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1、resourcesforyourdesk,workbenchorpocket. BesuretocheckoutourGD&TTips!Straightness-aconditionwhereanelementofasurfaceoranaxisisastraightline. Flatness-istheconditionofasurfacehavingallelementsinoneplane. Roundness-describestheconditiononasurfaceofrevolution(cylinder,cone,sphere)where
2、allpointsofthesurfaceintersectedbyanyplane. Cylindricity-describesaconditionofasurfaceofrevolutioninwhichallpointsofasurfaceareequidistantfromacommonaxis. ProfileofaLine-istheconditionpermittingauniformamountofprofilevariation,etherunilaterallyorbilaterally,alongalineelementofafea
3、ture. ProfileofaSurface-istheconditionpermittingauniformamountofprofilevariation,etherunilaterallyorbilaterally,onasurface. AllAroundSymbol-indicatingthatatoleranceappliestosurfacesallaroundthepart. Angularity-istheconditionofasurface,axis,orcenterplane,whichisataspecifiedanglefrom
4、adatumplaneoraxis. Perpendicularity-istheconditionofasurface,axis,orline,whichis90deg.Fromadatumplaneoradatumaxis. Parallelism-istheconditionofasurface,line,oraxis,whichisequidistantatallpointsfromadatumplaneoraxis. PositionTolerance-definesazonewithinwhichtheaxisorcenterplaneofafe
5、atureispermittedtovaryfromtrue(theoreticallyexact)position. Concentricity-describesaconditioninwhichtwoormorefeatures,inanycombination,haveacommonaxis. Symmetry-isaconditioninwhichafeature(orfeatures)issymmetricallydisposedaboutthecenterplaneofadatumfeature. Runout-isthecompositede
6、viationfromthedesiredformofapartsurfaceofrevolutionthroughonfullrotation(360deg)ofthepartonadatumaxis. TotalRunout-isthesimultaneouscompositecontrolofallelementsofasurfaceatallcircularandprofilemeasuringpositionsasthepartisrotatedthrough360. MaximumMaterialCondition(MMC)-isthatcon
7、ditionofapartfeaturewhereinitcontainsthemaximumamountofmaterialwithinthestatedlimitsofsize.Thatis:minimumholesizeandmaximumshaftsize. LeastMaterialCondition(LMC)-impliesthatconditionofapartfeatureofsizewhereinitcontainstheleast(minimum)amountofmaterial,examples,largestholesizeandsma
8、llestshaftsi
