Mold designers must have a wealth of design and injection molding experience, you must consider the relationship between these factors and injection molding conditions and its apparent factors, such as injection pressure and cavity pressure and filling speed, injection melt temperature and mold temperature, mold Structure and gate form and distribution, as well as the gate cross-sectional area, product wall thickness, reinforced plastic filler content, plastic material crystallinity and orientation and other factors. The above factors also vary depending on the plastic material, or other molding conditions such as temperature and humidity, continuous crystallization, and changes in the injection molding machine after molding.