The ball of the ball valve is floating, under the action of medium pressure, the ball can produce a certain displacement and tightly pressed on the sealing surface of the outlet end, to ensure the sealing of the outlet end. Floating ball valve structure is simple, good sealing, but the ball to withstand the load of the working medium all transferred to the outlet seal ring, so we should consider whether the seal ring material can withstand the working load of the ball medium or not, in the case of a higher pressure impact, the ball may be deflected.