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塑料模具成型技术流程及参数介绍
Molding technique procedure and parameter introduction
第一節 成型工艺 Section 1 molding technique. 1.成型工艺参数类型 Sorts of molding parameter. (1). 注塑参数 Injection parameter. a.注射量 Injection rate. b.计量行程 Screw back position c.余料量 Cushion d.防诞量 Sucking back rate e.螺杆转速 Screw speed f.塑化量 Plastic0 rate g.预塑背压 Screw back pressure h.注射压力和保压压力 Injection pressure and holding pressure i.注射速度 Injection speed (2)合模参数 Clamping parameter a.合模力 Clamping force b.合模速度 Clamping speed c.合模行程. Clamping stroke d.开模力 Opening force e.开模速度 Opening speed f.开模行程 Opening position g.顶出压力 Ejector advance pressure h.顶出速度 Ejector advance speed i.顶出行程 Ejector advance position 2.温控参数 Temperature parameter a.烘料温度 Dry resin material temperature b.料管与喷嘴温度 Cylinder temperature and nozzle temperature c.模具温度 Mold temperature d.油温 Oil temperature 3.成型周期 Molding cycle a.循环周期 Cycle time b.冷却时间 Cool time c.注射时间 Injection time d.保压时间 Holding pressure time e.塑化时间 Plant time f.顶出及停留时间 Knocking out and delay time g.低压保护时间 Mold protect time 成型工艺参数的设定须根据产品的不同设置. Molding technique parameter setting differs depending on type of product 第二节成型条件设定 Section 2 Molding parameter Setting 按成型步骤:可分为开锁模,加热,射出,顶出四个过程. Molding steps: mold opening/closing, heating injection and knocking out. 开锁模条件: Mold opening parameter: 快速段中速度 低压高压速度 High-speedmid-speed Low pressure high pressure speed 锁模条件设定: Mold closing parameter setting 1锁模一般分: 快速→中速→低压→高压 Mold closing: high-speed →low-speed →low pressure→high pressure 2.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. In high-speed section, Mold closing speed depends on type of mold. For two –plate mold it can set quick and even especially quick usually, it set speed within 55-75%. For full-plate mold it set speed within80-90% while using especially high speed it set speed within 45-55% and pressure within 50-75% position distance setting differs depending on the volume of product and usually it can be set 1/3 of mold opening position. 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. In mid-speed section: Mold closing speed changes into mid-speed after high-speed section finish. Mid-speed start position is where two plates meet (include three-plate mold and two-plate mold ) Distance of mid-speed is up to distance of two plates plate it speed within 30-50% and pressure 20-45%. 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-pressure section: Mold closing sets low-pressure when plates meeting. This position is set to the data of machine screen on this time. This point is the gage of the data. Data lower the point there is no high-pressure. Data higher the point there is high-pressure easily. It set speed within 15-25% and pressure within 1-2% depending on type within 1-2% depending on type of injection molding machine. 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-pressure section: To normal injection molding machine, high-pressure position had been set before they were sent to customer. It can not be modified. For example high-pressure position of CHENHSONG machine is 50P.The speed of high-pressure section is about 30-35% and higher than that of low-pressure. The pressure is up to mold, it can set within 55-85% For full-plate mold, it’s eject air well, it can set pressure 55% .If mold has a lot of slides and flash rate high in production, pressure can set 90%. 二.熔胶段工艺
Plastic Technique 1.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. Plastic should lower 3 steps, because plastic is a step to add melt resin material to cyclinder , Higher stick of resin material ,higher screw back pressure. Screw speed differs depending on decomposing temperature of resin material ,Higher screw speed ,Higher trim force of resin, higher cyclinder temperature. Some resin material may decomposes so it set screw speed in mid-speed such as 45-75%, In plastic step setting screw back pressure is very important, Higher screw back pressure , higher quality of product screw back pressure make resin structure order, Molding product is beautiful and volume stable. But ,it maybe flow if screw back pressure too high . So all factors should be considered when using screw back pressure. 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. In plastic step sucking back is very important too. Sucking back include front sucking back and back sucking back It setting sucking back to prevent flow and line. It sets sucking back speed and pressure within 20-50% and distance within 2-5cm. TOO long distance make cyclinder reserve air and cause bubble at next molding. 顶出的工艺设定 knocking out technique setting 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. There is a mold opening step after product cooling taking shape. Mold opening is a reverse step of mold closing. The last step of mold opening speed set slow. Product should be knocked out after mold opened. 一.顶前: Knocking out 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. Knocking out includes two steps, Step1 section setting mid-speed, knocks product out partly step2 section setting mid-pressure and mid-speed . Depending on different product, mid-pressure and mid-speed sets within 35-55% but low-speed can set 5%. Distance of knocking out longer 1-2cm than the vertical thickness of product. 二.退针 Back 顶退包括两个过程与顶落的过程基本一致,顶退的终点应预留1-3cm的空间,以保护顶针油管不被顶坏. The same as knocking out, ejector back includes 2 steps. To protect the ejector oil jar, it should make a 1-3mm distance in the ending point of ejector back. 三.顶针方式还包括一个多次顶,单次顶及顶针停留的选择,机械手取产品,脱模顺利的情况都采取多项, 为了顶针油缸 寿命的延长,多次顶就以不超过三次为宜,顶针停留一般用在顶针带着产品退回有可能对增品产生损伤的模具, 同时为配合机械手使用,有时也需要较短的顶针停留. The way of knocking out includes knocking out once, Knocking out repeat and ejector delay. Take product by manipulator or take product easy, it should select knocking out once. To longer the work time of ejector oiljar, times of knocking out lower 3 times. Ejector delay used when product will be damaged if ejector back or suit manipulator. 成型时间的设定 Molding time setting 在保证产品质量的前提下,周期时间是越短越好,周期时间又包括如下几项:射胶时间,保压时间,熔胶时间, 冷却时间,顶出时间,锁模低压时间,甚至乎关系到时间因素的还有还开模与锁模,及顶出的快慢. Cycle time should shorter on condition that product quality well. Cycle time includes: injection time , holding pressure time, plastic time, cure time, knocking out time and mold protect time. Even mold opening closing sopeed and knocking out speed affect cycle. 1. 射胶时间包含保压时间,一般看起来,射胶时间越长,产品越饱和,但我们在讲求质量时, 同时也须考虑产能更何况,射胶时间过长,有可能会造成产品过于饱满而导致粘模顶的变形呎寸偏大 等一系列问题,故我们在设置射胶时间时应综合考虑,尽量在合乎质量要求时缩短射胶时间. Injection time consists holding pressure time. Longer injection time, fuller product, we should consider production quantity when we suit for quality. If injection time too long, it may cause a series of defects suck as flash strain. So all sorts of factors should be considered, injection time should be shout if quality suit for requirement. 2. 熔胶时间的长短取决于熔胶速度设定的快慢,背压设定的大小,但有一点,熔胶时间控制的长短一定要比冷却时间短. Plastic time depends on plastic speed and screw back pressure, but plastic time must shorter than cure time. 3. 冷却时间:冷却时间的长短直接影响到成型的周期,冷却时间越长,成型时间就越长,造成产能就越低, 故我们在设定高压冷却时间时,只要能保证到产品成型顺利,不会直接影响到变形等问题,设定的时间也是越短越好. Cure time: Cure time affects molding cycle. Longer cure time, longer molding cycle, lower production quantity. So it sets cure time short on condition that product molding succed and can’t deformation.. 4. 在大量使用机械手的塑胶公司,我们的顶出时间一般是与机械手配合为宜,全自动使用机械手时顶出停留时间一般保持1.5-2秒, 半自动生产,如因顶针退回会导致产品掉落或卡紧,而取不下产品,停留时间则应保持5秒左右. In PCE company, for using manipulator in abundence , knocking out time suits manipulator, Knocking out delay keeps 1.5-2 second when using manipulator full-manipulator, knocking out delay keeps about 5 second when using manipulator semi-manipulator and product will fall or can’t be taken off if ejector back. 5. 低压保护时间对保护我们人身安全,模具安全起很大作用,配合好模具低压位置和低压压力的调整, 低压保护的时间应取1-3秒,保护时间越短,可能造成的危害则越小. Low-pressure protect is very important for safety and protect mold, Mold protect time should adjust within 1-3 second suit low pressure and position of mold protect, shorter protect time, make damaged. ************************************************************************************************************************************************************************
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