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

A ball valve is provided with a valve case forming an internal space that is centrally extending to opposite inlet and outlet sides. A ball valve element is disposed within the interior space and has

Concerning improvements in a plastic ball valve, the applicant of the present patent application formerly applied for a utility model registration on a construction of the plastic ball valve comprisin

Ball valves are known which substantially comprise a valve body, wherein a seating has been provided for a ball having a diametrical cylindrical passage, the ball being rotatable between an open posit

However, conventional ball valves are obtained by machining cast pieces, or by machining stainless steel blocks. In either case, the machining processes require skilled labor and substantial time peri