Home > News > Content

Working Principle

May 26, 2017

The working principle of the injection molding machine is similar to the injector syringe, it is the thrust of the screw (or plunger), the plastic injection of the melted state (i.e. viscous flow state) into the closed mold cavity, and the process of obtaining the products after solidification and shaping.

Injection molding is a cycle of the process, each cycle mainly include: quantitative feeding-melt plasticizing-pressure injection-mold cooling-Starting mold pickup. Remove the plastic and then close the mold, the next cycle.

Injection Molding Machine Operation project: Injection molding machine operation includes control keyboard operation, electrical control system operation and hydraulic system operation three aspects. respectively, the injection process action, feeding action, injection pressure, injection speed, the selection of the top out type, the temperature of the barrel of the monitoring, injection pressure and backpressure pressure adjustment.

General Screw Injection Molding machine Molding process is: first, the granular or powdered plastic into the barrel, and through the rotation of the screw and the outer wall of the barrel heating to make the plastic melting state, and then the machine to mold and injection seat forward, so that the nozzle close to the mold gate, and then to the injection cylinder into the pressure oil, the screw is pushed forward so that the molten material is injected into a closed die with a high pressure and a faster speed, and after a certain time and pressure is maintained (also called holding pressure), cooled, and solidified, can open the mold to remove the product (the purpose of holding pressure is to prevent the mold cavity in the reverse flow, to the mold cavity to replenish the material, as well as to ensure that the product has a certain density and size tolerances). The basic requirement of injection molding is plasticizing, injection and moulding. Plasticizing is the prerequisite to realize and ensure the quality of molded products, and to meet the requirements of molding, injection must ensure sufficient pressure and speed. At the same time, because of the high injection pressure, the corresponding high pressure in the mold cavity (the average pressure in the mold cavity is generally between the 20 45mpa), so it must have a large enough clamping force. Thus, the injection device and the clamping device are the key components of the injection molding machine.