Tubing pressure insensitive pressure compensated actuator for a downhole tool and method

摘要

A tubing pressure insensitive, pressure compensated actuator system includes a housing having a bore therein. A force transmitter sealingly moveable within the bore. The force transmitter defining with the bore two fluid chambers. The two fluid chambers being in fluid communication with each other, one at each longitudinal end of the force transmitter. An activator in one or both of the two fluid chambers and operatively connected to the force transmitter. At least two seals sealingly positioned between the housing and the force transmitter. One of the seals disposed near one end of the force transmitter and another of the seals disposed near another end of the force transmitter. A separate compensation piston disposed in the housing so as to expose one end of the compensation piston to tubing pressure and to expose the other end of the compensation piston to a fluid volume including the fluid chambers. Also included is a method for reducing force requirements of an actuator.