What are the effects of plastic mold deformation?

Plastic mold is an important tool for the production of plastic products. It can give plastic products a complete configuration and accurate dimensions. If the plastic mold is deformed, it will directly affect the quality of plastic products, so we all need to pay attention to plastic mold deformation. So, how do we deal with the deformation of plastic molds?

 

1. In order to reduce the deformation of plastic molds, the heat treatment department should work with the plastic mold design department to improve the design of plastic molds. For example, try to avoid plastic mold structures with widely differing cross-sectional sizes, and try to make the mold shapes symmetrical and complex. Structure, etc.

 

2. When the shape of the plastic mold cannot be changed, in order to reduce the deformation, some other measures can be taken. The overall consideration of these measures is to improve the cooling conditions so that the parts can be uniformly cooled; in addition, various compulsory measures can be supplemented to limit the quenching deformation of the parts.

 

3. The deformation of asymmetric plastic mold is also the result of the combined effect of thermal stress and tissue stress. For example, for thin-walled and thin-edge molds, due to the thin wall of the mold, the internal and external temperature difference during quenching is small, so the thermal stress is small; but the hardening is easy, and the tissue stress is large, so the deformation tends to expand the cavity.

 

4. For symmetrical plastic molds, the deformation tendency can be considered according to the cavity size, outline size and height.

 

When the wall of the plastic mold is thin and the height is small, it is easier to harden, which may be the main role of tissue stress. Therefore, the cavity often tends to swell. Conversely, if the wall thickness and height are large, it is not easy to harden. At this time, thermal stress may play a major role. Therefore, the cavity often tends to shrink.

 

In production practice, we must also consider the specific shape of the part, the steel type and heat treatment process used, and continuously summarize the experience through practice. Because in actual production, the external dimensions of plastic molds are often not the main working dimensions, and after deformation, they can be corrected by grinding.