The function of the injection system: The injection system is one of the most important components of the injection molding machine. Generally, there are three main forms: plunger type, screw type, and screw preplasticized plunger injection type . The screw type is currently the most widely used. Its function is that in a cycle of the plastic injection machine, a certain amount of plastic can be heated and plasticized within a specified time, and the molten plastic can be injected into the mold cavity through a screw under a certain pressure and speed. After the injection, the molten material injected into the cavity is kept in shape.