureofSizeM9.00ThenearertheactualpunchsizeistotheLMC,thelargertheToleranceofPosition10.0L11.51.02.59.09.010.39.09.010.89.09.0ActualMatingEnvelopeToleranceZone(Dia)VirtualCondition9.09.09.09.0M09.0+2.50VIRTUALCONDITION&MMCLMCFEATURESIZE74GD&TforBodyEngineeringThespecifiedFeatureofSizeStandardPunchSizeM09.0+2.50PunchdiameterwillbeLMCminus0.1mmroundedupordownM9.0010.0L11.51.02.59.09.010.39.09.010.89.09.0ActualMatingEnvelopeToleranceZone(Dia)VirtualCondition9.09.09.09.015.2715.1715.212.7612.6612.711.511.411.4LMC-0.1mmExamplePunchDia.75GD&TforBodyEngineeringStandardPunchSizeM09.0+2.CompositePositionalTolerancesReferencePocketGuide

Page4576GD&TforBodyEngineeringCompositePositionalToleranceCompositePositionalTolerances

(Forgroupsofholes)MA2.020.0+0.30M0.5MBMCA3xFIXHOLESTheuppersegmentisreferredtoasthe“PatternLocatingToleranceZoneFramework”(PLTZF)Thelowersegmentisreferredtoasthe“FeatureRelatingToleranceZoneFramework”(FRTZF)77GD&TforBodyEngineeringCompositePositionalToleranceCompositePositionalTolerancesActualHoleFeatureRelatingtoleranceZoneMA2.0M0.5MBMCAPatternLocatingToleranceZone78GD&TforBodyEngineeringCompositePositionalToleranceCompositePositionalTolerancesMA2.0M0.5MBMCA79GD&TforBodyEngineeringCompositePositionalToleranceCompositePositionalTolerancesMA2.0M0.5MBMCAThecontrolrequiresthateachactualfeatureaxismustliewithinthespecifiedtolerancezonesofboththeupperandlowersegmentssimultaneously80GD&TforBodyEngineeringCompositePositionalToleranceCompositePositionalTolerancesMA2.0M0.5MBMCAThecontrolrequiresthateachactualfeatureaxismustliewithinthespecifiedtolerancezonesofboththeupperandlowersegmentssimultaneously25.025.081GD&TforBodyEngineeringCompositePositionalToleranceCompositePositionalTolerancesItsapplicationissupportedbytheentirecoreteam.

Thecontrolreflectsthepartfeaturemanufacturingprocess.

Itwillbeverifiedinfulldownstream.

Theadded-oncosttotheverificationprocessisjustifiedbytherequiredfeaturefunction.Beforespecifyingthiscontrolverifythat;82GD&TforBodyEngineeringCompositePositionalToleranceProjectedToleranceZoneReferencePocketGuide

Page4383GD&TforBodyEngineeringProjectedToleranceZoneRefereProjectedToleranceZoneTheprojectedtolerancezoneprincipleshouldbeappliedtoassembliesthatcontainmatingpartsofsubstantialthicknessandareconstrainedwithfastenerssuchasscrewsintappedholes,studsordowelpins(termedfixedfasteners).84GD&TforBodyEngineeringProjectedToleranceZoneTheprFollowedbythedimensionindicatingtheminimumheightofthetolerancezoneProjectedToleranceZoneThePROJECTEDToleranceZoneisinvokedby

usingthesymbolintheFeatureControlFramePDIRECTIONOFPROJECTEDZONEM0.5P43.2ABMCMM12x1.75MINOR43.285GD&TforBodyEngineeringFollowedbythedimensionindiProjectedToleranceZoneTheProjectedToleranceZoneeffectivelytransfersthetolerancezonefrominsidethetappedhole/dowelholeoutintothespaceoccupiedbythebodyofthebolt/dowelpinafterassembly86GD&TforBodyEngineeringProjectedToleranceZoneThePrPROFILEReferencePocketGuide

Page2087GD&TforBodyEngineeringPROFILEReferencePocketGuide

PROFILEProfileisthemostversatileandprobablythemostpowerfulofthegeometricControls.88GD&TforBodyEngineeringPROFILEProfileisthemostverPROFILEThetrueprofileisdefinedbythetheoreticallyexactCADmodel(basicdimensions).89GD&TforBodyEngineeringPROFILEThetrueprofileisdePROFILECanbespecifiedwithorwithoutadatumofreferenceIfthecontrolhasnodatumofreferencethenthetolerancevalueappliestothefeaturestruebasicprofileandnoorientationorlocationisimplied.If

theprofilecontrolisreferencedtothedatumfeaturesofthecomponentthentheconsideredfeatureisfullycontrolledforsize,form,orientationandlocation90GD&TforBodyEngineeringPROFILECanbespecifiedwithoPROFILEProfileisseparatedintotwotypesofcontrolsProfileofaLineProfileofaSurface

TherearethreemethodsofestablishingthetolerancezoneBilateral(Defaultunlessotherwisestated)UnilateralSpecialCase91GD&TforBodyEngineeringPROFILEProfileisseparatedinProfileofaLine2.0TheToleranceestablishesauniformtwo-dimensionalzonelimitedbytwoparallelzonelinesextendingalongthelengthoftheconsideredfeature.TheToleranceisappliedNormal/Perpendiculartothetrueprofileatallpointsalongtheprofile.TheactuallineelementmustliewithintheSpecifiedToleranceZone.2.0(Bilateral)92GD&TforBodyEngineeringProfileofaLine2.0TheToleraProfileofaSurfaceTheToleranceestablishesauniformthree-dimensionalzonecontainedbetweentwoenvelopesurfacesseparatedbythespecifiedtolerance.Thezoneextendsalongthelengthandwidth,orcircumferenceoftheconsideredsurface.Thetoleranceisappliednormaltothetruebasicprofileoftheconsideredsurface.2.02.093GD&TforBodyEngineeringProfileofaSurfaceTheToleraUnilateralTolerance2.0TOL.APPLIESINDIRECTIONLMCHOLE2.0TOL.APPLIESINDIRECTIONMMCHOLEBASICPROFILE2.094GD&TforBodyEngineeringUnilateralTolerance2.0TOL.APUnilateralTolerance2.0TOL.APPLIESINMATERIALDIRECTIONMATERIALDIRECTIONToleranceZone95GD&TforBodyEngineeringUnilateralTolerance2.0TOL.AP