The molded part refers to the various parts that make up the shape of the product, including the dynamic mode, the mold and the cavity, the core, the forming rod and the exhaust port. The molded part consists of a core and a concave die. The core forms the inner surface of the product, and the concave mold forms the outer surface shape of the product. The die cavity is formed by the mold core and cavity after the mold is closed. According to the process and manufacturing requirements, sometimes the core and die by a number of pieces of the combination, sometimes made into a whole, only in the easily damaged, difficult parts of the use of inserts.