1. Mold size accuracy

The accuracy of mold size should be appropriate, and the design, production, and molding process of the mold should be considered based on the drawings. The key is how to ensure that the actual mold size obtained is within the size tolerance range required by the drawings, which is also a problem that designers need to solve, otherwise it will affect the mold.

2. Shrinkage rate

Even for the same resin, if the molding conditions are different, its shrinkage rate will also be different. When forming a mold, it is required to have a small shrinkage change rate, and the expected shrinkage rate should be as similar as the actual shrinkage rate as possible. However, it is generally difficult to achieve this in the actual process, and the mold needs to be corrected after the mold test.

Prevent forming deformation

The deformation of plastic molds is mainly caused by uneven shrinkage and internal stress in the mold. Therefore, we can take preventive measures as follows:

(1) The number of gates should be appropriate, and each gate should be balanced;

(2) Choosing the correct gate shape and position can be seen based on the mold shape.

3. Prevent deformation caused by demolding

If the shrinkage rate of the material is relatively small, it should be noted that when the forming pressure is high, the plastic part is easy to stay in the mold cavity. In addition, during mold design, demolding should be carried out without deformation of the plastic parts to prevent deformation.