What is Injection Molding shrinkage reason?
No 1: insufficient cavity packing caused by injection molding shrinkage. Is divided into six kinds of circumstances:
A plastic part thickness or thickness is not uniform, the solution for mould in China is to modify the mould or increasing the injection pressure;
B, the material is not enough, China injection molding solution is to increase the material;
C, the injection pressure is too small, the solution is to increase the injection molding pressure;
D, injection time is too short, the solution is to extend the injection molding time;
E, asymmetry of the gate, the solution is to limit all melt into recent sprue gate, forced melt into the other gate;
F, the injection speed too slow, the solution is to increase injection molding speed;
G, the gate is too small, the solution is to increase the gate size.
How to solve？
1: overheating of plastic raw materials; Improved method is to reduce barrel temperature and mould temperature is controlled properly overheated parts.
2: plug injection molding pump (heart) before melt cushion pressure unstable; The solution is to increase the material and keep the injection plug (pump heart) before melt cushion pressure stability.
3: injection mold opening time is different; To improve the method is to use a timer control mould time.
4: plug injection pump (heart) melt rubber cushion product before too much; The solution is to reduce the material.
5: when plastic demolding still overheating; the Improved method is molding mould or plastic products immediately soak in cold water, also can extend the cooling time.