翻译原文-Moldflow Software in a Complex Plastic Shell Injection Mold Design.pdf
笔筒注塑工艺分析与模具设计(含ProE三维图)
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MOLDFLOWSOFTWAREINACOMPLEXPLASTICSHELLINJECTIONMOLDDESIGNZHENYUZHAO1,A,LONGLIAO1,B,FEITANG1,C,BAILIU1,D1SHENZHENINSTITUTEOFINFORMATIONTECHNOLOGY,SHENZHEN,CHINAAYXPZZY01163COM,BLIAOLSZIITCOMCN,CTANGFSZIITCOMCN,DLIUBENYTOMCOMKEYWORDSINJECTIONMOLD,MOLDFLOW,MOLDDESIGN,MPIABSTRACTTHEPAPERDESCRIBESTHEIMPORTANTROLEOFMOLDFLOWTECHNOLOGYANDSTATUSTHROUGHTHEAPPLICATIONOFMOLDFLOW/MPIMOLDFLOWPLASTICSINSIGHTSOFTWAREFORCAEUNDERACOMPREHENSIVEANALYSISOFTHESHELLMOLDS,INJECTIONMOLDINGPARAMETERSSUCHASMOLDTEMPERATURE,MELTTEMPERATURE,INJECTIONTIMEANDINJECTIONPRESSUREAREUSEDTOSIMULATETHEACTUALPRODUCTIONPROCESSTHISSHOWSTHEMOLDFLOWTECHNOLOGYPLAYSASIGNIFICANTROLEINTHEMOLDDEVELOPMENTPROCESSFOROPTIMIZINGPLASTICPRODUCTSDESIGN,PLASTICMOLDDESIGNANDINJECTIONPROCESSPARAMETERS,ETCINTRODUCTIONATPRESENT,MOSTINJECTIONMOLDDESIGNERSAREBASEDMAINLYONTHEIRYEARSOFEXPERIENCEINMOLDDESIGNDUETOTHEDIVERSITY,COMPLEXITYOFPLASTICWORKPIECESANDTHELIMITEDEXPERIENCEOFDESIGNERS,ITISDIFFICULTTOACCURATELYDESIGNALOWCOST,SHORTCYCLE,GOODQUALITYPRODUCTS,QUALIFIEDHIGHRATEOFMOLDANDCRAFTPROGRAMS,ANDDESIGNERSOFTENREQUIRESREPEATEDCONTINUOUSLYINORDERTOTRYOUTWITHTHEREVISEDMODELFORMALLYPUTINTOPRODUCTION,SOMEBEYONDREPAIRDUETOTHEPRECISIONDIESCRAPMOLDFLOWTECHNOLOGY1HASAGREATADVANTAGETOIMPROVINGPRODUCTIVITY,ENSUREPRODUCTQUALITY,ORREDUCECOSTS,REDUCELABORINTENSITYANDSOONMOLDFLOWTECHNOLOGYCANBEUSEDINMOLDPROCESSINGPRIORTOUSECOMPUTERSTOSIMULATETHEENTIREINJECTIONMOLDINGPROCESSANALYSIS,TOPREDICTTHEMELTFILLING,PACKING,AIRTRAPS,WELDLINES,TEMPERATUREATFLOWFRONTANDWARPAGE,ETC26,SOTHATDESIGNERSCANEARLYDETECTIONOFPROBLEMS,REVISEPLASTICPARTSANDMOLDDESIGN,REDUCEANDEVENAVOIDMOLDREWORKSCRAP,IMPROVEQUALITYANDREDUCETHECOSTOFPLASTICPARTSANDSOONMOLDFLOWTECHNOLOGYHASSIGNIFICANTTECHNICALANDECONOMICSIGNIFICANCEINTHEPAPER,APLASTICSHELLINJECTIONMOLDISSELECTEDASANFLOWANALYSISEXAMPLE,MOLDFLOWSOFTWARETOOPTIMIZETHEDESIGNOFMOLDSFORPLASTICINJECTIONPRODUCTS,MOLDFILLING,COOLING,WARPAGEANDOTHERBEHAVIOROFTHEDYNAMICSIMULATIONFORTHEPRODUCTS,MOLDDESIGNANDDETERMINATIONOFINJECTIONMOLDINGPROCESSPARAMETERSPROVIDESATHEORETICALBASISINORDERTOIMPROVETHEQUALITYOFMOLDINGPRODUCTSMOLDINGPROCESSANALYSISTHEPRODUCTFORTHEPLASTICSHELLPARTSISSHOWNINFIG1,USINGABSPLASTIC,ANDTHEOUTERSURFACEHASTHEHIGHERQUALITYREQUIREMENTSINTHEPAPER,MPIMODULEISUSEDTOPROCESSTHEPRODUCTFLOWANALYSISINTHEANALYSIS,THROUGHTHEPROCESSFLOWSIMULATIONANALYSISISDETERMINEDTHEGATELOCATION,QUANTITYANDPROCESSCONDITIONS,ANDTHEPROCESSFLOWSIMULATIONISPREDICTEDTHECAVITYPRESSUREDISTRIBUTION,TEMPERATUREDISTRIBUTION,CLAMPINGFORCESIZE,ETC,FORTHEACTUALMOLDINGTOPROVIDEMOLDINGPROCESSPARAMETERSAFTERCOMPLETINGTHEABOVEANALYSIS,THEINJECTIONMOLDINGMATERIALISSELECTEDINTHESOFTWARE,THEREAREMANYLARGECOMPANIESOFPRODUCTSTOCHOOSEFROMINTHECASEMATERIALSELECTABSTYPE,PARAMETERSETTINGISINTAB1TAB1MOLDFLOWANALYSISPARAMETERSETTINGSINJECTIONMOLDINGTEMPERATURE230G263FORMINGCONTROLFILLINGCONTROLPRESSURE90MPAMOLDTEMPERATUREPUNCH55G263SPEED/PRESSURECONVERSIONAUTOMATICDIE80G263PACKINGPRESSURECONTROL80INJECTIONPRESSURE6SAPPLIEDMECHANICSANDMATERIALSVOLS29322010PP646650ONLINEAVAILABLESINCE2010/AUG/13ATWWWSCIENTIFICNET2010TRANSTECHPUBLICATIONS,SWITZERLANDDOI104028/WWWSCIENTIFICNET/AMM2932646ALLRIGHTSRESERVEDNOPARTOFCONTENTSOFTHISPAPERMAYBEREPRODUCEDORTRANSMITTEDINANYFORMORBYANYMEANSWITHOUTTHEWRITTENPERMISSIONOFTTP,WWWTTPNETID58175214,THEUNIVERSITYOFMANCHESTER,MANCHESTER,UNITEDKINGDOM11/01/14,031949MPIWILLAUTOMATICALLYGENERATETHEBESTGATELOCATIONOFRELEVANTINFORMATIONANDTOGRAPHICALLYDISPLAYTHEBESTGATEREGION,THEDEEPERTHECOLORTHEMORESUITABLEAREASELECTEDASAGATEACCORDINGTOFIG1THEPLASTICMODELSHOWSASYMMETRICALSTRUCTURE,ANDTHEBESTLOCATIONISTHEMIDDLEREGIONINTHEPAPERFIG1PLASTICSHELLMODELFIG2FILLTIMEMOLDFLOWANALYSISINTHEPAPERMPISOFTWAREISUSEDTOANALYSISTHEFILLTIMEANDFILLINGPRESSURE,WELDLINES,AIRTRAPS,MAXIMUMCLAMPINGFORCEANDWARPAGETHROUGHTHEANALYSISOFTHESEPARAMETERS,THEBESTINJECTIONPROGRAMSARESELECTEDFILLTIMEGATINGSYSTEMDESIGNDIRECTLYAFFECTSTHEMELTFILLINGBEHAVIOR,WHILETHEFILLINGANALYSISOFTHEIRULTIMATEGOALISTOGETTHEBESTGATINGSYSTEMDESIGNFILLANALYSISISFROMTHEBEGINNINGTOTHECAVITYTHATISFILLEDWITHINJECTIONOFTHEENTIREPROCESSOFANALYSISOFTHEFLOWFRONTLOCATIONTHEANALYSISUSEDTOPREDICTTHEFILLINGBEHAVIOROFWORKPIECEISREASONABLE,WHETHERTHEBALANCEOFFILLING,WHETHERTOCOMPLETETHEWHOLEWORKPIECEFILLFILLINGTHEPURPOSEOFTHEANALYSISISTOOBTAINTHEBESTGATELOCATION,GATENUMBERANDTHEBESTCASTINGSYSTEMLAYOUTFIG2SHOWSTHERESULTSOFTHEANALYSISOFFILLINGTIMETHROUGHTHEDIFFERENTSHADESOFCOLOR,THECHANGEOFSTATEASWELLASTHEMELTFLOWDURINGFILLINGISREFLECTED,FROMWHICHCANSEEWHETHERTHECAVITYISFILLED,ANDWHETHERTHEPROCESSOFFILLINGISBALANCEASCANBESEEFROMFIG2,FILLINGTIMEIS2825S,ANDTHECOLORSHADEISSOFTERTRANSITIONTHEINDICATESTHATTHEFILLINGPROCESSISRELATIVELYFLAT,ANDTHATTHEENTIREINJECTIONMOLDEDPARTSCANBEFILLEDWITHINASHORTPERIODOFTIME,LIQUIDITYBALANCEOFGOODANDFILLINGANDREASONABLESITUATIONTHUSTHEANALYSISCANBEPROVEDTHATGATINGSYSTEMDESIGNSHOWNINFIGURE2ISFEASIBLEAIRTRAPSTHECIRCLESHOWNINFIG3ISAIRTRAPAIRTRAPLOCATIONMAPISSHOWNINTHEFIGUREMELTFRONTBUBBLESGATHEREDININJECTIONPARTSWITHINORCAVITYSURFACEAREBASICALLYAROUNDTHELATERALSIDEOFTHEINJECTIONPARTS,ANDCONCENTRATEDINTHEPARTINGSURFACEINTHECASEAIRTRAPSMAINLYINTHEINNERSURFACEOFPLASTICSHELL,ANDMOSTAPPEARINTHEPARTINGSURFACE,ASSHOWNINFIG3SOAIRINTHEMELTFILLINGWILLAUTOMATICALLYDISCHARGE,THEAIRTRAPSDOESNOTAFFECTTHEAPPEARANCEOFTHEQUALITYOFTHEPRODUCTTHEREFORE,THECASEOFGASVERYEASILYTHROUGHTHEMOLDPARTINGSURFACEGAPDISCHARGE,THEREISNOTRAPPEDAIRPHENOMENON,WHICHCANEFFECTIVELYPREVENTTHEFORMATIONOFAIRTRAPSINJECTIONMOLDEDPARTS,ANDSCORCHTHESURFACEDEFECTSSUCHASDEFECTIVEFIG3AIRTRAPSFIG4WELDLINESAPPLIEDMECHANICSANDMATERIALSVOLS2932647WELDLINESWHENTWOORMOREOFTHEFLOWFRONTINTEGRATION,ITWILLFORMAWELDLINEINTHEWELDLINEPOSITIONTHEMOLECULESARETENDTOCHANGESTRONGLY,SOTHATTHEMECHANICALSTRENGTHSIGNIFICANTLYWEAKENEDINTHEPOSITION,ANDWELDLINEISNOTVISUALLYOBVIOUSINTHISCASE,INCREASINGTHEMOLDTEMPERATUREANDMELTTEMPERATUREMAKETWOMELTENCOUNTERSMERGEBETTERITISADVISABLETOINCREASETHESCREWSPEEDORIMPROVETHEDESIGNOFGATINGSYSTEMTOREDUCETHEFRICTIONGENERATEDHEAT,WHILEMAINTAININGMELTFLOWRATETOREDUCEFLOWCHANNELDIMENSIONSIFWELDLINESCANNOTELIMINATED,THENTHEYSHOULDBELOCATEDTHEPLACETHATITISLESSSENSITIVEONTHEWORKPIECEAREATOPREVENTTHEIMPACTOFTHEMECHANICALPROPERTIESANDAPPEARANCEOFWORKPIECEQUALITYBYCHANGINGTHEGATELOCATION,ORTOCHANGETHEWORKPIECETHICKNESSCANCHANGETHELOCATIONOFWELDLINESTHEWELDLINESPOSITIONISSHOWNONTHEPLASTICPIECESINFIG4AFTERAMOLDFLOWOPTIMIZATIONANALYSIS,IMPROVINGTHEDIETEMPERATURE,INCREASINGADEQUATETHEGATEANDREDUCINGAPPROPRIATELYCLAMPINGFORCE,OPENINGOFTHEEXHAUSTSYSTEMINTHEWELDINGSEAM,THEPRODUCTWELDLINESWILLBECOMEOBVIOUS,REDUCEDSCRAPRATES,TOMEETACTUALPRODUCTIONNEEDSTHERESULTSFROMFIG4CANBESEENTHATTHEREISNOLARGEAREAANDCONTINUOUSWELDLINES,SOWORKPIECESURFACEQUALITYWILLNOTBEAFFECTEDSINKINDEXSHRINKAGELINESREFERTOTHEPHENOMENONOFSURFACEDEPRESSIONSINTHEMOLDINGSALTHOUGHTHESEDEPRESSIONSARESMALL,BUTASLONGASVIEWINGFROMDIFFERENTANGLES,BUTITISVISIBLESHRINKAGELINESVISIBILITYANDITSSURFACETEXTUREISTHEROLEOFTHECOLORCOMPONENTS,SODEEPISTHEDISTINGUISHINGCRITERIATHEMAINREASONOFLINESAPPEARANCEISTHATINTHECOOLINGPROCESSHEATISCONTRACTEDFIGURE5SHOWSTHEDEPTHOFSHRINKAGELINESINTHECASELINESDEPTHISVERYSMALL,SHRINKLINESVERYCLEARLYDOESNOTAFFECTTHEPRODUCTSAPPEARANCEFIG5SINKINDEXFIG6CLAMPFORCECLAMPFORCEINTHEINJECTIONPROCESS,DUETOEXPANSIONFORCEOFMELTWITHINTHEMOLD,MOLDPARTINGSURFACEMAYSEPARATE,RESULTINGINTHEFLYINGSIDE,ITISNECESSARYFORTHEINJECTIONMOLDMACHINETOPROVIDEALOCKINGFORCE,ANDTHEFORCEKNOWNASTHECLAMPINGFORCEWITHTHEFORCECANOFFSETTHECAVITYEXPANSIONFORCEGENERATEDBYMELTUSUALLYCLAMPFORCESHOULDBEASSMALLASPOSSIBLETHESMALLERCLAMPINGFORCECANNOTONLYSAVEENERGY,REDUCECOSTS,BUTALSOTOEXTENDTHESERVICELIFEOFINJECTIONMOLDINGMACHINESANDMOLD,WHILETHEMOLDISALSOANEXHAUSTCANBECARRIEDOUTSMOOTHLY,SOTHATTHEMOLDFILLINGSTATEISMOREEASILYCONTROLLEDININJECTIONMOLDINGTHECLAMPINGFORCEDISTRIBUTIONISSHOWNINFIG6THEMAXIMUMCLAMPINGFORCEIS86KN,THERESULTSOFTHEANALYSISCANBEUSEDTOHELPDESIGNERSTOCHOOSEDIFFERENTTYPESOFINJECTIONMOLDINGMACHINEASCANBESEENFROMFIG5,THEMACHINERYCANMEETTHEREQUIREMENTSANDISCAPABLEOFNORMALPRODUCTIONRECOMMENDEDRAMSPEEDFIG7ISTHERECOMMENDEDRAMOFTHEPROGRAMGRAPH,ANDITSROLEINTHEREGULATIONOFRAMINTOTHECAVITYOFTHEINJECTIONSPEED,SPEEDOFINJECTIONMOLDFILLINGPROCESSTOENSURECONSISTENT,WILLHELPTOIMPROVETHESURFACEQUALITYOFWORKPIECESANDTOAVOIDEXCESSIVESHEARSTRESSTHEINJECTIONSPEEDISRECOMMENDEDTOMAKEAMOREUNIFORMRATEOFFLOWFRONT,WHICHWILLHELPTOELIMINATETHEPRESSUREPEAK,ANDATTHESAMETIMECANIMPROVEWORKPIECESURFACEFINISHINFIG7XYPOSITIONBYINJECTIONPRESSUREMAPCANEASILYSHOWTHECHANGESINPRESSURETEMPERATURETEMPERATUREMAINLYINCLUDESTEMPERATUREATFLOWFRONTANDBULKTEMPERATUREATTHEENDOFFILLINGTHEINTEGRATEDUSEOFTEMPERATUREATFLOWFRONTANDTHEWELDLINEGRAPHCANBEANALYZED648APPLIEDMECHANICSANDMECHANICALENGINEERINGWHETHERWELDLINEQUALITYISGOODORBADTHENARROWERTHESIZERANGEOFTEMPERATUREDISTRIBUTIONISATTHEENDOFFILLING,THEBETTERMOLDQUALITYISTWOKINDSOFTHERMALANALYSISRESULTSARESHOWNINFIG8ANDFIG9THERMOPLASTICPOLYMERFLOWANALYSISISUSUALLYUSEDTOPREDICTTHEFLOWBEHAVIORINSIDETHEDIEMOLDFLOWSIMULATIONBEGINSTOMELTFROMTHEINJECTIONSITESPREADTOTHEADJACENTPOINTOFTHEFLOWFRONT,UNTILTHEFLOWFRONTTOSPREADANDFILLWORKPIECEANDTHELASTPOINTTOCOMPLETETHEFLOWANALYSISANDCALCULATIONTHEOBJECTIVEISTOOBTAINTHEBESTPACKINGSTAGESETTIME,THEREBYREDUCINGASMUCHASPOSSIBLECAUSEOFTHEWORKPIECEBYTHEHOLDINGPRESSURECONTRACTION,WARPINGANDOTHERQUALITYDEFECTSAREASONABLETEMPERATUREDISTRIBUTIONATFLOWFRONTSHOULDBEUNIFORM,ANDTHEMODELCANNOTBEMUCHDIFFERENCEINTEMPERATUREASCANBESEENFROMFIG8,THEMODELISMOREUNIFORMTEMPERATUREDISTRIBUTIONMODELSHOWSTHATTHEMELTTEMPERATUREINTHEFLOWOFSLOWDECLINE,WHICHWILLHELPFILL,ANDASMALLERDROPINTHETEMPERATUREOFTHEPRODUCT,WHICHMEANSTHATTHESURFACEQUALITYOFPLASTICPARTSWILLBEGUARANTEEDFIGURE8SIMULATIONRESULTSFORTHEFLOWFRONTTEMPERATUREASCANBESEENFROMFIG8,MATERIALFLOWANALYSISCANBESEENTHATTHEMAXIMUMTEMPERATURETHEFOREFRONTIS2306,THELOWESTTEMPERATUREIS2238,INJECTIONMOLDEDPARTSOFTHETEMPERATUREDIFFERENCEIS68,THERECOMMENDEDVALUESOFTHECONTROLVALUE20WITHININDICATEDTHATASMALLERTEMPERATUREDIFFERENCE,WHICHMEANSTHEQUALITYOFTHESURFACEOFINJECTIONMOLDEDPARTSAREGUARANTEED,WORKPIECESCANBEFILLEDFIG8SHOWSTHATWHENTHEMATERIALFUSIONTEMPERATUREIS22892306,THELOWESTMELTTEMPERATUREISONLYLOWERTHANTHEINJECTIONTEMPERATUREOF2238SOMATERIALSCANBEAVERYGOODFUSION,ANDDOESNOTAPPEARWELDCAVITATIONSARESEENINTHEFUSIONLINEANDPARTINGSURFACE,ANDEXHAUSTDUCTSARESETATTHEOPENINGOFWELDLINETHISISNOTONLYCONVENIENTTOEXHAUST,BUTALSOINCREASETHEFUSIONLINEOFFASTNESSFROMTHEFIG8FLOWFRONTTEMPERATUREGRAPHANDFIG4WELDLINEGRAPH,WECANSEETHEFORMATIONOFWELDLINESWHENTHEMELTTEMPERATUREISABOUT230THEWELDLINEISNOTOBVIOUS,ANDTHERESULTSAREBESTBULKTEMPERATUREHASREFLECTEDTHESHEARHEATPRODUCEDINSIDETHEWORKPIECEIFTHEWORKPIECEHASASTRONGSHEARWITHINTHEROLE,WORKPIECETEMPERATUREWILLRISEINTHEMOLDFILLINGSTAGE,THEVOLUMECANBESEENFROMFIG9THATTHETEMPERATUREDIAGRAMSPEEDWEIGHTEDAVERAGETEMPERATURESHOULDBEVERYUNIFORMTHEMINIMUMTEMPERATUREIS1773C,ANDTHEMAXIMUMTEMPERATUREIS2343CTHECHANGESMEETTHEBULKTEMPERATURECONTROLLEDRANGEFIG7RECOMMENDEDRAMSPEEDFIG8TEMPERATUREATFLOWFRONTFIG9BULKTEMPERATUREFIG10PRESSUREATTHEENDOFFILLINGAPPLIEDMECHANICSANDMATERIALSVOLS2932649PRESSUREASCANBESEENFROMFIG10,THEPRESSUREDISTRIBUTIONISOBTAINEDATTHEENDOFFILLING,ANDANALYSISOFFILLINGPRESSUREDISTRIBUTIONISBALANCEDINTHEFINALFILLINGPRESSUREONTHELOWERPARTOFTHEBLUE,THEENTIREPLASTICPRESSUREDIFFERENCEISBELOW35MPAVOLUME/PRESSURECONVERSIONDATAANDFILLINGPRESSUREDATAATTHEENDOFFILLINGMOLDARETHESAMEEFFECTUSUALLY,THEVOLUMEANDPRESSURECONVERSIONTHROUGHOUTTHEINJECTIONMOLDINGCYCLEISTHEHIGHESTATTHISTIMETHESIZEANDDISTRIBUTIONOFPRESSURETHROUGHTHEPRESSUREPROFILECANBEOBSERVED,ANDWORKPIECEFILLBASICALLYREACH100ATTHECONVERSIONASCANBESEENFROMFIG11,THELARGESTINJECTIONPRESSUREIS5337MPAINMOLDINGPROCESS,ANDITISTHEREDINTHEDIAGRAMPOSITIONTHEGREYPARTINTHEFIGUREINDICATESTHATTHEWORKPIECE100FILLEDWITHGOODEFFECTPRESSUREATTHEINJECTIONLOCATIONPACKINGPROCESSBASEDONTHEFILLINGPROCESSISSIMULATEDBYOPTIMIZINGTHEINJECTIONOFREASONABLEFORCEANDPACKINGPRESSUREFORPRODUCTIONPREPARATIONFIG12SHOWSTHEPACKINGPROCESSOFSIMULATIONRESULTSINJECTIONPRESSUREFLOWISALSOKEYPARAMETERS,ADIRECTIMPACTONMOLDFILLINGGOODORBADASCANBESEENFROMFIG12,THEENDOFINJECTIONMOLDINGPRESSUREREACHESTHEMAXIMUM55MPA,LESSTHANTHEMAXIMUMINJECTIONMOLDINGMACHINE,PACKINGPRESSURECURVEANDSETTHEBASICLINEFIG11VOLUME/PRESSURECONVERSIONFIG12INJECTIONFORCEANDPACKINGPROCESSCONCLUSIONINTHEPAPER,MOLDFLOWSOFTWARETHROUGHTHEFLOWBEHAVIORISUSEDINTHESIMULATION,PREDICTION,ANDDISPLAYTHEFOREFRONTOFMEL
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