In the first step of the process, an injection molding processing system produces a preform. The pet preform for water bottle is then fired into the mold cavity to melt, followed by rapid cooling at a temperature that is below the crystallization temperature range. This creates a transparent preform.
In the second step, the preform is heated to a temperature that is higher than the glass transition temperature. After this step, the preform is extended through blow molding and then cooled.
The Method of Processing
After the one-piece is shot and blown in the same machine is finished, the injection-molded preform is cooled to a temperature range that is below the crystallization temperature range, but it continues to be in a condition of thermo-elasticity before being blown into bottles.
The success of the preform injection molding process is directly correlated to the quality of the plastics used. The requirements for the design must be compatible with the performance of the injection molding machine.