Abstract: A piston slide valve including a valve housing, a piston slide mounted movably in the valve housing, which is reciprocally movable in the valve housing and configured to manipulate a fluid flow, and a valve drive. The valve drive includes a rotatable drive shaft, which is mechanically connected to the piston slide via a mechanical coupling. The mechanical coupling includes an actuating element which is eccentrically mounted on the rotatable drive shaft and which engages with a coupling piece that is attached to a radial outside of the piston slide, wherein either the actuating element has a spherical outer surface, which engages into said cylindrical opening of said coupling piece, or the coupling piece has an outer surface, which engages into a cylindrical opening of the actuating element.

Abstract: A piston slide valve including a valve housing, a piston slide mounted movably in the valve housing, which is reciprocally movable in the valve housing and configured to manipulate a fluid flow, and a valve drive. The valve drive includes a rotatable drive shaft, which is mechanically connected to the piston slide via a mechanical coupling. The mechanical coupling includes an actuating element which is eccentrically mounted on the rotatable drive shaft and which engages with a coupling piece that is attached to a radial outside of the piston slide, wherein either the actuating element has a spherical outer surface, which engages into said cylindrical opening of said coupling piece, or the coupling piece has an outer surface, which engages into a cylindrical opening of the actuating element.

Abstract: A twin-wire former for a paper machine having two endless loop wires, a wire support frame and a head box. The web forming zone leading from the entrance slot, which is at the breast roll in one wire loop and the forming roll in the other wire loop, is inclined at an angle of 30.degree. to 50.degree. to the horizontal. The wire support frame has the shape of an inverted U with a front support arranged upstream of the head box, a rear support arranged downstream of the headbox and an upper beam which connects the upper ends of the front and rear supports to each other. A lower beam is located within the loop of the lower wire and extends to both of the forward and rearward sides of the rear support with one end extending into the U-shaped frame while the other end extends at least approximately up to the remote end of the loop of the lower wire. At least one water removal element of the upper wire is suspended from the upper beam. At least one water removal element of the lower wire rests on the lower beam.

Abstract: The invention relates to a method of operation of a pump-turbine between part-load and reverse pumping operation in which the various operating conditions are produced by changing the position of the wicket gates in that some of the wicket gates are removed from the synchronous operation as provided by the mechanical gate ring operator and inserting a servo-motor between the wicket gate and the gate ring which functions to alter the connection between the selected wicket gates and the gate ring operator.