Principle of Injection Molding

During injection molding, the dynamic mold and the fixed mold are closed, the plastic particles are dried and poured into the hopper of the injection molding machine. The push rod (screw) of the injection molding machine pushes the particles forward, and the molten material is heated and melted into a non-Newtonian fluid with a heating coil in the cylinder during the push rod. The particles are pushed to the nozzle position when the fluid is already at high temperature. The molten material is injected into the mold system through the nozzle into high pressure fluid, and is filled into the mold cavity through the main channel, runner and gate. After filling, the injection is stopped and the pressure is maintained. Then the cooling system starts to operate (there is cooling water flowing in the template), the mold is opened, the ejecting system moves to ejection the product, and finally the product is removed (manually or by mechanical arm). And so on. A typical cycle is no more than 1 minute.