US-20260125969-A1 - ROD PUMP WITH NON-LOCKING ACTUATOR

US20260125969A1US 20260125969 A1US20260125969 A1US 20260125969A1US-20260125969-A1

Abstract

A rod pump system is configured to provide efficient pumping operations in a downhole environment containing high gas content, using a non-locking actuator. The non-locking actuator assembly is configured to respond to high-gas conditions and automatically overcome a gas locked pump state thereby returning the system to normal pumping conditions. This system is appended to the traveling valve closed cage within a conventional rod pump in place of a conventional seat plug.

Inventors

Geoff Steele

Assignees

VANTAGE PRODUCTION TOOLS INC.

Dates

Publication Date: 20260507
Application Date: 20251219

Claims (10)

1 . A traveling valve actuator, for use with a traveling valve which reciprocates within a pump barrel and having a traveling valve element, comprising: (a) a distal valve responsive to fluid conditions in a pump barrel to close the distal valve when the pump barrel fluid is gas dominated and open the distal valve when the pump barrel fluid comprises liquid; (b) pressure cylinder including an activation chamber defined in part by the distal valve and a piston which reciprocates within the pressure cylinder, the piston having a one-way check valve configured to allow fluid to enter the activation chamber from the pump barrel; (c) an intake housing having at least one port open to the pump barrel and the one-way check valve; and (d) a prong connected to the piston which reciprocates upwards to impinge on the traveling valve ball when the activation chamber is closed by the distal valve and the one-way check valve.
2 . The actuator of claim 1 , wherein the distal valve comprises a valve element which has a specific gravity greater than a gas and less than a liquid.
3 . The actuator of claim 2 wherein the valve element comprises a hollow element.
4 . The actuator of claim 3 wherein the hollow element is a hollow sphere, optionally pressurized above atmospheric pressure.
5 . The actuator of claim 4 wherein the hollow sphere is made from titanium.
6 . The actuator of claim 1 wherein the intake housing defines an intake manifold which defines a fluid flowpath from the at least one port into a check valve chamber formed within a distal end of a rod crossover connected between the piston and the prong; wherein the check valve permits fluid flow from the check valve chamber to the activation chamber when the check valve is open, but which does not permit fluid flow from the activation chamber to the check valve chamber.
7 . The actuator of claim 1 wherein the intake housing comprises a filter cage and a filter element, for filtering fluids entering the non-locking actuator.
8 . The system of claim 6 wherein the filter element comprises a porous sintered metal cup, disc or tube.
9 . A method of opening a traveling valve element during a pump upstroke, in a rod pump, the method comprising the steps of: (a) providing an actuator having an activation chamber and a piston connected to a prong, moveable between a retracted position and an extended position where the prong extends upwards to contact the traveling valve element; (b) when the pump barrel is at least partially filled with a liquid, allowing liquid to enter and exit the activation chamber during normal operation where the piston and prong are retracted; (c) storing gas within the activation chamber when the pump barrel is filled with gas, such that the piston and the prong are extended when the activation chamber pressure exceeds pressure within the pump barrel.
10 . The method of claim 9 wherein the activation chamber seals to store gas by the action of (a) a distal valve comprising a specific gravity element which has a specific gravity greater than gas and less than oil or water, or mixtures thereof; and (b) a check valve permitting fluid flow into the activation chamber but which does not permit fluid flow out of the activation chamber.

Description

CROSS REFERENCE This application is a continuation of U.S. application Ser. No. 18/594,750, filed on Mar. 4, 2024, which claims the priority benefit of U.S. Provisional Patent Application No. 63/488,148 filed on Mar. 2, 2023. The entire contents of these documents are incorporated herein by reference. FIELD OF THE INVENTION The present invention generally relates to a rod pump system for use in a subterranean wellbore which may experience conditions conducive to gas locking. BACKGROUND While there has been expansive growth in the capital spending for drilling and completion operations of complex wellbores, there has been virtually no change in capital spend and operating budgets for the production and artificial lift operations of the same wellbores. Complex wellbores present complex behaviors in the flow and mixing of the four phases found downhole: oil, water, gas, and solids. In the build section, known drilling techniques present a build rate limitation of approximately 30° per 100 m of measured depth as the orientation transitions toward the substantially horizontal wellbore segment. The vertical height of this build section in the wellbore may be at least a hundred meters in length and presents a tortuous path in which landing and operating pumping systems is challenging and often uneconomical. Therefore, most conventional pumping operators land pumping systems at or above the build section of the wellbore and thereby avoid the more tortuous section of the well's geometry. Consequently, many pumping systems are landed at least a hundred meters vertically above the producing formation and cannot rely on traditional pumping workflows deployed successfully in substantially vertical wellbores. In these workflows, the pump intake was located below the perforated interval and relied primarily on gravity separation, permitting the gas to escape from the fluids prior to the fluid entering the pump intake, therefore, creating highly reliable pump output and predictable pumping efficiencies. In contrast, complex wellbores with long build and horizontal sections result in mixed multi-phase flow conditions being present at the pumping system intake. Therefore, the pump systems are challenged by the mixed phase flow at their intake, which can result in a gas lock condition of the pump. The mixed phases present at the pumping system intake require that the pumping system is equipped with provisions to maintain their efficiency in fluid pumping even in the presence of gas which may, at times, occupy the entire volume of the pump barrel. A rod pumping application is known to have cyclical pressure conditions which are a function of the reciprocating nature of the normal rod pumping operation. There is an approximate three order magnitude difference in the specific gravities of the gas phase when compared to the liquid phase. During conditions of high gas content, it is possible that the maximum compressed gas pressure in the pump is not sufficiently large enough to overcome the tubing fluid head pressure above the traveling valve ball and seat seal, which will likely result in the pump becoming gas locked. Existing solutions for gas lock mitigation in rod pumping systems are dependent upon inducement of artificial conditions such as friction, mechanical impact, and/or gas compression to instigate gas lock mitigation. These solutions suffer from well-known limitations and disadvantages. There remains a need in the art for a reciprocating rod pump system which can efficiently operate in a complex wellbore and deal with mixed phase flow with high gas content. SUMMARY OF THE INVENTION Embodiments of the present invention relate to a pump system which is passively responsive to a condition when a compressible gas is dominant in the pump barrel and may automatically adjust the pump configuration to compensate. Therefore, in one aspect, disclosed is a non-locking actuator system, for attachment to a traveling valve and disposed within a pump barrel defining a pump barrel volume, comprising: (a)a ported seat plug configured to attach to a distal end of a traveling valve cage, and defining a port allowing fluid communication from the pump barrel volume to a central chamber which is open to the traveling valve when attached to the traveling valve;(b)an intake section having a housing attached to a distal end of the ported seat plug and defining an interior volume, the intake housing defining at least one radial port for allowing fluid communication from the pump barrel volume into the non-locking actuator;(c)a pressure cylinder attached to a distal end of the intake housing and defining an internal activation chamber;(d)a distal inlet/outlet assembly connected to a distal end of the pressure cylinder and having a specific gravity valve closing a distal end of the activation chamber, the specific gravity valve comprising a specific gravity element having a specific gravity between that of a gas and a liquid, such that the speci