Effect of injection molding thickness on shrinkage change
The processing of injection molds is a very complex and dynamic processing process. Each factor of the molding process has an important impact on the molding quality of the product, and molding shrinkage is one of the key factors affecting the quality of the product.
There are many factors that affect the shrinkage of injection molds, molding materials (including the molecular chain structure, crystallinity, mechanical properties, rheological properties of polymers, etc.), product structure (including product thickness, insert structure, etc.), process conditions (including injection Speed, holding pressure, holding time, cooling time, etc.) and mold design (including gate location and number, cooling circuit distribution, etc.) all affect its shrinkage behavior.
Whether it is a crystalline plastic or an amorphous plastic product, when the thickness of the product is different, the shrinkage of the product is very different. As the thickness of the product increases, the longitudinal shrinkage and lateral shrinkage of the product are increasing. Big. The injection mold gradually slows down as the thickness increases, and the longitudinal shrinkage is slightly smaller than the transverse shrinkage.