要提升济南模具加工的精密度，条件有很多，其中最本质的是塑料材料、注塑模具、注塑工艺和注塑设备这四项基本因素。我们设计塑料外壳模具时，应首先选定工程塑料材料，而能进行精密塑料外壳加工的工程塑料又必须选用那些力学性能高、尺寸稳定、抗蠕变性能好、耐环境应力开裂的材料。其次应根据所选择的塑料材料、成品尺寸精度、件重、质量要求以及预想的模具结构选用适用的注塑机。To improve the precision of the mold processing in Ji'nan, there are many conditions, the most essential is the plastic materials, injection mold, injection molding process and injection molding equipment, these four basic factors. We design the plastic shell mold, should be first selected engineering plastics materials, and can carry out precision plastic shell processing engineering plastics must choose those high mechanical properties, dimensional stability, good creep resistance, environmental stress cracking resistance of materials. Second, according to the selection of plastic materials, product size precision, weight, quality requirements and the expected mold structure to choose the appropriate injection molding machine.

1.关模压：济南模具加工原则上应大于塑胶射入模内的总压，以不出毛边为基准。Mold closing: Ji'nan mold processing principle should be greater than the plastic injection mold in the total pressure, with no burr as the benchmark. 　　

2.压力和速度：压力和速度有部分相同的关系作用于模内。目的使原料进入模内能均匀，彻底，适量的充满各角落.太低会短射，缩水，太高有毛头，过饱，粘模，烧焦，易损模具及内应力高等不良现象。Pressure and speed: pressure and velocity have the same effect on the mold. Objective to make the raw material into the mold can be uniform, thorough, full of every corner. The amount is too low will shrink, short shot, too high a feather, satiety, sticking, burning, and internal force of die wearing higher adverse phenomenon.

3.速度：济南模具加工的速度的快慢决定原料在模具浇道内及成品中之状况，快有毛边，过饱，烧焦，慢了出现短射，缩水，结合不良易断等。　Speed: the speed of mold processing in Ji'nan determines the raw material in the mold and the situation in the finished product, fast edge, too full, burnt, slow the emergence of short shot, shrink, combined with bad easily broken. 　

4.温度：原料不同，温度各异，太低溶液胶颜色不均，成品内应力增大.因温度过低增压过高，可能引起螺杆断裂，过高，产品有毛边，又因冷却产生温差，引起收缩。此时，济南模具加工的原料会分解，变黄，变色，易断裂.冷却时间变长，气不容易排出，会有瓦斯气。Temperature: different materials, different temperature is too low, uneven color glue solution, the finished internal stress increases. Because the low temperature may cause excessive pressure, screw fracture, high product, a flash, because of cooling temperature difference, cause contraction. At this point, the Ji'nan mold processing materials will decompose, yellowing, discoloration, easy to break. Cooling time becomes longer, gas is not easy to discharge, there will be gas.