1、脫模壓力:原則上應(yīng)大于塑料射入模具的總壓力,以無(wú)毛刺為基準(zhǔn)。
demoulding pressure: in principle, it should be greater than the total pressure of plastic shot into the mold, with no burr as the benchmark.
2、壓力和速度在模具中作用有一些相同的關(guān)系。目的是使原料均勻、徹底地進(jìn)入模具,并以適量的量填滿(mǎn)每個(gè)角落。如果太低,會(huì)造成短射和縮水。如果太高,會(huì)出現(xiàn)毛刺、過(guò)飽和、粘模、燒焦、易損模具和高內(nèi)應(yīng)力。
Pressure and speed have some of the same relationship in the role of the mold. The goal is to get the material into the mold evenly and thoroughly, and fill every corner with the right amount. If it is too low, it will cause short shots and shrinkage. If it is too high, burrs, supersaturation, sticky molds, burning, brittle molds, and high internal stresses may occur.
3、速度:速度的快慢決定了原料在模流道和成品中的狀況,如毛刺、過(guò)飽和、焦燒、短射、縮孔、粘結(jié)不良、易破損等。
speed: the speed of the speed determines the raw material in the mold runner and finished products, such as burr, susaturation, coke, short shot, shrinkage, poor bonding, easy to damage and so on.
4、溫度:原料不同,溫度不同,溶液顏色過(guò)低,成品內(nèi)應(yīng)力增大。如果溫度太低,壓力太高,可能會(huì)導(dǎo)致螺絲斷裂。溫度過(guò)高,產(chǎn)品有毛刺,冷卻產(chǎn)生溫差,造成收縮。原料易分解、變黃、變色、斷裂。冷卻時(shí)間變長(zhǎng),氣體不易排出,會(huì)有氣體。
temperature: different raw materials, different temperatures, solution color is too low, the internal stress of the finished product increases. If the temperature is too low and the pressure is too high, the screw may break. Temperature is too high, the product has burr, cooling produces temperature difference, resulting in contraction. The raw material is easy to decompose, turn yellow, discolor, fracture. Cooling time becomes longer, the gas is not easy to discharge, there will be gas.
5、背壓:螺桿在旋轉(zhuǎn)進(jìn)料時(shí)后退的阻力稱(chēng)為背壓。它的作用是使原料在輸送和壓縮中更加緊密。原料的空氣和水分可以從螺桿后部排出。使溶膠不含影響成品表面的氣體成分。低層會(huì)有氣泡,表面呈銀色。高會(huì)過(guò)熱、結(jié)塊、溢膠,周期長(zhǎng),螺絲不退。同時(shí)松的應(yīng)用很重要:背壓低時(shí),有的原料需要松,有的不需要松(超過(guò)背壓根據(jù)原料調(diào)整不同的屬性)。背壓高時(shí),一定要用松背,注意空氣與溢膠的距離。
back pressure: the resistance of the screw back when rotating the feed is called back pressure. Its function is to make the material in transportation and compression tighter. Air and moisture of the raw material can be discharged from the back of the screw. The sol does not contain gas components that affect the surface of the finished product. There will be bubbles in the lower layers and a silvery surface. High will overheat, agglomerate, glue overflow, long cycle, screw does not retreat. At the same time, the application of loosening is very important: when the back pressure is low, some materials need to be loosened, and some do not need to be loosened (over the back pressure, different properties are adjusted according to the material). When the back pressure is high, be sure to use loose back, pay attention to the distance between air and rubber overflow.
6、模具溫度和冷卻時(shí)間會(huì)影響成品的粘模、收縮、尺寸公差、表面光亮度、周期等,應(yīng)根據(jù)實(shí)際情況及時(shí)調(diào)整。另外,亞克力、PC等成品,肉厚時(shí)一定要有模溫,這樣才不會(huì)產(chǎn)生氣泡和應(yīng)力。
mold temperature and cooling time will affect the finished product's sticking mold, shrinkage, dimensional tolerance, surface brightness, cycle, etc., should be adjusted in time according to the actual situation. In addition, acrylic, PC and other finished products, meat thickness must have mold temperature, so as not to produce bubbles and stress.