A valve body comprises an inner compartment extending along a longitudinal axis from a second end portion towards a first end portion. First, second, and third fluid ports in to the valve body are perpendicular to the longitudinal axis. The second fluid port is between the third and the first fluid port. A fourth fluid port is parallel to the longitudinal axis. A spool is configured to selectively reciprocate in the inner compartment. The spool comprises a first fluid receptacle configured to block fluid flow to the third fluid port and to fluidly communicate with the second fluid port when the spool adjoins the first end portion. The first fluid receptacle is configured to fluidly communicate with the second fluid port and with the third fluid port when the spool adjoins the second end portion. A second fluid receptacle is configured to receive fluid pressure from the fourth fluid port.

A valve, in particular a 4/2-way slide valve (60), includes a valve piston (67), which is guided in a longitudinally movable manner in a valve housing (25), for selectively connecting and disconnecting fluid connections in the valve housing (25), such as a pressure supply connection (P), a tank connection (T), and two utility connections (A, B). A magnetic system (49), to which current can be supplied, controls the valve piston (67). When no current is supplied to the magnetic system (49), the control pressure at one of the utility connections (A, B) can be set, in particular limited, by a control device (62, 70, 79, 80, 88) arranged in the valve housing.

A control system can include a resettable chamber and a bidirectional valve. The bidirectional valve can be switchable between (i) a first configuration for enabling fluid flow from the control line into a first port of a well tool and from a second port of the well tool into the resettable chamber, and (ii) a second configuration for enabling fluid flow from the control line into the second port of the well tool and from the first port of the well tool into the resettable chamber. The bidirectional valve can be switched from the first configuration to the second configuration in response to pressure being applied to the control line.

Systems and methods are provided for enhanced valves. One embodiment is a hydraulic valve that includes a housing that defines a first port, a second port, and a third port for a hydraulic fluid, and a sleeve disposed within the housing that defines openings in fluid communication with the second port and the third port. The valve also includes a slide comprising a head and a shaft. The shaft is disposed within the sleeve and the slide is movable in a lengthwise direction from a closed position to an open position. The head includes a circumferential lip that extends perpendicular to the lengthwise direction, and that abuts the sleeve when the slide is in the closed position to prevent flow of the hydraulic fluid from the first port. The shaft provides a flow path between the second port and the third port when the slide is closed.

An actuating unit for a process valve is described, which comprises a pilot valve unit, a separate removable seal arranged between two parts through which a fluid can flow, and a piston configured for the adjustment of the process valve. The seal has through openings for the passage of fluid, and the adjacent parts have holes, such that different holes are in fluid communication with each other via the through openings or are fluidically separated due to an intermediate wall portion of the seal depending on the fitting position of the seal. A process valve having such an actuating unit is furthermore described.

A multi-way poppet valve and methods for using the same are provided. In one embodiment, the poppet valve includes a manifold and a poppet assembly including an inner poppet and an outer poppet defining one or more lands. The poppet assembly can dimensioned for receipt within a bore of the manifold and configured to move longitudinally within the manifold. The inner poppet and the outer poppet can also be formed in two separate pieces that are capable of moving with respect to one another. This design can allow the lands of the poppet assembly to form fluid-tight seals (e.g., metal-metal, metal-gasket, etc.) with the manifold. In this manner, the poppet valve can move longitudinally between open and closed positions where the fluid-tight seals respectively allow or inhibit fluid flow between selected ports of the valve.

An example valve includes: a housing having a first longitudinal cavity therein; a sleeve disposed, at least partially, in the first longitudinal cavity, where the sleeve has a second longitudinal cavity therein, and includes a first seat formed as a protrusion from an interior peripheral surface of the sleeve; a poppet mounted within the second longitudinal cavity and configured to move axially therein; and a bushing mounted, at least partially, in the second longitudinal cavity, such that the bushing is floating and is allowed to move axially in the second longitudinal cavity, where the bushing is hollow and defines a first port at a distal end of the bushing and defines a second seat at a proximal end of the bushing, and where the sleeve defines a second port and a third port disposed on an exterior peripheral surface of the sleeve.

A control unit for pneumatic actuation of a cylinder, in particular an active creel of a textile-processing machine or a cabling machine, having a compressed air inlet for connecting a compressed air supply, a working air outlet for operating the cylinder, which acts at least on one side, a valve unit arranged between the compressed air inlet and the working air outlet, and an operating element for opening the valve unit to trigger a lifting movement of the cylinder. In order to provide a control unit for pneumatic actuation of an active creel, the actuation of the creel being particularly simple by the control unit, so that an operator can use the creel more easily, quickly and safely, and in addition the creel is protected from damage by incorrect operation, the control unit for achieving a self-retaining valve function, in which the lifting movement of the cylinder is fully executed with a single and/or brief actuation of the operating element, and for the control unit is connected to an end position sensor of the cylinder such that, when the end position sensor is activated, the valve unit is closed and/or the cylinder connected to the working air outlet is automatically depressurised when or after an end position is reached.

For the purpose of providing a valve arrangement for controlling pneumatic drives with protection against a sudden automatic change in the initial switching position without an input signal in the event of a fault in a resetting device of a pilot stage and, for this situation, effective fault identification by purely pneumatic means, said valve arrangement comprises a first and a second working connection (1; 2), which can be connected to a drive, and a first and a second electropneumatically pilot-controlled directional valve, in which valve arrangement one or both directional valves is or are arranged upstream of the working connections (1; 2) for the purpose of influencing and venting said working connections, wherein the pilot stages of both directional valves are of automatically resetting design and the second directional valve is designed for alternately assuming an inoperative position and a switching position and the pilot stage of the first directional valve has an external control connection (8; 8) which can be influenced by means of the second directional valve in its switching position and can be vented by means of said second directional valve in its inoperative position, wherein the second directional valve has, as a resetting device for the main stage (14), an air spring (19) which can be influenced and can be vented externally by means of the first directional valve, and a change in state between influencing or venting of the air spring (19) after the first directional valve assumes a switching position takes place only depending on the change in the switching state of the first directional valve, and a change in state between influencing or venting at one working connection (1; 2) after previous influencing or venting which took place with the second directional valve assuming the switching position takes place only depending on the second directional valve assuming the inoperative position.

A hydraulic system is provided. The hydraulic system includes a pump, a load sense conduit, a tank conduit, a function workport, and a function control valve. The hydraulic system further includes a function poppet valve arranged between the function workport and the function control valve and having a function poppet vent passage, and a system control valve arranged downstream of the function control valve. The system control valve is biased into a first position where fluid communication between the function poppet vent passage and the tank conduit is prevented and fluid communication between the load sense conduit and the tank conduit is provided. The system control valve is selectively movable to a second position where fluid communication between the function poppet vent passage and the tank conduit is allowed and fluid communication between the load sense conduit and the tank conduit is prevented.