Reasons: The surface of plastic parts miss the correct cooling time.

Solutions:

1, Increase the injection rate;

2, Increase the internal pressure (secondary pressure);

3, Reduce the curing temperature;

4, Increase the injection flow;

5, Increase the injection rate;

6, Extend the injection time;

7, Make the mold temperature uniform;

8, Change the gate position;

9, Expand the gate;

10, Shorten the runner.