The ball of the floating ball valve is floating. Under the action of the medium pressure, the ball can produce a certain displacement along the axis of the ball and press tightly on the valve seat sealing ring at the outlet end to ensure that the outlet end is sealed, but the inlet end cannot be sealed. The floating ball valve is a single-sided forced sealing form.
The ball of the fixed ball valve is fixed by the lower stem and will not move after being pressed. Therefore, the two sealing rings must have sufficient pre-tightening force to ensure the sealing of the valve seat and the ball during the design. It is a double-sided forced seal. Thrust or sliding bearings are usually installed on the upper and lower stems that are connected to the ball.
