1、脫模壓力:原則上應大於塑料射入模具(jù)的總壓力,以無毛刺為基準。
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係(xì)。目(mù)的是使原料均勻、徹(chè)底地進入模具,並以適量的量填滿每個角落。如果太低,會造成短射和縮水。如果太高,會出現毛刺、過飽(bǎo)和、粘模(mó)、燒(shāo)焦(jiāo)、易損模(mó)具和高內應力。
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(de)快慢決定了原料在模流道和成品中的狀況,如毛刺、過飽和、焦燒(shāo)、短射、縮孔、粘結不良(liáng)、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,溶液顏色過低,成品內應(yīng)力增大(dà)。如果溫度太低,壓力太高,可能會導致螺絲斷裂。溫度過高,產品有毛刺,冷卻產生溫差,造(zào)成收縮。原料易分解、變黃、變色、斷裂。冷卻時間變長,氣體不(bú)易排出,會有氣體(tǐ)。
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:螺杆(gǎn)在旋轉進料時後退的阻力稱為背壓。它(tā)的作用是使原料在(zài)輸送和壓縮中更加緊密。原料(liào)的空氣和水分(fèn)可以從(cóng)螺杆後部排出。使溶膠(jiāo)不含影響成品表(biǎo)麵的氣體成分。低層會有氣泡,表麵呈銀色。高(gāo)會過熱、結塊、溢膠,周期(qī)長(zhǎng),螺絲(sī)不退(tuì)。同時鬆的應用很重要:背(bèi)壓(yā)低時,有的原料需要鬆,有的不需要鬆(超過背壓根據原料調整不同的屬性)。背壓(yā)高(gāo)時,一定要用鬆背,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、模具溫度和冷卻時間會影響成品的粘模(mó)、收縮、尺寸公差、表麵光亮度、周期等,應根據實際情況及時調整。另外,亞克力、PC等(děng)成品(pǐn),肉(ròu)厚時一定要有模溫,這樣才不會(huì)產生氣泡和應力(lì)。
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.