Ball valves and is especially advantageous in ball valves in which the valve ball "floats" in the sense that it is subject to displacement by the force of differential fluid pressure on the ball. The

Ball valves are already known in the prior art. The known ball valves comprise of valve body, a stem, a ball, seats, a pair of seat carriers, connecting sleeves and union nuts. The valve body has a cy

According to one aspect of the present invention, in an upstream fluid passageway of a valve housing there is fitted a valve seat retainer movable forwardly and backwardly within a given distance alon

The present invention makes it possible to fix the ball carrier to the valve body without hindering insertion of the ball, by providing projections on the inner wall surface of the valve body. In part

In prior known ball valves, the valving means firmly engages valve seats at both the inlet and outlet ports and is in pressure contact therewith. Accordingly, relatively high torques are required for

Ball valves have a small space requirement for a given flow cross-section and are therefore widely used in particular in mobile equipment. Thus, ball valves are widespread as shutoff members in fire-f

This rotatable ball valve provides a quick cutoff means without producing a locked-up system downstream of the valve. Thus, downstream moving parts, such as pistons, may be freely relocated. The valve

In the case of ball valves of the generic type provided with a one-piece housing, the ball is inserted into the housing via a fluid opening. In order to be able to rotate the ball accommodated in the