SCREEN APPARATUS AND METHOD

Abstract

A downhole expandable apparatus for restricting ingress of solids in a wellbore comprises a base pipe, a fluid permeable expandable foam material mounted on the base pipe configurable between a non-expanded and an expanded configuration, and a retractable sleeve. The retractable sleeve is moveable between a first configuration in which the retractable sleeve retains the expandable foam material in the non-expanded configuration, and a second configuration in which the retractable sleeve is retracted to provide a free portion of the expandable foam material. The expandable foam material is permitted to radially expand towards the expanded configuration and into engagement with a surface in the wellbore.

Claims

1. A downhole expandable apparatus for restricting ingress of solids in a wellbore, comprising: a base pipe; a fluid permeable expandable foam material mounted on the base pipe configurable between a non-expanded and an expanded configuration; and a retractable sleeve moveable between a first configuration in which the retractable sleeve retains the expandable foam material in the non-expanded configuration, and a second configuration in which the retractable sleeve is retracted to provide a free portion of the expandable foam material to permit the expandable foam material to radially expand towards the expanded configuration and into engagement with a surface in the wellbore.

2. The downhole expandable apparatus according to claim 1, wherein the fluid permeable expandable foam material at least partially defines a filtration assembly.

3. (canceled)

4. The downhole expandable apparatus according to claim 1, comprising a flow channel extending axially along the apparatus.

5. The downhole expandable apparatus according to claim 1, wherein the base pipe comprises at least one aperture in a wall thereof.

6. The downhole expandable apparatus according to claim 5, wherein the base pipe comprises a plurality of apertures, and the plurality of apertures are substantially evenly spaced along the base pipe.

7. The downhole expandable apparatus according to claim 5, wherein the at least one aperture comprises a valve therein.

8. (canceled)

9. The downhole expandable apparatus according to claim 5, wherein the at least one aperture is positioned under the expandable foam material.

10. The downhole expandable apparatus according to claim 1, comprising a flow port for the introduction and/or removal of a fluid from the wellbore.

11. The downhole expandable apparatus according to claim 5, wherein the retractable sleeve prevents or restricts a flow of fluid through the at least one aperture in the base pipe when the retractable sleeve is in the first configuration.

12. The downhole expandable apparatus according to claim 1, wherein fluid flow through the expandable foam material is prevented or restricted when the expandable foam material is in the non-expanded configuration.

13. The downhole expandable apparatus according to claim 1, wherein the expandable foam material is mounted on the base pipe so as to fully circumscribe the base pipe.

14. The downhole expandable apparatus according to claim 1, wherein the expandable foam material is configured to the non-expanded configuration by compression under the retractable sleeve when the retractable sleeve is in the first position.

15. The downhole expandable apparatus according to claim 1, wherein the expandable foam material comprises an open-cell foam material.

16. The downhole expandable apparatus according to claim 1, wherein the expandable foam material has a varying coarseness.

17. The downhole expandable apparatus according to claim 16, wherein the expandable foam material has a graduated coarseness from a relatively coarse portion of expandable foam material, to a relatively fine portion of expandable foam material.

18. The downhole expandable apparatus according to claim 1, wherein the expandable foam material is provided in a single layer.

19. The downhole expandable apparatus according to claim 1, wherein the retractable sleeve is axially moveable between the first configuration and the second configuration.

20. The downhole expandable apparatus according to claim 1, wherein the retractable sleeve is detachable from the expandable apparatus.

21.-22. (canceled)

23. The downhole expandable apparatus according to claim 1, comprising a pump located downhole of the expandable foam material.

24. A method for restricting ingress of solids in a wellbore, comprising: positioning a downhole expandable apparatus in a wellbore, the downhole expandable apparatus including a fluid permeable expandable foam material held in a non-expanded configuration by a retractable sleeve; retracting the retractable sleeve to provide a free portion of expandable foam material, and permit the free portion of expandable foam material to radially expand towards an expanded configuration and into engagement with a surface in the wellbore.

25. A method for repairing/plugging a defect in a sand screen or tubular, comprising: positioning a downhole expandable apparatus in a wellbore adjacent a defect, the expandable apparatus comprising a base pipe and an expandable foam material mounted thereon, the expandable foam material being retained in a non-expanded configuration by a retractable sleeve; retracting the retractable sleeve of the downhole expandable apparatus to configure a portion of the expandable foam material to an expanded configuration, in which the expandable foam material is expanded so as to contact the defect.

26. A method for stabilising a subsurface formation, comprising: positioning a downhole expandable downhole apparatus in a wellbore adjacent a subsurface formation, the expandable apparatus comprising a base pipe and an expandable foam material mounted thereon, the expandable foam material being retained in a non-expended configuration by a retractable sleeve; retracting the retractable sleeve of the downhole expandable apparatus to configure a portion of the expandable foam material to an expanded configuration, in which the expandable foam material is expanded so as to contact the subsurface formation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0078] FIG. 1 is a cross-sectional view of an expandable apparatus.

[0079] FIG. 2 is an enlarged view of region 2 of FIG. 1.

[0080] FIG. 3 is an enlarged view of region 3 of FIG. 1.

[0081] FIG. 4 is an enlarged view of region 4 of FIG. 1.

[0082] FIG. 5 illustrates the expanded configuration of the apparatus of FIG. 1.

[0083] FIGS. 6 to 9 show a sequence of steps of an installation of the apparatus of FIG. 1.

[0084] FIGS. 10 and 11 show detail of a further example of the expandable apparatus.

[0085] FIG. 12 is a schematic illustration of an exemplary expandable apparatus installed downhole.

[0086] FIG. 13 is a schematic illustration of a further exemplary expandable apparatus installed downhole.

DETAILED DESCRIPTION OF THE DRAWINGS

[0087] The present disclosure relates to an expandable apparatus in which an expandable foam material may be caused to expand so as to restrict the ingress of solids in a wellbore. The expandable apparatus may be defined as a filtration apparatus. The expandable apparatus may have multiple exemplary uses, some of which are described below.

[0088] An example of an expandable apparatus 10 is shown in FIG. 1. The expandable apparatus 10 is constructed of a plurality of parts, described below, that together define a base pipe. The expandable apparatus 10 defines a flow channel 12 that extends axially along the length of the expandable apparatus 10.

[0089] The expandable apparatus 10 is shown surrounded by a retractable sleeve 14, which in this example completely circumscribes the expandable apparatus 10. The retractable sleeve 14 terminates at an uphole end of the expandable apparatus 10 in a sleeve connector 16. In use, the sleeve connector 16 may be moved axially uphole relative to the expandable apparatus 10 so as to retract the retractable sleeve 14 from the expandable apparatus 10, as will be shown in the following Figures. In the example of FIG. 1, the sleeve connector 16 is connected, to tool 20, which may be a actuator tool (and the actuator tool may also be a running tool). As a result of the connection between the sleeve connector 16 and the actuator tool 20, movement of the actuator component in an axially uphole direction results in a similar axial uphole movement of the retractable sleeve 14, thereby removing the retractable sleeve 14 from the expandable apparatus 10.

[0090] Axially downhole, the apparatus 10 further comprises a centraliser 24, further detail of which can be seen in FIG. 2. The centraliser comprises a bow spring 24a which, in the example of FIG. 1, is held in a retracted position under the retractable sleeve 14. In the retracted position, the centraliser 24 is prevented from any engagement with an external surface by the retractable sleeve 14.

[0091] The apparatus further comprises a base pipe 26 having an expandable foam material 28 mounted thereon, more detail of which can be seen in FIG. 3. In this example, the base pipe 26 comprises a plurality of apertures 30, axially and circumferentially spaced along the base pipe 26 such that, in use, a fluid is able to flow into or out of the plurality of apertures 30. The expandable foam material 28 is mounted on an outer surface 32 of the base pipe 26. Although it is not shown in detail in FIG. 3, the skilled person will appreciate that the expandable foam material 28 may be mounted on the base pipe 26 by any suitable means, for example by chemical bonding e.g. through application of an adhesive. The expandable foam material is contained within an annulus formed between the retractable sleeve 14 and the base pipe 26, and in the example of FIGS. 1 and 3, the expandable foam material 28 is pressed against an inner surface of the retractable sleeve 14, which functions to hold the expandable foam material 28 in the non-expanded configuration. It should be noted that the expandable foam material 28 is mounted on the base pipe 26 such that it traverses each of the plurality of apertures 30 therein. As such, were a fluid containing particulate matter to be flowed through the expandable foam material 28, then the particulate matter would be prevented from entering the interior of the base pipe 26 by the expandable foam material 28, while the fluid portion (which may be a liquid, or a gas, or both) would be permitted to flow through the expandable foam material 28 and the plurality of apertures 30, and into the interior of the base pipe 26. In the example shown, the expandable foam material 28 is shown as a single sleeve surrounding the base pipe 26. It should, however, be noted that the expandable foam material 28 may be provided as multiple concentric sleeves. For example, the expandable foam material 28 may be provided as a first sleeve mounted on the base pipe, and a concentric second sleeve mounted on the first sleeve, the second sleeve being of greater diameter than the first sleeve. As such, the expandable foam material 28 may be provided on the base pipe 26 in the form of multiple cylindrical layers.

[0092] With the centraliser 24 in the retracted position and the expandable foam material 28 in the non-expanded configuration, FIGS. 1 to 3 illustrate the expandable apparatus 10 configured so as to enable running and positioning of the expandable apparatus 10 downhole.

[0093] Forming part of the expandable apparatus 10 is an anchor 36, more detail of which can be seen in FIG. 4. Shown in FIGS. 1 and 4, the anchor 36 is in a retracted position to facilitate running of the expandable apparatus 10 into a wellbore (not shown). The anchor 36 is configurable to an expanded position, shown in the following figures, which may permit the expandable apparatus 10 to engage an external surface (e.g. the inner surface of a casing, sand screen, pipe, or the like, in which the expandable apparatus 10 is positioned). To better grip an exterior surface, the anchor 36 is provided with a toothed profile 36a, as can be seen in FIG. 4. In the example shown in FIGS. 1 and 4, the anchor 36 is formed from a plurality of elongate members, arranged in pairs 38a, 38b. A view of one such pair 38a, 38b is shown most clearly in FIG. 4. As shown, each of the elongate members 38a, 38b is connected by a pin member 40, enabling rotation of a first elongate member 38a relative to a second elongate member 38b. In the retracted position, as shown in FIG. 4, the pair of elongate members 38a, 38b lie flat, such that their radially outer surface is generally in line with the radial outer surface of the surrounding expandable apparatus 10, and each of the axes of the elongate members 38a, 38b is generally aligned with that of the expandable apparatus 10.

[0094] It should be noted that the retractable sleeve 14 does not axially extend as far as the anchor 36, such that the anchor 36 is able to be operated regardless of the position of the retractable sleeve 14.

[0095] Axially adjacent and uphole of the anchor 36 is a sliding sleeve mechanism 40, which can be used to operate the anchor 36. The sliding sleeve mechanism 40 comprises an inner sleeve 42 and an outer sleeve 44, with a chamber 46 being located therebetween. A port 48 in the inner sleeve 42 allows fluid communication between the chamber 46 and the flow channel 12 in the interior of the expandable apparatus 10. The anchor 36 is positioned on an outer surface of the inner sleeve 42, while an end portion of the outer sleeve 44 abuts an axially uphole end of the elongate member 38a of the anchor 36.

[0096] In use, the port 48 may be exposed to a higher fluid pressure, the pressure communication between the port 48 and the chamber 46 also causing the pressure in the chamber 46 to rise. Such an increased pressure may be as a result of an increase in pressure in the flow channel 12 itself, or as a result of a pressure containing tool (e.g. the actuator tool 20) being positioned in pressure communication with the port 48.

[0097] A rise in pressure in the chamber 46 will cause a force to act on seal members 50a, 50b, positioned between the inner and outer sleeves 42, 44, thereby urging the inner and outer sleeves 42, 44 in opposing directions. In this example, the outer sleeve 44 is permitted to move in an axially downhole direction, relative to the inner sleeve 42. As the outer sleeve 44 is urged in a downhole direction, an axially directed force acts on the anchor 36. This causes rotation of the elongate members 38a, 38b relative to the pin 40, such that the elongate members form a V-shape that protrudes radially from the surface of the expandable apparatus 10 (best shown in FIGS. 8 and 9).

[0098] In FIG. 5 is shown an elevation view of an uphole section of the expandable apparatus 10, with the retractable sleeve (not shown) removed. As shown, with the retractable sleeve removed, the bow spring 24a of the centraliser 24 has sprung radially outwardly, such that, when positioned in a wellbore (not shown), the centraliser 24 would contact a surface of the wellbore to centre the expandable apparatus 10 therein.

[0099] Similarly, following the removal of the retractable sleeve, the expandable foam material 28 has expanded radially. In situ, the expandable foam material 28 would continue to expand until coming into contact with a surface in a wellbore. The expansion may be by a variety of mechanisms, for example by an elastic recovery effect of the foam material, following removal of radially inwardly directed compressive force applied by the retractable sleeve on the expandable foam material 28, or as a result of the exposed expandable foam material 28 being free to interact with wellbore fluids, thereby expanding the foam material 28.

[0100] FIGS. 6 to 9 illustrate one example of the installation of the expandable apparatus 10 of FIG. 1 in a wellbore 50.

[0101] In this example, a sand screen 52 has been installed in the wellbore 50, and the sand screen has developed a number of faults 54 therein, leading to the ingress of sand 56 into the interior of the sand screen 52. The faults 54 may have been caused by, for example, a hot spot on the sand screen 52, or by erosion of the sand screen 52.

[0102] The expandable apparatus 10 is run inside the sand screen 52, and lowered (e.g. on a completion string 58) to the location of the faults 54 in the sand screen. Once at the location of the faults 54, a flow of fluid (water, for example) can be flowed through the flow channel 12 of the apparatus. Although not shown, then apparatus may comprise a nozzle arrangement, such that the fluid exits the flow channel 12 of the expandable apparatus 10 as a jet, thereby assisting to cause rapid and turbulent flow inside the sand screen. Such flow may assist to entrain the sand that has been deposited inside the sand screen in the fluid. As the fluid is flowed into the sand screen, the tool may be moved in a downhole direction, as can be seen in FIGS. 6 and 7, entraining sand within the fluid flow as it is moved.

[0103] As can be seen in FIGS. 6 and 7, the retractable sleeve 14 is in the retracted configuration whereby the expandable foam material (not visible in FIGS. 6 and 7) is held thereunder. In this configuration, fluid flow through the apertures in the base pipe 26 is prevented by the retractable sleeve 14. Therefore, flow of a fluid through the flow channel 12 exits through the nozzle arrangement (not shown) and into an annulus 15 between the apparatus 10 and the sand screen 52. Once in the annulus, the flow of fluid can be used to suspend particulate matter therein, and be circulated to the surface via the annulus 15.

[0104] Once the sand has been cleared from the interior of the sand screen, the expandable apparatus 10 is positioned such that the expandable foam material 28 is positioned radially adjacent the faults 54 in the sand screen 52. Initially, the expandable foam material is contained beneath the retractable sleeve 14, and is not in contact with the sand screen 52. The retractable sleeve 14 is then axially retracted from the tool (as shown in FIGS. 8 and 9) to expose the expandable foam material 28.

[0105] However, before the retractable sleeve 14 may be retracted, the expandable apparatus 10 must be secured in position in the wellbore. To secure the apparatus 10 in the wellbore, an anchor 36 is moved from a retracted position to an expanded position, as described previously. In the expanded position, the anchor 36 protrudes radially so as to engage the sand screen 52. Once engaged with the sand screen 52, the anchor prevents axial movement of the expandable apparatus 12 in the wellbore 50.

[0106] Thereafter, the completion string 58 is able to be detached from the uphole end of the expandable apparatus 10, although maintaining a connection with the retractable sleeve 14. As axial movement of the expandable apparatus 10 is now prevented by the engagement of the anchor 36 with the sand screen, then uphole axial movement of the completion string 58 with the connected retractable sleeve 14 will have the effect of axially retracting the retractable sleeve 14 from the expandable apparatus 10.

[0107] As can be best seen in FIGS. 8 and 9, as the retractable sleeve is retracted from the expandable apparatus 10, the expandable foam material 28 expands radially outwardly, and into contact with the sand screen 52 so as to bridge the faults 54 therein. Similarly, a centraliser 24, located on a section of the expandable apparatus 12 that is uphole of the expandable foam material 28, radially expands from a retracted position to an extended positon, contacting an interior surface of the sand screen 52 and providing a centralising effect on the expandable apparatus 10.

[0108] Once in place the expandable foam material 28 of the expandable apparatus 10 bridges the faults 54 in the sand screen 52 so as to prevent ingress of sand therein, while continuing to permit the flow of a fluid therethrough. Once installed, the expandable apparatus 10 may remain in position for as long as production of a fluid into the sand screen is desired.

[0109] FIGS. 10 and 11 illustrate a further example of an expandable apparatus 10, having a valve incorporated into the apertures 30 of the base pipe 26.

[0110] For the sake of conciseness, a description of identical parts of the expandable apparatus 10 to those in FIGS. 1 to 5 will not be repeated. In this example, the expandable apparatus 10 comprises a base pipe 26 comprising a plurality of apertures 30, with an expandable foam material 28 mounted thereon so as to fill an annulus between the base pipe 26 and a retractable sleeve 14. Each of the plurality of apertures comprises a check valve 31, which permits the flow of a fluid in a radially outward direction. As with the example of FIGS. 1 to 5, the expandable foam material 28 bridges each of the plurality of apertures 30.

[0111] In this example, a fluid may be flowed through a fluid channel 12 of the expandable apparatus, and through the check valves 31 provided in the base pipe 26. The flow of fluid may then pass through the expandable foam material 28 and into a wellbore. As such, in this example, the expandable apparatus may be used to inject fluid into a wellbore, whilst simultaneously providing a plugging effect of a crack, aperture, fissure, or the like in a sand screen, tubing, pipeline etc. in a wellbore, so as to prevent ingress of particulate material therein (for example, during breaks in the injection of a fluid into a wellbore).

[0112] FIG. 12 is a schematic diagram of through-tubing 362 with an expandable apparatus 310 installed in a sand screen 352 in a wellbore 350. Schematically illustrated, the apparatus 310 essentially comprises a base pipe 326 having a plurality of apertures therein 330. An expandable foam material 328 is mounted on the base pipe 326, and bridges each of the plurality of apertures 330. An anchor 336 is positioned below the expandable foam material 328, and is used to hold the expandable apparatus 310 in place relative to the sand screen 352, as in previous examples. Similarly, a centraliser 324 is provided uphole of the expandable foam material 328 to centralise the expandable apparatus 310 in the wellbore 350. In this example, the expandable foam material 328 bridges a large defect 354 in the sand screen 352. Uphole of the expandable apparatus 310 is a through-tubing 362, held in position by packers 364, which may be used for receiving a fluid produced in through the sand screen 352 in the wellbore, or may be used to provide an injection fluid to the expandable apparatus 310.

[0113] With the retractable sleeve (not shown) in the retracted configuration, the expandable apparatus 310 is of a diameter that it is able to be installed via through-tubing 362, and subsequently expanded and installed against the sand screen 352.

[0114] FIG. 13 illustrates a further use of an example of an expandable apparatus 410. In this example, the expandable apparatus 410 is positioned in an open hole wellbore 450, radially adjacent a shale formation containing seams of coal 468, the seams of coal being impregnated with methane gas. The example shown in FIG. 13 contains some similarities to that described in FIGS. 1 to 5. As such similar reference numerals have been used for similar parts, augmented by 400.

[0115] In contrast to the previous examples, wherein the expandable apparatus is run in to a wellbore having an existing sand screen in place, in this example the expandable apparatus 410 may form part of a completion string that is run into and installed in an open-hole section of wellbore, for example before initial production operations in the wellbore begin. In this example the expandable apparatus 410 may be run into a wellbore on a tooling string, and maintain a connection with said tooling string throughout production in the wellbore.

[0116] As can be seen in FIG. 13, and as was the case with previous examples, the apparatus 410 comprises a base pipe 426, having an expandable material 428 mounted thereon. It should be noted that, in this example, the base pipe is simply a blank pipe, and does not comprise any apertures, as was the case with the previous examples. In this case, the length of the expandable material is selected so as to be approximately the same depth as the shale formation, adjacent to which the expandable apparatus 410 is positioned. As such, when the expandable foam material 428 is in the expanded configuration as shown, it expands so as to be in contact with the surrounding shale formation 450 along substantially the entire depth of the shale formation 450.

[0117] In a further example, it may be possible to stack multiple apparatuses in a wellbore, so as to provide expandable foam material along the entire depth of the shale formation 450. Further, although in the example of FIG. 13 contact between the expandable foam material 428 is shown along the entire depth of the shale formation 450, examples where there are gaps in the contact between the expandable foam material and the shale formation 450 are equally possible. For example, as long as expandable foam material is present at the top and bottom of the shale formation 450, so as to contain particulate matter in the shale formation 450, the apparatus may be able to function.

[0118] While, in this example, it may be possible to secure the expandable apparatus 410 in place with an anchor (not shown), as in the previous examples, as the expandable apparatus 410 maintains a connection with the tooling string, an anchor may not be necessary. Instead, the expandable apparatus 410 may be held in place by the tooling string, the tooling string being held in place by any appropriate means, for example by packers.

[0119] In this example, the expandable apparatus 410 comprises a pump 470 located axially downhole of the expandable foam material 428.

[0120] In use, the expandable apparatus 410 is positioned adjacent the shale formation with a retractable sleeve (not shown in this example) positioned over the expandable foam material 428, with the expandable foam material 428 being in the non-expanded configuration. As with previous examples, once in the desired position, the retractable sleeve is retracted and the expandable foam material 428 expanded to be in contact with the surrounding shale formation 450.

[0121] After the retractable sleeve has been retracted, the pump 470 can be operated to pump any fluid in the wellbore through an inlet 472, and through a flow channel in the base pipe (not shown) towards the surface of the wellbore. Typically, shale formations may produce large volumes of fluid, e.g. water. Where seams of coal are included in the shale formation, methane gas may also be produced, along with large quantities of shale rock. Having the expandable foam material 428 of the expandable apparatus 410 in contact with the shale formation may prevent or reduce the production of shale from the formation, while permitting the production of fluids, for example water and/or methane. As such, the expandable foam material 428 may assist to stabilise subsurface formations, such as shale formations, which may otherwise release particulate matter into the wellbore.

[0122] Reducing the production of particulate matter (e.g. shale) from the formation may be beneficial for the operation of pump 472. In particular, where there is intermittent operation of pump 472, particulate matter (such as shale) may settle on the pump while it is not in use. Such large volumes of shale can make it difficult to restart the pump 472 without cause significant damage. Therefore the apparatus may prolong the lifespan of the pump 472, as it may reduce the choking of the pump by produced particulate matter.

[0123] With the pump 472 in operation, liquids (e.g. water) from the formation 450 may flow through the expandable foam material 428 and proceed in a downhole direction, towards pump 472 in the direction of arrows 480, through the flow channel of the expandable apparatus 410 and towards the surface of the wellbore. As the liquids are produced, gas (e.g. methane) may also be produced. By virtue of its lighter density, the produced gas will tend to flow upwards in the direction of arrows 482, and will remain in an annulus between the expandable apparatus 410 and the wellbore 450. For illustrative purposes, the produced gas is shown exiting the expandable foam material 428 in the form of bubbles 453 exiting from the upwardly located surface of the expandable foam material 428.

[0124] Uphole of the expandable apparatus 410 is located a section of casing 484, which can be used to collect the produced gas in the annulus.