Patent attributes
A device for shifting a sliding sleeve. The sliding sleeve is concentrically positioned within a well, and wherein the well is in communication with a hydrocarbon reservoir. In the most preferred embodiment, the device comprises an outer housing forming an annulus with the well and a power piston slidably disposed within the outer housing. The power piston includes an upper shoulder configured to form an annular chamber and a tubular chamber relative to the outer housing, a lower shoulder configured to form an atmospheric chamber relative to the outer housing. The device further comprises a first latch for preventing upward movement of the power piston, a second latch for preventing downward movement of the power piston, and wherein movement of the power piston shifts the sliding sleeve.
