A number of variations may include a fluid accumulator comprising, a housing and at least one movable piston wherein the piston separates an interior of the housing into a first chamber constructed and arranged for containing a first fluid, and a second chamber constructed and arranged for containing a second fluid, and wherein the first chamber has an first fluid opening and a first fluid exhaust constructed and arranged to expel excess first fluid from the fluid accumulator and prevent first fluid from entering the second chamber.

A piston accumulator has an accumulator housing and a separating piston (8) guided for longitudinal motion in the accumulator housing. The separating piston separates a liquid side (4) from a gas side (10) in the accumulator housing. Liquid unintentionally transitions from the liquid side (4) to the gas side (10) despite a piston seal on the separating piston (8). By a return device (28), the transitioned liquid is at least partially returned from the gas side (10) of the accumulator housing to the liquid side (4) of the accumulator housing.

The present disclosure relates to a miniature pressure compensating device (10), for balancing pressure fluctuations in a hydraulic system, comprising at least one shell (12), at least one hollow hydraulic cylinder (16), at least one reciprocating piston (26) and at least one non-return valve (NRV) (28). The hydraulic cylinder (16) comprises at least one dual charging valve port (22) for facilitating charging of both said compressible and incompressible fluid and at least one built-in two-tier scaling mechanism (24) comprising at least one metal-to-metal seal (24a) and at least one secondary seal (24b) to achieve effective isolation of the incompressible and compressible fluids. The present miniature pressure compensating device (10) has a volume below 13 cc.

A wellhead pressure reduction and power generating assembly includes a wellhead, a supply pipe, a prime mover, a pump, and an accumulator bank. The wellhead is configured to supply a pressurized production fluid flow and is in fluid communication with the supply pipe. The prime mover is configured to induce a pressure drop within the pressurized production fluid flow and is in fluid communication with the supply pipe. The pump is configured to receive a mechanical force of the prime mover and operatively coupled with the prime mover. The accumulator bank is configured to accumulate a pressurized hydraulic fluid and is in fluid communication with the pump.

A piston accumulator has an accumulator housing and a separating piston (8) guided for longitudinal motion in the accumulator housing. The separating piston separates a liquid side (4) from a gas side (10) in the accumulator housing. Liquid unintentionally transitions from the liquid side (4) to the gas side (10) despite a piston seal on the separating piston (8). By a return device (28), the transitioned liquid is at least partially returned from the gas side (10) of the accumulator housing to the liquid side (4) of the accumulator housing.

This invention relates to hydraulic energy storage and management systems. In particular, this invention relates to a hydraulic energy management system that has a reconfigurable energy storage and release capability that adjusts to varying available energy input and power demand output requirements. The hydraulic energy management system can be resized by a hydraulic bridge circuit to permit hydraulic power units to be added or removed, both physically and operationally, to capture available energy over time, adjust to peak demand cycles, and maintain power output in the event of a failure of a portion of the system.

Device for recovering hydraulic energy in a machine comprising at least a first differential cylinder-piston assembly having a differential cylinder with a separate rod and base side, at least a second differential cylinder-piston assembly having a differential cylinder with a separate rod and base side, and at least one hydraulic accumulator that can be hydraulically connected to at least one of the differential cylinder-piston assemblies, wherein the differential cylinder-piston assemblies are mechanically coupled to one another, and wherein the potential energy of at least one of the differential cylinder-piston assemblies retracting under a compressive load can at least partially be stored in the hydraulic accumulator.

A hydraulic control system HCS for controlling a variable ratio transmission of a power generating system. A hydraulic motor/pump unit 140 is operably connected to a superposition gear, and is connected to a hydraulic circuit that comprises an orifice 28 and/or a relief valve 29 that opens at a predetermined hydraulic pressure. The hydraulic circuit switches between a variable low-speed operating mode and a torque limiting high-speed operating mode. In the torque limiting high-speed operating mode the hydraulic motor/pump unit 140 is driven by the superposition gear and drives hydraulic fluid through the orifice 28 and/or relief valve 29 to provide a passive torque limiting function. In the variable low-speed operating mode the hydraulic motor/pump unit 140 drives the superposition gear and the hydraulic control system provides a desired rotor 101 speed by controlling hydraulic fluid flow rate through the hydraulic motor/pump unit 140.

A system for storing and releasing hydraulic energy having a controller, a pressure source, a bidirectional valve fluidly connected to the pressure source, an expandable vessel fluidly connected to the bidirectional valve having a plurality of axial folds between first and second ends, and a bidirectional port connected to the pressure source. As the plurality of axial folds expand, a contracted volume of pressure expands increasing stored hydraulic fluid energy in the expandable vessel. As the plurality of axial folds contract, the expanded volume reduces, releasing stored hydraulic fluid energy to nearby subsea equipment on demand as changes in hydraulic fluid energy requirements for the subsea equipment changes. Simultaneously, hydrostatic seawater pressure of seawater on the expandable vessel is counteracted with the hydrostatic pressure of fluid inside the expandable vessel.

Some of the present systems include a hydraulic power storage system having an accumulator configured to supply pressurized hydraulic fluid to a hydraulically actuated device to actuate the hydraulically actuated device and a drain in fluid communication with the accumulator and including a valve that is actuatable to drain hydraulic fluid from the hydraulic power storage system such that an internal pressure of the accumulator is reduced and a flow restrictor configured to reduce a flow rate of hydraulic fluid through the valve, a hydraulic pump configured to pressurize the accumulator, a pressure sensor configured to capture data indicative of the internal pressure of the accumulator, and a processor configured to actuate the hydraulic pump to increase the internal pressure of the accumulator if the internal pressure of the accumulator, as indicated in data captured by the pressure sensor, falls below a threshold pressure.