Tips for improving the heat resistance of preforms
1. Cooling time control of preform injection
Strictly control the cooling time of preform injection, so that the preform can be demolded as soon as possible. This can shorten the molding cycle and increase the yield, and can induce spherical crystallization due to the higher residual temperature.
2. Choose a reasonable design of preform and bottle
The optimized preform shape design and bottle mold design help to improve the wall thickness distribution of the bottle and avoid distortion or shrinkage deformation in different regions of the bottle body.
3. Strictly control injection and billet drawing
The parameters of the blowing process and the temperature distribution of each area can avoid the deformation of the preform caused by the release of residual stress at the PET glass transition temperature.