Y strainer is also called Y filter. It is an indispensable filtering device in the pipeline system for conveying the medium. Y strainer is usually installed at the inlet of a pressure reducing valve, a pressure relief valve or other equipment to remove impurities in the medium and protect the normal use of valves and equipments. The Y strainer (water filter) has the advantages of simple production, convenient installation and cleaning, and large dirt holding capacity. As an indispensable high-efficiency filtration equipment in the purification equipment engineering, Y strainer has played a great role in the treatment of domestic wastewater, sewage and industrial sewage; it has effectively processed a large number of domestic and industrial applications in various industries. Sewage has effectively reused precious water resources.