A valve with an inlet, an outlet that is connected to the inlet via a fluid connection, and a valve body which can be brought by displacing it along a displacement direction into a first position, in which the fluid connection is blocked, and a second position, in which the fluid connection is open, wherein the inlet is designed and arranged in such a way that a fluid entering through the inlet exerts a total force on the valve body that at least also acts in a force direction which is perpendicular to the displacement direction when the valve body is in the first position.

A non-curable injectable ester containing packing material for use in the repair of leaking valves contains a calcium sulfonate grease containing at least one polyalphaolefin, an ester, an anti-wear/anti-galling agent, a binding/thickening agent and a plasticizing agent.

A downhole tool control system for a drill string rotary steerable tool that includes a body having an inner chamber, a piston gallery extending between the inner chamber and a piston port, and an exhaust gallery extending between the inner chamber and an exhaust port. A spool in the inner chamber is movable into a plurality of positions to direct and control the timing and duration of the flow of drilling fluid to energize pistons of the rotary steerable tool, and to de-energize the pistons. The spool includes a first passage in fluid communication with a drilling fluid inlet port but not the exhaust port, and a second passage in fluid communication with the exhaust port but not the drilling fluid inlet port.

A servovalve system comprising a pilot stage valve in communication with an hydraulic stage valve, the hydraulic stage valve comprising a valve member movably mounted in a valve chamber to selectively meter fluid flow in a flow path from an upstream inlet port to a downstream outlet port and at least two variable-sized orifices disposed in the flow path between the inlet and outlet ports, an upstream pressure sensor, a downstream pressure sensor, a fluid temperature sensor, a position sensor sensing a linear position of the valve member, a controller that receives input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor; and the controller configured to provide a control signal to the pilot stage valve as a function of the input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor.

A servovalve system comprising a pilot stage valve in communication with an hydraulic stage valve, the hydraulic stage valve comprising a valve member movably mounted in a valve chamber to selectively meter fluid flow in a flow path from an upstream inlet port to a downstream outlet port and at least two variable-sized orifices disposed in the flow path between the inlet and outlet ports, an upstream pressure sensor, a downstream pressure sensor, a fluid temperature sensor, a position sensor sensing a linear position of the valve member, a controller that receives input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor; and the controller configured to provide a control signal to the pilot stage valve as a function of the input from the upstream pressure sensor, the downstream pressure sensor, the fluid temperature sensor and the position sensor.

An example valve includes: a valve body defining a bore, an inlet port, an outlet port, and a signal cavity; a spool movable in the bore to shift between a first position and an intermediate position, where the spool has a first end and a second end, where the outlet port is fluidly connected to the second end, where the valve body defines a spring cavity adjacent the first end of the spool to house a spring, where the first end is subjected to a load-sense pressure signal, and where when the spool is in the first position, the spool disconnects the inlet port from the outlet port and connects the inlet port to the signal cavity; and a valve actuator that, when activated, connects the signal cavity to the second end of the spool to move the spool in the bore from the first position to the intermediate position.

An example valve includes: a valve body defining a bore, an inlet port, an outlet port, and a signal cavity; a spool movable in the bore to shift between a first position and an intermediate position, where the spool has a first end and a second end, where the outlet port is fluidly connected to the second end, where the valve body defines a spring cavity adjacent the first end of the spool to house a spring, where the first end is subjected to a load-sense pressure signal, and where when the spool is in the first position, the spool disconnects the inlet port from the outlet port and connects the inlet port to the signal cavity; and a valve actuator that, when activated, connects the signal cavity to the second end of the spool to move the spool in the bore from the first position to the intermediate position.

Methods of using split G-quadruplexes associated with functional tags for associating said tags to target nucleic acids. Methods include use of split G-quadruplexes associated with detection tags for the detection of target nucleic acids, and use of split G-quadruplexes associated with capture tags for detection or capture of target nucleic acids.

A hydraulic system includes a circulation pump assembly (2) provided with a speed controller (4, 26), a hydraulic circuit (A, B) connected to the circulation pump assembly (2) as well as a mechanical switch device (86, 88; 120, 122; 120″, 122″) which is subjected to pressure from a fluid in the hydraulic circuit (A, B) and which can be moved into at least two different switch positions. The mechanical switch device (28; 86, 28; 120, 122) can be moved by the circulation pump assembly (2) by way of a hydraulic coupling via the fluid. The speed controller is configured to initiate a movement of the switch device (86, 88; 120, 122; 120″, 122″) by way of at least one hydraulic force acting thereon and causing a movement of the switch device (86, 88; 120,122; 120″, 122″), produced via the hydraulic circuit, via a speed adaptation of the circulation pump assembly.

The invention relates to a valve device having a valve housing, and comprising a main piston (4) that is arranged in an axially slidable manner in a piston bore of the valve housing (2), via which a first consumer connection (A) and a second consumer connection (B) can be alternately connected to a pressure connection (P) and a tank connection (T1, T2) by way of the action of a first magnetic actuating system (6) and a second magnetic actuating system (8) and comprising two pilot pistons (14, 16). The invention is characterized in that in an actuated state of the respective pilot piston (14, 16), the main piston (4) follows the movement of said pilot piston (14, 16) due to the force ratio adjusting itself thereon, thus actuating the fluid-carrying connection between the pilot chamber (10, 12) of said pilot piston (14,16) and the assignable tank connection (T1, T2) such that pilot oil flows.