Common problems and solutions for PET preforms injection molding machine, Part 3.

6, Air bubbles in the PET preforms.

A, Causes:

   1, PET granules are not dried enough.

B, Solutions:

   1, Enhance the drying process

   2, Increase the material temperature

   3, Slow down the rotary screw

7, Irregular ring groove in the PET preforms.

A, Causes:

   1, Condensate water inside the preforms molds.

B, Solutions:

   1, Dry the factory workshop

   2, Increase the temperature of the cooling water

   3, Wipe dry the internal and external parts of the injection molds.

8, Cracks on the injection position of the preforms.

A, Causes:

   1, The hot runner is not straight with the injection nozzle.

   2, Material back to the injection nozzle

   3, Injector area is too hot

B, Solutions:

   1, Fix and repair the molds

   2, Fix and repair the injection nozzle

   3, Increase the cooling time