Abstract: A submersible, hydraulically actuated, multi-stage double-acting positive displacement pump system is provided. The system has a hydraulically actuated reciprocating linear double-acting motor centrally disposed between and connected to double-action fluid pumps on either side of the motor, with pistons of each of pump and the motor all in the annular space between an inner wall of the apparatus' cylindrical body and the outer wall of a cylindrical production fluid conduit concentrically disposed within the body, to pump wellbore fluid from outside the assembly through the pumps and into the central production fluid conduit. The rate and direction of hydraulic fluid flow through the actuator may be controlled by VFD motors and PLC controller on the ground, and through at least one electromechanical valve and two limit switches mounted to the downhole components.

Abstract: A submersible, hydraulically actuated, multi-stage double-acting positive displacement pump system is provided. The system has a hydraulically actuated reciprocating linear double-acting motor centrally disposed between and connected to double-action fluid pumps on either side of the motor, with pistons of each of pump and the motor all in the annular space between an inner wall of the apparatus' cylindrical body and the outer wall of a cylindrical production fluid conduit concentrically disposed within the body, to pump wellbore fluid from outside the assembly through the pumps and into the central production fluid conduit. The rate and direction of hydraulic fluid flow through the actuator may be controlled by VFD motors and PLC controller on the ground, and through at least one electromechanical valve and two limit switches mounted to the downhole components.