A servo valve assembly includes a housing defining a cylindrical cavity having a central axis, and a spool disposed in the cavity and co-axially aligned with the central axis. A pair of transition portions define opposing conical cavity surfaces each connect a respective one of first and second cylindrical cavity portions with a third cylindrical cavity portion. The spool comprises a pair of blocking members projecting radially, and each of the blocking members defines a conical blocking surface opposing a respective one of the conical cavity surfaces to define a fluid flow passage therebetween. A cone angle of each conical blocking surface relative to the central is equal to a cone angle of the opposing conical cavity surface relative to the central axis. The spool is moveable along the central axis to vary a flow area of the flow passages between the conical blocking surfaces and the conical cavity surfaces.

In a flow path switching valve, when a valve rod is shifted toward a first back pressure chamber, a first valve chamber is separated from the first back pressure chamber by a first valve element, and a second valve chamber is separated from an intermediate chamber by a second valve element. When the valve rod is shifted toward a second back pressure chamber, the first valve chamber is separated from the intermediate chamber by the first valve element, and the second valve chamber is separated from the second back pressure chamber by the second valve element. The valve rod has a pressure equalizing path through which the first back pressure chamber and the second back pressure chamber are connected.

In a flow path switching valve, when a valve rod is shifted toward a first back pressure chamber, a first valve chamber is separated from the first back pressure chamber by a first valve element, and a second valve chamber is separated from an intermediate chamber by a second valve element. When the valve rod is shifted toward a second back pressure chamber, the first valve chamber is separated from the intermediate chamber by the first valve element, and the second valve chamber is separated from the second back pressure chamber by the second valve element. The valve rod has a pressure equalizing path through which the first back pressure chamber and the second back pressure chamber are connected.

To improve the switching characteristics of a sanitary switchover valve (1) it is suggested that a valve piston (6) of the switchover valve (1) is designed in such a way that a fluid which flows in through a valve inlet (3) of the switchover valve (1) into a valve body (2) of the switchover valve (1), both in a first switching position (7) and in a second switching position (8) can flow around a connecting element (12), which forms a middle section of the valve piston (6), on all sides. To this end, it is envisaged that an outer diameter (15) of the connecting element (12) is smaller than an outer diameter (17) of a second end section (14) of the valve piston (6), where the second end section (14) is arranged in the region of a second valve outlet (5) of the valve body 2.

To improve the switching characteristics of a sanitary switchover valve (1) it is suggested that a valve piston (6) of the switchover valve (1) is designed in such a way that a fluid which flows in through a valve inlet (3) of the switchover valve (1) into a valve body (2) of the switchover valve (1), both in a first switching position (7) and in a second switching position (8) can flow around a connecting element (12), which forms a middle section of the valve piston (6), on all sides. To this end, it is envisaged that an outer diameter (15) of the connecting element (12) is smaller than an outer diameter (17) of a second end section (14) of the valve piston (6), where the second end section (14) is arranged in the region of a second valve outlet (5) of the valve body 2.

A controller assembly comprises an electromechanical actuator and a single-stage pneumatic flow switch configured to thermally protect the electromechanical actuator by a supply of cooling fluid. The single-stage pneumatic flow switch is movable between a first mode in which the switch is configured to open a cooling fluid flow passage and a second mode in which the switch is configured to close the cooling fluid flow passage. The electromechanical actuator is coupled to a valve movable between an open and a closed configuration.

An inventive lock open device for use with a poppet type check valve is disclosed. The device permits bidirectional flow of fluid or gas by defeating the check valve sealing device which permits hydrostatic testing without the need for check valve disassembly or the need for additional tooling.

A plug valve including a valve body defining an internal cavity, a first passage, and a second passage, a plug defining a third passage and being rotatable within the internal cavity, and an insert extending within the internal cavity between the valve body and the plug. The insert defines an interior surface and an opening aligned with the first passage of the valve body. The insert may also define a sealing surface extending around the opening and standing in relief against the interior surface to sealingly engage the plug. In addition to, or instead of, the sealing surface, the insert may define a projection at least partially defining the interior surface. In addition, a boot may be connected to the valve body and interlocked with the projection to prevent, or at least reduce, rotation of the insert relative to the valve body when the plug rotates within the internal cavity.

A plug valve including a valve body defining an internal cavity, a first passage, and a second passage, a plug defining a third passage and being rotatable within the internal cavity, and an insert extending within the internal cavity between the valve body and the plug. The insert defines an interior surface and an opening aligned with the first passage of the valve body. The insert may also define a sealing surface extending around the opening and standing in relief against the interior surface to sealingly engage the plug. In addition to, or instead of, the sealing surface, the insert may define a projection at least partially defining the interior surface. In addition, a boot may be connected to the valve body and interlocked with the projection to prevent, or at least reduce, rotation of the insert relative to the valve body when the plug rotates within the internal cavity.

A controller valve with a valve body and a valve cartridge. The valve body has a water inlet, a primary water outlet, and a bypass water outlet. The valve cartridge is positioned within the valve body and has a diaphragm that fluidly isolates an upper chamber from a lower chamber within the valve cartridge. A piston is attached to the diaphragm and is configured to move within the valve cartridge between an upper position and a lower position. When the piston is in the upper position, the valve cartridge limits water flow through the primary water outlet and allows water flow through the bypass water outlet, and when the piston is in the lower position, the valve cartridge allows water flow through the primary water outlet and limits water flow through the bypass water outlet.