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1、resourcesforyourdesk,workbenchorpocket.BesuretocheckoutourGD&TTips!Straightness-aconditionwhereanelementofasurfaceoranaxisisastraight口line.Flatness-istheconditionofasurfacehavingallelementsinoneplane.oRoundness-describestheconditiononasurfaceofrevolution(cylinder,cone,sphere)whereallpointsofthesur
2、faceintersectedbyanyplane・QCylindricity-describesaconditionofasurfaceofrevolutioninwhichallpointsofasurfaceareequidistantfromacommonaxis.ProfileofaLine-istheconditionpermittingauniformamountofprofilevariation,etherunilaterallyorbilaterally,alongalineelementofafeature.aProfileofaSurface・isthecondit
3、ionpermittingauniformamountofprofilevariation,etherunilaterallyorbilaterally,onasurface.上iAllAroundSymbol-indicatingthatatoleranceappliestosurfacesallaroundthepart・Angularity・istheconditionofasurface,axis,orcenterplane,whichisataspecifiedanglefromadatumplaneoraxis.Perpendicularity-istheconditionof
4、asurface,axis,orline,whichis90deg.Fromadatumplaneoradatumaxis.〃Parallelism・istheconditionofasurface,line,oraxis,whichisequidistantatallpointsfromadatumplaneoraxis.PositionTolerance-definesazonewithinwhichtheaxisorcenterplaneofafeatureispermittedtovaryfromtrue(theoreticallyexact)position.◎Concentri
5、city-describesaconditioninwhichtwoormorefeatures,inanycombination,haveacommonaxis.Symmetry-isaconditioninwhichafeature(orfeatures)issymmetricallydisposedaboutthecenterplaneofadatumfeature・Runout-isthecompositedeviationfromthedesiredformofapartsurfaceofrevolutionthroughonfullrotation(360deg)ofthepa
6、rtonadatumaxis.TotalRunout・isthesimultaneouscompositecontrolofallelementsofasurfaceatallcircularandprofilemeasuringpositionsasthepartisrotatedthrough360.MaximumMaterialCondition(MMC)-isthatconditionofapartfeaturewhereinitcontainsthemaximumamountofmaterialwithinthestatedlimitsofsize.Thatis:minimumh
7、olesizeandmaximumshaftsize・©LeastMaterialCondition(LMC)-impliesthatconditionofapartfeatureofsizewhereinitcontainstheleast(minimum)amountofmaterial,examples,largestholesizeandsmallestshaftsize・Itisoppositetomaximu
