Fine filter is abbreviated as filter, which is made of metal wire mesh with different meshes. Its function is to filter the molten material flow and increase the resistance of the material flow, so as to filter out mechanical impurities and improve the effect of mixing or plasticizing. With acid resistance, alkali resistance, temperature resistance, wear resistance and other properties; mainly used in mining, petroleum, chemical, food, medicine, machinery manufacturing and other industries. Filters are divided into textile fiber filters and metal filters. The machine installed with a filter is called a filter, which is used to filter natural water and food.