A fluid pumping device includes a barrel body and a piston mechanism. The barrel body has a cavity. The piston mechanism includes a piston member, a first annular plug, and a second annular plug. The piston member movably extends into the cavity. The piston member has two annular grooves where the first and the second annular plugs are disposed respectively. Each of the first the second annular plugs has an annular base section and an annular protrusion section. The annular protrusion section has a first outer annular abutting face. The annular base section has an outer annular base face. The first outer annular abutting face abuts against the inner wall of the cavity.

A fluid pumping device includes a barrel body and a piston mechanism. The barrel body has a cavity. The piston mechanism includes a piston member, a first annular plug, and a second annular plug. The piston member movably extends into the cavity. The piston member has two annular grooves where the first and the second annular plugs are disposed respectively. Each of the first the second annular plugs has an annular base section and an annular protrusion section. The annular protrusion section has a first outer annular abutting face. The annular base section has an outer annular base face. The first outer annular abutting face abuts against the inner wall of the cavity.

A pressing tool for plastically deforming a tubular workpiece. The pressing tool comprises a drive, a reservoir for providing a hydraulic fluid, a coupling interface for coupling the pressing tool to a pressing jaw assembly, and a hydraulic pump valve apparatus. The hydraulic pump valve apparatus comprises a pressure cylinder, an operating cylinder, and a pressure-relief valve element which is adapted to open a fluidic passage from the operating cylinder to the reservoir when a predefined maximum pressing pressure is reached and keep it open until the operating piston has returned to a first position.

A pressing tool for plastically deforming a tubular workpiece. The pressing tool comprises a drive, a reservoir for providing a hydraulic fluid, a coupling interface for coupling the pressing tool to a pressing jaw assembly, and a hydraulic pump valve apparatus. The hydraulic pump valve apparatus comprises a pressure cylinder, an operating cylinder, and a pressure-relief valve element which is adapted to open a fluidic passage from the operating cylinder to the reservoir when a predefined maximum pressing pressure is reached and keep it open until the operating piston has returned to a first position.

In some aspects, waterjet cutting pressurization systems can include a water pump: (i) having a pressurization chamber and (ii) having a high-pressure water seal maintaining water pressure within the chamber; and a leak detector in fluid communication with the high-pressure water seal and configured to monitor a leak rate of a fluid from the high-pressure water seal.

In some aspects, waterjet cutting pressurization systems can include a water pump: (i) having a pressurization chamber and (ii) having a high-pressure water seal maintaining water pressure within the chamber; and a leak detector in fluid communication with the high-pressure water seal and configured to monitor a leak rate of a fluid from the high-pressure water seal.

A fluid delivery device comprises a hydraulic pump chamber having a hydraulic fluid. A fluid reservoir is coupled to the hydraulic pump chamber and is configured to contain a fluid deliverable to a patient. A first actuator is coupled to the hydraulic pump chamber and is configured to pressurize the hydraulic pump chamber and configured to transfer energy through the hydraulic pump chamber to the fluid reservoir. A second actuator is coupled to the hydraulic pump chamber and is configured to pressurize the hydraulic pump chamber and configured to transfer energy through the hydraulic pump chamber to the fluid reservoir.

A fluid delivery device comprises a hydraulic pump chamber having a hydraulic fluid. A fluid reservoir is coupled to the hydraulic pump chamber and is configured to contain a fluid deliverable to a patient. A first actuator is coupled to the hydraulic pump chamber and is configured to pressurize the hydraulic pump chamber and configured to transfer energy through the hydraulic pump chamber to the fluid reservoir. A second actuator is coupled to the hydraulic pump chamber and is configured to pressurize the hydraulic pump chamber and configured to transfer energy through the hydraulic pump chamber to the fluid reservoir.

At least one pressure exchange unit with a hollow cylindrical body, a piston sliding in the body, the piston including a piston head separating the interior of the cylindrical body into a downstream chamber and an upstream chamber, the downstream chamber being provided with a device for the admission and discharge of water to be treated, the upstream chamber being provided with a five-way distributor linkage including, for hydraulic balancing, two pressurized liquid supply orifices, two orifices for the evacuation of the liquid and an opening in communication with the upstream chamber.

At least one pressure exchange unit with a hollow cylindrical body, a piston sliding in the body, the piston including a piston head separating the interior of the cylindrical body into a downstream chamber and an upstream chamber, the downstream chamber being provided with a device for the admission and discharge of water to be treated, the upstream chamber being provided with a five-way distributor linkage including, for hydraulic balancing, two pressurized liquid supply orifices, two orifices for the evacuation of the liquid and an opening in communication with the upstream chamber.