The introduction of pressure parameters in the injection molding process
In the injection molding process, to overcome the flow resistance of the molten plastic through the nozzle, gate, and cavity, sufficient pressure must be applied to complete the injection molding. The injection molding machine is mainly composed of two parts, injection and clamping parts. The injection pressure and clamping pressure parameters are important technical details for injection molding. The injection pressure parameter includes injection pressure, clamping pressure, and other action pressure. The specific parameters are as follows:
1. Injection pressure
Injection pressure is the most important injection molding pressure parameter. It plays a decisive role in the flowability of the molten plastic and the filling of the mold cavity. It also has a direct impact on product size accuracy and product quality.
In general, there are one, two, and three levels of injection pressure in common injection molding machine models. In actual production, the appropriate injection pressure needs to be set according to the plastic material and the structure of the molded products.
2. Clamping pressure
Clamping pressure is set from low-pressure clamping, through high-pressure clamping, to the end of clamping. When the clamping action is about to end, to protect the mold and clear the inertial impact, the clamping pressure parameter can be reduced.
3. Holding pressure
The molten plastic in the mold cavity is further compacted. The holding pressure ensures that the mold cavity pressure remains constant until the gate is solidified.
4. Back pressure
Back pressure is generated during the plasticizing process of the plastic material in the barrel. In the front end of the screw tip and the molten plastic, the molten plastic is subjected to pressure when the screw rotates backward, commonly known as plasticizing pressure.
