What are the main injection molding processes and principles?

The injection molding process is mainly done on the injection molding machine. The main injection molding process includes plasticizing measurement, injection molding, pressure holding, cooling and other processes. The study of injection molding process is to adjust injection molding process parameters according to plastics and products, and control the quality of injection molding products.

1.Plasticizing metering process

Plasticization refers to the process in which the plastic is heated in the barrel to reach a flowing state and has good plasticity, ready for injection into the mold. The plastic melt should reach the specified molding temperature when entering the cavity, and can provide a sufficient amount of molten plastic within the specified time, and the temperature of the molten plastic should be uniform at all points, and no or very little thermal decomposition occurs to ensure the continuous production.
The plasticizing process of plastic in the cylinder is that the solid particle or powder is heated, compacted, mixed, and transferred from the glass state. The process of converging to a homogeneous viscous flow state.

2. Injection mold filling and pressure retaining process

The process of injection molding is the process of injecting the plasticized melt in the measuring chamber into the mold cavity. The injection molding is divided into two stages: the injection stage and the pressure holding stage. The injection stage starts from the screw advancing melt until the melt fills the cavity. The pressure holding stage starts from the melt filling cavity to the gate "freezing". The pressure holding stage can be divided into the pressure holding replenishment flow stage and the pressure holding switching reverse flow stage.

3. Cooling and setting process

The cooling setting process starts from the gate "freezing" to the product demudding, and the temperature performance is the main factor in the cooling setting process
Yes. Generally, from the gate "freezing" to the product release, it is still necessary to continue cooling in the cavity for a period of time to ensure that the product has enough stiffness without distortion. During this process, the melt temperature in the cavity decreased gradually.