Unico Corp.

Robb G Anderson

Thomas L Beck

Ronald G Peterson

Michael A MacDonald

Steven J Olson

James P McCrickard

Mark E Garlow

Harry W Schulz

Thmas L Beck

Michael A Macdonald

James P Mccrickard

An apparatus and method for pumping fluids, such as water and/or hydrocarbons, from a subterranean formation or reservoir, include a linear rod pump having a mechanical rack and pinion drive arrangement, adapted for attachment to a pumping mechanism, such as the polished rod at the top of a rod string in a hydrocarbon well. The rack gear, of the rack and pinion drive arrangement, is adapted for connection to, and movement with, the polished rod. The pinion gear does not translate with the rack gear, and is driven by a reversible motor for affecting up and down reciprocating motion of the rack gear and pumping mechanism. Some forms of the invention include a compressible gas counter-balance arrangement. Some forms of the invention include an electronic drive configured for dealing with electric power generated by the motor during a portion of the pumping cycle.

Linear rod pump apparatus and method

A method for operating a linear rod pump to pump fluids, such as water and/or hydrocarbons, from a subterranean formation or reservoir, include a linear rod pump having a mechanical rack and pinion drive arrangement, adapted for attachment to a pumping mechanism, such as the polished rod at the top of a rod string in a hydrocarbon well. The rack gear, of the rack and pinion drive arrangement, is adapted for connection to, and movement with, the polished rod. The pinion gear does not translate with the rack gear, and is driven by a reversible motor for affecting up and down reciprocating motion of the rack gear and pumping mechanism. Some forms of the invention include a compressible gas counter-balance arrangement. Some forms of the invention include an electronic drive configured for dealing with electric power generated by the motor during a portion of the pumping cycle.

Linear rod pump operating method

A method and apparatus for determining a fluid level and/or output flow during operation of a centrifugal pump, are provided, which may be used for production of gas and/or oil from a well, and include a vector feedback model to derive values of torque and speed from signals indicative of instantaneous current and voltage drawn by the pump motor, a pump model which derives values of the fluid flow rate and the head pressure for the pump from torque and speed inputs, a pumping system model that derives, from the estimated values of the pump operating parameters, an estimated value of fluid level and other pumping system parameters. Controllers responsive to the estimated values of the pumping system parameters control the pump to maintain fluid level at the pump input, near an optimum level, or within a safe operating range and/or output flow from the pump.

Determination and control of wellbore fluid level, output flow, and desired pump operating speed, using a control system for a centrifugal pump disposed within the wellbore

An improved method and apparatus are provided for constructing and operating a linear actuator, and equipment incorporating a linear actuator, by operatively connecting a pressure biasing pneumatic arrangement between the driving member and the driven member of a mechanical linear actuator for applying a unidirectional biasing force between the driving and driven members, along an axis of motion, regardless of the location or movement of the driving and driven elements with respect to one another along the axis of motion. The pneumatic biasing arrangement is also configured, connected and operated to reduce the force which must be exerted by the driving and driven members in extending and retracting the linear actuator. The pneumatic biasing arrangement may further be configured for preferentially aiding extension or retraction of the actuator.

Pneumatic biasing of a linear actuator and implementations thereof

A control system for the operation of a centrifugal pump which may be used for production of gas and/or oil from a well. The control system includes vector feedback model to derive values of torque and speed from signals indicative of instantaneous current and voltage drawn by the pump motor, a pump model which derives values of the fluid flow rate and the head pressure for the pump from torque and speed inputs, a pumping system model that derives from the estimated values of the pump operating parameters an estimated value of a pumping system parameter and controllers responsive to the estimated values of the pumping system parameters to control the pump to maintain fluid level at the pump input near an optimum level.

Control system for centrifugal pumps

A system for controlling operation of a progressing cavity pump to maintain the motor operating under power disturbance conditions. For a blackout condition, a backspin controller uses regenerative power to provide controlled deceleration of the pump, counteracting backspin and preventing backspinning freely. For a brownout condition, a power dip controller weakens the motor field to maximize pump production consistent with reduced input power availability. For a phase loss or voltage imbalance condition, a phase loss controller reduces motor power output to keep drive system output power at or below single phase capacity.

Growing community of inventors

Eden Prairie, MN, United States of America

Robb G Anderson