1. The shrinkage coefficient of each material is different, and the plastic mold must have a reasonable shrinkage rate.

2. The plastic mold must have sufficient rigidity, otherwise the mold will be deformed when the mold is closed and pressurized, resulting in "flashing".

3. If the product is ejected when the mold is opened, the ejector page of the injection molding machine can be set (but some injection molding machines do not have this function).

4. Choose a reasonable demolding method, select a reasonable position and number of ejectors, and ensure that the product is not damaged during the ejection process.

5. The cooling (waterway) in the plastic mold is related to the size, shape, plastic performance, holding time and other factors of the product.

6. The plastic mold should choose a reasonable exhaust position and its quantity control. Otherwise, the injection molding is unqualified, and the product will be "out of material".

7. The fixing method of plastic mold and injection molding machine should be reasonable, reliable and firm to prevent accidents caused by displacement when clamping. It should also be easy to disassemble.

8. The plastic mold moves with the injection molding machine together with the moving mold part, without the return spring, and the ejector plate of the mold is connected with the ejector rod of the machine (commonly known as strong ejection).

9. The injection path should be reasonably selected so that the material can reach all places evenly (the flow channel is equal), and there must be enough storage to ensure that the plastic is reconstituted during the shrinkage process.

10. Plastic mold materials do not need post-treatment, because: the plastic is soft, does not need hardness and other special requirements, the heat treatment process may cause mold deformation.

11. The roughness in the cavity of the plastic mold must reach the "mirror level", otherwise it is difficult for the product to be demolded, and the product will be damaged due to excessive force when ejected. The roughness of parts such as dowel pins and mold surfaces are specified by standards.