First of all, we must understand why the plastic mold has the problem of difficulty in demoulding.
- 1 The groove is formed in the mold;
- 2 The mold release slope is insufficient;
- 3 The mold finish is not high.
The failure caused by insufficient stripping slope is very common.When designing the product, the stripping slope must be marked on the drawing.The stripping slope is usually in the range of 1 ~ 2 degrees, within this range It is better to be as large as possible, and it is allowed to be more than 0.5 degrees in special occasions. 2 If the injection pressure is too high, the product and the mold are too close to each other, it will be difficult to demold. 3 In order to smoothly remove the product from the mold, general use of silicone oil is used. Molding agent, however, only a thin layer can be applied when using a release agent. It is difficult to wipe if the spray is too thick. Also, due to the action of the release agent, secondary processing such as printing marks on the product becomes very bad. Once the release agent applied to the mold is attached to the product, it is quite difficult to wipe it off.
Based on the above root causes, come up with a solution:Instant:
- 1 Decrease injection pressure, shorten holding time, lower mold temperature, reduce demolding speed, spray mold release agent
- 2 Short-term: improve mold cavity finish
- 3 Long-term: increase demolding slope, increase the number of demolding pins . Due to the difference in materials
Heavy and hard materials, such as GPPS, are often damaged due to insufficient de-hatching slope. For materials that are both sticky and soft, such as PE, it is possible for the product to be cut off as a number of roots.