Expandable well barrier

Abstract

A method of shutting in a well bore includes positioning a plug having a tubular portion in the well bore. At least a portion of the tubular portion is radially plastically deformed into substantially sealing engagement with the wall of the well bore to substantially block flow through the well bore.

Description

BACKGROUND

The present invention relates to well tools, and more particularly, to well tools used for substantially sealing against passage of fluids through a well bore.

There are times over the life of a well during which the well will be temporarily or permanently shut-in. For example, a producing well may be temporarily shut-in for work over, lack of a market for the well's production, or for other reasons. When a well is abandoned, it is shut-in as part of abandoning the well. In the past, bridge plugs have been used to shut-in wells. However, it due to their complexity, bridge plugs are not inexpensive and have a potential for failure. Therefore, there is a need for a simpler device for shutting-in a well.

SUMMARY

The invention is directed to well tools for substantially sealing against passage of fluids through a well bore.

In one aspect, a method includes positioning a plug having a tubular portion in a well bore. At least a portion of the tubular portion is radially plastically deformed into substantially sealing engagement with the wall of the well bore to substantially block flow through the well bore.

In some instances, the tubular portion includes one or more circumferential seals adapted to substantially sealingly engage with the wall of the well bore. Radially plastically deforming the tubular portion may, in some instances, include applying a radial force to an interior of the tubular portion, for example by moving an expansion mandrel through at least a portion of the tubular portion. In some instances, the plug includes a tubular body with a transverse barrier member affixed thereto.

In an other aspect, a method of shutting in a well bore includes moving a mandrel through a tubular body to expand at least a portion of the tubular body into a wall of the well bore. The tubular body is coupled to a transverse barrier member. Passage of flow through the well bore is substantially sealed using the tubular body in the transverse member.

In some instances, the mandrel is withdrawn from the well bore after the tubular body is expanded. Moving the mandrel through the tubular body may plastically deform at least a portion of the tubular body.

In yet another aspect, a device for installation in a well bore includes a tubular body expandable into engagement with a wall of the well bore. A transverse barrier member is coupled to the tubular body to substantially prevent passage of fluids through the tubular body.

In some instances one or more circumferential seal members are provided about the tubular body and are adapted to substantially seal against the wall of the well bore when the tubular body is expanded. One or more circumferential ring members may be provided on the tubular body and adapted to prevent lateral extrusion of the seal members. The transverse barrier member may be affixed to the tubular body. The tubular body may be adapted to be plastically deformed into engagement with the wall of the well bore.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features of the invention will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic side cross-sectional view of an expandable well barrier positioned in a well bore in accordance with the concepts described herein.

FIG. 2 is a schematic partial side cross-sectional view of the expandable well barrier of FIG. 1 prior to being expanded in a well bore in accordance with the concepts described herein.

FIG. 3 is a schematic partial side cross-sectional view of the expandable well barrier of FIG. 1 expanded in a well bore in accordance with the concepts described herein.

FIG. 4 is a schematic partial side cross-sectional view of an alternative expandable well barrier having a receptacle for receiving a flow restriction in accordance with the concepts described herein.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

Referring first to FIG. 1, a well bore 10 extends from a surface 12 through one or more subterranean zones 14. Although, the well bore 10 is depicted as being substantially vertical in FIG. 1, the entire well bore 10 or portions thereof may deviate to be slanted, curved, substantially horizontal or otherwise not vertical. One or more casings 16 or other liners or tubing may be provided within the well bore 10. The casing 16 may extend wholly through the well bore 10 or may leave a portion of the well bore 10 as an open hole. In some instances, the casing 16 may be omitted from the well bore 10.

An illustrative expandable plug or well barrier 20 is depicted expanded in the well bore 10. When expanded, the illustrative expandable well barrier 20 sealingly or substantially sealingly engages the interior of the casing 16 to seal against passage of fluid between the casing 16 and the expandable well barrier 20. The illustrative expandable well barrier 20 also frictionally engages or otherwise grips the wall of the well bore 10 (e.g. the interior of the casing 16) to support both the weight of the expandable well barrier 20 and any components coupled to the expandable well barrier 20, as well as support a specified pressure differential across the expandable well barrier 20. In one instance, the specified pressure differential is selected based on the maximum pressure differential expected to be sealed by the expandable well barrier 20 when shutting-in a well plus a safety factor. In one instance, the specified pressure differential is the difference between atmospheric pressure and the shut-in pressure plus a safety factor.

The illustrative expandable well barrier 20 can be positioned at various locations in the well bore 10. FIG. 1 depicts the illustrative expandable well barrier 20 positioned near the end of the casing 16; however, in other instances, the illustrative expandable well barrier 20 may be positioned closer to the surface 12, or may partially overlap the end of the casing 16 and extend out into the open hole portion of the well bore 10. The location of the illustrative expandable well barrier 20 will depend on how much of the well bore 10 is desired to be shut-in. For example, if it is desired to shut-in the entire well bore 10, the illustrative expandable well barrier 20 will be installed near the surface 12. If it is desired to shut-in the well bore 10 below a specified subterranean zone 14, the illustrative expandable well barrier 20 will be positioned above the specified subterranean zone 14, and may be positioned immediately above the specified subterranean zone 14. Also, although discussed herein as gripping and sealing with the casing 16, in some instances, the expandable well barrier 20 can be configured to sealingly engage and/or grip other surfaces in the well bore 10. For example, the expandable well barrier 20 can be configured to sealingly engage and grip a liner that depends from the casing 16, another tubular in the well bore 10, or an open hole portion of the well bore 10.

Turning now to FIG. 2, the illustrative expandable well barrier 20 includes a substantially tubular body portion 22 and a blind end portion 26. Although depicted in FIG. 2 as having a substantially circular cross-section prior to expansion, the tubular body portion 22 can have other cross-sections. For example, in other embodiments the tubular body portion 22 can be corrugated with longitudinal or spiral axially oriented corrugations or circumferentially oriented corrugations, otherwise folded, or non-circular in cross-section. The blind end portion 26 is defined by a transverse barrier member 27 that spans the tubular body portion 22 to substantially prevent passage of fluid through the interior of the tubular body portion 22. In the illustrative expandable well barrier 20 of FIG. 2, the blind end portion 26 is affixed to the tubular body portion 22, for example by welding substantially around its perimeter, a threaded coupling, by being expanded into sealing engagement with the tubular body portion 22, or by being integrally formed (e.g. cast or forged) with the tubular body portion 22. In other instances, the end portion 26 need not be blind. For example, a transverse barrier member 27 may be provided (welded, threadingly coupled, or otherwise affixed) about a middle or other portion of the tubular body portion 22. In another example, the tubular body portion 22 may include a receptacle 40 (FIG. 4), such as a polished bore receptacle, latching device, profile or other provisions, for sealingly receiving a plug, a valve or other partial or complete flow restriction 42 that can be coupled to the expandable well barrier 20 on the surface or while the expandable well barrier 20 resides downhole.

The tubular body portion 22 includes one or more circumferential seals 24 (three shown) on its exterior configured to substantially seal with the casing 16 and substantially prevent passage of fluid between the illustrative expandable well barrier 20 and the casing 16. In some instances, one or more of the seals 24 may be an elastomeric material. In some instances, the one or more circumferential seals 24 are configured to form a gas tight seal. Circumferential ridges 28 may be provided to extend on either or both sides of one or more of the seals 24 and be configured to substantially prevent axial (relative to the tubular body portion 22) extrusion of the seals 24 as they are compressed into the casing 16. In some instances, the circumferential ridges 28 operate to support the seals 24 and enable sealing at higher pressures than without such support. Additionally, the ridges 28 aid in forming a gas tight seal by eliminating most if not all axial extrusion of the seals 24 and enabling use of a more supple seal material. FIG. 2 depicts ridges 28 position on both sides of each of the seals 24. In some instances, some or all of the ridges 28 may be configured to protrude into, and locally deform, the surface of the casing 16 to grip the casing 16. The ridges 28 may also be provided apart from the circumferential seals 24 or may be omitted.

The tubular body portion 22 is configured to receive an expander tool within. Although there are numerous configurations of expander tools that can be used according to the concepts described herein, an illustrative expander tool 30 depending from a working string 50 is depicted in FIG. 2. The illustrative expander tool 30 includes an expansion mandrel 32. The expansion mandrel 32 is sized to radially, plastically deform the tubular body portion 22 to a transverse dimension (e.g. diameter) at which the seals 24 substantially seal against the interior of the casing 16 when the expansion mandrel is passed through the interior of the body portion 22. If the body portion 22 is provided with ridges 28 that are adapted to protrude into the interior surface of the casing 16, the expansion mandrel 32 deforms the body portion 22 so that the ridges 28 protrude into and grip the interior surface of the casing 16.

In one instance, the outer transverse dimension (e.g. diameter) of the expansion mandrel 32 is larger than the inner transverse dimension (e.g. diameter) of the portion of the tubular body portion 22 that is to be expanded. The tubular body portion 22 may include a cone launcher 34, having a larger transverse dimension (e.g. diameter) than other portions of the tubular body portion 22. The transverse dimensions of the cone launcher 34 are selected to receive the expansion mandrel 32. In one instance, the cone launcher 34 is constructed by pre-expanding a portion of the tubular body portion 22 to accept the expansion mandrel 32. In another instance, the cone launcher 34 is constructed by machining the inner transverse dimension of the tubular body portion 22 to accept the expansion mandrel 32. In either instance, the cone launcher 34 can be constructed apart from and later coupled to the remainder of the tubular body portion 22 or constructed together with the remainder of the tubular body portion 22.

In the illustrative expandable well barrier 20, the cone launcher 34 resides about the upper end (left end in FIG. 2) of the tubular body portion 22. In some instances, the cone launcher 34 may include a sloped transition 36 between the larger interior transverse dimension of the cone launcher 34 and the smaller interior transverse dimension of the tubular body portion 22. The expansion mandrel 32 may include a corresponding sloping profile 38 on its leading edge configured to nest in the sloped transition 36. The sloping profile 38 additionally aids in smoothly expanding the tubular body portion 22 as the expansion mandrel 32 is moved axially through the tubular body portion 22.

The illustrative expander tool 30 may also include one or more extendable/retractable dogs 44. The dogs 44 are extendable to engage a downward facing shoulder 46 of the illustrative expandable well barrier 20. When engaged to the shoulder 46, the dogs 44 support the weight of the illustrative expandable well barrier 20 and the illustrative expandable well barrier 20 can be lowered into the well bore 10 supported on the illustrative expander tool 30. The dogs 44 additionally support the reaction force necessary to drive the expansion mandrel 32 through the tubular body portion 22 and expand the tubular body portion 22. When the dogs 44 are retracted to release from the shoulder 46, the illustrative expander tool 30 can be withdrawn from the illustrative expandable well barrier 20.

The illustrative expander tool 30 can be operated to drive the expansion mandrel 32 from the cone launcher 34 into the remainder of the tubular body portion 22 to expand at least a portion of the tubular body portion 22. In one instance, the sloping profile 38 of the expansion mandrel 32 substantially seals against the sloped transition 36 of the cone launcher 34, and the expansion mandrel 32 is driven through the tubular body portion 22 by pressure applied in the annulus between the casing 16 and the exterior of the illustrative expander tool 30. In other instances, expansion mandrel 32 may be moved through the tubular body portion 22 by hydraulic pressure applied through the interior of the illustrative expander tool 30 and/or mechanical force applied through the working string 50 (e.g. by pushing the expansion mandrel 32 through the tubular body portion 22 with the working string 50).

FIG. 3 depicts the illustrative expandable well barrier 20 in a set state. The expansion mandrel 32 has been passed through the interior of the tubular body portion 22 to expand the tubular body portion 22 into the casing 16 such that the seals 24 substantially seal against the wall of the well bore 10. The expandable well barrier 20 additionally grips the casing 16 the well bore 10, frictionally with the seals 24, and/or with the ridges 28.

In operation, the expander tool 30 is received in the interior of the expandable well barrier 20. The expansion mandrel 32 resides in the cone launcher 34 and the dogs 44 of the expander tool 30 are extended to engage the shoulder 46 of the expandable well barrier 20. In one instance, the expander tool 30 is received within the expandable well barrier 20 while the expandable well barrier 20 resides at the surface 12. The expandable well barrier 20 is then lowered into the well bore 10 on the expander tool 30, with the expander tool 30 coupled to the working string 50. Thereafter, the expandable well barrier 20 is lowered to the desired location within the well bore 10. The expansion mandrel 32 is actuated to move through and radially, plastically deform at least a portion of the tubular body portion 22. As the illustrative expandable well barrier 20 is radially, plastically deformed, the circumferential seals 24 come into sealing engagement with the casing 16 and substantially seal against passage of fluid between the illustrative expandable well barrier 20 and the casing 16. If so configured, the circumferential ridges 28 protrude into and grip the casing 16. Alternately, or in cooperation with the ridges 28, the circumferential seals 24 frictionally grip the casing 16. Thereafter, the illustrative expandable well barrier 20 substantially prevents passage through the well bore 10 past the expandable well barrier 20. The dogs 44 of the expander tool 30 may be retracted to release the expander tool 30 from the illustrative expandable well barrier 20, and the expander tool 30 can be withdrawn from the well bore 10. In some instances, it may be desirable to install a cement plug (not specifically shown) in the well bore 10 above the expanded well barrier 20.

The operations above can be repeated to install multiple expandable well barriers 20 in a well bore 10. For example, it may be desirable to install multiple expandable well barriers 20 in a well bore 10 if a previously installed in expandable well barrier 20 is found to be leaking. In another example, it may be desirable to install multiple expandable well barriers 20 in a well bore 10 to sequentially isolate multiple subterranean zones 14.

An advantage of one or more of the illustrative implementations described herein is that the expandable well barrier has few or no moving parts. Accordingly, it is inexpensive to construct, which is desirable for a device that, in some instances, will remain in the well bore indefinitely. Also, because there are few or no moving parts there is a lower likelihood of failure, as compared to a bridge plug with multiple moving parts, especially during setting the expandable well barrier in a well bore. Additionally, the installed expandable well barrier can easily be defeated by milling or drilling out the transverse barrier member and/or the tubular body portion.

A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.

Claims

1. A method, comprising:

positioning a plug having a tubular portion in a well bore; and

radially plastically deforming at least a portion of the tubular portion into substantially sealing engagement with a wall of the well bore to substantially block flow through the well bore.

2. The method of claim 1 wherein the tubular portion further comprises one or more circumferential seals adapted to substantially sealingly engage with the wall of the well bore.

3. The method of claim 2 wherein one or more of the seals is adapted to form a substantially gas tight seal with the wall of the well bore.

4. The method of claim 1 wherein the wall of the well bore comprises at least one of a liner, a tubing and a casing.

5. The method of claim 1 wherein radially plastically deforming the tubular portion comprises applying a radial force to an interior of the tubular portion.

6. The method of claim 1 wherein radially plastically deforming the tubular portion comprises moving an expansion mandrel through at least a portion of the tubular portion.

7. The method of claim 1 wherein the plug comprises a tubular body with a transverse barrier member affixed thereto.

8. The method of claim 7 wherein the transverse blocking member is a blind end.

9. A method of shutting-in a well bore, comprising:

radially expanding at least a portion of a tubular body into contact with a wall of the well bore, the tubular body coupled to a transverse barrier member; and

substantially sealing against passage of flow through the well bore using the tubular body and transverse barrier member.

10. The method of claim 9 further comprising moving a mandrel through the tubular body to radially expand at least a portion of the tubular body.

11. The method of claim 10 wherein moving the mandrel through the tubular body comprises plastically deforming at least a portion of the tubular body.

12. The method of claim 9 wherein the tubular body comprises one or more circumferential seals about its exterior.

13. The method of claim 9 wherein the wall of the well bore comprises at least one of a liner, a casing, and a tubing.

14. The method of claim 10 wherein moving a mandrel through the tubular body comprises moving the mandrel having a larger exterior transverse dimension than an interior transverse dimension of the at least a portion of the tubular body that is expanded.

15. A device for installation in a well bore, comprising:

a tubular body adapted to be radially expanded into substantially sealing engagement with a wall of the well bore; and

a transverse barrier member coupled to the tubular body to substantially prevent passage of fluids through the tubular body.

16. The device of claim 15 further comprising one or more circumferential seal members about the tubular body adapted to substantially seal against the wall of the well bore when the tubular body is expanded.

17. The device of claim 16 wherein one or more of the circumferential seal members are adapted to form a substantially gas tight seal with the wall of the well bore.

18. The device of claim 16 further comprising one or more circumferential ring members adapted to prevent lateral extrusion of at least one of the seal members.

19. The device of claim 15 wherein the transverse barrier member is affixed to the tubular body.

20. The device of claim 15 wherein the tubular body is adapted to be plastically deformed into engagement with the wall of the well bore.

21. The device of claim 15 wherein the tubular body is expandable into engagement with the wall of the well bore by moving an expansion mandrel in an interior of the tubular body.