Temperature Control of Plastic Mold Processing and Injection Molding

Temperature control plays an important role in plastic mold processing and injection molding. It can determine whether the quality of the end product is good or bad. If the quality of the product is bad, in the big picture, even if you make it to the customer, you will lose the trust of the customer and cause losses to the company; specifically, it doesn't matter to do it again, but you should remember that these are actually a resource waste of the company.

1. Temperature of melt cylinder: the temperature of the melt cylinder, nozzle, mold, etc. should be controlled during the plastic injection process. The temperature of the first two parts mainly affect the plasticization and flow of plastics, while the temperature of the latter one mainly affects the flow and cooling of plastics. Each kind of plastic has different flow temperature. As to the same kind of plastic, because of different sources or brands, the flow temperature and decomposition temperature of them are different. This is due to the differences of average molecular weight and molecular weight distribution. Besides, the plasticizing process of plastics in different types of injection molding machines are also different, so the selection of temperature for the feed cylinder is also different.

2. Temperature of nozzle: the temperature of nozzle is usually slightly lower than that of the top of the cylinder, which is to prevent the " sialorrhea" of melt flow that may occur in the direct nozzle. The temperature of the nozzle should not be too low, otherwise the nozzle will be blocked by the melt flow caused by the early condensation of the melt, or the performance of the product will be affected due to the injection of the early condensed melt into the mold cavity.

3. Temperature of mold: the temperature of the mold has great influence on the internal performance and apparent mass of products. The temperature of the mold is determined by the crystallinity of the plastic, the size and structure of the product, performance requirements, and other process conditions (melting temperature, injection speed and injection pressure, molding cycle, etc.).