Reclosable toe valve with mechanical override

Abstract

A toe valve system positioned along a tubing string. The toe valve system a piston sleeve slidably disposed in an outer housing which has ports therethrough. The toe valve system comprises a shifting sleeve shiftable between positions with respect to the ports. A piston sleeve initially held in a position closing off the at least one port to prevent flow between the interior and exterior of the tubing string. A compensator sleeve mounted within the outer housing, wherein the compensator sleeve is free floating and can accommodate changes in tubing pressure. A piston chamber filled with a liquid which is located between the piston sleeve, the compensator sleeve and the outer housing. The liquid in the piston chamber is retained by a rupture disk that can release the liquid when sufficient pressure is applied within the toe valve system causing the piston sleeve to move and opening the ports.

Description

DOCKET NO.: IS24.1411-WO-PCTRECLOSABLE TOE VALVE WITH MECHANICAL OVERRIDEPriority Claim / Cross Reference to Related Applications

[0001] Patent Document claims priority under 35 U.S.C. § 119 to U.S. Provisional App.Ser. No. 63 / 701,790, entitled “Reclosable Toe Valve with Mechanical Override”, filed onOctober 1, 2024, which is incorporated herein by reference in its entirety.Background

[0002] In a variety of downhole well applications, a toe valve may be positioned along a casing string to enable selective communication between a wellbore and the surrounding reservoir via circumferential flow ports. In a multistage stimulation, for example, a toe valve may be run in at the toe of the casing in a closed position. The toe valve is then actuated to open the circumferential flow ports to provide communication between the interior of the casing and the surrounding reservoir. This allows an operator to run perforation guns, plugs, and other tools via wireline in a horizontal section of the wellbore by pumping fluids down through the casing string. The pumped fluids effectively push the tool or tools along the wellbore before exiting the casing through the flow ports of the toe valve. In some subsequent operations, such as sand control, there is a need to sequentially open and close the toe valve multiple times.Summary

[0003] A system and method of providing a multicycle valve system, e.g. a multicycle toe valve system, which may be positioned along a tubing string, e.g. casing string, and actuated multiple times as desired. According to an embodiment, a multicycle toe valve system comprises a piston sleeve slidably disposed in an outer housing which has at least one port therethrough. The toe valve system also may comprise a piston sleeve shiftable between positions with respect to the at least one port. The piston sleeve may initially beDOCKET NO.: IS24.1411-WO-PCT held in a position closing off the at least one port to prevent flow between the interior and exterior of the tubing string. The piston sleeve is held in this closed position by a temporary retention mechanism. The temporary retention mechanism can be a detent, shearing device or any other temporary holding device. The toe valve system also may comprise a compensator sleeve. The compensator sleeve can move to accommodate changes in tubing pressure or fluid expansion in the piston chamber. The toe valve system also may comprise a piston chamber vacuum filled with oil and shared between a compensator piston and the piston sleeve. The compensator piston is free floating. An increase in an inner diameter pressure of the tubing string, causes the free-floating pressure balance piston to move and compensator the tubing pressure with the oil pressure in the piston chamber. This prevents the piston sleeve from shifting prematurely The oil in the piston chamber is communicated to a pressure sensitive communication device such as a rupture disk.

[0004] To open the toe valve the tubing pressure is increased to above the rupturing pressure of the disk. The compensator piston will bottom out and contact a shoulder ring. Once ruptured the disk allows the oil to migrate from the piston chamber to a dump chamber. The dump chamber is vacuumed or filled with a compressible matter such as air at atmospheric pressure. The dump chamber receives the entirety of the oil from the piston chamber. The increased tubing pressure will now act on the sleeve piston allowing the piston sleeve overcomes the temporary retention mechanism. When the retention mechanism releases, the hydraulic piston shifts fully until it reaches the end of its travel opening the flow ports in the process. Subsequently, a mechanical shifting sleeve can close and reopen the flow ports multiple times.

[0005] The disclosure herein generally involves a system and methodology providing improved control of fluid flow between an interior and an exterior of a tubing string, e.g. improved communication between a wellbore and a surrounding reservoir. A toe valve system positioned along the tubing string although the multicycle valve system may have other configurations and may be used in other types of operations. As described in greater detail below, a pressure increases along the interior of the tubing string above the amount of pressure that the compensator piston can accommodate is used to initially activate theDOCKET NO.: IS24.1411-WO-PCT toe valve system and open one or more flow ports, thus allowing radial flow between an interior and an exterior of the tubing string.

[0006] Many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.Brief Description of the Drawings

[0007] In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that that embodiments of the present disclosure may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.

[0008] Figure l is a cross-sectional illustration of an example of a multicycle valve system in the form of a toe valve system positioned along a tubing string and deployed in a borehole, e.g. a wellbore, according to an embodiment of the disclosure.

[0009] Figure 2 is a cross-sectional illustration similar to that of Figure 1 but showing the toe valve system in an operational position after the piston sleeve has shifted, according to an embodiment of the disclosure.

[0010] Figure 3 is a cross-sectional illustration similar to that of Figure 2 but showing the toe valve system in a different operational position after mechanical shifting sleeve has shifted, according to an embodiment of the disclosure.

[0011] Figure 4 is an illustration of an example of the burst disc, according to an embodiment of the disclosure.

[0012] Figure 5 is an illustration of an example of the piston sleeve, according to an embodiment of the disclosure.Detailed DescriptionDOCKET NO.: IS24.1411-WO-PCT

[0013] In the specification and appended claims: the terms “connect,” “connection,” “connected,” “in connection with,” “connecting,” “couple,” “coupled,” “coupled with,” and “coupling” are used to mean “in direct connection with” or “in connection with via another element.” As used herein, the terms “up” and “down,” “upper” and “lower,” “upwardly” and “downwardly,” “upstream” and “downstream,” “uphole” and “downhole,” “above” and “below,” and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe some embodiments of the disclosure.

[0014] FIG. 1 illustrates a toe valve system 20. The toe valve system 20 is a type of multicycle valve system disposed along a tubing string. In the illustrated example, the tubing string can be in the form of a casing string or a liner string. The tubing string is positioned within a borehole, e.g. a wellbore. The borehole is drilled into a surrounding reservoir, and the toe valve system 20 controls fluid communication between a bore of the tubing string borehole and the surrounding reservoir. In other words, the toe valve system 20 may be operated to control fluid flow between an interior and an exterior of the tubing string when the tubing string is positioned within the borehole. Depending on the parameters of specific operations, the size, components, and materials used in the construction of tubing string, as well as toe valve system 20, may be changed or adjusted.

[0015] As shown in FIG. 1, the toe valve system 20 comprises an outer housing 22 having at least one port 24 to enable fluid flow between an interior and an exterior of the toe valve system 20. Additionally, the at least one port 24 may comprise a plurality of ports 24 which allow fluid flow between the interior and exterior of the toe valve system 20 and thus between the interior and exterior of the tubing string. In some embodiments, the plurality of ports 24 may be oriented in a generally radial direction through the outer housing 22 and may be arranged along a circumference of the outer housing 22. In some embodiments, the outer housing 22 may comprise a plurality of outer housings sections. A shroud 26 a may surround burst disk 28 within the housing. The shroud 26 allows for insertion of the burst disk 28 within the outer housing 22. A dump chamber 30 may be formed with the outer housing 22. The shroud 26 may surround portions of a top sub 32. In the embodiment illustrated, the top sub 32 is connected, e.g. threadedly connected, to an upper end of theDOCKET NO.: IS24.1411-WO-PCT outer housing 22. A bottom sub 34 is connected, e.g. threadedly connected, to a lower end of the outer housing 22. The upper sub 32 and bottom sub 34 may be used to connect the toe valve system 20 into the overall tubing string.

[0016] The toe valve system 20 may comprise piston sleeve 36 slidably mounted within the outer housing 22. The piston sleeve 36 is a sliding sleeve that is hydraulically actuated by tubing pressure. The piston sleeve 36 closes the ports 24 in a run in position. The piston sleeve 36 may comprise a plurality of seals 38 located about its circumference and oriented to form a sealing engagement with the interior surface of outer housing 22. In FIG. 1, the piston sleeve 36 is illustrated in a closed position in which the piston sleeve 36 is located so as to cover the ports 24 with seals 38 located on both sides of ports 24 thus preventing flow therethrough. The piston sleeve 36 may be held in a run in closed position covering the ports 24 via a temporary retention mechanism. The temporary retention mechanism can be a detent 40, shearing device or any other temporary holding device. The current embodiment utilizes the detent 40, which is illustrated in FIG. 1. The detent 40 is located on outer surface of the piston sleeve 36. An inner surface of the outer housing will have a lower groove 42 and an upper groove 44. The detent 40 will attach to the lower groove 42 in the run-in position until a requisite amount of tubing pressure is applied. The run-in position of the piston sleeve 36 is known as the first position. Once a requisite amount of tubing pressure is applied the piston sleeve 36 will shift and the detent 40 will attach to the upper groove 44 in the inner surface of the outer housing 22 placing the piston sleeve 36 in an operational position allowing flow through the ports 24 as shown in FIG. 2.

[0017] The toe valve system 20 comprises a shifting sleeve 46 slidably mounted within the outer housing 22 for movement between positions opening and closing the ports 24. The shifting sleeve 46 may comprise a plurality of seals 48 located about its circumference and oriented to form a sealing engagement with an interior surface of the outer housing 22. The shifting sleeve 46 is mechanically actuated. The shifting sleeve 46 is moved by a shifting tool (not shown). The shifting tool will connect to a profile. On the shifting sleeve 46. The profile is located on the inner surface of the shifting sleeve 46. The shifting sleeve 46 may be used to close and open the ports 24 after the piston sleeve 36 has been moved to the operational position as shown in FIG. 2. FIG. 3 illustrates the shifting sleeve in a closedDOCKET NO.: IS24.1411-WO-PCT position preventing flow through the ports 24 after the shifting sleeve 46 has been moved by the shifting tool.

[0018] Additionally, the toe valve system 20 has a compensator sleeve 48. The compensator sleeve 48 is a free floating piston that acts to pressure balance a piston chamber 52. On the outer surface of the compensator sleeve 48 is a seal 50 that seals with the inner surface of the outer housing 22. Furthermore, on the inner surface of the piston sleeve 36 is a seal that creates a seal with the outer surface of the compensator sleeve 48. The compensator sleeve 48 is pressure balanced and isolated from the flow ports 24. A chamber 52 is created between the compensator sleeve 48, the inner surface of the outer housing 22 and temporary secured piston sleeve 36. The piston chamber 52 is filled with a non-compressible fluid such as oil. The piston chamber 52 has an upper section 56 and a lower section 58 separated by a shoulder ring 54. The shoulder ring 54 creates a lower stop for the compensator sleeve 48. The shoulder ring 54 has three openings. One opening is fluidly connected to the upper section 56. A second opening fluidly connected to the lower section 58 and a third opening connected to a burst disk section 60 of a piston chamber 52. The free floating compensator piston 48 can move linearly due to changes in tubing pressure while the toe valve system 20 runs down hole. As the toe valve system 20 is run downhole the oil within the upper section 56 and the lower section 58 of the piston chamber 52 expands and contracts. When the oil expands the compensator sleeve 48 will move according to adjust to the change in temperature of the oil. As the oil expands the compensator sleeve 48 will move towards the top sub increasing the area of the upper section 56. The compensator sleeve 48 can also move due to changes in tubing pressure. As long as the changes in tubing pressure are below the pressure needed to overcome the retention mechanism such as the detent 40, the piston sleeve 36 will be compensated by the compensator sleeve 48. Meaning the piston sleeve 36 will remain stationary while the compensator sleeve 48 move towards the top sub increasing the area of the upper section 56 and reducing the area in the lower section 58.

[0019] Referring back to the rupture disk 28 which is illustrated in FIG. 4. The rupture disk 28 has no elastomeric seals. The rupture disk 28 is connected via two metal -to-metal gas tight connectors 62. The rupture disk 28 connectors are pressure testable for ease ofDOCKET NO.: IS24.1411-WO-PCT installation and reconfiguration of the rupture disk 28. The rupture disk 28 is a temporary valve that is pressure sensitive. Once the disk 28 is ruptured fluid will be able to enter the atmospheric chamber.

[0020] To open the valve the tubing pressure is increased to above the pressure needed to move the piston sleeve 36. The increased tubing pressure will cause the compensator sleeve 48 to contact the shoulder ring 54. Contacting the shoulder ring 54 will prevent further movement of the compensator sleeve 48. The increased pressure will act on the bottom of the piston sleeve 36. The bottom of the piston sleeve 36 has multiple castellations 64 as shown in FIG. 5. The castellations 64 are notches on a bottom face of the piston sleeve 36 creating a space between the piston sleeve 36 and shifting sleeve 46. The castellations 64 allow fluid pressure to act on the bottom of the piston sleeve. The oil from the piston chamber 52 will flow into the burst disk section 60 of the chamber rupturing the rupture disk 28. Once ruptured the disc allows the oil to migrate from the piston chamber 52 to a dump chamber 30. The dump chamber 30 is vacuumed or filled with a compressible matter, i.e. air at atmospheric pressure, to receive the entirety of the oil from the piston chamber 52.

[0021] Increasing the tubing pressure causes the compensator sleeve 48 to move first followed by the piston sleeve 36. The free-floating compensator sleeve 48 shifts until the free-floating compensator piston 48 reaches the end of its travel by contacting the shoulder ring 54. Once the compensator piston 48 has stopped moving the pressure will overcome the retention mechanism causing the piston sleeve 36 to move.

[0022] Once the piston sleeve 36 has been shifted. The toe valve system 20 is opened and fluid can flow through the ports 24 as illustrated in FIG. 2. The toe valve system 20 can be closed by mechanically shifting sleeve 46 with the shifting tool. The shifting sleeve 46 may be shifted between closed positions blocking flow through ports 24 and open positions allowing flow through ports 24 as many times as desired for a given operation. To shift the shifting sleeve 46 between closed and open positions, the shifting tool will engage an inner profile of the shifting sleeve 46. Suitable engagement with shifting tool enables shifting of the shifting sleeve 46 in either direction along the interior of outer housing 22.DOCKET NO.: IS24.1411-WO-PCT

[0023] Once the oil migrates to the dump chamber 30, the free-floating compensator piston shifts until the free-floating compensator piston reaches the end of its travel, causing the piston chamber oil pressure to further decrease until the force acting on the hydraulic piston overcomes the temporary retention mechanism. When the retention mechanism releases, the hydraulic piston shifts fully until the hydraulic piston reaches the end of its travel opening the flow ports in the process. Combining a compensator piston and a hydraulic piston in this manner eliminates most of the frictional forces in the initial activation process making the opening very accurate.

[0024] Separating the compensator piston 48 and the sleeve piston 36 allows for a more reliable shifting away from debris and cement since the compensator piston and the sleeve piston slide into one another as opposed to scraping debris along exposed seal bores. Separating the compensator piston 48 and the sleeve piston 36 eliminates most of the frictional forces in the initial activation process making the opening very accurate. Additionally, having the compensator piston and the hydraulic piston separate allows for mechanical override.

[0025] Within the outer housing 22 is a recess 68 on the inner surface. The recess 68 has an increase in the inner diameter. The purpose of the recess is to prevent sealing of the compensator piston 48 in the event of a mechanical override. The combination the compensator piston 48 and the piston sleeve 36 allows for mechanical override in the event the toe valve fails to open due to a malfunction of the rupture disk 28.. If mechanical override is needed, the shifting tool can connect with the shifting sleeve 46. A mechanical force can be applied to the shifting tool causing the shifting sleeve 46, sleeve piston 36 and the compensator sleeve 48 to shift. The mechanical force will cause the shifting sleeve 46, the piston sleeve 36 and compensator piston 48 to move towards the rupture disk. The compensator piston 48will be adjacent to the recess 68 in the inner surface of the inner housing. The upper seals surrounding the compensator piston 48 will no longer seal against the inner surface of the outer housing due to the increased diameter in the inner surface. This will create a fluid path for the oil to vent allowing the shifting sleeve 46, the piston sleeve 36 and the compensator sleeve 48 to shift in an uphole direction and eliminate the risk of hydraulic lock. In an alternative embodiment, the inner housing 22 can be extendedDOCKET NO.: IS24.1411-WO-PCT eliminating the need for a recess 68. Instead of venting the oil, the upper section 56 of the piston chamber 52 between the compensation piston 48 and inner housing 22 is increased in volume to accommodate all of the oil in the piston chamber 52. In the event of a mechanical override in this embodiment, the shifting sleeve 46, the sleeve piston 36 and the compensator sleeve 48 will be able to slide uphole while the compensator sleeve can slide even further uphole creating a larger chamber to accommodate the oil.

[0026] Although a few embodiments of the disclosure have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.

Claims

DOCKET NO.: IS24.1411-WO-PCTCLAIMSWhat is claimed is:

1. A reclosable toe valve comprising: an outer housing having at least one port to enable fluid flow between an interior and an exterior of a tubing string; a shifting sleeve slidably mounted within the outer housing for movement between positions opening and closing the at least one port; a piston sleeve slidably mounted within the outer housing for movement between positions closing and opening the at least one port; a compensator sleeve mounted within the outer housing, wherein the compensator sleeve is free floating; a chamber system having an atmospheric chamber connected with a piston chamber via a passageway initially blocked by a rupture member, the piston chamber initially containing a liquid and being located between the piston sleeve, the compensator sleeve and the outer housing to provide a pressure balance between an interior and an exterior of the piston sleeve while the piston sleeve is in a position closing the at least one port, wherein sufficient application of pressure within the tubing string and against the piston sleeve causes the rupture member to rupture and to thus allow flow of the liquid from the liquid chamber to the atmospheric chamber as the piston sleeve is shifted to a position opening the at least one port.

2. The reclosable toe valve of claim 1, wherein the compensator sleeve can move to accommodate changes in tubing pressure or fluid expansion in the piston chamber.

3. The reclosable toe valve of claim 1, wherein the rupture member comprises a rupture disk.

4. The reclosable toe valve as recited in claim 1, wherein the liquid comprises an oil.

5. The reclosable toe valve of claim 1, wherein the piston sleeve is held in the closed position blocking the least one port by a temporary retention mechanism.DOCKET NO.: IS24.1411-US-PSP6. The reclosable toe valve as recited in claim 1, wherein the shifting sleeve can move between positions opening and closing the at least one port multiple times with a shifting tool.

7. The reclosable toe valve as recited in claim 1, wherein the at least one radial port comprises a plurality of ports oriented to enable radial flow through the outer housing, the plurality of ports being arranged along the circumference of the outer housing.

8. The reclosable toe valve as recited in claim 1, wherein the reclosable toe valve has a mechanical override that allows the valve to actuate in the event the rupture member is inoperative.

9. A system for use in a well, comprising: a tubing string having a toe valve system disposed along the tubing string to control fluid flow between an interior and an exterior of the tubing string when the tubing string is positioned in a borehole, the toe valve system comprising: an outer housing having at least one port to enable fluid flow between an interior and an exterior of a tubing string; a shifting sleeve slidably mounted within the outer housing for movement between positions opening and closing the at least one port; a piston sleeve slidably mounted within the outer housing for movement between positions closing and opening the at least one port; a compensator sleeve mounted within the outer housing that is free floating; a chamber system having an atmospheric chamber connected with a piston chamber via a passageway initially blocked by a rupture member, the piston chamber initially containing a liquid and being located between the piston sleeve, the compensator sleeve and the outer housing to provide a pressure balance between an interior and an exterior of the piston sleeve while the piston sleeve is in a position closing the at least one port, wherein sufficient application of pressure within the tubing string and against the piston sleeve causes the rupture member to rupture and to thusDOCKET NO.: IS24.1411-US-PSP allow flow of the liquid from the liquid chamber to the atmospheric chamber as the piston sleeve is shifted to a position opening the at least one port.

10. The system of claim 9, wherein the compensator sleeve can move to accommodate changes in tubing pressure or fluid expansion in the piston chamber.

11. The system of claim 9, wherein the rupture member comprises a rupture disk12. The system as recited in claim 9, wherein the liquid comprises an oil.

13. The system of claim 9, wherein the piston sleeve is held in the closed position blocking the least one port by a temporary retention mechanism.

14. The system as recited in claim 9, wherein the shifting sleeve can move between positions opening and closing the at least one port multiple times with a shifting tool.

15. The system as recited in claim 9, wherein the at least one radial port comprises a plurality of ports oriented to enable radial flow through the outer housing, the plurality of ports being arranged along the circumference of the outer housing.

16. The system as recited in claim 9, wherein the reclosable toe valve has a mechanical override that allows the valve to actuate in the event the rupture member is inoperative.

17. A method of operating a reclosable toe valve system, comprising: positioning a toe valve along a tubing string to enable fluid communication between an interior and an exterior of the tubing string via at least one port; closing off the at least one port with a piston sleeve; using a liquid temporarily trapped in a piston chamber to secure the piston sleeve at the position closing off the at least one port while also pressure balancing the piston between an interior of the tubing string and the piston chamber; accommodating increased pressure in the tubing string or expansion of fluid in the piston chamber with a compensator sleeve; andDOCKET NO.: IS24.1411-US-PSP selectively releasing the liquid to enable shifting of the piston sleeve to a position allowing flow through the at least one port.

18. The method as recited in claim 17, further comprising providing the toe valve system with a shifting sleeve having features engageable by a shifting tool to enable repeated shifting of the shifting sleeve to positions blocking or not blocking the at least one port.

19. The method as recited in claim 17, wherein selectively releasing comprises pressuring up an interior of the tubing string until the piston sleeve causes the liquid to rupture a rupture disk and to flow into an atmospheric chamber.

20. The method of claim 17, wherein the toe valve has a mechanical override that allows the valve to actuate in the event the rupture member is inoperative.

Images