The working principle of blow molding machine

Blow molding machines are mainly divided into three categories: extrusion blow molding machines, injection blow molding machines and special structure blow molding machines. The processing technology is mainly divided into one-step method and two-step method. One-step and two-step blow molding machine molding process, mainly used for PET and BOPP hollow container molding. Both have their own characteristics and are widely used. In comparison, the two-step method is more suitable for the centralized production of preforms and dispersed blown bottles; while the one-step method is more suitable for the online production of beverage companies.

The blowing procedure of the blow molding machine mainly has 6 steps:

1) First put the heated plastic embryo into the mold;

2) Use the clamping cylinder to tighten the mold;

3) Then use high pressure or mechanical structure to lock the embryo mold;

4) Medium and high pressure pre-blowing, while stretching the cylinder action to expand the blank mold;

5) High-pressure air blowing, the preform is shaped according to the mold, and the pressure is maintained for a certain period of time;

6) Release the high pressure in the formed bottle and reset the cylinder—take the bottle.

Pneumatic equipment is used in many places during the operation of the blow molding machine; from unloading - locking - stretching - high pressure blowing \ deflation - taking bottles, this series of actions are all assisted by pneumatic equipment. For example, stretching the high-pressure air blowing and deflation circuit, the air circuit is divided into two parts, the normal pressure part and the high pressure part.