What are the types of pressure control in injection molding?
The pressure in injection molding includes four types: plasticizing pressure, injection pressure, holding pressure, and cooling pressure. These four pressures directly affect the plasticization of plastic and the quality of products.
1. Plasticizing pressure
Plasticizing pressure is the pressure applied to the molted material by the screw during plasticizing. It directly affects the plasticizing effect of plastics. Excessive plasticizing pressure will cause plastics to overheat and deform, and insufficient plasticizing pressure will cause incomplete plasticizing, affecting product quality. Plasticizing pressure can be adjusted by the safety valve in the hydraulic system.
2. Injection pressure
Injection pressure is the pressure applied to the molten material by the injection molding machine, it directly affects the filling effect of the products. Excessive injection pressure will cause product deformation, and insufficient injection pressure will cause poor product filling, affecting the appearance and dimensions accuracy of the product. Injection pressure can be adjusted by the pressure control system of the injection molding machine.
3. Holding pressure
Holding pressure is the pressure applied to the product by the injection molding machine after injection. It can prevent the product from shrinking and deforming during cooling. Holding pressure can be adjusted by the holding pressure control system of the injection molding machine.
4. Cooling pressure
Cooling pressure is the pressure applied to the product by the injection molding machine during cooling. Cooling pressure can be adjusted by the cooling pressure system of the injection molding machine.
Pressure control in injection molding is an important factor affecting product quality, it needs to be adjusted according to the process parameter of the product and the requirements of the product.
