https://www.mstnland.com/products/cast-iron-filter/ Cast iron filter is an indispensable device on the pipeline of conveying medium. It is usually installed at the inlet end of pressure reducing valve, pressure relief valve, positioning valve or other equipment to eliminate impurities in the medium and protect the normal operation of valves and equipment and reduce equipment maintenance costs. Cast iron filters are widely used in metallurgy, chemical industry, petroleum, papermaking, medicine, food, mining, electric power, urban, household and other gas fields.