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1、附录附录1英文原文BasicMachiningOperationsandCuttingTechnologyBasicMachiningOperationsMachinetoolshaveevolvedfromtheearlyfoot-poweredlathesoftheEgyptiansandJohnWilkinson'sboringmill.Theyaredesignedtoproviderigidsupportforboththeworkpieceandthecuttingtoolandcanpreciselycontroltheirrelat

2、ivepositionsandthevelocityofthetoolwithrespecttotheworkpiece.Basically,inmetalcutting,asharpenedwedge-shapedtoolremovesarathernarrowstripofmetalfromthesurfaceofaductileworkpieceintheformofaseverelydeformedchip.Thechipisawasteproductthatisconsiderablyshorterthantheworkpiecefrom

3、whichitcamebutwithacorrespondingincreaseinthicknessoftheuncutchip.Thegeometricalshapeofworkpiecedependsontheshapeofthetoolanditspathduringthemachiningoperation.Mostmachiningoperationsproducepartsofdifferinggeometry.Ifaroughcylindricalworkpiecerevolvesaboutacentralaxisandthetoo

4、lpenetratesbeneathitssurfaceandtravelsparalleltothecenterofrotation,asurfaceofrevolutionisproduced,andtheoperationiscalledturning.Ifahollowtubeismachinedontheinsideinasimilarmanner,theoperationiscalledboring.Producinganexternalconicalsurfaceuniformlyvaryingdiameteriscalledtape

5、rturning,ifthetoolpointtravelsinapathofvaryingradius,acontouredsurfacelikethatofabowlingpincanbeproduced;or,ifthepieceisshortenoughandthesupportissufficientlyrigid,acontouredsurfacecouldbeproducedbyfeedingashapedtoolnormaltotheaxisofrotation.Shorttaperedorcylindricalsurfacesco

6、uldalsobecontourformed.Flatorplanesurfacesarefrequentlyrequired.Theycanbegeneratedbyradialturningorfacing,inwhichthetoolpointmovesnormaltotheaxisofrotation.Inothercases,itismoreconvenienttoholdtheworkpiecesteadyandreciprocatethetoolacrossitinaseriesofstraight-linecutswithacros

7、swisefeedincrementbeforeeachcuttingstroke.Thisoperationiscalledplanningandiscarriedoutonashaper.Forlargerpiecesitiseasiertokeepthetoolstationaryanddrawtheworkpieceunderitasinplanning.Thetoolisfedateachreciprocation.Contouredsurfacescanbeproducedbyusingshapedtools.Multiple-edge

8、dtoolscanalsobeused.Drillingusesatwin-edgedflutedtoolforholes