The quality of plastic injection molding begins with the tiny dispute of mold design. As the “molding machine”, the design of the runner system of the mold directly affects the melt filling uniformity. Taking the production of mobile phone middle frame as an example, the mold needs to adopt hot runner technology to keep the melt temperature stable through the built-in heating device, so as to avoid material waste and temperature gradient problems caused by traditional cold runner. At the same time, the surface of the mold cavity needs to be polished at nanometer level, and the roughness should be controlled below Ra0.05¦Ìm, so as to ensure that the surface smoothness of the product can reach the mirror effect and meet the high requirements of high-end electronic products for appearance.in fact plastic injection molding parts It is more and more welcomed by our customers, and its market performance is gradually improving. https://www.tigerbrotherplastic.com/
Dynamic control of process parameters is the key to molding quality. The combination of injection pressure, speed and holding time should be adjusted in real time according to the material characteristics. For example, in the production of highly transparent medical containers, if the injection speed is too fast, the shear heat generated by the friction between the melt and the mold cavity will lead to the degradation of the material, which will lead to the yellowing or embrittlement of the products; However, insufficient holding time will increase the shrinkage of products and decrease the dimensional stability. Modern injection molding machine has been equipped with intelligent control system, which can monitor the parameters such as melt temperature and mold pressure in real time through sensors, and automatically correct the process curve to reduce the rejection rate from 5% of the traditional process to below 0.5%.
The post-processing link can not be ignored either. The products after demoulding often have internal stress, which needs to be eliminated by heat treatment. The product is kept in an oven at 80-120¡æ for 2-4 hours, which can rearrange the molecular chains, reduce the residual stress and prevent cracking in subsequent use. For parts that need surface decoration, such as automobile interior decoration, spraying, electroplating or water transfer printing are used to form metal texture or wood grain texture on the plastic surface to enhance the added value of products.