Knowledge of plastic injection molding process

The basis for setting the speed of the velocity must be taken into account for the geometry of the die, other flow constraints and the instability factors. Speed setting must be a clear understanding of the plastic injection molding process and materials in Dongguan, otherwise, the quality of the products will be difficult to control. Because the melt flow rate is difficult to directly measure, can be determined by measuring the screw forward speed, or the type of cavity pressure indirectly calculated (determine the check valve no leakage).

Material properties are very important, because the polymer may be due to different stresses and degradation, increasing the temperature may lead to severe oxidation and chemical degradation, but at the same time by the degradation of the degradation of shear, because the high temperature reduces the viscosity of the material, reduce the shear stress. No doubt, the multi segment injection molding speed is very helpful to the formation of heat sensitive materials such as POM, UPVC, PC, etc..

The geometry of the mold is also the deciding factor: the thin wall need the maximum injection speed. The thick wall parts need to be slow and fast - slow - speed curve to avoid the defects. In order to guarantee the quality of the parts, the speed of the plastic injection molding process in Dongguan should be guaranteed. Melt flow rate is very important, because it will affects the components of the molecular arrangement direction and surface state; when the melt front reaches cross regional structure, you should slow down; for the radial diffusion of the complex die should be guaranteed to melt through the equilibrium quantity increase; flows must be quickly filled to reduce the cooling of the melt front, but the injection of high viscosity material, such as PC is the exception, because too fast speed will be cold materials through the inlet into the cavity.