Core pin is a general term for parts used to process the inner surface of molded plastic products. It is usually used to shape the inner hole or cylindrical shape of the product. The choice of core pin is mainly based on the shape of the molded product to specify the shaft diameter, overall length, and step shape. If necessary, it is necessary to process the shape of the tip and the shape of the shoulder. Sometimes in order to facilitate the exhaust of the slender structure of the formed product (such as ribs, cylinders, etc.), core pins are also used.