Although the guidelines for the molding shrinkage ratios of typical plastic resins were explained in the last lesson, we would like to add some more information. This time, we provide the values for some engineering plastics resins.

The table shows the major thermoplastic resins and their molding shrinkage ratios, cavity surface temperatures, and injection molding pressures. For more details, it is common to obtain the material catalogs or technical documents for each material grade from the manufacturer of the material, and to use them as the documents for making decisions.

* The values given here are for natural resins unless otherwise stated.

Table of molding shrinkage ratios of major plastic resins (2)