Abstract: A butterfly valve includes an annular valve seat and a disc-like valve member mounted both for rotation about an axis parallel to the valve seat and for axial displacement relative to the seat. The actuating mechanism automatically effects sequential motion of the valve member, first to rotate it to closed position and to shift it into sealed engagement against the valve seat, and vice versa, and includes structure which self-locks in the latter position.

Abstract: In order to reduce corrosion problems which may be experienced with valves having flange couplings between the housing parts, the present invention provides a valve in which the cover 2 has a part 12 which fits into a corresponding part 11 of the housing 1 and is held therein by an annular spring 15. A sealing ring 17 seals the cover to the housing. Preferably the interlocking parts of the housing and the cover are oval in section to prevent relative rotation of the parts. The avoidance of protruding sharp edges facilitates the provision of a uniform overall protective layer of, for example, tar.

Abstract: Filter press consisting of a frame having a fixed head, with guides for filter plates provided with communicating ducts and having supply and discharge connections and with a loose head having a clamping device for clamping a set of filter plates against the fixed head, wherein a carriage or slide is situated above the filter plates for travel along horizontal guides and is provided with means which can be moved vertically with respect to the carriage or slide to release a plate from the set of plates and establish a coupling with the plate such that the plate is driven when the carriage or slide is moved.