Introduciton of injection moulding machine working process and principle
injection molding machine is one of the most important plastic processing machinery.It can seperated into two types of machines, horizontal and vertical machine.
According to the different clamping unit structure of horizontal injection moulding machine, it can separated into traditional toggle link system injection machine and direct pressure clamp injection machine.
Below is the working process and principle of direct pressure type injection molding machine, but it also similar to toggle type machine.
- Machine standby
- mold close and clamp , the moving mold platen quickly approaching to the fixed mold platen (quick-slow-quick), and make sure there isn’t any foreign matter in the mold area,mold closed with high pressure.
- injection carriage moving forward and machine’s nozzle touch the main sprue of mold.
- machine do the injection, push the melt material from the barrel into the mold cavity.
- Cooling and pressure holding, you can set the holding pressure and time while the mold cavity is cooling
- charge. the product inside the mold cavity is still under cooling.the hydraulic motor driving the screw and push the melt material forward. the screw will backward under the set back-pressure. when the screw backward to the set position, hydraulic motor stop working and charge finished.
- injection carriage backward moving. Generally, for the injection carriage backward is canceled during the production.
- mold open. moving mold platen moving to the set position. (slow-quick-slow)
- ejection. the machine eject out the product
- mold closing and continue the next cycle.
Above is the common working process of injection molding machine. See below schematic diagram of injection moulding machine working process. (it may be different according to different product and machine)