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塑料模具成型技术流程及参数介绍Moldingtechniqueprocedureandparameterintroduction第一節成型工艺Section1moldingtechnique.1.成型工艺参数类型Sortsofmoldingparameter.(1).注塑参数Injectionparameter.a.注射量Injectionrate.b.计量行程Screwbackpositionc.余料量Cushiond.防诞量Suckingbackratee.螺杆转速Screwspeedf.塑化量Plastic0rateg.预塑背压Screwbackpressureh.注射压力和保压压力Injectionpressureandholdingpressurei.注射速度Injectionspeed(2)合模参数Clampingparametera.合模力Clampingforceb.合模速度Clampingspeedc.合模行程.Clampingstroked.开模力Openingforcee.开模速度Openingspeedf.开模行程Openingpositiong.顶出压力Ejectoradvancepressureh.顶出速度Ejectoradvancespeedi.顶出行程Ejectoradvanceposition2.温控参数Temperatureparametera.烘料温度Dryresinmaterialtemperatureb.料管与喷嘴温度Cylindertemperatureandnozzletemperaturec.模具温度Moldtemperatured.油温Oiltemperature3.成型周期Moldingcyclea.循环周期Cycletimeb.冷却时间Cooltimec.注射时间Injectiontimed.保压时间Holdingpressuretimee.塑化时间Planttimef.顶出及停留时间Knockingoutanddelaytimeg.低压保护时间Moldprotecttime成型工艺参数的设定须根据产品的不同设置.Moldingtechniqueparametersettingdiffersdependingontypeofproduct第二节成型条件设定Section2MoldingparameterSetting按成型步骤:可分为开锁模,加热,射出,顶出四个过程.Moldingsteps:moldopening/closing,heatinginjectionandknockingout.开锁模条件:Moldopeningparameter:快速段中速度低压高压速度High-speedmid-speedLowpressurehighpressurespeed锁模条件设定:Moldclosingparametersetting1锁模一般分:快速→中速→低压→高压Moldclosing:high-speed→low-speed→lowpressure→highpressure2.快锁模一般按模具情况分,如果是平面二板模具,快速锁模段可用较快速度,甚至于用到特快,当用到一般快速时,速度设到55-75%,完全平面模可设定到80-90%,如果用到特快就只能设定在45-55%,压力则可设定于50-75%,位置段视产品的深浅(或长短)不同,一般是开模宽度的1/3.Inhigh-speedsection,Moldclosingspeeddependsontypeofmold.Fortwo–platemolditcansetquickandevenespeciallyquickusually,itsetspeedwithin55-75%.Forfull-platemolditsetspeedwithin80-90%whileusingespeciallyhighspeeditsetspeedwithin45-55%andpressurewithin50-75%positiondistancesettingdiffersdependingonthevolumeofproductandusuallyitcanbeset1/3ofmoldopeningposition.3.中速段,在快速段结束后即转换成中速,中速的位置一般是到模板(包括三板模,二板模)合在一块为止,具体长度应视模板板间隔,速度一般设置在30%-50%间,压力则是20%-45%间.Inmid-speedsection:Moldclosingspeedchangesintomid-speedafterhigh-speedsectionfinish.Mid-speedstartpositioniswheretwoplatesmeet(includethree-platemoldandtwo-platemold)Distanceofmid-speedisuptodistanceoftwoplatesplateitspeedwithin30-50%andpressure20-45%.4.低压设定,低速设定一般是在模板接触的一瞬间,具体位置就设在机台显示屏显示的一瞬间的数字为准,这个数字一般是以这点为标准,,即于此点则起不了高压,高于此点则大,轻易起高压.设定的速度一般是15%-25%,视乎不同机种而定,压力一般设定于1-2%,有些机则可设于5-15%,也是视乎不同机种不同.Low-pressuresection:Moldclosingsetslow-pressurewhenplatesmeeting.Thispositionissettothedataofmachinescreenonthistime.Thispointisthegageofthedata.Datalowerthepointthereisnohigh-pressure.Datahigherthepointthereishigh-pressureeasily.Itsetspeedwithin15-25%andpressurewithin1-2%dependingontypewithin1-2%dependingontypeofinjectionmoldingmachine.5.高压设定,按一般机台而言,高压位置机台在出厂时都已作了设定,相对来讲,是不可以随便更改的,比如震雄机在50P.速度相对低压略高,大约在30-35%左右,而压力则视乎模具而定,可在55-85%中取,比如完全平面之新模,模具排气良好,甚至于设在55%即可,如果是滑块较多,原来生产时毛边也较多,甚至于可设在90%还略显不足.High-pressuresection:Tonormalinjectionmoldingmachine,high-pressurepositionhadbeensetbeforetheyweresenttocustomer.Itcannotbemodified.Forexamplehigh-pressurepositionofCHENHSONGmachineis50P.Thespeedofhigh-pressuresectionisabout30-35%andhigherthanthatoflow-pressure.Thepressureisuptomold,itcansetwithin55-85%Forfull-platemold,it’sejectairwell,itcansetpressure55%.Ifmoldhasalotofslidesandflashratehighinproduction,pressurecanset90%.二.熔胶段工艺PlasticTechnique1.再复杂的熔胶旋转过程最多不会超过三段,因为熔胶本身就是存在于把胶熔进料筒的过程,如果原料粘度大,熔胶压力则大,但速度则应取决于原料的分解温度,熔胶速度越快,原料中的剪切力则会越大,料管温度则越高,局部原料产生分解的可能性则会越大,故一般熔胶会采用中速为宜,如45%-75%,熔胶同时会碰到一个比较重要的环节,那就是背压的使用,产品精度要求越大,背压的使用则更大,背压可使原料分子间结构更紧密,成型出的产品则尺寸更稳定,外观越好.当然,背压太大,则会产生流涎,所以背压的使用又应考虙到其它原因.Plasticshouldlower3steps,becauseplasticisasteptoaddmeltresinmaterialtocyclinder,Higherstickofresinmaterial,higherscrewbackpressure.Screwspeeddiffersdependingondecomposingtemperatureofresinmaterial,Higherscrewspeed,Highertrimforceofresin,highercyclindertemperature.Someresinmaterialmaydecomposessoitsetscrewspeedinmid-speedsuchas45-75%,Inplasticstepsettingscrewbackpressureisveryimportant,Higherscrewbackpressure,higherqualityofproductscrewbackpressuremakeresinstructureorder,Moldingproductisbeautifulandvolumestable.But,itmaybeflowifscrewbackpressuretoohigh.Soallfactorsshouldbeconsideredwhenusingscrewbackpressure.2.熔胶过程还有一个比较重要的环节,那就是松退,松退分前松退和后松退,其作用一般是为了防止流涎和抽丝,设定值速度和压力都在20%-50%间,设定的行程一般在2-5cm间,太长的行程可能会使料筒里面贮存空气,导致下一模出现不期望的气泡.Inplasticstepsuckingbackisveryimportanttoo.SuckingbackincludefrontsuckingbackandbacksuckingbackItsettingsuckingbacktopreventflowandline.Itsetssuckingbackspeedandpressurewithin20-50%anddistancewithin2-5cm.TOOlongdistancemakecyclinderreserveairandcausebubbleatnextmolding.顶出的工艺设定knockingouttechniquesetting产品经冷却定型后则有一个开模的过程,开模基本上是合模的反过程.开模的未段则有一个慢速设置,开模完成后,产品必须顶出的过程.Thereisamoldopeningstepafterproductcoolingtakingshape.Moldopeningisareversestepofmoldclosing.Thelaststepofmoldopeningspeedsetslow.Productshouldbeknockedoutaftermoldopened.一.顶前:Knockingout顶前最好分两个阶级,第一阶可分为中压慢速,即是把产品轻轻顶出一部分,然后是中压中速顶,中压中速一般指的是35%-55%,而低速则有可能低到5%,这需视产品不同而言,顶出行程设定是顶出长度稍比产品垂直深度大1-2cm即可.Knockingoutincludestwosteps,Step1sectionsettingmid-speed,knocksproductoutpartlystep2sectionsettingmid-pressureandmid-speed.Dependingo