Temperature control of plastic mold processing and injection molding


Temperature control occupies a very important part of p […]

Temperature control occupies a very important part of plastic mold processing and injection molding. It can determine whether the product is good or bad. The bigger picture is that even if you make it to the customer, you will lose the customer’s trust and cause The company’s losses are small, it’s okay to redo it. These are no longer needed, but you have to remember that these are actually a waste of the company’s resources.

1. Cylinder temperature: The temperature that needs to be controlled during the injection molding process includes the cylinder temperature, nozzle temperature and mold temperature. The first two temperatures mainly affect the plasticization and flow of the plastic, while the latter temperature mainly affects the flow and cooling of the plastic. Each plastic has a different flow temperature. For the same plastic, due to different sources or grades, its flow temperature and decomposition temperature are different. This is due to the difference in average molecular weight and molecular weight distribution. Plastics in different types of injection The plasticization process in the machine is also different, so the temperature of the barrel is also different.
2. Nozzle temperature: The nozzle temperature is usually slightly lower than the top temperature of the barrel. This is to prevent the "salivation" that may occur in the straight-through nozzle of the molten material. The temperature of the nozzle should not be too low, otherwise it will cause the premature solidification of the melt and block the nozzle*, or the performance of the product will be affected due to the premature solidification of the material injected into the cavity.
3. Mold temperature: Mold temperature has a great influence on the internal performance and apparent quality of the product. The temperature of the mold depends on the crystallinity of the plastic, the size and structure of the product, performance requirements, and other process conditions (melt temperature, injection speed and injection pressure, molding cycle, etc.).