PP open mold injection molding process should pay attention to the problem (including the requirements of injection molding machine) in order to reduce internal stress and surface quality defects, PP open mold injection processing should pay attention to the following aspects.
Should use special screw, abs open injection molding with separate temperature control nozzle.
The injection temperature should be higher than the plastic resin without decomposition.
PP open mold injection processing injection pressure: Generally higher, to overcome the drawback of high viscosity of the melt, but too high pressure will cause internal stress and cause deformation and deformation
Injection speed: In the case of filling the mold, it is generally preferred to use a slow, fast and slow multi-stage injection;
Holding time and molding cycle: In the case of satisfying the filling of the product without generating depressions or bubbles; Should be as short as possible to minimize the residence time of the melt in the barrel
Screw speed and back pressure: Under the premise of satisfying the quality of plasticization, it should be as low as possible to prevent the possibility of depreciation.
PP open mold injection molding mold temperature: The cooling of the product is very good and has a great influence on the quality. Therefore, the mold temperature must be able to accurately control the process. If possible, the mold temperature should be higher.