How to choose the appropriate blow pressure during blow molding?

- Jul 06, 2017 -

Blow plastic products factory in the production of blow molding products will control the pressure of blown air. Too low, can not make products close to the mold cavity, the surface of the product can not get a clear text, patterns, but also reduce the product cooling efficiency; too high, it will break the parison.

Because blown air pressure depends on the plastic properties, parison temperature, mold temperature, parison wall thickness, blow ratio and product shape and size and other factors. Low melt maturity, lower cooling rate of plastic, can be used lower blow air pressure. When the product volume is large, the parison blows take a long time, and its temperature is reduced greatly, so it requires a higher blow air pressure.

When the product wall thickness is large, the blown air pressure can be lower, because the larger wall thickness of the parison cooling is slower, in the lower Han degrees under a longer time.