Pump for inflating a downhole element, method, and system

Abstract

A pump for inflating a downhole element, including a housing having an inlet and an outlet, a piston disposed within the housing, a reversing lead screw in the housing, and a drive operably connected to the reversing lead screw. A method for setting a downhole element, including rotating a reversing lead screw, reciprocating a piston in a piston chamber with the reversing lead screw, drawing fluid into the piston chamber with movement of the piston in a first direction and expelling fluid from the chamber with movement of the piston in an opposite direction, and directing the expelled fluid to the downhole element. A borehole system, including a borehole in a subsurface formation, a string in the borehole, and a pump for inflating a downhole element, disposed within or as a part of the string.

Description

PUMP FOR INFLATING A DOWNHOLE ELEMENT, METHOD, AND SYSTEMCROSS REFERENCE TO RELATED APPLICATIONSThis application claims the benefit of U.S. Application No. 18 / 631326, filed on April 10, 2024, which is incorporated herein by reference in its entirety.BACKGROUND

[0001] In the resource recovery and fluid sequestration industries the setting of seals in the downhole environment is ubiquitous. Such seals include inflatable seals, which naturally require inflation. Reliable inflation apparatus is difficult to achieve. The art will well receive inflation apparatus that reliably and efficiently inflates seals as needed.SUMMARY

[0002] An embodiment of a pump for inflating a downhole element, including a housing having an inlet and an outlet, a piston disposed within the housing, a reversing lead screw in the housing, and a drive operably connected to the reversing lead screw.

[0003] An embodiment of a method for setting a downhole element, including rotating a reversing lead screw, reciprocating a piston in a piston chamber with the reversing lead screw, drawing fluid into the piston chamber with movement of the piston in a first direction and expelling fluid from the chamber with movement of the piston in an opposite direction, and directing the expelled fluid to the downhole element.

[0004] An embodiment of a borehole system, including a borehole in a subsurface formation, a string in the borehole, and a pump for inflating a downhole element, disposed within or as a part of the string.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:

[0006] Figure 1 is a sectional view of the pump for inflating a downhole element as disclosed herein in a fluid drawn position;

[0007] Figure 2 is a sectional view of the pump for inflating a downhole element as disclosed herein in a fluid expelled position; and

[0008] Figure 3 is a view of a borehole system including a pump for inflating a downhole element as disclosed herein.DETAILED DESCRIPTION

[0009] A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.

[0010] Referring to Figures 1 and 2, a pump for inflating a downhole element 14 is illustrated in cross section in a position where fluid has been drawn into the tool (FIG. 1) and a position where the drawn in fluid has been expelled from the pump 10. The pump 10 is configured to reciprocate between the positions illustrated in Figure 1 and 2 to draw fluid into a piston chamber 12 and expel fluid from the piston chamber 12. The fluid when expelled is conveyed to a downhole element 14 (schematically illustrated) that may be a bridge plug or other inflatable. Fluid may be so conveyed with reciprocal movement of the pump 10 until the downhole element 14 is inflated to a threshold pressure. In embodiments, that pressure that is preselected and can be verified through an amperage draw that indicates the threshold pressure or through a pressure sensor device.

[0011] Pump 10 includes a housing 16 having an inlet 18. The inlet 18 optionally may include a filter 20 and may include a one-way valve 22 such as a check valve to allow fluid flow in a direction into the piston chamber 12 and prevent flow of fluid out of the chamber 12 through the inlet 18. Housing 16 also includes an outlet 24 that may include a one-way valve 26, such as a check valve, to prevent fluid expelled from the chamber 12 from moving back into chamber 12. The housing will further include a port 28 that allows fluid communication between an inside area of the housing 16 and an annulus 30 outside of the housing 16.

[0012] Disposed with the housing 16 is a reversing lead screw 32 supported by a thrust bearing 34 and a centralizer 36. The centralizer 36 includes openings 38 to allow free fluid movement therethrough to avoid the creation of a hydraulic head. The lead screw 32 is connected to a drive 40 to rotate the lead screw in a consistent direction. In some embodiments, the drive 40 may include a gear train 42 to modify produced torque to suit the particular application. A piston 44 is disposed telescopically with the lead screw 42 and is driven by the lead screw 42 through a blade or nut 46 disposed in the piston 44 and in operable contact with a groove 48 of the lead screw 42. Piston 44 includes a seal 50 so that hydraulic pressure may be generated in the chamber 12 with movement of the piston 44 to reduce the volume of the chamber 12. Piston 44 also, in some embodiments, will include an alignment groove 52 that interacts with a key 54 fixedly disposed in the housing 16. It will be understood that the groove could also be on the housing 16 and the key 54 on the pistonwith the same effect of preventing rotation of the piston 44 while permitting axial movement of the piston 44.

[0013] During use, the drive 40, which may be an electric motor, a hydraulic motor, etc., rotates the screw 42, which causes the piston 44 to cycle to the right or left in the figures (the left position being depicted in Figure 1 and the right position being depicted in Figure 2). The movement is self-reversing and the piston will continuously draw fluid through inlet 18 into chamber 12 when moving to the position of Figure 1 and then expel that fluid through outlet 24 to the downhole element 14 when moving to the position of Figure 2. Various elements 14 may take more or fewer cycles of piston 44 to reach a selected threshold pressure. Once the selected threshold pressure is reached however, the downhole element 14 may be released and the pump 10 may be withdrawn to surface or other destination. An indication that the threshold pressure has been reached may be obtained simply through a pressure gauge or may be obtained through drive amperage draw. As will be appreciated, amperage draw in an electric motor will rise as the motor works harder against some impediment. In this case, the drive 40 is urging the piston 44 against the rising hydraulic pressure in the element 14. Amperage will naturally increase as the pressure in element 14 increases. The specific pressure threshold for a particular element 14 can be mapped to a particular amperage or range of amperage to give a signal at surface that the element 14 is inflated. At this point, the element 14 should be released. An additional data point that can be obtained is that the amperage of drive 40 will immediately fall once the element 14 has been released because the pump 10 is merely circulating fluid in the annulus and not building pressure. This will confirm that the element 14 has been successfully released.

[0014] Referring to Figure 3, a borehole system 60 is illustrated. The system 60 comprises a borehole 62 in a subsurface formation 64. A string 66 is disposed within the borehole 62. A pump 10 as disclosed herein is disposed within or as a part of the string 66.

[0015] Set forth below are some embodiments of the foregoing disclosure:

[0016] Embodiment 1: A pump for inflating a downhole element, including a housing having an inlet and an outlet, a piston disposed within the housing, a reversing lead screw in the housing, and a drive operably connected to the reversing lead screw.

[0017] Embodiment 2: The pump as in any prior embodiment, wherein the piston includes a reversing lead screw follower.

[0018] Embodiment 3: The pump as in any prior embodiment, wherein the follower is a nut.

[0019] Embodiment 4: The pump as in any prior embodiment, wherein the follower is a blade.

[0020] Embodiment 5: The pump as in any prior embodiment, wherein the drive is a motor.

[0021] Embodiment 6: The pump as in any prior embodiment, further including an antirotation key disposed between the piston and the housing.

[0022] Embodiment 7: The pump as in any prior embodiment, wherein the inlet includes a filter.

[0023] Embodiment 8: The pump as in any prior embodiment, wherein the inlet includes a one-way valve.

[0024] Embodiment 9: The pump as in any prior embodiment, wherein the outlet includes a one-way valve.

[0025] Embodiment 10: A method for setting a downhole element, including rotating a reversing lead screw, reciprocating a piston in a piston chamber with the reversing lead screw, drawing fluid into the piston chamber with movement of the piston in a first direction and expelling fluid from the chamber with movement of the piston in an opposite direction, and directing the expelled fluid to the downhole element.

[0026] Embodiment 11 : The method as in any prior embodiment, further including filtering fluid being drawn into the piston chamber.

[0027] Embodiment 12: The method as in any prior embodiment, further including driving the reversing lead screw with a motor.

[0028] Embodiment 13: The method as in any prior embodiment, wherein the drawing and expelling is continued until a threshold pressure is achieved in the downhole element.

[0029] Embodiment 14: The method as in any prior embodiment, wherein the threshold pressure is determined by amperage draw in a motor rotating the reversing lead screw.

[0030] Embodiment 15: The method as in any prior embodiment, further including releasing the downhole element.

[0031] Embodiment 16: The method as in any prior embodiment, further including verifying release by a experiencing reduction in amperage draw in a motor rotating the reversing lead screw subsequent to occurrence of an amperage draw consistent with the downhole element being inflated to a threshold pressure.

[0032] Embodiment 17: A borehole system, including a borehole in a subsurface formation, a string in the borehole, and a pump for inflating a downhole element as in any prior embodiment, disposed within or as a part of the string.

[0033] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms “about”, “substantially” and “generally” are intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application. For example, “about” and / or “substantially” and / or “generally” can include a range of ± 8% of a given value.

[0034] The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a borehole, and I or equipment in the borehole, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc.

[0035] While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited.

Claims

CLAIMSWhat is claimed is:

1. A pump (10) for inflating a downhole element (14), characterized by: a housing (16) having an inlet (18) and an outlet (24); a piston (44) disposed within the housing (16); a reversing lead screw (32) in the housing (16); and a drive (40) operably connected to the reversing lead screw (32).

2. The pump (10) as claimed in claim 1, wherein the piston (44) includes a reversing lead screw follower.

3. The pump (10) as claimed in claim 2, wherein the follower is a nut (48).

4. The pump (10) as claimed in claim 2, wherein the follower is a blade (46).

5. The pump (10) as claimed in claim 1, wherein the drive (40) is a motor.

6. The pump (10) as claimed in claim 1, further including an antirotation key(54) disposed between the piston (44) and the housing (16).

7. The pump (10) as claimed in claim 1, wherein the inlet (18) includes a oneway valve (22, 26).

8. The pump (10) as claimed in claim 1, wherein the outlet (24) includes a oneway valve (22, 26).

9. A method for setting a downhole element (14), characterized by: rotating a reversing lead screw (32); reciprocating a piston (44) in a piston chamber (12) with the reversing lead screw (32); drawing fluid into the piston chamber (12) with movement of the piston (44) in a first direction and expelling fluid from the chamber (12) with movement of the piston (44) in an opposite direction; and directing the expelled fluid to the downhole element (14).

10. The method as claimed in claim 9, further including filtering fluid being drawn into the piston chamber (12).

11. The method as claimed in claim 9, wherein the drawing and expelling is continued until a threshold pressure is achieved in the downhole element (14).

12. The method as claimed in claim 11 , wherein the threshold pressure is determined by amperage draw in a motor rotating the reversing lead screw (32).

13. The method as claimed in claim 9, further including releasing the downhole element (14).

14. The method as claimed in claim 13, further including verifying release by a experiencing reduction in amperage draw in a motor (40) rotating the reversing lead screw (32) subsequent to occurrence of an amperage draw consistent with the downhole element (14) being inflated to a threshold pressure.

15. A borehole system (60), characterized by: a borehole (62) in a subsurface formation (64); a string (66) in the borehole (62); and a pump (10) for inflating a downhole element (14) as claimed in claim 1 disposed within or as a part of the string (66).

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