文献翻译模具型腔数控加工计算机辅助刀具选择和研究.docx
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文献翻译模具型腔数控加工计算机辅助刀具选择和研究
Mouldtypeofnumericalcontrolprocesscomputerassistthecutterchooseandstudy
Foreword
Numericalcontrolincludecutterproductionandcutteroforbitchoosetwokeyproblemsprocess,.Thefirstproblemhasbeengotandstudiedextensivlyanddeeplyoverthepast20years,alotofalgorithmsdevelopedhavealreadygotapplicationincommercialCAD/CAMsystem.MostCAMsystemscanproducethecutterorbitautomaticallyafterusersinputrelevantparametersatpresent.Comparativelyspeaking,itisstillnotripetoregardquality,efficiencyastheresearchofchoosingtheproblemofcutterofoptimizingthegoalcorrectly,donothavecommercialCAMsystemthatcanofferthepreferreddecisionsupporttoolofcutteratpresent,thereforeitisdifficulttorealizetheintegratingautomaticallyandorganicallyofCAD/CAM..Thecutterischosentousuallyincludecuttertypeandcuttersize.Generallyspeaking,suitableforoneprocessingcutteroftargetformuchkind,onecuttercanfinishdifferentprocessingtasks,soitiseasiertoonlyconsidermeetingthecutterthatbasicallyprocessestherequirementandchoose,especiallytogeometirccharacteristicsofmodelsuchasthehole,trough,etc..Butinfact,itiscommonforcuttertochooseandsureoptimizationgoalinterrelate,forinstancemostheavytocutefficiency,processtime,minimumprocesscost,longestservicelife,etc.atleast,sothecutterischosenitisacomplicatedoptimizationquestion.Suchasmouldtypeoneofparts,becausethegeometircformiscomplicated(usuallyincludecurvedsurfaceoffreedomandisland),influencegeometrythatcutterchooseitrestrainsfromtobecanexplicittosayamongCADmodel,needtodesignthecorrespondingalgorithmtodraw,thereforechoosethecutterspecificationsuitableandcutterassociation,itisnoteasythingsbyimprovingefficiencyandqualityprocessedinnumericalcontrol.
Mouldtypegenerallywithpreparationmethodthatnumericalcontrolmill,usuallyincludingroughmachining,halffinishmachining,preciseprocessofprocessingetc..Theprincipleofroughmachiningistosparenoefforttoremovethesurplusmetalwithhighefficiency,thereforehopetochoosethelargercutter,butthecutterisoversized,maycausetheincreaseofthecrudevolume;Halffinishmachiningoftaskstoremoveroughmachiningleaveoverstepthatgetoffmainly;Finishmachiningmainlyguaranteessizeofthepartandsurfacequality.Consider,goon,selectexist,surebycomputerdifficultautomaticallytotallyuptillnow,thereforeassistthecuttertochooseinthecomputerthatwedeveloped(ComputerAidedToolSelection,CATS)amongthesystem,baseon,provideoneaiddecisiontoolforuser,roughmachining,halffinishmachining,precisetoprocessetc.,therealpolicy-makingpowerisstilllefttousers,inordertogivefullplaytotheadvantagesofcomputerandpeople.
1Basicstructureofthesystem
CATSsystemisCADmodel,outputforcuttertype,cutterspecification,milldepthofsharpening,enterthegivingamount,rotationalspeedofmainshaft(cutthepace)andprocesssixparameterssuchastime(suchasFig.1),includingchoosingtheaiddecisiontoolincuttertype,roughmachiningcutterchooseaiddecisiontool,halffinishmachiningcutterchooseaiddecisiontoolandfinishmachiningcutterchooseaiddecisiontool,etc.
GiventheroughmachininginXingqiangprocessingoftheimportantposition(usuallyrelytime5~10times),roughmachining,thesystemautomaticallyoptimizeportfoliowithcutleryfunctionstoenhanceoverallprocessingefficiency.Inadditiontothedecision-makingtools,thesystemalsohasadetailedlookcutlerynorms,basedonthetypeandsizecutleryrecommendedprocessingparametersandassessthefunctionofprocessingtime,thelastgenerationoftheoverallresultsofchoicecutlerystatements(figure2).Allthedataandknowledgesystemscutlerydonebythebackgrounddatabasesupport.
2Keytechnologiesandalgorithms
2.1Cutlerytypechoice
AccordingtoAssistantXingqiangdigitalprocessingpractice,XingqiangXistategeneralprocessingcutleryintomillingcutter,millingcutterradiusmillingcutterandthefirstthreeballs.Dbasedcutlerydiameter,radiusradiusrwhenr=0formillingcutter,0Cutlerycanbedividedintotheoverallstyleandembedfilmsceremony.Forinlayfilmstyle,thekeyistoselectthematerialsrazorblades,razorbladesmaterialschoicedependsonthreeelements:
theprocessingofworkingmaterials,machinetoolsandcutleryjigstabilityofthestatestructures.Processingsystemwillbetranslatedintomaterialsteel,stainlesssteel,castiron,nonferrousmetals,materialsandhardtocutmaterialssixgroups.Machinetooljigstabilityintogood,betterandlessthanthreelevels.Cutleryinvestigationintotheshortandlongcantileverstructurestwo,thesystemautomaticallyreasoningonthebasisofthespecificcircumstancesofrazorbladesmaterials,decision-makingknowledgefromWaltercutlerymanualsystembytheusersfirstchoicecutlerytypeintheworld.Toembedfilmstylecutlery,arules-basedautomatedreasoningsuitablerazorbladesmaterials.Forexample,ifthefinalprocessingofmaterialsforthe"steel",machinetooljigforgoodstability,cutlerycantileverstructuresforshort,razorbladesmaterialsforWAP25.
Roughmachiningcutleryportfoliooptimization
Xingqiangroughmachiningtheaimistomaximizetheremovalofexcessmetalnormallyusedmillingcutter,take-cuttingapproach.Thus,3DmouldXingqiangtheroughmachiningprocess,isactuallyaseriesof2.5DcomponentsXingqiangprocessing.Cutleryoptimizationistofindagroupofcutleryportfolio,allowingformaximumefficiencyremovalofmostmetals.Cutleryportfoliooptimizedbasicmethodsasfollows:
A.TodosomelongstepintoknifeinthedirectionofagroupofverticalandhorizontalsearchXingqianganotherentitytoformasearchlayer.
B.Deriveclosedtothecontours.
C.CalculatedbetweenCentralandoutsidetheislandorislandsandthedistancebetweenthekeythataffectcutlerychoicegeometricconstraintsalgorithmflowAsshowninfigure3
D.Accordingtotheprincipleofthemerger(adjacenttothecriticaldistancewillbesmallerthanthedifferencebetweenthethreshold)tosearchlayermerger,graphicprocessingandidentifyingviablecutlerysets,aprocessinglayer.
E.Determinetheuseofeachprocessinglayercutlery,cutleryXingqiangprocessingportfolio.
F.Accordingcutleryrecommendedprocessingparameters(cuttingspeed,depthandintoXianxiaotospeed),thecalculationofmaterialremoval.
G.Accordingtotheactualremovalofthevolumeprocessinglayer,theprocessingtimeforeachprocessinglayer.
H.Xingqiangcalculatingthetotalprocessingtimeandresidualvolume.
I.TheoverallportfoliooftheGroupcutleryprocessingefficiencyassessment.
J.Repeata~iuntilderiveoptimalmixofcutlery.Iftimeisthegoal,calledfortheentireprocessingtimetXingqiangshortestportfoliotooptimizecutlery.
2.2Semi-finishedcutlerychoice
Themainpurposeistoremovesemi-finishedroughmachiningresidualcontoursofthenewwarrants.Tocompletelyremoveheight,depthmustbegreaterthanXianxiaopartsofeachleveltothesurfacedistancex.Itsalgorithmstepsareasfollows:
Step1:
entitymodelsfrompartsoftwoadjacenttothecrosssectionofthesurfacecontoursandthecorrespondinglength;
Step2:
Theaveragelengthofcontours;
Step3:
calculateitswidth;
Step4:
calculatingheightfloortothesurfaceofpartstothelawdistancex;
Step5:
steps1~repeatsteps4,eachlevelofdecisionXianxiaodepth;
Step6:
calculatecutlerydiameterD,byorundercutleryexperienceD=x/0.6manualrecommended;
steps7:
chooseXianxiaoxdepththanthesmallestcutlery.
2.3finecutlerychoice
Finecutlerychoiceisthebasicprinciple:
cutlerypartssurfaceradiussmallerthanthesmallestsizeRcurveradiusr,thegeneraladmissionR=(0.8~0.9)r.Itsalgorithmstepsareasfollows:
Step1:
fromthesmallestcurveradiuscalculationmodelpartsentities;
Step2:
Fromcutlerydatabasesearchradiusoflessthanacutlerycalculatedradiusofthecurveallcutlery;
Step3:
selectthebestcutlerymeettheaboverequirements;
Step4:
Ifallcutlerythanthesmallestcurveradius,thesmallestchosenasarecommendedcutlery.
4summaryanddiscussion
Mouldtypeofcraftofprocessingplan,needhightechnologyandexperienceveryusually,prepareNCtimeofdatanearlyandprocesstimetobelarge.SopersonwhoproduceofcraftofprocessingplanandNCprocessdemandoftheorderrightawayseemfurthermoreurgentautomatically.
Thistextsystemresearchmouldtypeofcraftcutterplan,chooseproblem,putforwardmouldofroughmachining,halffinishmachining,finishmachiningprincipleandmethodthatcutterchooses,therealizationalgorithmwithcorrespondingstructure,andhascarriedontherealizationofpreliminaryprogrammingundertheenvironmentofUG/OPENAPI,havedevelopedCATSprototypesystem.Incuttertypeandonthefoundationthatthespecificationisfixed,systemalsocanrecommendparameterofprocessingaccordingtocuttermanual(cutpace,mill,sharpendepth,enterpersonwhogive,etc.),evaluatecorrespondingprocessingtime.FinalpurposeitstorealizeintegrationofCAD/CAMreally,producethroughaftertreatmentnumericalcontrolprocesstheorder.
Needtopointout,shouldimprovethemouldtypetotalityofandprocessefficiency,needitfromtheroughmachining,halffinishmachining,considerationonthewholeoffinishmachining,makeupandoptimizemanytargets,thiswillbeworkthatwe