Patent ID: 6497281
Filing Date: 2002-12-24
Classification: E21B,F04B

Abstract:
In a well that extends downhole through a production formation that flows fluid thereinto; a wellhead at the top thereof opposed to the bottom thereof; a production tubing extending from the wellhead downhole within proximity of the formation; an elongate member; a support adjacent the wellhead by which the elongate member is supported for movement along the longitudinal axis of the tubing; a storing device operable in both directions to retrieve and extend said elongate member therefrom;a well pumping apparatus telescopingly received within the tubing and having a long pump barrel within which a plunger reciprocates for lifting fluid from the bottom of the well up through the tubing and to the wellhead as the plunger upstrokes, and for filling the barrel below the plunger as the plunger upstrokes; means connecting the elongate member to said storage device and to said plunger for reciprocating the plunger; a control system for responsively lowering and raising the elongate member to thereby slowly remove fluid from the pump barrel during the plunger upstroke and to force formation fluid into the tubing and thereby produce fluid from the well, wherein said well pumping apparatus receives mixed compressible and non-compressible fluids within the barrel; the compressible and non-compressible fluid is lifted up into the tubing string to aerate the fluid column in the tubing string, thereby reducing the density of the fluid in the tubing string which improves production of the well; said control system comprises a position sensor responsive to plunger position to move said elongate member axially into and out of the well within a selected range of operation; timing means by which the rate of flow from the formation equals the rate of production of the pump apparatus during one cycle of operation; whereby: the plunger is cycled an upstroke followed by a downstroke during a cycle of operation which occurs during an interval of time equal to the rate of fluid flow from the formation to fill the pump barrel with well fluid.