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How to Solve The Whitening of PET Hot Runner Injection Gate?

Have you encountered the problem of the injection gate turning white during the PET injection molding process? This not only affects the appearance quality of the product, but may also cause difficulties in production. Don't worry, this article will provide you with a detailed introduction to effective methods for dealing with the whitening of PET hot runner adhesive ports.

PET, as a common engineering plastic, has good properties and wide applications. However, during the injection molding process, due to various factors, it is common for the hot runner nozzle to turn white. Firstly, we can solve this problem by rinsing with ice water. PET material is sensitive to temperature, and excessive mold temperature can easily lead to whitening. Using ice water can effectively reduce mold temperature.

Secondly, it is necessary to carefully inspect and optimize the cooling system of the hot runner and mold. ensure good cooling effect near the gate, and a reasonable mold design can provide sufficient cooling around the gate. Adjusting the injection molding process parameters is also a crucial step. Reduce injection pressure, injection time, and dosage appropriately, minimize molecular orientation, and avoid prolonged holding time.

Furthermore, controlling the material temperature is crucial. The material temperature setting during PET injection molding should be just right, usually around 300 degrees, but depending on the specific product, it may need to be adjusted between 275 degrees and 290 degrees. The recommended drying temperature is between 120 ° C and 165 ° C, with a drying time of 4 hours and a humidity requirement of less than 0.02%. In addition, it is necessary to check the condition of the hot nozzle to ensure that the temperature at the head of the hot nozzle is uniform and the insulation is good. Clean the mold to prevent traces of cold material residue.

Finally, improve the mold design, such as using appropriate mold materials, optimizing gate and inlet design, etc. Meanwhile, pay attention to the preservation of raw materials to prevent dust from entering.