Hard sealed floating ball valve seals flexible single-slope or V-groove design of a flexible ring structure, when the medium pressure is too small, the sealing contact with the ball smaller and therefore have a greater sealing pressure to ensure reliable sealing, medium pressure, the ring and ball contact area increases, it can be affected by the larger ring of thrust and will not damage media. Fourth, because of poly ethylene, such as sealing material has good self-lubrication, and friction loss and the sphere of small, so the long-ball valve.