A sensor system for a dual bottle accumulator utilized with a subsea blowout preventer that monitors piston position with a position sensor in the hydraulic bottle, the gas pressure in the associated gas bottle with one or more pressure sensors, and sensors and remote actuators for associated valves.

A counter pressure valve arrangement for controlling a pressure level of a hydraulic fluid in a return line from a hydraulic actuator arrangement. The counter pressure valve arrangement comprises a counter pressure valve having: a moveable valve member; a counter pressure regulating port configured for being connected to the hydraulic actuator arrangement via the return line; a tank port configured for being connected to a tank or low pressure reservoir for storing low pressure hydraulic fluid; and a pump port configured for being connected to a source of pressurised hydraulic fluid. A first position of the valve member effects fluid communication between the pump port and the counter pressure regulating port for supplying pressurised hydraulic fluid to the return line, and a second position of the valve member effects fluid communication between the counter pressure regulating port and the tank port for discharging hydraulic fluid from the return line to the tank.

Novel Counterbalance valves, more particularly, to counterbalance valves that provide hold, capture, and motion control benefits of prior art CB valves while improving upon one or more performance characteristics of current CB valves are herein disclosed. The novel counterbalance valves are useful, inter alia, for providing good system stability across a range of load pressures and/or reducing power consumption (improving energy efficiencies) as compared with prior art devices.

A counter balance valve (71L) is located between a directional control valve (23) and a hydraulic motor (32L) and provided on the way of a pair of supply/discharge lines (25A, 25B). The counter balance valve (71L) allows a spool (72L) to be displaced axially based on a pressure difference between the supply/discharge lines (25A, 25B). The counter balance valve (71L) includes a communicating passage (73L) for communicating the supply/discharge lines (25A, 25B) when the displacement of the spool (72L) exceeds a predetermined amount (X.sub.CM), based on a pressure difference between the supply/discharge lines (25A, 25B). The communicating passage (73L) is provided in the spool (72L) of the counter balance valve (71L).

A system for damping mass-induced vibrations in a machine having a long boom or elongate member, the movement of which causes mass-induced vibration in such boom or elongate member. The system comprises multiple pressure sensors operable to measure pressure fluctuations in the hydraulic fluid pressures in the non-load holding and load holding chambers of a hydraulic actuator connected to the boom or elongate member that result from mass-induced vibration, and a processing unit operable to control a first control valve spool in a pressure control mode and a second control valve spool in a flow control mode in order to adjust hydraulic fluid flow to the actuator's load holding chamber to dampen the mass-induced vibration. The system further comprises a control manifold fluidically interposed between the actuator and control valve spools that causes the first and second control valve spools to operate, respectively, in pressure and flow control modes.

An example counterbalance valve includes: a poppet configured to be subjected to a fluid force by fluid received at a first port, and a fluid force by a pilot pressure fluid signal received at a pilot port; a first setting spring disposed in a first chamber and applying a first biasing force on the poppet; and a second setting spring disposed in a second chamber and applying a second biasing force on the poppet, wherein the first chamber and the second chamber are vented to an external environment of the counterbalance valve, wherein the second setting spring is in parallel with the first setting spring such that an equivalent biasing force acting on the poppet in the distal direction comprises a sum of the first biasing force and the second biasing force.

A balancing valve includes four ports. While the pressures at a pair of balancing ports of a hydraulic balancing valve are equal, the valve maintains two other ports in a closed position. Upon a pressure differential between the balancing ports, fluid communication can occur between one of the balancing ports and either of the other ports based upon the direction of the pressure differential. A hydraulic ride control system utilizes the balancing valve together with other control valves to provide ride control functionality.

A balancing valve includes four ports. While the pressures at a pair of balancing ports of a hydraulic balancing valve are equal, the valve maintains two other ports in a closed position. Upon a pressure differential between the balancing ports, fluid communication can occur between one of the balancing ports and either of the other ports based upon the direction of the pressure differential. A hydraulic ride control system utilizes the balancing valve together with other control valves to provide ride control functionality.

A counter balance valve (71L) is located between a directional control valve (23) and a hydraulic motor (32L) and provided on the way of a pair of supply/discharge lines (25A, 25B). The counter balance valve (71L) allows a spool (72L) to be displaced axially based on a pressure difference between the supply/discharge lines (25A, 25B). The counter balance valve (71L) includes a communicating passage (73L) for communicating the supply/discharge lines (25A, 25B) when the displacement of the spool (72L) exceeds a predetermined amount (X.sub.CM), based on a pressure difference between the supply/discharge lines (25A, 25B). The communicating passage (73L) is provided in the spool (72L) of the counter balance valve (71L).

An example counterbalance valve includes: a poppet configured to be subjected to a fluid force by fluid received at a first port, and a fluid force by a pilot pressure fluid signal received at a pilot port; a first setting spring disposed in a first chamber and applying a first biasing force on the poppet; and a second setting spring disposed in a second chamber and applying a second biasing force on the poppet, wherein the first chamber and the second chamber are vented to an external environment of the counterbalance valve, wherein the second setting spring is in parallel with the first setting spring such that an equivalent biasing force acting on the poppet in the distal direction comprises a sum of the first biasing force and the second biasing force.