1、MoldhighspeedmillingprocessingtechnologyTheabstractIntroducedthehighspeedmillinginthemoldprocessingapplicationaswellastheinfluence,andbriefintroductionhighspeedmillingenginebedstructure,controlsystemandcuttingtool.Hascarriedonthesimpleanalysistothehighspeedprocessingcraft.Keywordhighspeedmilling;mol
2、dprocessingFirst,forewordInthemodernmoldproduction,alongwithtomodelsartisticandthefunctionmustobtainmoreandmorehigh,modelstheinternalstructuretodesignmoreandmorecomplex,themoldcontourdesigndaybydayisalsocomplex,thefreecurvedsurfaceaccountsfortheproportiontoincreaseunceasingly,thecorrespondingmoldstr
3、ucturealsodesignsmoreandmorecomplex.Theseallsetahigherrequesttothemoldprocessingtechnology,notonlyshouldguaranteethehighmanufactureprecisionandthesurfacequality,moreovermustpursuetheprocessingsurfaceartistic.Alongwithisunceasinglythoroughtothehighspeedprocessingengineeringresearch,isprocessingtheeng
4、inebed,thenumericalcontrolsystem,thecuttingtoolsystem,CAD/especiallyCorrelationtechnologyandsoonCAMsoftwaredevelopsunceasinglyundertheimpetus,highspeedprocessesthetechnologymoreandmoremanytoapplyinthemoldcavityprocessingandthemanufacture.Thenumericalcontrolhigh-speedcuttingprocessingtookinthemoldman
5、ufactureamostimportantadvancedmanufacturetechnology,isthecollectionishighlyeffective,highquality,thelowconsumptioninabodyadvancedmanufacturetechnology.Isoppositeinthetraditionalmachining,itscuttingspeed,enteredtothespeedhadtheverybigenhancement,moreovercutthemechanismnottobesame.Thehigh-speedcutting
6、causedthemachiningtohavetheleap,itsspecificpowermetalexcisionrateenhanced30%40%,thecuttingforcereduced30%,thecuttingtoolworkingdurabilityenhanced70%,remainedhotlylargescalereducesintheworkpiececutting,thelowstepshuddervanishednearly.Alongwiththecuttingspeedenhancement,unittimesemifinishedmaterialsma
7、terialremovingrateincreased,thecuttingtimereduced,theprocessingefficiencyenhanced,thusreducedtheproductmanufacturecycle,enhancedtheproductmarketcompetitivepower.Atthesametime,thehighspeedprocessingsmallamountenteredquicklycausesthecuttingforcetoreduce,thescraphighspeeddischargedreducedtheworkpiececu
8、ttingforceandthethermalloaddistorts,enhancestherigiditytobebadandthethinwallcomponentsmachiningpossibility.Becausecuttingforcereducing,therotationalspeedenhancementcausesthecuttingsystemtheoperatingfrequencytobefarawaytheenginebedthelowstepnaturalfrequency,buttheworkpiecesurfaceroughnessismostsensit
9、ivetothelowstepfrequency,fromthisreducedthesurfaceroughness.Inmoldhighhardsteelstock(HRC45HRC65)intheprocessingprocess,usesthehigh-speedcuttingtobepossibletosubstitutefortheworkingprocedurewhichtheelectricalfinishingandrubstruncatespolishes,thushasavoidedtheelectrodemanufactureandthetime-consumingel
10、ectricalfinishing,largescalereducedfitter,spolishingwithtothrowthelightquantity.Thinwal1moldworkpiecemoreandmoreneedswhichregardingsomemarketsin,thehighspeedmillingalsomaysmoothlycomplete,moreoverinthehighspeedmillingCNCprocessingcenter,amoldattireclampsmaycompletethemultiplexstepofprocessing.Thehig
11、hspeedprocessingtechnologyhashadthehugeinfluencetothemoldprocessingcraft,changedthetraditionalmoldprocessingtousezztheannealing-*millingprocessingfheattreatment-*torubtruncates7ortheelectricsparkmachiningfmanuallypolishes,polishesandsoonthecomplexlongtechnicalprocess,evenmightusethehigh-speedcutting
12、processingsubstitutionoriginalcompleteworkingprocedure.Thehighspeedprocessingtechnologybesidesmayapplyinthehardmoldcavitydirectprocessing(inparticularhalfprecisionworkandprecisionwork),inEDMaspectandsoonelectrodeprocessing,fasttypemanufacturealsoobtainedthewidespreadapplication.Themassproductionspra
13、cticeindicatedthat,theapplicationhigh-speedcuttingtechnologymaysaveinthemoldfollowingprocessing80%handworktogrindthetimeapproximately,savestheprocessingcostexpensenearly30%,themoldfaceworkprecisionmayreach1m,thecuttingtoolcuttingefficiencymayenhanceonetime.Second,highspeedmillingprocessingenginebedT
14、hehigh-speedcuttingtechnologyisoneofmachiningtechnologymaindevelopmentdirections,italongwithfoundationtechnologytheandsoonCNCtechnology,microelectronictechnology,newmaterialandnewstructuredevelopmentbutstepsahigherstair.Becausethemoldprocessesparticularaswellashighspeedprocessingtechnologyowncharact
15、eristic,(processedenginebed,numericalcontrolsystem,cuttingtooltothemoldhighspeedprocessingrelatedtechnologyandthecraftsystemandsoon)proposedprocessedahigherrequestcomparedtothetraditionalmold.1. HighstableenginebedstrutpartThehigh-speedcuttingenginebedlathebedandsoonsupportstheparttobesupposedtohave
16、verywellmoves,thestaticrigidity,hotrigidityandbestdampingcharacteristic.Themajorityofenginebedsallusehighgrade,thehighrigidityandGaoKangzhangthegrayirontookthestrutpartmaterial,someenginebedcompaniesalsoincreasethehighdampingcharacteristicinthefoundationpolymerconcrete,byincreasesitsvibration-proofa
17、ndthethermostability,thisnotonlymayguaranteetheenginebedprecisionisstable,alsomaypreventwhencuttingthecuttingtoolinspirestrembles.Usestheenclosedlathebeddesign,theoverallcastinglathebed,thesymmetricallathebedstructureandhasthedenselycoveredstiffenerandsoonalsoenhancestheenginebedstableimportantmeasu
18、re.Someenginebedcompanies,researchanddevelopmentdepartmentsindesignprocess,butalsousesthemodalityanalysisandthefiniteelementstructurecomputationandsoon,optimizedthestructure,stablycausestheenginebedstrutparttobereliable.2. EnginebedmainaxleThehighspeedenginebedmainaxleperformanceistherealizationhigh
19、speedcuttingprocessingimportantcondition.Thehigh-speedcuttingenginebedmainaxlerotationalspeedscopeis10000100000mMin,themainaxlepowerisbiggerthan15kW.Isnotbiggerthan0.005unthroughthemainaxlecompressedairoforaxialplaybetweenthecoolingsystemcontrolhiltandthemainaxle.Alsorequeststhemainaxletohavethefas
20、tverticalspeed,toassigntheperformancewhichthepositionisfaststops(namelytohaveextremelyhighangleadditionandsubtractionspeed),thereforethehighspeedmainaxleoftenusestheliquidstaticpressurebearingtype,theairstaticpressurebearingtype,thethermo-compressionnitridingsilicon(Si3N4)theceramicbearingmagnetisma
21、erosolbearingtypeisostructuralismform.Lubricatesusestechnologyandsoonoilgaslubrication,splashlubrication.Themainaxlecoolsusesthemainaxleinteriorwatercoolinggenerallyoraircooled.3. TheenginebedactuatesthesystemInordertosatisfythemoldhighspeedprocessingtheneed,highspeedprocessestheenginebedtheactuatio
22、nsystemtobesupposedtohavethefollowingcharacteristic:(1) highenteringforspeed.Theresearchindicatedthat,regardingtheminordiametercuttingtool,enhancestherotationalspeedandeachtoothentersforthequantityisadvantageousinreducesthecuttingtoolattrition.Atpresentcommonlyusedenteringforthespeedrangeis2030mMin,
23、likeusesleadsgreatlytheballbearingguidescrewtransmission,entersmayreach60mforthespeedMin;Usesthestraightlineelectricalmachinerythenmayenabletoachieve120mtothespeedMin.(2) highacceleration.Hasthegoodaccelerationcharacteristictothethreedimensionalcomplexcurvedsurfacesilhouettehighspeedprocessingreques
24、tactuationsystem,therequestprovidesthedriverwhichthehighrapidadvanceorprogressgives(toenterspeedapproximately40mquicklyMin,the3Doutlineprocessingspeedis10mMin),canprovide0.4mS2to10mThes2accelerationandreducesthespeed.Theenginebedmanufacturermostlyusestheentireclosedlooppositionservo-controlslightlyt
25、olead,thegreatsize,thehighgradeballbearingguidescreworleadsgreatlymanyguidescrews.Alongwiththeelectricalmachinerytechnologydevelopment,theadvancedstraightlineelectricmotoralreadywaspublished,andthesuccessappliedintheCNCenginebed.TheadvancedstraightlinedirectmotordriveenabletheCNCenginebednolongertoh
26、avethemassinertia,inadvance,questionandsoonlagandvibration,speduptheservospeedofresponse,increasedtheservo-controlprecisionandtheenginebedprocessingprecision.4. NumericalcontrolsystemTheadvancednumericalcontrolsystemisguaranteedthemoldcomplexcurvedsurfacehighspeedprocessingqualityandtheefficiencykey
27、aspect,themoldhigh-speedcuttingprocessingtothenumericalcontrolsystembasicrequestis:A. Highspeednumericalcontrolreturnroute(Digitalcontrolloop),including:32orabove64bitparallelprocessorsand1.5Gbharddisk;Extremelyshortstraightlineelectricalmachinerysamplingtime.B. Speedandaccelerationfeed-forwardcontr
28、ol(Feedforwardcontrol);Digitalactuationsystemcrawlingcontrol(Jerkcontrol).C. Advancedinsertsmakesupthemethod(toinsertbasedontheNURBStransectmakesup),byobtainsthegoodsurfacequality,theprecisesizeandthehighgeometryprecision.D. Pretreatment(Look-ahead)function.Therequesthasthelargecapacitycushionregist
29、er,mayreadinadvanceandinspectsmanysegments(forexampletheDMGenginebedtobepossibletoreach500segments,theSimenssystemmayreacha10002000segment),inordertowhenisprocessedthesuperficialshape(curvature)changesmaypromptlyadoptchangesformeasureandsoonspeedbyavoidscuttingandsoon.E. Theerrorcompensatoryfunction
30、includingbecausethestraightlineelectricalmachinery,themainaxleandsoongivesoffheatthehoterrorwhichcausestocompensate,thequadrantalerrorcompensates,themeasurementsystemerrorcompensatesandsoonthefunction.Inaddition,themoldhigh-speedcuttingprocessingveryisalsohightothedatatransmissionspeedrequest.F. Th
31、etraditionaldataconnection,liketheRS232serialmouthtransmissionspeedis19.2kb,butmanyadvancedprocessingscentershaveusedtheetherlocalareanetwork(Ethernet)tocarryonthedatatransmission,thespeedmayreach200kb.5. CoolinglubricationThehighspeedprocessingusesthebeltcoatingthehardalloytools,inhighspeed,thehigh
32、temperaturesituationdoesnotneedthecuttingcompound,thecuttingefficiencytobehigher.Thisisbecause:Themillingmainaxlehighspeedrevolves,thecuttingcompoundifachievedthecuttingarea,firstmustovercometheenormouscentrifugalforce;Evenifitovercamethecentrifugalforcetoenterthecuttingarea,alsowaspossibleasaresult
33、ofthecuttingareahightemperaturebuttoevaporateimmediately,thecoolingeffectverysmal1didnotevenhave;Atthesametimethecuttingcompoundcancausethecuttingtooledgeofaswordthetemperatureintensechange,iseasytocausethecracktheproduction,thereforemustpicktheoi1used/Gascoolinglubricationdrytypecuttingway.Thiswaym
34、ayusethecompressedgasrapidlythecuttingwhichthecuttingareaproduces,thusthemassivecuttingshotlywillcarryoff,atthesametimemightformsextremelythinmicroscopicprotectivefilmaftertheatomizationlubricatingoilinthecuttingtooledgeofaswordandtheworkpiecesurface,buteffectivelywilllengthenthecuttingtoollifeanden
35、hancesthecomponentsthesurfacequality.Third,high-speedcuttingprocessingcuttingtoolThecuttingtoolisinthehigh-speedcuttingprocessingoneofmostactiveimportantfactors,itisaffectingtheprocessingefficiency,theproductioncostandtheproductprocessingprecisiondirectly.Thecuttingtoolmustwithstandloadandsoonhighte
36、mperature,highpressure,friction,impactandvibrationinthehighspeedprocessingprocess,thehigh-speedcuttingcuttingtoolshouldhavethegoodmachinecapabilityandthethermostability,namelyhasthegoodanti-impact,thewearabilityandresistsheatthewearycharacteristic.Thehigh-speedcuttingprocessingcuttingtooltechnologic
37、aldevelopmentspeedisveryquick,applicationmanylikediamonds(PCD),cubicboronnitride(CBN),ceramiccuttingtool,coatinghardalloy,(carbon)titaniumnitrideshardalloyTIC(N)andsoon.Intheprocessingcastironandinthealloysteelcuttingtool,thehardalIoyisthemostcommonlyusedcuttingtoolmaterial.HardalIoytoolsresistancet
38、oweargood,butthesolidityratiocubeboronnitrideandtheceramicsarelow.Inordertoenhancedegreeofhardnessandthesuperficiallyattractivefineness,usesthecuttingtoolcoatingtechnology,thecoatingmaterialforthetitaniumnitrides(TiN),thealuminiumnitridetitanium(TiALN)andsoon.Thecoatingtechnologycausesthecoatingbyth
39、esolecoatingdevelopmentformultilayered,themanykindsofcoatingmaterialcoating,hasbecomeoneofenhancementhigh-speedcuttingabilityessentialtechnical.Thediameterinthe1040mmscope,alsohasthecarbontitaniumnitridescoatingthehardalloybittobeabletoprocesstheLuoriverdegreeofhardnesstobesmallerthan42materials,but
40、thetitaniumnitridesaluminumcoatingcuttingtoolcanprocesstheLuoriverdegreeofhardnessis42evenhighermaterials.Whenhigh-speedcuttingsteelproducts,thecuttingtoolmaterialshouldselectthehotrigidityandthefatiguestrengthhighPkindofhardalloy,thecoatinghardalloy,thecubicboronnitride(CBN)andtheCBNcompoundcutting
41、toolmaterial(WBN)andsoon.Thecuttingcastiron,shouldselectthefinegrainKkindofhardalloytocarryontheroughmachining,selectsthecompoundnitridedsiliconceramicsorthecrystalcombinationcubeboronnitride(PCNB)thecompoundcuttingtoolcarriesontheprecisionwork.Whenpreciseprocessingnon-ferrousmetalornonmetalliemater
42、ial,shouldselectcrystalcombinationdiamondPCDortheCVDdiamondcoatingcuttingtool.Whenchoicecuttingparameter,inviewofthecircularshearbladeandaballmillingcutter,shouldpayattentiontotheeffectivediametertheconcept.Thehighspeedmillingcuttingtoolshouldpressthebalancedesignmanufacture.Thecuttingtoolfrontangle
43、mustbesmallerthantheconventionalcuttingtoolfrontangle,theclearanceangleisslightlybig.Thehostvice-cuttingedgeattachmentpointshouldthecavettoortheleadangle,increasesthevertexangle,preventstheknifepointplacehotattrition.Shouldenlargenearbytheknifepointthecuttingedgelengthandthecuttingtoolmaterialvolume
44、enhancesthecuttingtoolrigidity.Issafeintheguaranteeandsatisfiestheprocessingrequestunderthecondition,thecuttingtoolhangsextendsasfaraspossibleshort,cutterbodycentraltoughnessisfriendswith.Thehiltmustbesturdierthanthecuttingtooldiameter,connectsthehandletoassumebutactuallythepyramidal,byincreausesin
45、thefinemillcomplexcurvedsurface.Fourth,moldhighspeedprocessingcraftThehighspeedprocessingincludingtakeremovestheremainderasthegoalroughmachining,theresidualroughmachining,aswellastakegainsthehighgradeprocessingsurfaceandtheslightstructureasthegoalhalfprecisionwork,theprecisionworkandthemirrorsurface
46、processingandsoon.1. RoughmachiningThemoldroughmachiningessentialtargetispursuesintheunittimematerialremovingrate,andishalfprecisionworkpreparationworkpiecegeometryoutline.Inthehighspeedprocessingroughmachiningshouldadoptthecraftplanisthehighcuttingspeed,GaoJingivingrateandthesmallcuttingspecificati
47、onscombination.ThecontourprocessingwayisoneprocessingwaywhichthemultitudinousCAMsoftwareusesgenerally.UsingisspiralcontourandsoontheZaxiscontourtwowayswhicharemany,alsoisinprocessestheregiononlytimetofeed,indoesnotlifttheknifeinthesituationtoproducecontinuouslythesmoothcuttingtoolway,enters,drawsbac
48、ktheknifewaytousethecirculararctocutinto,tocut.Thespiralcontourwaycharacteristicis,hasnotwaitedthehighlevelbetweenthekniferoadmigration,mayavoidfrequentlyliftingtheknife,feedingtothecomponentssurfacequalityinfluenceandmechanicaldevicenonessentialconsuming.Toissteepandtheflatsiteprocessesseparately,t
49、hecomputationsuitscontourandsuitstheusesimilar3Dbiastheregion,andmayusethespiralway,inverylittleliftsthecuttingtoolwaywhichtheknifeinthesituationproducesoptimizes,obtainsthebettersurfacequality.Inthehighspeedprocessing,certainlymustadoptthecirculararctocutinto,tocuttheconnectionway,aswellasthecirculararctransition,avoidschangingthecuttingtooltoentersuddenlyforthedirection,theprohibitionusedirectunderknifeconnectionway,avoidsburyingthecuttingtooltheworkpiece.Whenprocessesthemoldcavity,shouldavoidthecutting
