1. Basic information: PMMA Case, shrinkage

2. Description: Using a injection machine with a clamping force of 70 tons (screw diameter of 32 mm, maximum injection amount of 115 g: GP-PS), whether a molded part with a weight of 179.6 g and a thickness of 17 mm can be molded is tested. do. The main problems are as follows: (1) The amount of injection is not enough. In order to solve this problem, we try to solve it by Flow Molding+ injection molding. (2) The molded part has a thickness of 17 mm, and it can be tested if it can avoid shrinkage at the corner of the product.

If only the corners are considered, the thickness varies greatly. As a result, there is a slight decrease in the inside. The method of how to eliminate the shrinkage of this part was verified. as the picture shows.

3. Improvement process: Using the general molding method, the shrinkage of the corner thickness of 17mm cannot be solved. Therefore, the method of using Heat&Cool (mould temperature 120~85 degrees) has been solved. C/T is 6 minutes. The hot and cold control program at this time is very important.