When the plastic enters the mold and begins to cool, the molecules begin to return to the desired equilibrium state, and shrinkage begins to occur. The distance between molecules will be higher in the melting state than in the cooling state. With the continuous cooling of the solution, the intermolecular spacing will continue to decrease, resulting in a decrease in the overall volume of the plastic, which will directly lead to shrinkage

Shrinkage should be one of the most common problems of injection molded parts Machining and injection molding manufacturers It is believed that people engaged in injection molding have their own methods and experience on how to deal with the shrinkage problem of injection molding parts. However, few people have explored the causes of shrinkage from the perspective of polymer characteristics

The larger the volume of the plastic increases during the melting period, the greater the shrinkage during its cooling period. The shrinkage of plastics during injection molding is easily affected by various molding parameters. This is a huge challenge for in mold injection molding manufacturers to determine the size of mold steel and mold steel. Therefore, the key is to develop a stable injection molding process, which can continue to produce parts with uniform shrinkage and quality