Huadian pump valve company production and sales of integrated flange stainless steel high temperature ball valve, closing part ball around the valve body center line rotation to achieve open, closed a kind of valve, the seal embedded in the stainless steel valve seat, metal valve seat end is provided with a spring, when the sealing surface is worn or burned, under the action of the spring to push the valve seat and the ball to form a metal seal. It has a unique automatic pressure relief function, when the medium pressure in the valve cavity exceeds the spring preload, the outlet end valve seat retreats away from the ball, to achieve automatic pressure relief effect, the valve seat automatically reset after pressure relief, this series of ball valves are suitable for water, solvents, acid and natural gas and other general working media, but also suitable for working conditions of harsh media, such as oxygen, hydrogen peroxide, methane and ethylene, etc., in various industries have been widely used.