Impurity Filtration PE raw materials may be mixed with impurities such as dust, metal shavings, gel particles, etc. during the production process. The screen changer intercepts these impurities through the screen and prevents them from entering the downstream equipment (e.g., molds, melt pumps), thus reducing defects such as surface imperfections, bubbles, and holes in the products. For example, in the production of XPS foam sheet, the screen changer can reduce the content of impurities to less