Steel wire is the most commonly used metal filter information of extruder. Although stainless steel is more expensive, it can prevent rusting. Nickel alloy filter screen is used to prevent corrosion by fluoropolymer or PVDC. Generally, the mesh size of the filter screen (or the number of wires per inch) is 20-150 or more. The mesh size of 20 mesh is relatively coarse; that of 40-60 mesh is fine; and that of 80-150 mesh is very precise.

The mesh of most metal filters is square woven, with the same number of wires in each direction. Dutch weaving method is to select coarse wire in horizontal direction, and the number is even. The filter screen made by Dutch weaving method can achieve precise filtering effect without setting parallel screens in the filtering equipment.