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GD&TforBodyGD&TforBodyEngineering2Coursecontent课程内容•IntroductiontoGD&T•GD&T介绍•5StepProcess•5步方法GD&TforBodyEngineering3Introduction介绍•WhatisGD&T•什么是GD&T•HowitaffectsFordMotorCompany•它如何让影响福特汽车公司GD&TforBodyEngineering4WhatisGD&T什么是GD&T•GeometricDimensioningandTolerancingisatechnicaldatabasethroughwhichourProductDesignandManufacturingOrganisationscantalktooneanotherviaProductData,whetheronpaperorthecomputergraphicsscreen几何尺寸公差是贯穿我们产品设计和生产制造的技术数据基础，无论是通过图纸或者是计算机上的图表，我们都能通过产品数据与其他人沟通。•Itistheengineeringproductdefinitionstandardthatgeometricallydescribesdesignintentandprovidesthedocumentationbaseforthedesignofthequalityandproductionsystem.工程产品定义标准，几何尺寸描述设计意图，并为品质设计和产品系统提供文件基准。•ItisatechniqueofcommunicationbetweenProductEngineeringandManufacturingEngineeringthatpromotesauniforminterpretationoftherequirementsformakingacomponent.•它是一种在产品工程和制造工程之间的技术交流，并促成一种针对零部件制造要求的唯一的解释。GD&TforBodyEngineering5WhatisGD&T什么是GD&T•GDTprovidesthedimensionsofthecomponentandthetolerancesinalanguagethateliminatesconfusingandinconsistentnotes,datumlines,andlocationpointidentifications,andreplacesthemwithstandardsymbolsthatrefertoauniversalcode.•GDT提供部件的尺寸和公差，用一种语言，它能够消除混淆和不一致的注释，基准线，定位点辨认，并且用与一种通用的代码相关的标准符号替换他们。•Thiscodedescribesthedimensionsandtolerancesofthecomponentwithreferencetotherelationshipsofthefeaturestoeachotherandtheirfunctionalinterfaceswithmatingparts,assemblies,etc.•代码描述了关于部件间相互关系的特征的尺寸和公差，和他们匹配的部件的功能界面，总成等。GD&TforBodyEngineering6Authorisation批准•In1990FordWorld-wideadoptedtheAmericanNationalStandardforDimensioningandTolerancing,currentlytheASMEY14.5M1994.TheauthorisationfortheaboveisdocumentedinStandardD-1oftheFordEngineeringCADandDraftingStandardsandisreferencedonallourreleaseddata.在1990福特全球范围内采用美国尺寸公差标准，目前的ASMEY14.5M1994。•ThisinformationcanbeaccessedviaFordintranet;•TheabovedocumentalsocontainsanelectroniccopyoftheASMEY14.5M1994DimensioningandTolerancingStandard.GD&TforBodyEngineering7Application•TheapplicationofGDTisinitiallytheresponsibilityoftherelevantComponentEngineer,howeverteamworkisthekeytothecorrectapplicationthroughthecomponentCoreTeam.•Thisprovidestheopportunityforalldisciplinestocontributetheirpartofthetotaldesignpackage.•Itensurespartdatawillsatisfydesignintentaswellasmanufacturingandinspectionrequirementsbasedonfunction,machinecapabilityandavailabletechnology.GD&TforBodyEngineering8Application•ItprovidestheopportunityforproperDatumselectionandhasthepotentialtosignificantlyreduceproductchanges,especiallythosechangesfollowingfinalproductrelease.•TheCoreTeamshouldconsistataminimumofrepresentativesfromProductEngineering,DesignEngineering,ManufacturingEngineering,andQualityEngineering.GD&TforBodyEngineering9Moreinformation•FordEngineeringCADandDraftingStandards•GDTApplication•InfluenceFitandFinish•ReduceReworks•IncreaseReliability•AffectsAssemblyProcess•ReducecostGD&TforBodyEngineering11The5StepProcess12345GD&TforBodyEngineering125StepProcess1UtilisethenewDesignConcept2EstablishmentoftheDatumReferenceFrame3EstablishGD&TControls4EstablishTolerances5FinalApprovalofGD&TonCadDataGD&TforBodyEngineering13Step1UtilisenewdesignconceptGD&TforBodyEngineering14Utilisenewdesignconcept•The1ststepinvolvesmakingdecisionsatthebasicdesignstagethatwillultimatelyeffectthedesign,manufactureandverificationofthefinalcomponent.•ThiscanonlybesuccessfullyachievedbytherelevantPDrepresentativeattendingtheMasterControlPlan(MCP)Meetings.GD&TforBodyEngineering15MasterControlPlanWhatisthepurposeoftheMCPmeetinginrelationtoPD•Toestablishacommonunderstandingfortheverificationprocessofthemajorpanels,e.g.Bodyside,Hood,DeckLid,Door,Roof,Underbody,etc.•Toobtainagreementatanearlystageofthedesignforthedatumreferenceframe,dieapproach,etc.WhoattendstheMeeting•PDandManufacturing,i.e.BodyEngineering,DCD,Stamping,BodyandAssembly.GD&TforBodyEngineering16MasterControlPlanWhenshouldtheMeetingtakeplace.•Initialdesignconceptstage,knowingthecomponentsparameterssuchassizeandfunctionCurrentmethodsuse;•Pastevidence,pastexperience,cansometimeshinderratherthanassistthenewdesignconceptResultofmeeting•MaybedocumentedinCAD,orpaperformGD&TforBodyEngineering17Step2EstablishDatumReferenceFrameGD&TforBodyEngineering18EstablishDatumReferenceFrame•AspartoftheMasterControlPlan(MCP)Processmeeting,BodyEngineeringandManufacturingagreedtothedefinitionoftheDatumFeaturesandtheirlocation.•PDhaveOwnershipoftheDatumFeatures.GD&TforBodyEngineering19DatumReferenceFrame(ReferencePocketGuide,Page8)ConsistsofasetofthreemutuallyperpendicularplanesThereferenceframeexistsintheoryonlyandisnotonthepartSufficientdatumfeaturesareusedtopositionthepartinrelationtotheDatumReferenceFrame.GD&TforBodyEngineering20DatumFeatures•Anactualfeatureofthepartusedtostage/positionthepartintheequipmentforpurposesofrelatingitsgeometrytotheDatumReferenceFrame.GD&TforBodyEngineering21PrimaryDatumPlane•Achievedbyestablishi