On the premise of ensuring that the injection molded parts are not deformed, the cooling time is shortened as much as possible, so that the PP modified plastic injection molded parts can be ejected in advance at high temperature. At this time, the temperature of the outer layer of injection molded parts is still very high, and the skin is not too hardened, so the temperature difference between inside and outside is relatively small, which is beneficial to the overall shrinkage, thus reducing the centralized shrinkage inside injection molded parts.

Because the overall shrinkage of injection molded parts is constant, the more the overall shrinkage, the smaller the centralized shrinkage, and the lower the degree of internal shrinkage and surface shrinkage.

Extended data:

Precautions:

1. Whether the operators are familiar with the product quality standards before operation.

2. The injection molding factory indicated that the processing method should be correct. For example, the nozzle position must be cut flat or batch flat, and other edges cannot be cut or cut.

3. Pay attention to shrinkage, color mixing, top height, lack of glue, material flower, etc. When testing the appearance, it is necessary to make clear the limit acceptance.

4. Products with strict appearance requirements, such as mirrors, light buttons and smooth surfaces. Externally assembled and not sprayed with oil, there shall be no fingerprints and oil stains. The workbench should be kept clean, and the products should not be scratched and worn.

5. In the production process, conduct a comprehensive inspection of the products every 30 minutes, carefully check the samples and quality inspection package instructions, and ensure that the qualified rate of the produced products reaches 100%.

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