What problems should be paid attention to when PS plastic mold injection processing?

2020-12-07 21:30:38

a. PS material is an amorphous plastic, which has low moisture absorption and is not easy to be decomposed, but it is prone to brittle fracture, large thermal expansion coefficient, and internal stress.

b. PS plastic has good fluidity, so it is better to use screw or plunger injection machine for injection molding. The nozzle is straight-through or self-locking, but it is necessary to prevent flash.

c. High material temperature, high mold temperature, and low pressure injection pressure should be used for PS plastic mold injection processing. Prolonging the injection time will help reduce internal stress and prevent shrinkage and deformation (especially for thick-walled plastic parts). If the material temperature is too high, “silver wire” is easy to appear. If the material temperature is too low or too much release agent, the transparency will deteriorate.

d. PS plastic molds can use various types of gates. The gate and the plastic part should be connected in an arc to prevent the plastic part from being removed when the gate is removed. The demolding angle of PS plastic mold should be larger. The ejection should be uniform to prevent cracking and deformation due to poor demolding.

e. The wall thickness of the plastic parts should be uniform, without inserts (if there are inserts, it should be preheated). All sides should be connected by arcs, and no gaps or sharp corners should be present.