Sliding valve downhole pump
Downhole pumps for producing hydrocarbons and/or other fluids from a well bore include a barrel having a plunger or plunger valve disposed therein and a stationary valve engaged with the barrel. The valve(s) include(s) an outer housing and an inner piston movable within the outer housing. Responsive to movement of the plunger or plunger valve relative to the barrel, the inner piston(s) is(are) movable between a first position that permits fluid flow through the valve and a second position that prevents fluid flow therethrough.
Embodiments usable within the scope of the present disclosure relate, generally, to downhole pumps and methods for producing a well, e.g. through a secondary recovery process.
In the detailed description of various embodiments of the present invention presented below, reference is made to the accompanying drawings, in which:
Embodiments of the present invention are described below with reference to the listed Figures.
DETAILED DESCRIPTION OF THE EMBODIMENTSBefore describing selected embodiments of the present invention in detail, it is to be understood that the present invention is not limited to the particular embodiments described herein. The disclosure and description herein is illustrative and explanatory of one or more presently preferred embodiments of the invention and variations thereof, and it will be appreciated by those skilled in the art that various changes in the design, organization, order of operation, means of operation, equipment structures and location, methodology, and use of mechanical equivalents, as well as in the details of the illustrated construction or combinations of features of the various elements, may be made without departing from the spirit of the invention.
As well, the drawings are intended to describe the concepts of the invention so that the presently preferred embodiments of the invention will be plainly disclosed to one of skill in the art, but are not intended to be manufacturing level drawings or renditions of final products and may include simplified conceptual views as desired for easier and quicker understanding or explanation of the invention. As well, the relative size and arrangement of the components may differ from that shown and still operate within the spirit of the invention as described throughout the present application.
Moreover, it will be understood that various directions such as “upper,” “lower,” “bottom,” “top,” “left,” “right,” “uphole,” and “downhole,” and so forth are made only with respect to explanation and clarity in conjunction with the drawings, and that the components may be oriented differently, for instance, during transportation and manufacturing as well as operation. Because many varying and different embodiments may be made within the scope of the inventive concept(s) herein taught, and because many modifications may be made in the embodiments described herein, it is to be understood that the details herein are to be interpreted as illustrative and non-limiting.
Embodiments usable within the scope of the present disclosure relate, generally, to downhole pumps, including both insertion pumps and tubing pumps, and methods for producing hydrocarbons and other fluids (e.g., water, drilling fluids, and/or carbon dioxide or other gasses) from a well bore, that utilize a smaller number of moving parts than conventional pumps, thereby reducing wear and decreasing the potential for vapor locking of the valves, while providing for an improved flow capacity.
A conventional downhole pump (e.g. an insertion or tubing pump) includes at least two ball check valves, which open and close in alternating fashion, though various existing downhole pumps can include as many as six or more valves. Each valve, seat, and sealing surface of these pumps are prone to wear and failure, requiring frequent repair and/or replacement. Also, when gas is produced from the well bore simultaneously with liquid, it is common for the gas to become trapped in the pump, preventing the build up of fluid pressure necessary to continue actuating the valves (e.g. known as gas or vapor locking). Additionally, the flow capacity of an insertion pump is limited by the diameter and configuration of the pump, which must be sized to pass through a production conduit as a single unit, and by the limited flow capacity of the ball valves. As a result, insertion pumps may be insufficient for production of wells where a significant volume of fluid flow must be accommodated.
Referring now to
The standing valve (12) is shown having an inner piston (26) movable within an outer housing (28), e.g., between a first, closed position, shown in
The plunger valve (14) is similarly shown having an inner piston (36) movable within an outer housing (38) between a first, open position, shown in
During typical operations, the standing valve (12) and the plunger valve (14) will function in tandem, opening and closing in alternating fashion with each stroke of the plunger rod (20).
It should be understood that while the standing valve (12) and/or the plunger valve (14) can be actuated through fluid pressure at either end thereof, in various embodiments, the valves (12, 14) can be actuated through electrical, hydraulic, pneumatic, and/or mechanical means, or any similar method of actuation.
Referring now to
The inner piston (26) is shown having a central opening coincident with the bore (46) of the outer housing (28) to permit the passage of the outer housing (28) and slidable movement of the inner piston (26) therein. The inner piston (26) is also shown having one or more channels (34) for permitting fluid flow, and one or more sealing surfaces (48, 50) for abutting against the outer housing (28) to isolate the channels (34) from and/or place the channels (34) into communication with the inlet and outlet openings (30, 32), defining a fluid pathway through the standing valve (12). While the inner piston (26) is shown as a generally cylindrical structure, it should be understood that the inner piston (26) can have any shape or dimension able to fit within the outer housing (28), and can be formed as a unitary structure or a structure having multiple parts. Additionally, while the channels (34) are shown as flutes and/or notches, formed at the exterior of the inner piston (26), it should be understood that any number and type of channels, bores, slots, and/or orifices can be used to flow fluid through any portion of the inner piston (26). The inner piston (26) can be formed from any generally rigid materials suitable for use within a wellbore environment, such as metal, plastic, and/or one or more polymers or composites. In an embodiment, the material of the inner piston (26) can be selected based on the desired weight of the inner piston (26) and/or the desired fluid pressure necessary to move the inner piston (26) to open and/or close the standing valve (12). For example, the inner piston (26) can be formed from plastic to minimize weight and enable the standing valve (12) to be operated using a minimum of energy.
Referring now to
Referring now to
While
Referring now to
The inner piston (36) is shown having a central opening coincident with the bore (68) of the outer housing (38) to permit the passage of the outer housing (38) and slidable movement of the inner piston (36) therein. The inner piston (36) is also shown having one or more channels (44) for permitting fluid flow, and one or more sealing surfaces (70, 72) for abutting against the outer housing (38) to isolate the channels (44) from and/or place the channels (44) into communication with the intake and output openings (40, 42), defining a fluid pathway through the plunger valve (14). While the inner piston (36) is shown as a generally cylindrical structure, it should be understood that the inner piston (36) can have any shape or dimension able to fit within the outer housing (38), and can be formed as a unitary structure or a structure having multiple parts. Additionally, while the channels (44) are shown as flutes and/or notches, formed at the exterior of the inner piston (36), it should be understood that any number and type of channels, bores, slots, and/or orifices can be used to flow fluid through any portion of the inner piston (36). The inner piston (36) can be formed from any generally rigid materials suitable for use within a wellbore environment, such as metal, plastic, and/or one or more polymers or composites. In an embodiment, the material of the inner piston (36) can be selected based on the desired weight of the inner piston (36) and/or the desired fluid pressure necessary to move the inner piston (2636 to open and/or close the plunger valve (14). For example, the inner piston (36) can be formed from plastic to minimize weight and enable the plunger valve (14) to be operated using a minimum of energy.
Referring now to
The inner piston of the plunger valve may be of similar construction to that of the standing valve, depicted in
Referring now to
The outer housing (92) is shown having an inlet opening (102) at a first end thereof, and an outlet opening (104) at a second end thereof The outer housing (92) is further shown having an intake opening (100) in a side surface thereof The inner piston (90) is shown having flow channels (110) extending between ends thereof, a recession (106) formed in an outer surface thereof, and intake channels (108) extending from the recession (106) to the lower end of the inner piston (90). Upper and lower sealing surfaces (112, 114) shown on the inner piston (90) are usable to isolate the channels (108, 110) from the inlet and outlet openings (102, 104), depending on the position of the inner piston (90) within the outer housing (92).
Specifically,
Referring now to
Specifically,
During operation, the string of connecting members (126) (e.g., a string of sucker rods or similar connecting members) can be reciprocated using a pump jack or similar surface device, causing movement of the plunger (124) within the pump barrel (118). This movement can generate fluid pressure that causes the inner piston (90) to move in a manner that defines an inlet passage, as described previously, enabling the flow of fluid from the exterior of the valve (88) to flow into the pump barrel (118) along the flow path (128). During an upstroke of the plunger (124), the inner piston (90) is moved to define an outlet passage, as described previously, enabling the flow of fluid from the pump barrel (118) through the valve (88) and into the conduit (120) along the flow path (130).
It should be understood that while
Referring now to
As described previously, each stroke of the pump jack (130) and thereby, each stroke of the inner pistons (26, 36) can draw fluid from the exterior of the pump barrel (16) through the second valve and into the pump barrel (16), and from the pump barrel (16) through the first valve and into the conduit string (120), and move fluid upward through the conduit string (10). Also, as described above, it should be noted that reciprocation of the second valve can cause movement of one or both inner pistons (26, 36) independent of its placement or its movement relative to the first valve. As such, in alternate embodiments, the second valve could be disposed in an uphole direction relative to the first valve, and/or the second valve could be secured in a fixed position relative to the conduit string (10) while the pump barrel (16) and/or the first valve is reciprocated by the pump jack (130).
Additionally, while
Embodiments described herein thereby provide downhole pumps and methods having a minimum of moving parts, that can provide an improved flow capacity over that of conventional downhole pumps.
While various embodiments of the present invention have been described with emphasis, it should be understood that within the scope of the appended claims, the present invention might be practiced other than as specifically described herein.
Claims
1. A downhole pump for producing fluids from a well bore, the pump comprising:
- a stationary valve comprising an outer housing with an inlet opening and an outlet opening and an inner piston movable within the outer housing, wherein the inner piston includes a channel extending therethrough;
- a barrel engaged with the stationary valve; and
- a plunger valve disposed within the barrel and engaged with a connecting rod that extends through a bore in the stationary valve, wherein the plunger valve comprises a plunger housing with an intake opening and an output opening and a plunger piston movable within the plunger housing, wherein the plunger piston includes a plunger channel extending therethrough,
- wherein the inner piston is movable between a first position in which the channel is in communication with the inlet opening and the outlet opening to define a fluid pathway and a second position in which the channel is isolated from communication with at least one of the inlet opening and the outlet opening,
- and wherein the plunger piston is movable between an open position in which the plunger channel is in communication with the intake opening and the output opening to define a plunger fluid pathway and a closed position in which the plunger channel is isolated from communication with at least one of the intake opening and the output opening.
2. The downhole pump of claim 1, further comprising at least one securing member engaging the connecting rod, the plunger valve, or combinations thereof for retaining the plunger valve in a fixed position relative to the connecting rod.
3. The downhole pump of claim 1, wherein the outer housing of the stationary valve further comprises a securing member for retaining the outer housing of the stationary valve and the barrel in a fixed position for facilitating reciprocation of the plunger valve.
4. The downhole pump of claim 1, further comprising a securing member for retaining the plunger valve in a fixed position for facilitating reciprocation of the barrel.
5. The downhole pump of claim 1, wherein the lower end of the inner piston of the stationary valve comprises a sealing surface for isolating the outlet opening from the channel, the plunger piston comprises a sealing surface for isolating the output opening from the plunger channel, or combinations thereof.
6. A method for producing fluids from a well bore, the method comprising the steps of:
- lowering a downhole pump into the wellbore, wherein the downhole pump comprises a stationary valve engaged with a conduit and a barrel, and a plunger valve within the barrel, wherein the stationary valve comprises a standing housing and a standing piston, and wherein the plunger valve comprises a plunger housing and a plunger piston;
- causing movement of the plunger valve in a first direction relative to the barrel, thereby moving the plunger piston into an open position that enables flow of fluid through the plunger valve into the barrel and moving the standing piston into a closed position that prevents flow of fluid from the conduit into the barrel; and
- causing upward movement of the plunger valve in a second direction relative to the barrel, thereby moving the plunger piston into a closed position that prevents flow of fluid through the plunger valve and moving the standing position into an open position that enables flow of fluid from the barrel through the stationary valve and into the conduit.
7. The method of claim 6, wherein the step of lowering the downhole pump into the well bore comprises engaging a string of connecting members to the downhole pump and inserting the downhole pump through the conduit by extending successive joints of the string of connecting members into the well bore to position the downhole pump a selected position for production of fluid.
8. The method of claim 6, wherein the step of lowering the downhole pump into the well bore comprises engaging a securing member within the wellbore to retain the standing housing or the plunger housing in a fixed position relative to the conduit.
9. The method of claim 6, wherein the step of causing movement of the plunger valve in the first direction relative to the barrel, the step of causing movement of the plunger valve in the second direction relative to the barrel, or combinations thereof, comprises reciprocating a connecting member engaged with the downhole pump to cause movement of the plunger valve within the barrel, thereby displacing fluid to cause movement of the plunger piston and the standing piston.
10. The method of claim 6, wherein the step of causing movement of the plunger valve in the first direction relative to the barrel, the step of causing movement of the plunger valve in the second direction relative to the barrel, or combinations thereof, comprises reciprocating a connecting member engaged with the downhole pump to cause movement of the barrel about the plunger valve, thereby displacing fluid to cause movement of the plunger piston and the standing piston.
11. A downhole pump for producing fluid from a well bore, the pump comprising:
- a stationary valve;
- a barrel engaged with the stationary valve; and
- a plunger disposed within the barrel and engaged with a connecting rod extending through a bore in the stationary valve,
- wherein the stationary valve comprises an outer housing with an inlet opening and an outlet opening and an inner piston movable within the outer housing, wherein the inner piston includes a channel extending therethrough, and wherein the inner piston is movable between a first position in which the channel is in communication with the inlet opening and the outlet opening to define a fluid pathway and a second position in which the channel is isolated from communication with at least one of the inlet opening and the outlet opening; and
- wherein movement of the plunger relative to the barrel causes movement of the inner piston between the first position and the second position.
12. The downhole pump of claim 11, wherein the plunger comprises:
- a plunger valve having an outer housing and an inner piston movable within the outer housing, wherein the outer housing comprises a first end having an inlet opening and a second end having an outlet opening, wherein the inner piston comprises an upper end, a lower end, and a channel and a bore extending between the upper end and the lower end, wherein the inner piston is movable between a first position in which the channel is in communication with the inlet opening and the outlet opening to define a fluid pathway and a second position in which the channel is isolated from communication with at least one of the inlet opening and the outlet opening,
- wherein downward movement of the plunger relative to the barrel causes movement the inner piston of the plunger valve toward the first position and further causes movement of the inner piston of the stationary valve toward the second position, thereby permitting fluid flow into the barrel through the fluid pathway of the plunger valve while preventing fluid flow through the stationary valve, and
- wherein upward movement of the plunger relative to the barrel causes movement of the inner piston of the plunger valve toward the second position and further causes movement of the inner piston of the stationary valve toward the first position, thereby permitting fluid flow from the barrel through the fluid pathway of the stationary valve while preventing fluid flow through the plunger valve.
13. The downhole pump of claim 12, further comprising at least one securing member engaging the connecting rod, the plunger valve, or combinations thereof for retaining the plunger valve in a fixed position relative to the connecting rod.
14. The downhole pump of claim 12, wherein the outer housing of the stationary valve further comprises a securing member for retaining the outer housing of the stationary valve and the barrel in a fixed position for facilitating reciprocation of the plunger valve.
15. The downhole pump of claim 12, further comprising a securing member for retaining the plunger in a fixed position for facilitating reciprocation of the barrel.
16. The downhole pump of claim 12, wherein the lower end of the inner piston of the stationary valve, the lower end of the inner piston of the plunger valve, or combinations thereof, comprise a sealing surface for isolating the outlet opening from the channel.
17. The downhole pump of claim 11, wherein the outer housing of the stationary valve further comprises a side surface having an intake opening, wherein the inner piston further comprises an outer surface having a recession formed therein and in intake channel extending from the recession to the lower end of the inner piston,
- wherein downward movement of the plunger relative to the barrel causes movement of the inner piston within the outer housing to align the recession with the intake opening, thereby defining an intake passage from the intake opening through the intake channel and the inlet opening for permitting flow of fluid into the barrel, and
- wherein upward movement of the plunger relative to the barrel causes movement of the inner piston to define an outlet passage from the inlet opening through the channel and the outlet opening for permitting flow of fluid from the barrel through the stationary valve.
18. The downhole pump of claim 17, wherein the lower end of the inner piston comprises a sealing surface for engaging a surface of the second end of the outer housing to isolate the intake channel from the fluid pathway.
19. The downhole pump of claim 17, wherein the upper end of the inner piston comprises a sealing surface for engaging a surface of the first end of the outer housing to isolate the fluid pathway.
20. The downhole pump of claim 17, wherein the second end of the outer housing further comprises a securing member for retaining the outer housing and barrel in a fixed position for facilitating reciprocation of the plunger.
21. The downhole pump of claim 17, further comprising a securing member for retaining the plunger in a fixed position for facilitating reciprocation of the barrel.
22. A method for producing fluid from a well bore, the method comprising the steps of:
- engaging a valve with a barrel, wherein the valve comprises an outer housing and an inner piston movable within the outer housing, wherein the barrel comprises a plunger disposed therein, and wherein the plunger is engaged with a connecting member that extends through the barrel and valve;
- lowering the valve and the barrel through a conduit into the well bore;
- engaging the connecting member with a device adapted to impart motion to the connecting member;
- imparting motion to the connecting member to cause downward movement of the plunger relative to the barrel, thereby moving the inner piston to a first position that enables flow of fluid through the valve into the barrel; and
- imparting motion to the connecting member to cause upward movement of the plunger relative to the barrel, thereby moving the inner piston to a second position that enables flow of fluid from the barrel through the valve to the conduit.
23. The method of claim 22, wherein the step of engaging the valve with the barrel comprises threadably connecting a lower end of the outer housing to an upper end of the barrel.
24. The method of claim 22, wherein the step of lowering the valve and the barrel through the conduit into the well bore comprises extending successive joints of the connecting member into the well bore to position the valve and the barrel at a selected position for production of fluid.
25. The method of claim 22, wherein the step of lowering the valve and the barrel through the conduit into the well bore further comprises engaging a securing member within the wellbore to retain an upper end of the outer housing or the plunger in a fixed position relative to the conduit.
26. The method of claim 22, wherein the step of imparting motion to the connecting member comprises reciprocating the connecting member using the device disposed above the wellbore to cause movement of the plunger within the barrel, thereby displacing fluid to cause movement of the inner piston.
27. The method of claim 22, wherein the step of imparting motion to the connecting member comprises reciprocating the connecting member using the device disposed above the wellbore to cause movement of the barrel about the plunger, thereby causing displacement of fluid to impart movement to the inner piston.
Type: Application
Filed: Mar 28, 2011
Publication Date: Oct 4, 2012
Inventor: John E. Freeman (Big Spring, TX)
Application Number: 13/065,702
International Classification: F04B 53/12 (20060101); F04B 49/00 (20060101);