According to shrinkage and cooling effect. If the workpiece shrinks after being ejected from the mold, the holding time should be increased. If the workpiece is soft after molding, the shape is not good. Also try to increase the holding pressure and cooling time. In the injection molding process, the solution shrinks due to cooling, but due to the screw To continue to move forward slowly, so that the melt in the material tube continues to be injected into the cavity to supplement the need for product shrinkage, which is called pressure retention. To put it plainly, it is to prevent product shrinkage. With pressure retention, product production is relatively stable. .
Holding pressure can also adjust the size of the product without the weld line, dent, flash and warpage.
As you can see from the above, there is a certain reason to keep the mold under pressure during the plastic injection process. In order to improve the quality of the product, some steps have to be done.
