Why is the outer surface of the produced plastic pipe rough?

Adjust the process temperature and reduce the cooling water temperature. The optimal cooling water temperature for the pipe is 20-25°C. Check the water circuit for any blockages or insufficient water pressure, and inspect the heating coils of the barrel and die head for any damage. Adjust the water flow rate into the sizing sleeve. Check the properties and batch number of the raw material. Inspect the temperature of the mold core. If it is higher than the temperature of the die zone, reduce the core temperature. Clean any accumulated material in the mold.