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半闭环数控车床总体设计【含3张CAD图纸】,含3张CAD图纸,闭环,数控车床,总体,设计,CAD,图纸
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英文原文CNC machine toolsWhilethespecificintentionandapplicationforCNCmachinesvaryfromonemachinetype toanother,allformsofCNChavecommonbenefits.Herearebutafewofthemoreimportant benefitsofferedbyCNCequipment.ThefirstbenefitofferedbyallformsofCNCmachinetoolsisimprovedautomation. The operatorinterventionrelatedtoproducingworkpiecescanbereducedoreliminated.ManyCNCmachinescanrununattendedduringtheirentiremachiningcycle,freeingtheoperatortodoother tasks.ThisgivestheCNCuserseveralsidebenefitsincludingreducedoperatorfatigue,fewer mistakescausedbyhumanerror,andconsistentandpredictablemachiningtimeforeach workpiece.Sincethemachinewillberunningunderprogramcontrol,theskilllevelrequiredof theCNCoperator(relatedtobasicmachiningpractice)isalsoreducedascomparedtoamachinistproducingworkpieceswithconventionalmachinetools.ThesecondmajorbenefitofCNCtechnologyisconsistentandaccurateworkpieces.TodaysCNCmachinesboastalmostunbelievableaccuracyandrepeatabilityspecifications.Thismeans thatonceaprogramisverified,two,ten,oronethousandidenticalworkpiecescanbeeasily producedwithprecisionandconsistency.AthirdbenefitofferedbymostformsofCNCmachinetoolsisflexibility.Sincethese machinesarerunfromprograms,runningadifferentworkpieceisalmostaseasyasloadinga differentprogram.Onceaprogramhasbeenverifiedandexecutedforoneproductionrun,itcan beeasilyrecalledthenexttimetheworkpieceistoberun.Thisleadstoyetanotherbenefit,fast changeover.Sincethesemachinesareveryeasytosetupandrun,andsinceprogramscanbe easilyloaded,theyallowveryshortsetuptime.Thisisimperativewithtodaysjust-in-time(JIT) product requirements.Motioncontrol-theheartofCNCThemostbasicfunctionofanyCNCmachineisautomatic,precise,andconsistentmotion control.Ratherthanapplyingcompletelymechanicaldevicestocausemotionasisrequiredon mostconventionalmachinetools,CNCmachinesallowmotioncontrolinarevolutionarymanner2.AllformsofCNCequipmenthavetwoormoredirectionsofmotion,calledaxes.Theseaxes canbepreciselyandautomaticallypositionedalongtheirlengthsoftravel.Thetwomostcommonaxistypesarelinear(drivenalongastraightpath)androtary(drivenalongacircularpath).Insteadofcausingmotionbyturningcranksandhandwheelsasisrequiredonconventionalmachinetools,CNCmachinesallowmotionstobecommandedthroughprogrammedcommands.Generallyspeaking,themotiontype(rapid,linear,andcircular),theaxestomove,theamountofmotionandthemotionrate(feedrate)areprogrammablewithalmostallCNCmachinetools.ACNCcommandexecutedwithinthecontroltellsthedrivemotortorotateaprecisenumberoftimes.Therotationofthedrivemotorinturnrotatestheballscrew.Andtheballscrewdrives thelinearaxis(slide).Afeedbackdevice(linearscale)ontheslideallowsthecontroltoconfirm thatthecommandednumberofrotationshastakenplace3. Thougharathercrudeanalogy,thesamebasiclinearmotioncanbefoundonacommontablevise.Asyourotatethevisecrank,yourotatealeadscrewthat,inturn,drivesthemovablejawonthevise.Bycomparison,alinearaxisonaCNCmachinetoolisextremelyprecise.Thenumberofrevolutionsoftheaxisdrivemotorpreciselycontrolstheamountoflinearmotionalongtheaxis.Howaxismotioniscommanded-understandingcoordinatesystems.ItwouldbeinfeasiblefortheCNCusertocauseaxismotionbytryingtotelleachaxisdrivemotorhowmanytimestorotateinordertocommandagivenlinearmotionamount4.(Thiswouldbelikehavingtofigureouthowmanyturnsofthehandleonatablevisewillcausethemovable jawtomoveexactlyoneinch!)Instead,allCNCcontrolsallowaxismotiontobecommandedinamuchsimplerandmorelogicalwaybyutilizingsomeformofcoordinatesystem.Thetwomost popularcoordinatesystemsusedwithCNCmachinesaretherectangularcoordinatesystemand thepolarcoordinatesystem.Byfar,themorepopularofthesetwoistherectangularcoordinate system.TheprogramzeropointestablishesthepointofreferenceformotioncommandsinaCNC program.Thisallowstheprogrammertospecifymovementsfromacommonlocation.Ifprogramzeroischosenwisely,usuallycoordinatesneededfortheprogramcanbetakendirectlyfromtheprint.Withthistechnique,iftheprogrammerwishesthetooltobesenttoapositiononeinchtotherightoftheprogramzeropoint,X1.0iscommanded.Iftheprogrammerwishesthetooltomovetoapositiononeinchabovetheprogramzeropoint,Y1.0iscommanded.Thecontrolwill automaticallydeterminehowmanytimestorotateeachaxisdrivemotorandballscrewtomake theaxisreachthecommandeddestinationpoint.Thisletstheprogrammercommandaxismotioninaverylogicalmanner.Alldiscussionstothispointassumethattheabsolutemodeofprogrammingisused.ThemostcommonCNCwordusedtodesignatetheabsolutemodeisG90.Intheabsolutemode,theendpointsforallmotionswillbespecifiedfromtheprogramzeropoint.Forbeginners,thisisusuallythebestandeasiestmethodofspecifyingendpointsformotioncommands.However,thereisanotherwayofspecifyingendpointsforaxismotion.Intheincrementalmode(commonlyspecifiedbyG91),endpointsformotionsarespecifiedfromthetoolscurrentposition,notfromprogramzero.Withthismethodofcommandingmotion,theprogrammermustalwaysbeaskingHowfarshouldImovethetool?Whiletherearetimeswhentheincrementalmodecanbeveryhelpful,generallyspeaking,thisisthemorecumbersomeanddifficultmethodofspecifyingmotionandbeginnersshouldconcentrateonusingtheabsolutemode.Becarefulwhenmakingmotioncommands.Beginnershavethetendencytothinkincrementally.Ifworkingintheabsolutemode(asbeginnersshould),theprogrammershouldalwaysbeaskingTowhatpositionshouldthetoolbemoved?Thispositionisrelativetoprogramzero,NOTfromthetoolscurrentposition.Asidefrommakingitveryeasytodeterminethecurrentpositionforanycommand,anotherbenefitofworkingintheabsolutemodehastodowithmistakesmadeduringmotioncommands.Intheabsolutemode,ifamotionmistakeismadeinonecommandoftheprogram,onlyonemovementwillbeincorrect.Ontheotherhand,ifamistakeismadeduringincrementalmovements,allmotionsfromthepointofthemistakewillalsobeincorrect.AssigningprogramzeroKeepinmindthattheCNCcontrolmustbetoldthelocationoftheprogramzeropointbyonemeansoranother.HowthisisdonevariesdramaticallyfromoneCNCmachineandcontroltoanother8.One(older)methodistoassignprogramzerointheprogram.Withthismethod,theprogrammertellsthecontrolhowfaritisfromtheprogramzeropointtothestartingpositionofthemachine.ThisiscommonlydonewithaG92(orG50)commandatleastatthebeginningoftheprogramandpossiblyatthebeginningofeachtool.Another,newerandbetterwaytoassignprogramzeroisthroughsomeformofoffset.Refertofig.4.Commonlymachiningcentercontrolmanufacturerscalloffsetsusedtoassignprogramzerofixtureoffsets.Turningcentermanufacturerscommonlycalloffsetsusedtoassignprogramzeroforeachtoolgeometryoffsets.Aflexiblemanufacturingcell(FMC)canbeconsideredasaflexiblemanufacturingsubsystem.ThefollowingdifferencesexistbetweentheFMCandtheFMS:1. AnFMCisnotunderthedirectcontrolofthecentralcomputer.Instead,instructionsfromthecentralcomputerarepassedtothecellcontroller.2. Thecellislimitedinthenumberofpartfamiliesitcanmanufacture.ThefollowingelementsarenormallyfoundinanFMC:CellcontrollerProgrammablelogiccontroller(PLC)MorethanonemachinetoolAmaterialshandlingdevice(robotorpallet)TheFMCexecutesfixedmachiningoperationswithpartsflowingsequentiallybetweenoperations.HighspeedmachiningThetermHighSpeedMachining(HSM)commonlyreferstoendmillingathighrotationalspeedsandhighsurfacefeeds.Forinstance,theroutingofpocketsinaluminumairframesectionswithaveryhighmaterialremovalrate1.Overthepast60years,HSMhasbeenappliedtoawiderangeofmetallicandnon-metallicworkpiecematerials,includingtheproductionofcomponentswithspecificsurfacetopographyrequirementsandmachiningofmaterialswithhardnessof50HRCandabove.Withmoststeelcomponentshardenedtoapproximately32-42HRC,machiningoptionscurrentlyinclude:Roughmachiningandsemi-finishingofthematerialinitssoft(annealed)conditionheattreatmenttoachievethefinalrequiredhardness=63HRCmachiningofelectrodesandElectricalDischargeMachining(EDM)ofspecificpartsofdiesandmoulds(specificallysmallradiianddeepcavitieswithlimitedaccessibilityformetalcuttingtools)finishingandsuper-finishingofcylindrical/flat/cavitysurfaceswithappropriatecementedcarbide,cermet,solidcarbide,mixedceramicorpolycrystallinecubicboronnitride(PCBN)Formanycomponents,theproductionprocessinvolvesacombinationoftheseoptionsandinthecaseofdiesandmouldsitalsoincludestimeconsuminghandfinishing.Consequently,productioncostscanbehighandleadtimesexcessive.Itistypicalinthedieandmouldindustrytoproduceoneorjustafewtoolsofthesamedesign.Theprocessinvolvesconstantchangestothedesign,andbecauseofthesechangesthereisalsoacorrespondingneedformeasuringandreverseengineering.Themaincriteriaisthequalitylevelofthedieormouldregardingdimensional,geometricandsurfaceaccuracy.Ifthequalitylevelaftermachiningispoorandifitcannotmeettherequirements,therewillbeavaryingneedofmanualfinishingwork.Thisworkproducessatisfactorysurfaceaccuracy,butitalwayshasanegativeimpactonthedimensionalandgeometricaccuracy.Oneofthemainaimsforthedieandmouldindustryhasbeen,andstillis,toreduceoreliminatetheneedformanualpolishingandthusimprovethequalityandshortentheproductioncostsandleadtimes.MaineconomicalandtechnicalfactorsforthedevelopmentofHSMSurvivalTheeverincreasingcompetitioninthemarketplaceiscontinuallysettingnewstandards.Thedemandsontimeandcostefficiencyisgettinghigherandhigher.Thishasforcedthedevelopmentofnewprocessesandproductiontechniquestotakeplace.HSM provideshopeandsolutions.MaterialsThedevelopmentofnew,moredifficulttomachinematerialshasunderlinedthenecessitytofindnewmachiningsolutions.Theaerospaceindustryhasitsheatresistantandstainlesssteelalloys.Theautomotiveindustryhasdifferentbimetalcompositions,CompactGraphiteIronandaneverincreasingvolumeofaluminum3.Thedieandmouldindustrymainlyhastofacetheproblemofmachininghighhardenedtoolsteels,fromroughingtofinishing.QualityThedemandforhighercomponentorproductqualityistheresultofeverincreasingcompetition.HSM,ifappliedcorrectly,offersanumberofsolutionsinthisarea.Substitutionofmanualfinishingisoneexample,whichisespeciallyimportantondiesandmouldsorcomponentswithacomplex3Dgeometry.ProcessesThedemandsonshorterthroughputtimesviafewersetupsandsimplifiedflows(logistics)caninmostcases,besolvedbyHSM.Atypicaltargetwithinthedieandmouldindustryistocompletelymachinefullyhardenedsmallsizedtoolsinonesetup.CostlyandtimeconsumingEDMprocessescanalsobereducedoreliminatedwithHSM.Design&developmentOneofthemaintoolsintodayscompetitionistosellproductsonthevalueofnovelty.Theaverageproductlifecycleoncarstodayis4years,computersandaccessories1.5years,handphones3months.OneoftheprerequisitesofthisdevelopmentoffastdesignchangesandrapidproductdevelopmenttimeistheHSMtechnique.ComplexproductsThereisanincreaseofmulti-functionalsurfacesoncomponents,suchasnewdesignofturbinebladesgivingnewandoptimizedfunctionsandfeatures.Earlierdesignsallowedpolishingbyhandorwithrobots(manipulators).Turbinebladeswithnew,moresophisticateddesignshavetobefinishedviamachiningandpreferablybyHSM.Therearealsomoreandmoreexamplesofthinwalledworkpiecesthathavetobemachined(medicalequipment,electronics,productsfordefence,computerparts)ProductionequipmentThestrongdevelopmentofcuttingmaterials,holdingtools,machinetools,control sandespeciallyCAD/CAMfeaturesandequipment,hasopenedpossibilitiesthatmustbemetwithnewproductionmethodsandtechniques5.DefinitionofHSMSalomonstheory,Machiningwithhighcuttingspeeds.onwhich,in1931,tookoutaGermanpatent,assumesthatatacertaincuttingspeed(5-10timeshigherthaninconventionalmachining),thechipremovaltemperatureatthecuttingedgewillstarttodecrease.Giventheconclusion:.seemstogiveachancetoimproveproductivityinmachiningwithconventionaltoolsathighcuttingspeeds.Modernresearch,unfortunately,hasnotbeenabletoverifythistheorytotally.Thereisarelativedecreaseofthetemperatureatthecuttingedgethatstartsatcertaincuttingspeedsfordifferentmaterials.Thedecreaseissmallforsteelandcastiron.Butlargerforaluminumandothernon-ferrousmetals.ThedefinitionofHSMmustbebasedonotherfactors.Giventodaystechnology,highspeedisgenerallyacceptedtomeansurfacespeedsbetween1and10kilometersperminuteorroughly3300to33000feetperminute.Speedsabove10km/minareintheultra-highspeedcategory,andarelargelytherealmofexperimentalmetalcutting.Obviously,thespindlerotationsrequiredtoachievethesesurfacecuttingspeedsaredirectlyrelatedtothediameterofthetoolsbeingused.Onetrendwhichisveryevidenttodayistheuseofverylargecutterdiametersfortheseapplications-andthishasimportantimplicationsfortooldesign.Therearemanyopinions,manymythsandmanydifferentwaystodefineHSM.MaintenanceandtroubleshootingMaintenanceforahorizontalMCThefollowingisalistofrequiredregularmaintenanceforaHorizontalMachiningCenterasshowninfig.5.Listedarethefrequencyofservice,capacities,andtypeoffluidsrequired.Theserequiredspecificationsmustbefollowedinordertokeepyourmachineingoodworkingorderandprotectyourwarranty.DailyTopoffcoolantleveleveryeighthourshift(especiallyduringheavyTSCusage).Checkwaylubelubricationtanklevel.Cleanchipsfromwaycoversandbottompan.Cleanchipsfromtoolchanger.Wipespindletaperwithacleanclothragandapplylightoil.WeeklyCheckforproperoperationofautodrainonfilterregulator.OnmachineswiththeTSCoption,cleanthechipbasketonthecoolanttank.Removethetankcoverandremoveanysedimentinsidethetank.BecarefultodisconnectthecoolantpumpfromthecontrollerandPOWEROFFthecontrolbeforeworkingonthecoolanttank.DothismonthlyformachineswithouttheTSCoption.Checkairgauge/regulatorfor85psi.FormachineswiththeTSCoption,placeadabofgreaseontheV-flangeoftools.DothismonthlyformachineswithouttheTSCoption.Cleanexteriorsurfaceswithmildcleaner.DONOTusesolvents.Checkthehydrauliccounterbalancepressureaccordingtothemachinesspecifications.Placeadabofgreaseontheoutsideedgeofthefingersofthetoolchangerandrunthroughalltools.MonthlyCheckoillevelingearbox.Addoiluntiloilbeginsdrippingfromoverflowtubeatbottomofsumptank.Cleanpadsonbottomofpallets.CleanthelocatingpadsontheA-axisandtheloadstation.Thisrequiresremovingthepallet.Inspectwaycoversforproperoperationandlubricatewithlightoil,ifnecessary.SixmonthsReplacecoolantandthoroughlycleanthecoolanttank.Checkallhosesandlubricationlinesforcracking.AnnuallyReplacethegearboxoil.Draintheoilfromthegearbox,andslowlyrefillitwith2quartsofMobilDTE25oil.Checkoilfilterandcleanoutresidueatbottomforthelubricationchart.Replaceairfilteroncontrolboxevery2years.Mineralcuttingoilswilldamagerubberbasedcomponentsthroughoutthemachine.TroubleshootingThissectionisintendedforuseindeterminingthesolutiontoaknownproblem.SolutionsgivenareintendedtogivetheindividualservicingtheCNCapatterntofollowin,first,determiningtheproblemssourceand,second,solvingtheproblem.UsecommonsenseManyproblemsareeasilyovercomebycorrectlyevaluatingthesituation.Allmachineoperationsarecomposedofaprogram,tools,andtooling.Youmustlookatallthreebeforeblamingoneasthefaultarea.Ifaboredholeischatteringbecauseofanoverextendedboringbar,dontexpectthemachinetocorrectthefault.Dontsuspectmachineaccuracyifthevisebendsthepart.Dontclaimholemis-positioningifyoudontfirstcenter-drillthehole.FindtheproblemfirstManymechanicstearintothingsbeforetheyunderstandtheproblem,hopingthatitwillappearastheygo.Weknowthisfromthefactthatmorethanhalfofallwarrantyreturnedpartsareingoodworkingorder.Ifthespindledoesntturn,rememberthatthespindleisconnectedtothegearbox,whichisconnectedtothespindlemotor,whichisdrivenbythespindledrive,whichisconnectedtotheI/OBOARD,whichisdrivenbytheMOCON,whichisdrivenbytheprocessor.Themoralhereisdontreplacethespindledriveifthebeltisbroken.Findtheproblemfirst;dontjustreplacetheeasiestparttogetto.DontinkerwiththemachineTherearehundredsofparameters,wires,switches,etc.,thatyoucanchangeinthismachine.Dontstartrandomlychangingpartsandparameters.Remember,thereisagoodchancethatifyouchangesomething,youwillincorrectlyinstallitorbreaksomethingelseintheprocess6.Considerforamomentchangingtheprocessorsboard.First,youhavetodownloadallparameters,removeadozenconnectors,replacetheboard,reconnectandreload,andifyoumakeonemistakeorbendonetinypinitWONTWORK.Youalwaysneedtoconsidertheriskofaccidentallydamagingthemachineanytimeyouworkonit.Itischeapinsurancetodouble-checkasuspectpartbeforephysicallychangingit.Thelessworkyoudoonthemachinethebetter. 中文译文数控机床 虽然各种数控机床的功能和应用各不相同，但它们有着共同的优点。这里是数控设备提供的比较重要的几个优点。 各种数控机床的第一个优点是自动化程度提高了。零件制造过程中的人为干预减少或者免除了。整个加工循环中，很多数控机床处于无人照看状态，这使操作员被解放出来，可以干别的工作。数控机床用户得到的几个额外好处是：数控机床减小了操作员的疲劳程度，减少了人为误差，工件加工时间一致而且可预测。由于机床在程序的控制下运行，与操作普通机床的机械师要求的技能水平相比，对数控操作员的技能水平要求（与基本加工实践相关）也降低了。 数控技术的第二个优点是工件的一致性好，加工精度高。现在的数控机床宣称的精度以及重复定位精度几乎令人难以置信。这意味着，一旦程序被验证是正确的，可以很容易地加工出2个、10个或1000个相同的零件，而且它们的精度高，一致性好。大多数数控机床的第三个优点是柔性强。由于这些机床在程序的控制下工作，加工不同的工件易如在数控系统中装载一个不同的程序而己。一旦程序验证正确，并且运行一次，下次加工工件的时候，可以很方便地重新调用程序。这又带来另一个好处可以快速切换不同工件的加工。由于这些机床很容易调整并运行，也由于很容易装载加工程序，因此机床的调试时间很短。这是当今准时生产制造模式所要求的。 任何数控机床最基本的功能是具有自动、精确、一致的运动控制。大多数普通机床完全运用机械装置实现其所需的运动，而数控机床是以一种全新的方式控制机床的运动。各种数控设备有两个或多个运动方向，称为轴。这些轴沿着其长度方向精确、自动定位。最常用的两类轴是直线轴（沿直线轨迹）和旋转轴（沿圆形轨迹）。普通机床需通过旋转摇柄和手轮产生运动，而数控机床通过编程指令产生运动。通常，几乎所有的数控机床的运动类型（快速定位、直线插补和圆弧插补）、移动轴、移动距离以及移动速度（进给速度）都是可编程的。 数控系统中的CNC指令命令驱动电机旋转某一精确的转数，驱动电机的旋转随即使滚珠丝杠旋转，滚珠丝杠将旋转运动转换成直线轴（滑台）运动。滑台上的反馈装置（直线光栅尺）使数控系统确认指令转数已完成。 普通的台虎钳上有着同样的基本直线运动，尽管这是相当原始的类比。旋转虎钳摇柄就是旋转丝杠，丝杠带动虎钳钳口移动。与台虎钳相比，数控机床的直线轴是非常精确的，轴的驱动电机的转数精确控制直线轴的移动距离。轴运动命令的方式-理解坐标 对CNC用户来说，为了达到给定的直线移动量而指令各轴驱动电机旋转多少转，从而使坐标轴运动，这种方法是不可行的。（这就好像为了使钳口准确移动1英寸需要计算出台虎钳摇柄的转数！）事实上，所有的数控系统都能通过采用坐标系的形式以一种较为简单而且合理的方式来指令轴的运动。数控机床上使用最广泛的两种坐标系是直角坐标系和极坐标系。目前用得较多的是直角坐标系。编程零点建立数控程序中运动命令的参考点。这使得操作员能从一个公共点开始指定轴运动。如果编程零点选择恰当，程序所需坐标通常可从图纸上直接获得。如果编程员希望刀具移动到编程零点右方1英寸（25.4毫米）的位置，则用这种方法指令X1.0即可。如果编程员希望刀具移动到编程零点上方1英寸的位置，则指令Y1.0。数控系统会自动确定（计算）各轴驱动电机和滚珠丝杠要转动多少转，使坐标轴到达指令的目标位置。这使编程员以非常合理的方式命令轴的运动。理解绝对和相对运动至此，所有的讨论都假设采用的是绝对编程方式。用于指定绝对方式的最常用的数控代码是G90。绝对方式下，所有运动终点的指定都是以编程零点为起点。对初学者来说，这通常是最好也是最容易的指定轴运动终点的方法，但还有另外一种指定轴运动终点的方法。增量方式（通常用G91指定）下，运动终点的指定是以刀具的当前位置为起点，而不是编程零点。用这种方法指定轴运动，编程员往往会问“我该将刀具移动多远的距离？”，尽管增量方式多数时候很有用，但一般说来，这种方法指定轴运动较麻烦、困难，初学者应该重点使用绝对方式。指令轴运动时一定要小心。初学者往往以增量方式思考问题。如果工作在绝对方式（初学者应该如此），编程员应始终在问“刀具应该移动到什么位置？”，这个位置是相对于编程零点这个固定位置而言，而不是相对于刀具当前位置。绝对工作方式很容易确定指令当前位置，除此之外，它的另外一个好处涉及轴运动中的错误。绝对方式下，如果程序的一个轴运动指令出错，则只有一个运动是不正确的。而另一方面，如果在增量运动过程中出错，则从出错的那一点起，所有的运动都是不正确的指定编程零点记住必须以某种方式对数控系统指定编程零点的位置。指定编程零点的方式随数控机床和数控系统的不同而很不相同。（较老的）一种方法是在程序中指定编程零点。用这种方法，编程员告诉数控系统从编程零点到机床起始点的距离。通常用G92（或G50)在程序的一开始指定，很可能在各把刀具的开头指定编程零点。另一种较新、更好的指定编程零点的方法是通过偏置的形式，见图4。通常，加工中心上用于指定编程零点的偏置被称作夹具偏置，车削中心上用于指定编程零点的偏置被称作刀具几何偏置。柔性制造单元柔性制造单元（FMC）被认为是柔性制造子系统。以下是FMC和FMS之间的区别：1.FMC不受中央计算机的直接控制，中央计算机发出的指令被传送到单元控制器。2.FMC能制造的零件族的数目有限。FMC一般由下列部分组成：单元控制器可编程逻辑控制器（PLC）一台以上的机床物流设备（机器人或托盘）FMC按顺序对零件流执行固定的加工操作。高速加工术语“高速加工(HSM)”一般是指在高转速和大进给量下的立铣。例如，以很高的金属切除率对铝合金飞机翼架的凹处进行切削。在过去的60年中，高速加工己经广泛应用于金属与非金属材料，包括有特定表面形状要求的零件生产和硬度高于或等于HRC50的材料切削。对于大部分淬火到约为HRC32-42的钢零件，当前的切削选项包括：在软（退火）工况下材料的粗加工和半精加工达到最终硬度要求为HRC63的热处理模具行业的某些零件的电极加工和放电加工(EDM)（特别是金属切削刀具难以加工的小半径圆弧和深凹穴）用适合的硬质合金、金属陶瓷、整体硬质合金、混合陶瓷或多晶立方氮化硼（PCBN）刀具进行的圆柱平面凹穴表面的精加工和超精加工。对于许多零件，生产过程牵涉到这些选项的组合，在模具制造案例中，它还包括费时的精加工，结果导致生产成本高和准备时间长。在模具制造业中典型的是仅生产一个或几个同一产品。生产过程中产品的设计不断改变，由于产品改变，模具制造中需要测量与反求工程。加工的主要标准是模具的尺寸和表面粗糙度方面的质量水平。如果加工后的质量水平低，不能满足要求，就需手工精加工。手工精加工可产生令人满意的表面粗糙度，但是对尺寸和几何精度总是产生不好的影响。模具制造业的主要目标之一，一直是并且仍然是减少或免除手工抛光，从而提高质量、降低生产成本和缩短准备时间。高速加工发展的主要经济和技术因素生存日益激烈的市场竞争导致不断设立新的标准，对时间和成本效率的要求越来越高，这就迫使新工艺和生产技术不断发展。高速加工提供了希望和解决方案材料新型难加工材料的开发迫切需要寻找新的切削解决方案。航空航天业使用耐热合金钢和不锈钢，汽车工业使用了不同的双金属材料、小石墨铸铁，并增加了铝的用量。模具制造业必须面对切削高硬度的淬火钢
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