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MemoirsoftheFacultyofEngineeringKYUSHUUniversityTheIntroductionofMachiningT.L.NeoandK.S.LeeDepartmentofMechanicalandProductionEngineering,NationalUniversityofSingapore,SingaporeAbstractMachiningprocessisaprocessgeneratedshape,inthisprocess,Driversdeviceontheworkpiecematerialtobeintheformofchipremoval.Althoughinsomeoccasions,theworkpieceundernocircumstances,theuseofmobileequipmenttotheprocessing,However,themajorityofthemachiningisnotonlysupportingtheworkpiecealsosupportingtoolsandequipmenttocomplete.Keyword:introduction；machiningHaveashapeasaprocessingmethod,allmachiningprocessfortheproductionofthemostcommonlyusedandmostimportantmethod.Machiningprocessisaprocessgeneratedshape,inthisprocess,Driversdeviceontheworkpiecematerialtobeintheformofchipremoval.Althoughinsomeoccasions,theworkpieceundernocircumstances,theuseofmobileequipmenttotheprocessing,However,themajorityofthemachiningisnotonlysupportingtheworkpiecealsosupportingtoolsandequipmenttocomplete.Machiningknowtheprocesshastwoaspects.Smallgroupoflow-costproduction.Forcasting,forgingandmachiningpressure,everyproductionofaspecificshapeoftheworkpiece,evenaspareparts,almosthavetospendthehighcostofprocessing.Weldingtorelyontheshapeofthestructure,toalargeextent,dependoneffectiveintheformofrawmaterials.Ingeneral,throughtheuseofexpensiveequipmentandwithoutspecialprocessingconditions,canbealmostanytypeofrawmaterials,mechanicalprocessingtoconverttherawmaterialsprocessedintothearbitraryshapeofthestructure,aslongastheexternaldimensionslargeenough,itispossible.Becauseofaproductionofspareparts,evenwhenthepartsandstructureoftheproductionbatchsizesaresuitablefortheoriginalcasting,Forgingorpressureprocessingtoproduce,butusuallyprefermachining.Strictprecisionandgoodsurfacefinish,Machiningthesecondpurposeistheestablishmentofthehighprecisionandsurfacefinishpossibleonthebasisof.Manyparts,ifanyothermeansofproductionbelongingtothelarge-scaleproduction,WellMachiningisalow-toleranceandcanmeettherequirementsofsmallbatchproduction.Besides,manypartsontheproductionandprocessingofcoarseprocesstoimproveitsgeneralshapeofthesurface.Itisonlynecessaryprecisionandchooseonlythesurfacemachining.Forinstance,thread,inadditiontomechanicalprocessing,almostnootherprocessingmethodforprocessing.Anotherexampleistheblacksmithpieceskeyholeprocessing,aswellastrainingtobeconductedimmediatelyafterthemechanicalcompletionoftheprocessing.PrimaryCuttingParametersCuttingtheworkpieceandtoolbasedonthebasicrelationshipbetweenthefollowingfourelementstofullydescribe:thetoolgeometry,cuttingspeed,feedrate,depthandpenetrationofacuttingtool.CuttingToolsmustbeofasuitablematerialtomanufacture,itmustbestrong,tough,hardandwear-resistant.Toolgeometry--tothetipplaneandcutteranglecharacteristics--foreachcuttingprocessmustbecorrect.Cuttingspeedisthecuttingedgeofworkpiecesurfacerate,itisinchesperminutetoshow.Inordertoeffectivelyprocessing,andcuttingspeedmustadapttothelevelofspecificparts--withknives.Generally,themorehardworkpiecematerial,thelowertherate.ProgressiveTooltospeediscutintotheworkpiecespeed.Iftheworkpieceortoolforrotatingmovement,feedrateperroundoverthenumberofinchestothemeasurement.Whentheworkpieceortoolforreciprocatingmovementandfeedrateoneachtripthroughthemeasurementofinches.Generally,inotherconditions,feedrateandcuttingspeedisinverselyproportionalto.Depthofpenetrationofacuttingtool--toinchesdollars--isthetooltotheworkpiecedistance.Rotarycuttingittothechiporequaltothewidthofthelinearcuttingchipthickness.Roughthanfinishing,deeperpenetrationofacuttingtooldepth.WearsofCuttingToolWealreadyhavebeenprocessedandtherattleofthecountlesscracksedgetool,welearnthattoolweararebasicallythreeforms:flankwear,theformerflankwearandV-Notchwear.Flankwearoccurredinboththemainbladeoccurredviceblade.Onthemainblade,shoulderremovedbecausemostmetalchipmandate,whichresultedinanincreasecuttingforceandcuttingtemperatureincrease,Ifnotallowedtocheck,Thatcouldleadtotheworkpieceandthetoolvibrationandprovideforefficientcuttingconditionsmaynolongerexist.Vice-bladedon,itisdeterminedworkpiecedimensionsandsurfacefinish.Flankwearsizeofthepossiblefailureoftheproductandsurfacefinisharealsoinferior.Inmostactualcuttingconditions,astheprincipalintheformerfirstdeputyflankbeforeflankwear,weararrivalenough,Toolwillbeeffective,theresultsaremadeunqualifiedparts.AsToolstressonthesurfaceuneven,chipandflankbeforeslidingcontactzonebetweenstress,inslidingcontactthestartofthelargest,andincontactwiththetailofzero,soabrasivewearintheregionoccurred.Thisisbecausethecardcuttingedgethanthenearbysettlementsnearthemoreseriouswear,andbladedchipduetothevicinityoftheformerflankandlostcontactwearlighter.ThisresultsfromacertaindistancefromthecuttingedgeofthesurfaceformedbeforetheknifepointMapit,whichisusuallyconsideredbeforewear.Undernormalcircumstances,thisiswearcross-sectionalshapeofanarc.Inmanyinstancesandfortheactualcuttingconditions,theformerflankwearcomparedtoflankwearlight,Thereforeflankwearmoregenerallyasatoolfailureofscalesigns.Butbecausemanyauthorshavesaidinthecuttingspeedoftheincrease,Maetosurfacetemperaturethantheknifesurfacetemperatureshaverisenfaster.butbecauseanyformofwearrateisessentiallytemperaturechangesbythesignificantimpact.Therefore,theformerusuallywearinhigh-speedcuttinghappen.Themaintoolflankwearthetailisnotprocessedwiththeworkpiecesurfaceincontact,Thereforeflankwearthanwearalongwiththeendsmorevisible,whichisthemostcommon.Thisisbecausethelocaleffect,whichisasroughonthesurfacehashardenedlayer,Thiseffectisbycuttinginfrontofthehardeningoftheworkpiece.Notjustcutting,andasoxidationskin,thebladelocalhightemperaturewillalsocausethiseffect.Thispartialwearnormallyreferredtoaspitsexualwear,butoccasionallyitisveryserious.DespitetheemergenceofthepitsontheCuttingToolnatureisnotmeaningfulimpact,butoftenpitsgraduallybecomedarkerIfcuttingcontinuedthecase,thentherecutterfracturecrisis.Ifanyformofsexualallowedtowear,eventuallywearrateincreaseobviouslywillbeatooltodestroyfailuredestruction,thatwillnolongertoolforcutting,causetheworkpiecescrapped,itisgood,cancauseseriousdamagemachine.Forvariouscarbidecuttingtoolsandforthevarioustypesofwear,intheeventofaseriouslapse,onthetoolthathasreachedtheendofthelifecycle.Butforvarioushigh-speedsteelcuttingtoolsandwearbelongingtothenon-uniformityofwear,hasbeenfound:Whenthewearandeventoallowforaseriouslapse,themostmeaningfulisthatthetoolcanre-milluse,ofcourse,Inpractice,cuttingthetimetousethantheshorttimelapse.Severalphenomenaareonetoolseriouslapsebeganfeatures:themostcommonisthesuddenincreasecuttingforce,appearedontheworkpieceburningringpatternsandanincreaseinnoise.TheEffectofChangesinCuttingParametersonCuttingTemperaturesInmetalcuttingoperationsheatisgeneratedintheprimaryandsecondarydeformationzonesandthisresultsinacomplextemperaturedistributionthroughoutthetool,workpieceandchip.Atypicalsetofisothermsisshowninfigurewhereitcanbeseenthat,ascouldbeexpected,thereisaverylargetemperaturegradientthroughoutthewidthofthechipastheworkpiecematerialisshearedinprimarydeformationandthereisafurtherlargetemperatureinthechipadjacenttothefaceasthechipisshearedinsecondarydeformation.Thisleadstoamaximumcuttingtemperatureashortdistanceupthefacefromthecuttingedgeandasmalldistanceintothechip.Sincevirtuallyalltheworkdoneinmetalcuttingisconvertedintoheat,itcouldbeexpectedthatfactorswhichincreasethepowerconsumedperunitvolumeofmetalremovedwillincreasethecuttingtemperature.Thusanincreaseintherakeangle,allotherparametersremainingconstant,willreducethepowerperunitvolumeofmetalremovedandcuttingtemperatureswillreduce.Whenconsideringincreaseinundeformedchipthicknessandcuttingspeedthesituationismorecomples.Anincreaseinundeformedchipthicknessandcuttingspeedthesituationismorecomplex.Anincreaseinundeformedchipthicknesstendstobeascaleeffectwheretheamountsofheatwhichpasstotheworkpiece,thetoolandchipremaininfixedproportionsandthechangesincuttingtemperaturetendtobesmall.Increaseincuttingspeed,however,reducetheamountofheatwhichpassesintotheworkpieceandthisincreasethetemperatureriseofthechipinprimarydeformation.Further,thesecondarydeformationzonetendstobesmallerandthishastheeffectofincreasingthetemperaturesinthiszone.Otherchangesincuttingparametershavevirtuallynoeffectonthepowerconsumedperunitvolumeofmetalremovedandconsequentlyhavevirtuallynoeffectonthepowerconsumedperunitvolumeofmetalremovedandconsequentlyhavevirtuallynoeffectonthecuttingtemperatures.Sinceithasbeenshownthatevensmallchangesincuttingtemperaturehaveasignificanteffectontoolwearrate,itisappropriatetoindicatehowcuttingtemperaturescanbeassessedfromcuttingdata.Themostdirectandaccuratemethodformeasuringtemperaturesinhigh-speed-steelcuttingtoolsisthatofWright&Trentwhichalsoyieldsdetailedinformationontemperaturedistributionsinhigh-speed-steeltoolswhichrelatesmicrostructuralchangestothermalhistory.Trenthasdescribedmeasurementsofcuttingtemperaturesandtemperaturedistributionsforhigh-speed-steeltoolswhenmachiningawiderangeofworkpiecematerials.Thistechniquehasbeenfurtherdevelopedbyusingscanningelectronmicroscopytostudyfine-scalemicrostructuralchangessrisingfromovertemperingofthetemperedmartensiticmatrixofvarioushigh-speed-steels.Thistechniquehasalsobeenusedtostudytemperaturedistributionsinbothhigh-speed-steelsinglepointturningtoolsandtwistdrills.AutomaticFixtureDesignAssemblyequipmentusedinthetraditionalsynchronousfixtureputpartsofthefixturemobilecenter,toensurethatcomponentsfromtransmissionfromtheplaneorequipmentplateplacedafterremovalhasbeenscheduledforposition.However,incertainapplications,mobilemandatorypartsofthecenterline,itmaycausepartsorequipmentdamage.Whenpartsvulnerabilityandmayleadtoasmallvibrationabandoned,orwhentheirlocationisbymachinespindleorspecifictodie,Toleranceagainorwhentherequestisasophisticated,itwouldratherletthefixturetoadapttothelocationofparts,andnotthecontrary.Forthesetasks,Elyria,Ohio,thecompanyhasdevelopedZaytranageneralnon-functionaldatasynchronizationWestcategoryFLEXIBILITYfixture.Fixturebecauseoftheinteractionandsynchronizationdevicesisindependent,Thesynchronousdevicecanusesophisticatedequipmenttoreplacetheslipwithoutaffectingthefixtureforce.Fixturespecificationrangefrom0.2inchesitinerary,5poundsclampingforceofthesix-inchtrip,400-inchclampingforce.Thecharacteristicsofmodernproductionisbecomingsmallerandsmallerquantitiesandproductspecificationsbiggestchanges.Therefore,inthefinalstagesofproduction,assemblyofproduction,quantityandproductdesignchangesappeartobeparticularlyvulnerable.Thissituationisforcingmanycompaniestomakegreatereffortstorationalizetheextensivereformandthepreviouslymentionedcaseofassemblyautomation.Despiteflexiblefixturebehindtherapiddevelopmentofflexibletransportandhandlingdevices,suchasbackwardinthedevelopmentofindustrialrobots,itisstillexpectedtoincreasetheflexibilityfixture.Infacttheimportantfixturedevices--theproductionofthedevicestostrengtheninvestmentonthefixturesothatmoreflexibilityineconomicsupportholders.Accordingtotheirflexibilityandfixturecanbedividedinto:specialfixture,thefixturecombinations,thestandardfixture,highflexiblefixture.Flexiblefixtureondifferentpartsoftheirhighadaptabilityandthefewlow-costreplacementforthecharacteristic.Formscantransformthestructureoftheflexiblefixturecanbeinstalledwiththechangeofstructurecomponents(suchasneedlecheekplate,Multi-chipcomponentsandflakecheekplate),anon-standardworkpiecegripperorclampingelements(forexample:commencementstandardwithaclampingfixtureandmobilecomponentsfixturesupportingdocuments),orwithceramicorhardeningoftheintermediarysubstances(suchas:Mobileparticlebedfixtureandheatfixturetightfixture).Toproduction,thepartsweresecuredfixture,theneedtogenerateclampingfunction,itsfixturewithafewunrelatedtothesexualsubmissivesteps:Accordingtotheprocessingwaspartofthatfoundationandworkingcharacteristicstodeterminetheworkpiecefixtureintherequiredposition,thenneedtoselectsomestabilityflatcombination,Theseconstituteastableplanewasfixedintheworkpiecefixturesetpositionontheclamp-profilestructure,allbalancedandtorque,ithasalsoensuredthattheworkfeaturesclosetotheworkpiece.Finally,itmustbecalculatedandadjusted,assemblyordisassemblybestandardfixturecomponentsrequiredfortheposition,sothattheworkpiecefirmlybyclampingfixtureinChina.Inaccordancewiththisprocedure,theoutlinefixturestructureandequippedwiththeplanningandrecordingprocesscanbeautomatedcontrol.Structuralmodelingtaskistoproducesomestableflatcombination,Thus,theseplaneoftheworkpiecesclampingforceandwillfixturestability.Accordingtousualpractice,thistaskcanbehuman-machinedialoguethatisalmostcompletelyautomatedwaytocompletion.Aman-machinedialoguethatisautomatedfixturestructuremodelingtodeterminethemeritscanbeconductedinanorganizedandplanningfixturedesign,reducetheamountofthedesign,shorteningthestudyperiodandbetterdistributionofworkconditions.Inshort,canbesuccessfullyachievedsignificantlyimprovefixtureefficiencyandeffectiveness.Fullypreparedtostructureprogramsandthenumberofmaterialcircumstances,thecompletionofthefirstsuccessfulassemblycansaveupto60%ofthetime.Thereforefixtureprocessmodelingagenciesisthepurposeoftheprogramhaveappropriatedocuments.

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