Disclosed is a method for repairing a piston-cylinder unit within a working machine or within an attachment, wherein a connection of the piston rod with the machine or implement structure is released and the piston rod, the piston and at least one bearing head is jointly removed from the cylinder housing as an assembly and replaced by a premounted substitute assembly consisting of piston rod, piston and at least one bearing head.

A device for actuating a valve by means of a rack meshing with an elliptical pinion connected with a sleeve so that one transmits a torque to the other. The connections between the pinion and the rack as well as the sleeve are separable, so that the angular reference positions of the pinion relative to both the rack and the sleeve can be adapted according to a predefined variation in the torque required for actuating the valve.

An electropneumatic positioner for a pneumatic actuator to operate a control device of a processing plant can include two modular pneumatic slots and a pneumatic control output. The two modular pneumatic slots can engage with a respective modular pneumatic component. The two pneumatic slots and the pneumatic components can be modularly matched to one another such that their respective pneumatic interfaces merge into one another when a pneumatic slot is engaged. The pneumatic control output can output a pneumatic control pressure signal to the pneumatic actuator. The two modular pneumatic slots and the pneumatic control output can form a pneumatic series connection.

A multi-stage shift pack assembly and method includes a frame assembly, a tool mounting movable relative to the frame assembly, and a removable cylinder shift pack secured to the frame assembly and having at least two cylinders that are independently actuatable for moving the tool mounting relative to the frame assembly a desired amount. The tool mounting is moved relative to the frame assembly by independently actuating cylinders of the removable cylinder shift pack.

A valve actuation system includes a drive device, equipped with an axial extension, which includes an actuating drive with a drive output side intended for coupling with a valve and an axial rear side opposite this, wherein the actuating drive has on its axial rear side a mounting interface for the attachment of an auxiliary device which interacts with the actuating drive wherein, in order to allow attachment of the particular auxiliary device which is to be mounted, or which is mounted, the mounting interface of the actuating drive is equipped with several different attachment devices which differ in their attachment possibilities and which can be used selectively. In this way, a high degree of variability in the attachment of auxiliary devices is provided.

A modular electrohydraulic actuator including an electric motor, a hydraulic pump driven by the electric motor, and a hydraulic actuator in fluid communication with the hydraulic pump. The hydraulic actuator includes a hydraulic cylinder supporting a pressure sleeve in which a piston and rod is adapted for reciprocating motion in response to a supply of pressurized fluid to a first side or a second side of the piston, wherein at least one of the electric motor, hydraulic pump, hydraulic cylinder, piston, piston rod or the pressure sleeve supported in the hydraulic cylinder is selectively removable and replaceable with a different component to vary at least one performance characteristic of the electrohydraulic actuator.

A hydraulic device of the present invention includes: a cylinder body (S) including a cylinder (1) and a rod (2) that moves retractably inside the cylinder (1); and a pump unit (30) that is formed with an oil passage (31) and discharges, at an intermediate position in the oil passage (31), liquid into the cylinder (1) through driving of a motor (M). The cylinder body (S) is connected to the pump unit (30) via an extension (40) having an oil passage (41) that provides communication between the oil passage (31) of the pump unit (30) and an interior of the cylinder (1).

Universal control circuitry for an electro-hydraulic valve actuator system includes logic gate circuitry to control one or more of a closing solenoid valve, an opening solenoid valve, an emergency shutdown solenoid valve, and a hydraulic fluid pump motor to route hydraulic fluid through a hydraulic circuit to actuate a valve via a hydraulic actuator according to received commands. The universal control circuitry is configured to control operation for multiple different configurations of a hydraulic valve actuator system including double-acting configurations, single-acting spring-to-open configurations, and single-acting spring-to-close configurations, each with or without an emergency shutdown arrangement (which may be configured to trip based on an external shutdown input alone or in combination with a local system power failure), a hydraulic accumulator, and maintained or momentary input commands.

An electropneumatic valve assembly comprises an electropneumatic pilot stage and a pneumatic power stage which is actuated by the pilot stage. Each pilot valve switches at least two power valves, and the valve assembly has a housing with an electrical signal input, with a compressed-air port, at least one vent port and at least one working outlet. The housing is layered with a pilot stage housing and a power stage housing connected along a substantially planar parting surface. At least one sealing element is between the pilot stage housing and power stage housing surrounding a control pressure region between the pilot stage housing and power stage housing. The control pressure region has two actuation regions for two power valves and has a duct-like connection with a defined flow cross section between the two actuation regions. An outlet of the associated pilot valve opens into the control pressure region.

A pipe joint has a tube for fluid detachably fitted thereto, and is connected to a hydraulic device such as a cylinder. The pipe joint is provided with a body into which the tube for fluid is inserted, and an attachment/detachment mechanism which is provided inside the body and which can attach/detach the tube for fluid. An inner sleeve for connecting the tube for fluid and the hydraulic device is provided in the body, the inner sleeve being interchangeable with orifices having different opening diameters.