Since the material of each product is different, it often leads to defective products during injection molding. For example, rigid plastic products often appear shock lines, so what is the reason? Is there a good solution?
The cause of the vibration of the product in injection molding
Rigid plastic parts such as PS form dense ripples centered on the gate on the surface near their gates, sometimes called shock lines. The reason is that when the melt viscosity is too large and the mold is filled in the form of stagnant flow, the material at the front end will quickly condense and shrink as soon as it touches the surface of the cavity, and the subsequent melt will expand the contracted cold material and continue to move forward The continuous alternation of the material flow forms surface shock lines in the progress.
Solutions for product vibration lines in injection molding:
(1) Increase the barrel temperature, especially the nozzle temperature, and also increase the mold temperature.
(2) Increase the injection pressure and speed to make it quickly fill the model cavity.
(3) Improve the size of the runner and gate to prevent excessive resistance.
(4) The mold exhaust should be good, and a sufficiently large cold material well should be set.
(5) The parts should not be designed too thin.
