The valve offers the significant advantages such as easy switching, reliable sealing, good elastic memory and long service life. Featured by the adoption of full bore, non-rising stem operation, flange bolt connection, and flat-bottom valve seat, it ensures that no impurities are precipitated. The valve is widely used in fluid pipelines of the tap water, sewage, construction, petroleum, chemicals, foods, medicine, light textiles, electricity, ships, metallurgy, energy systems, and other areas as a regulating and intercepting device.