Patent ID: 8002041

Claim:
Apparatus for use in subsea operations, which comprises: a housing comprising a generally tubular-shaped member having a first end and a second end; an accumulator located within the housing proximate the first end of the housing where the accumulator comprises a first chamber containing a pressurized gas at a pressure and a second chamber containing a pressurized fluid at a pressure, the first chamber and the second chamber are hermetically sealed from one another and track pressure of one another, the second chamber is in hydraulic connection with a hydraulic line of a subsea intervention system; a third chamber in the housing, the third chamber adjacent to the accumulator, where the third chamber contains a fluid and where pressure of the fluid in the third chamber tracks pressure in the accumulator; a movable piston located adjacent to the accumulator and within the housing proximate the second end of the housing, the movable piston having a first end and a second end, the first end having a cross-sectional area and the second end having a cross-sectional area, the piston being movable between a first position and a second position; the second end of the housing defines a cavity that includes a port that permits ambient subsea pressure to enter the cavity and impinge on the first end of the piston; the second end of the piston abuts and communicates with the third chamber thereby affecting the pressure in the third chamber.