精密注塑技術(shù)課件

精密注塑技術(shù)

AspectsforPreciseInjectionMoldingStarlitePlasticProducts(Kunshan)co.,ltd.MichaelYang內(nèi)容提要Overview

精密注塑的定義

DefinitionPreciseInjectionMolding鎖模系統(tǒng)ClampingUnit

鎖模力

ClampingForce選擇注射裝置的準(zhǔn)則CriteriatoSelecttheInjectionUnit

SELOGICA?

控制器

SELOGICA?Controller模具設(shè)計(jì)MoldDesign

模具溫度控制MoldTemperatureControl2精密注塑的定義DefinitionPreciseInjectionMolding小的尺寸和公差輕的部件重量為特定產(chǎn)品配備注塑設(shè)備

靈活的機(jī)器配備（一臺(tái)機(jī)器可適用于多種模具)

穩(wěn)定的質(zhì)量，高的重復(fù)性

SmallpartdimensionandtoleranceLowweightAdaptationofmachineperformancetothepartsFlexiblemachineconfiguration(manymoldssuitableforonemachine)Stablequality,reproducibility

3鎖模力ClampingForce 精密注塑的另一個(gè)重要因素是鎖模力。原因是：模腔更好的排氣（90%的空氣從分型面排出）減少機(jī)器和模具的磨損節(jié)省能源Oneotherimportantaspectforpreciseinjectionmoldingistheclampingforce.Reasonsforthatare:Muchbetterventingofthecavitiesduringinjection.(ca.90%oftheairinsidethecavityescapeoverthepartingline)Topreventmachineandmoldfromunnecessarywear.Savingenergy5鎖模力ClampingForce 怎樣計(jì)算鎖模力鎖模力=單位鎖模力X(產(chǎn)品投影面積+流道投影面積）如果有滑塊，需要將滑塊投影面積的30%加入產(chǎn)品投影面積Howtocalculatetheclampingforce?Ifthemoldcontainssliders!Youhavetoadd30%oftheprojectedsliderareatotheprojectedareaofmoldedpart.6鎖模力ClampingForce單位鎖模力的確定可使用以下圖表Todefinethenecessaryspecificclampingforce,useoneofthepicturesbelow.

Forstandardparts forthinwalledpartswithlongflowpaths7選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnitShotweightCycletimeMaterialInjectionpressure9每一機(jī)器尺寸Each

machine

size三個(gè)注射單元3injection

units三個(gè)料筒規(guī)格3cylinder

sizes選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnit模塊化Modularity10選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnit注射單元的歐洲橡塑機(jī)械協(xié)會(huì)(EUROMAP)規(guī)格表示注射單元的最大注射功。計(jì)算方法最大注射壓力X最大行程容量/1000舉例按注塑機(jī)320C600-250規(guī)格表最大注射壓力(35mm螺桿）：1820bar最大行程容量144ccm1820barX144ccm/1000250ThesizeoftheinjectionunitisaccordingtoEUROMAPandindicatestheworkingperformanceoftheinjectionunit.Theworkingperformanceiscalculatemax.spec.injectionpressurexmax.strokevolume/1000Example:Accordingtothetechnicaldataof320C600-250Max.Injectionpressure(screwdiameter35mm)=1820barMax.Strokevolume=144cm31820barx144cm3/100025011選擇注射量的準(zhǔn)則Selectioncriteriashotvolume最大計(jì)量容量max.dosagevolume20–80%最佳工作范圍opt.workingrange10–20%bzw.80–90%可接受的范圍conditionalsuited<10%bzw.>90%不推薦的范圍notrecommended選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnit13選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnitExample:Connector(PA6),8cavities,26.5gshotweight

Resultsaccordingthelistbelow:(1)Theinjectionvolumemustbeonaverage25%greaterthanthevolumeoftheinjectedpart(incl.sprue)duetoshrinkageduringsolidifyingandduetothecompressionofthemeltduringinjection.Injectionunit100100250250Screwdiameter20mm25mm30mm40mmMax.injectionvolume31cm349cm3106cm3188cm3Percentageofcapacity95%60%28%16%14選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnitExample:Connector(PA6),8cavities,26.5gshotweight

2ndexample,calculationwithshotweight

Resultsaccordingthelistbelow:Injectionunit100100250250Screwdiameter20mm25mm30mm40mmMoldedpartweight26g41g89g158gPercentageofcapacity100%64%30%17%15選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnitExample:Connector(PA6),8cavities,26.5gshotweight(29.31

cm3)

Resultaccordingtothelistbelow,dwelltimeforPA6min.60sec.Injectionunit100100250250Screwdiameter20mm25mm30mm40mmScrewchannelvolume60cm385cm3185cm3265cm3Cycletime15s/dwelltime25sec.35sec.75sec.109sec.Cycletime25s/dwelltime41sec.58sec.126sec.181sec.Remarks:anextendedscrewandcylindercanincreasethedwelltime!17選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnitSelectioncriteriamaterialthroughput

Example:Connector(PA6),8cavities,26.5gshotweightInjectionunit100100100250250Screwdiameter20mm25mm30mm30mm40mmMax.Throughput/h(PA-GF30)3.5kg/h5kg/h6kg/h11kg/h15,5kg/hThroughput(cycletime15s)6.4kg/h6.4kg/h6.4kg/h6.4kg/h6.4kg/hThroughput(cycletime25s)3.8kg/h3.8kg/h3.8kg/h3.8kg/h3.8kg/hMax.Throughput/h(PS)5.5kg/h8kg/h9.5kg/h17kg/h24.5kg/hThroughput(cycletime15s)6.4kg/h6.4kg/h6.4kg/h6.4kg/h6.4kg/hThroughput(cycletime25s)3.8kg/h3.8kg/h3.8kg/h3.8kg/h3.8kg/h18錯(cuò)誤的選擇會(huì)造成Mistakesinselectioncausese.g.to

-不完全熔化的粒料 -Unmeltedgranulate -混色不均 -Colorsteaks -燒焦 -Burntstreaks選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnit19選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnits

-注射控制的方式--conceptionsofinjectionregulation-標(biāo)準(zhǔn)方式：注射閉環(huán)控制basicconfiguration injectionregulation擴(kuò)展方式（可選件）：螺桿精確定位extensionstage(option) positionregulationscrew(PRS)21注射閉環(huán)控制的原理Functionprincipleoftheinjectionregulation選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnits

螺桿精確定位Positionregulatedscrew22螺桿精確定位的原理Functionprincipleofthepositionregulatedscrew選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnits

Injectioncontrol

注射控制Positionregulatedscrew螺桿精確定位230,005ccm0,025ccm0,010ccm0,040ccm0,035ccm0,015ccm效果舉例（改變進(jìn)料量）Examplefortheefficiency(variationdosagevolume):選擇注射單元規(guī)格的準(zhǔn)則

CriteriatoSelecttheInjectionUnits25注射閉環(huán)控制與螺桿精確定位比較

InjectionregulationincomparisonwithpositionregulationInjectionspeedcurvepressurecurveinjectionspeedscrewpositionpressurecurvepositionregulationpressurecurveinjectionregulation26模具設(shè)計(jì)方面

AspectofMouldDesign流道設(shè)計(jì)(特別是小產(chǎn)品)用冷流道流道長(zhǎng)度取決于模具剛性和復(fù)雜程度必須選擇足夠的橫截面積用熱流道加熱的流道增加材料滯留時(shí)間熱流道需要足夠的空間延長(zhǎng)的噴嘴需要注意事項(xiàng)與熱流道相同需要附加的加熱圈SprueDesign(especiallysmallparts)Viacold-runnersystemSpruelengthistheresultfrommoldstabilityandmoldcomplexityThespruesectionmustbeselectedbigenough

Viahot-runnersystemsHeatedspruechannelincreasesthedwelltimeProblemswithspaceViaextendednozzletipSameproblemlikewithhot-runnersystemsAdditionalheaterbandnecessary!27模具設(shè)計(jì)方面

AspectofMouldDesign研磨方向互相交叉排氣容易,90%空氣從分型面排出

Easyventing.approx.90%ofairescapesoverpartingline

空氣可從整個(gè)模腔接觸面排出Theaircanescapeoverthecompletecavityarea

成本低Lowcosts1–分型面光潔度0.007–0.009mm1–partinglineroughness0.007–0.009mm2–模芯光潔度0.003–0.004mm2–cavityinsertroughness0.003–0.004mm29排氣槽Ventingchannel

在流道終點(diǎn)或熔體相交處Attheendoftheflowpathorwherethemeltfrontsmeetstogether

可隨時(shí)開出Afterwardscreationpossible

會(huì)積累臟物，需定時(shí)清理

Problemsofdirtdepositionthusoftencleaning

模具設(shè)計(jì)方面

AspectofMouldDesign1–ventingchannel(0.01–0.02mm)30溢流槽排氣Overspillventing在流道終點(diǎn)或熔體相交處Attheendoftheflowpathorwherethemeltfrontsmeettogether排氣效果好Goodventing

防止熔合線Preventionfromweldlinesinthatarea

需切掉余料Afterwardsremovalofoverspillchannel模具設(shè)計(jì)方面

AspectofMouldDesign1–meetpointwithenclosedair

2–injectionpoint

3–overspillchannel(ventingthroughmeltfrontmeetpointshiftingintooverspillchannel31模具設(shè)計(jì)方面

AspectofMouldDesign對(duì)中系統(tǒng)centeringsystem對(duì)中系統(tǒng)centeringsystem32模具設(shè)計(jì)方面

AspectofMouldDesign對(duì)中系統(tǒng)centeringsystem33模溫控制

MoldTemperatureControl模具溫度直接影響產(chǎn)品質(zhì)量的穩(wěn)定性Themoldtemperaturehasadirectinfluenceofthereproduciblequalityofthemoldedparts.34

溫度感應(yīng)器安裝于模具內(nèi)利于優(yōu)化控制模溫機(jī)與機(jī)器通訊

如模溫機(jī)故障，機(jī)器停機(jī)整個(gè)系統(tǒng)內(nèi)存水量少（3升），傳熱好，調(diào)節(jié)穩(wěn)定模腔溫度公差±1流量監(jiān)視OptimalmoldtemperaturecontrolviaexternalsensorplacedinthemoldCommunicationfromtemperaturecontrolunittomachineincaseofmalfunctionproductionstop!Besttemperatureregulationthroughreductionofheattransfermediumtoapprox.3literinthe