The working principle of the injection molding machine is similar to the syringe used for injection . It uses the thrust of the screw (or plunger) to inject the plasticized plastic in the molten state (that is, the viscous fluid state) into the closed mold cavity. The process of obtaining products after curing and shaping. Injection molding is a cyclic process, each cycle mainly includes: quantitative feeding - melting plasticization - pressure injection - mold filling and cooling - mold opening and taking parts. After taking out the plastic part, the mold is closed again for the next cycle.