Tie-back sealing system of displacement sleeve

Abstract

The present disclosure relates to a displacement sleeve tie-back sealing system that may include a body portion and a swellable material disposed about a circumference of the body portion. The swellable material is configured to swell in response to exposure to wellbore fluid. Further, the system may include an upper end ring disposed in a position axially above the swellable material, a lower end ring disposed in a position axially below the swellable material, and a sleeve disposed radially outward from the swellable material in the lowered position and sealed against the upper end ring and / or the lower end ring to fluidly isolate the swellable material from a wellbore. The sleeve is configured to contact a downhole feature in a set position and contact with the downhole feature is configured to move the sleeve to expose the swellable material to wellbore fluid such that the swellable material expands to seal against a downhole tubing.

Description

Background Art

[0001] In some wellbore operations, one or more liner tiebacks may be lowered into the well. Liner tiebacks may be lowered into the well to improve the flow of produced fluids (e.g., hydrocarbons). That is, having a smaller diameter for the flow of produced fluids via a liner tieback may increase the flow rate of the produced fluid. Traditionally, liner tiebacks are sealed to the liner hanger downhole. However, for large-bore liner hangers, it is often challenging to obtain a reliable tieback seal because the relatively large diameter of the piston of the tieback sealing system may not be flush with the inner diameter of the liner hanger. To address this problem, non-piston tieback seals may instead be lowered into the well. Some of these tieback seals may be configured to expand in response to contact with wellbore fluids. Unfortunately, these tieback seals may expand prematurely in the wellbore (i.e., before reaching the liner hanger). BRIEF DESCRIPTION OF THE DRAWINGS

[0002] These drawings illustrate certain aspects of some of the embodiments of the present disclosure and are not intended to limit or define the methods.

[0003] Figure 1 A wellbore completion system according to some embodiments of the present disclosure is shown.

[0004] FIG. 2A to FIG. 2B A cross-sectional view of a displaced sleeve tieback seal according to some embodiments of the present disclosure is shown.

[0005] FIG. 3A to FIG. 3B A cross-sectional view of a displaced sleeve tieback seal system with a hydrostatic assist chamber according to some embodiments of the present disclosure is shown.

[0006] FIG. 4A to FIG. 4C A cross-sectional view of a displaced sleeve tieback sealing system sealing against a casing and a liner hanger is shown according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0007] A displaced sleeve tieback sealing system is disclosed herein, which is configured to form a seal with a corresponding liner hanger, a liner, and / or a casing positioned adjacent to the liner hanger. As described in detail below, the displaced sleeve tieback sealing system includes at least one sleeve covering a swellable packer material. In fact, the sleeve prevents fluid from the wellbore from contacting the swellable packer material so that the swellable packer material does not expand prematurely when the tool (e.g., the displaced sleeve tieback sealing system) is lowered into the well. When the tool reaches the corresponding liner hanger, liner, and / or casing, contact between the tool and the liner hanger and / or other downhole features having a suitable geometry can actuate the sleeve and expose the swellable packer material to the wellbore so that the swellable packer material can react and expand to form a seal (e.g., a tieback seal) at the corresponding liner hanger, liner, and / or casing adjacent to the liner hanger.

[0008] Figure 1 A wellbore completion system according to some embodiments of the present disclosure is shown. As shown, a wellbore completion system 100 may include a casing 102 (e.g., a casing string) disposed in a wellbore (e.g., a wellbore 104). Specifically, the casing 102 may be lowered into the well to a desired position during a completion operation. Once in place, the casing 102 may be cemented or otherwise fixed in place. The casing 102 may support the surrounding downhole formation 106 during a production operation. In addition, the casing 102 may provide a flow path along the wellbore 104 for the produced fluid (e.g., hydrocarbons). In addition, as shown, a liner 108 may be fixed to a downhole end 110 of the casing 102 via a liner hanger 112. That is, the liner 108 may be suspended from the casing 102 so that the liner 108 extends downhole from the downhole end 110 of the casing 102. The liner 108 may extend a flow path of the produced fluid (e.g., hydrocarbons) along the wellbore 104. During completion operations, produced fluids may flow upward through the liner 108, casing 102, and / or additional tubulars to the surface. The terms "liner," "casing," and "tubulars" are generally used to describe tubular wellbore items used for various purposes in wellbore operations. The liner 108, casing 102, and tubulars may be made of a variety of materials (metals, plastics, composites, etc.) that may or may not be extended as part of the installation process and may be segmented or continuous. The liner 108 or casing 102 need not be cemented in place. Furthermore, any type of liner, casing, or tubular may be used in accordance with the principles of the present invention.

[0009] In addition, a liner tieback 116 can be lowered into the well through the casing 102 to the liner hanger 112 and / or the liner 108 to help improve the flow of production fluids (e.g., hydrocarbons) through the casing 102 and / or other tubulars. Specifically, the liner tieback 116 can be sealed to the liner hanger 112, the liner 108, and / or the casing 102 adjacent to the liner hanger 112 so that production fluids flowing upward from the liner 108 can flow through the liner tieback 116 instead of through the casing 102. As shown, the liner tieback 116 has a smaller diameter than the casing 102, which can improve the flow of production fluids to the surface 118. In addition, the liner tieback 116 can be configured to be sealed to the liner hanger 112, the liner 108, and / or the casing 102 via a shift sleeve tieback sealing system 120 disposed at the lower end 122 of the liner tieback 116. As described in detail below, the displaced sleeve tieback seal system 120 includes at least one sleeve covered with a swellable material (eg, a swellable packer material) that expands (eg, expands) in response to exposure to a wellbore fluid. Figure 2A 104). The sleeve prevents wellbore fluid from contacting the swellable material so that the swellable material does not expand prematurely when a tool (e.g., a shift sleeve tieback seal system 120) is lowered into the well. When the tool 120 reaches the liner hanger 112, the liner 108, and / or the casing 102 adjacent to the liner hanger 112, contact between the tool 120 and the downhole feature (e.g., the liner hanger 112, the liner 108, and / or another feature having a suitable geometry) may actuate the sleeve and expose the swellable material to the wellbore 104 so that the swellable material may react and expand to form a seal (e.g., a tieback seal) at the liner hanger 112, the liner 108, and / or the casing 102 (e.g., a tieback seal). Figure 2B , Figure 3B and Figure 4C shown).

[0010] FIG. 2A to FIG. 2B sectional views of a displacement sleeve tieback sealing system in a run-in position and a set position, respectively, according to some embodiments of the present disclosure are shown. Figure 2AAs shown, the displacement sleeve tie-back sealing system 120 includes a body portion 200 (e.g., a cylindrical body) having a swellable material 202 disposed around the circumference of the body portion 200. Specifically, the swellable material 202 may be disposed between an upper end ring 204 and a lower end ring 206, each of which is disposed around the body portion 200. The upper end ring 204 may be positioned uphole from the lower end ring 206. In addition, the upper end ring 204 and the lower end ring 206 may be configured to support the swellable material 202 (e.g., limit axial movement of the swellable material 202 relative to the body portion 200) when the displacement sleeve tie-back sealing system 120 is lowered into the well and fixed in a set position. As described above, the swellable material 202 may be configured to expand in response to exposure to wellbore fluid. The upper end ring 204 and the lower end ring 206 may limit the expansion of the swellable material 202 in the axial direction so that the swellable material 202 may further expand in the radial direction. However, the displaced sleeve tieback sealing system 120 may also include a sleeve 208 configured to isolate the swellable material 202 from the wellbore fluid in the run-in position to prevent the swellable material 202 from prematurely expanding in the wellbore 104. As described in more detail below, the sleeve 208 may be displaced in a set position so that the swellable material 202 may expand to seal the displaced sleeve tieback sealing system 120 against the corresponding liner hanger 112, the liner 108, and / or the casing 102 disposed adjacent to the liner hanger 112.

[0011] In addition, as shown, the body portion 200 can include the lower end 122 of the liner tieback 116. That is, the lower end of the liner tieback 116 can be the body portion 200 of the shift sleeve tieback sealing system 120 so that the swellable material 202 can be disposed around the lower end of the liner tieback 116. Alternatively, the body portion 200 can be a separate body fixed to the lower end of the liner tieback 116. For example, the lower end of the liner tieback 116 and the shift sleeve tieback sealing system 120 can have corresponding threads so that the shift sleeve tieback sealing system 120 can be threadedly connected to the lower end of the liner tieback 116. In addition, the body portion 200 (e.g., a cylindrical body) is hollow so that production fluids (e.g., hydrocarbons) can flow through the central tool hole 210 of the body portion 200 and the central tieback hole 212 of the liner tieback 116 to the surface 118 ( Figure 1 shown).

[0012] In addition, as described above, the swellable material 202 may be configured to expand in response to exposure to a wellbore fluid. Specifically, the swellable material 202 may be configured to expand in response to a chemical reaction between the swellable material 202 and the fluid in the wellbore 104. That is, the swellable material 202 may include a specific metal alloy material configured to undergo a chemical reaction in response to exposure to the downhole fluid. The chemical reaction may cause the metal alloy material to transform into a rock-like material. When the metal alloy material transforms into the rock-like material, the swellable material 202 may expand. At least in part due to the upper end ring 204 and the lower end ring 206 limiting the axial expansion of the swellable material 202, the swellable material 202 may expand in a radially outward direction. The swellable material 202 may include any suitable alloy configured to expand in response to exposure to a downhole fluid. Alternatively, the swellable material 202 may be configured to expand in response to absorbing a fluid (e.g., water, hydrocarbons, etc.) from the wellbore 104. For example, the swellable material 202 may include a swellable elastomeric seal configured to absorb downhole fluid. When the swellable elastomeric seal absorbs the downhole fluid, the volume of the swellable elastomeric seal may increase. The increase in volume may cause the swellable elastomeric seal to expand in the radially outward direction 214.

[0013] As described above, the displaced sleeve tieback seal system 120 may further include a sleeve 208 configured to surround the swellable material 202 in the run-in position to prevent the swellable material 202 from prematurely expanding in the wellbore 104. As shown, in the run-in position, the lower end 216 of the sleeve 208 is secured to the lower end ring 206, and the upper end 218 of the sleeve 208 is secured to the upper end ring 204 to seal the swellable material 202 from the wellbore 104. Specifically, the sleeve 208 may be secured to the lower end ring 206 and the upper end ring 204 via at least one fastener 220. Alternatively, the sleeve 208 may be secured to only the lower end ring 206 or the upper end ring 204 via at least one fastener 220. That is, the sleeve 208 may be secured to the displaced sleeve tieback seal system 120 via at least one fastener 220 at only one location. However, the sleeve 208 may alternatively be secured via at least one fastener 220 at a plurality of locations along the length of the sleeve 208 , and may be secured to any suitable portion of the displacement sleeve tieback seal system 120 .

[0014] In addition, at least one fastener 220 can limit axial and / or radial movement of the sleeve 208 relative to the lower end ring 206 and the upper end ring 204 so that the seal between the sleeve 208 and the end rings (e.g., the upper end ring 204 and the lower end ring 206) can be maintained when the displacement sleeve tie-back seal system 120 is lowered into the well. The at least one fastener 220 can include at least one shear pin. For example, at least one upper shear pin 222 can secure the sleeve 208 to the upper end ring 204 and / or at least one lower shear pin 224 can secure the sleeve 208 to the lower end ring 206. However, any suitable fastener can be used to temporarily limit the axial and / or radial movement of the sleeve 208 relative to the end rings 204, 206 when the displacement sleeve tie-back seal system 120 is lowered into the well.

[0015] In addition, as described above, the lower end ring 206 can be disposed around the body portion 200 in a position below the swellable material 202, and the upper end ring 204 can be disposed around the body portion 200 in a position above the swellable material 202. As shown, the radially inner surfaces of each of the lower end ring 206 and the upper end ring 204 can be sealed to the body portion 200. In addition, the sleeve 208 (e.g., a metal sleeve) can have a tubular shape, which can be disposed around the end rings 204, 206 and the body portion 200 to enclose the swellable material 202. As such, the sleeve 208 can extend axially from the lower end ring 206 to the upper end ring 204 around at least the circumference of the body portion 200. In practice, the inner surface 226 of the sleeve 208 at the lower end 216 of the sleeve 208 is configured to engage (e.g., seal) with the radially outer surface 228 of the lower end ring 206, and the inner surface 226 of the sleeve 208 at the upper end 218 of the sleeve 208 is configured to engage (e.g., seal) with the radially outer surface 230 of the upper end ring 204 so that the sleeve 208 can seal the swellable material 202 from the wellbore 104 in the lowered position.

[0016] Figure 2B The displaced sleeve tieback sealing system 120 in a set position is disclosed. As described above, the displaced sleeve tieback sealing system 120 can be lowered into the well during completion operations to form a seal (e.g., a tieback seal) with the downhole tubulars 232 (e.g., liner hanger 112, liner 108, casing 102, etc.) so that the produced fluid can flow from the liner 108 to the liner tieback 116 and to the bottom surface 118 (e.g., Figure 1 As shown, in the set position, the swellable material 202 can expand to contact the liner hanger 112 and form a seal against the liner hanger. However, the swellable material 202 can alternatively or additionally expand at the set position to contact the liner 108 and / or the casing 102 and form a seal against the liner and / or the casing.

[0017] In addition, to form a tieback seal, the sleeve 208 of the shift sleeve tieback seal system 120 can be shifted in the set position so that the swellable material 202 can expand. As shown, the sleeve 208 can have a diameter similar to the top of the liner hanger 112 (e.g., the polished hole receiver) so that when the shift sleeve tieback seal system 120 is lowered into the well, the sleeve 208 can be radially aligned with the liner hanger 112. Therefore, when the tool (e.g., the shift sleeve tieback seal system 120) is moved axially downhole toward the set position (as shown), the sleeve 208 first contacts the top surface 234 of the liner hanger 112 in the set position. Such contact with the liner hanger 112 may move / displace the sleeve 208 to expose the swellable material 202 to the wellbore fluid so that the swellable material 202 may expand and seal against the downhole tubular 232 (eg, liner hanger 112 , liner 108 , and / or casing 102 ).

[0018] Specifically, contact between the sleeve 208 and the top surface 234 of the liner hanger 112 may prevent further movement of the sleeve 208 in an axial downhole direction 236 relative to the liner hanger 112. However, the weight on the displaced sleeve tieback seal system 120 (at least in part from the weight of the liner tieback 116) may drive the body portion 200, swellable material 202, lower end ring 206, and upper end ring 204 of the displaced sleeve tieback seal system 120 in an axial downhole direction 236 relative to the liner hanger 112. Thus, the weight on the tool may shear at least one fastener 220 (e.g., a shear pin) securing the sleeve 208 to the end rings 204, 206 such that the sleeve 208 is separated from the end rings 204, 206. When the sleeve 208 is separated, the body portion 200, the end rings 204, 206, and the swellable material 202 may move axially downhole relative to the sleeve 208 due to the weight on the tool. As shown, the body portion 200, the end rings 204, 206, and the swellable material 202 may be moved axially downhole into the central liner hanger bore 238 of the liner hanger 112. Additionally, the swellable material 202 may be exposed to the wellbore 104 (e.g., wellbore fluid) as the sleeve 208 is displaced. When the swellable material 202 reacts with the wellbore fluid, the swellable material 202 is configured to expand such that a radially outer surface 240 of the swellable material 202 contacts the liner hanger 112 and forms a seal against the liner hanger.

[0019] FIG. 3A to FIG. 3B A cross-sectional view of a displacement sleeve tieback sealing system with a hydrostatic assist chamber according to some embodiments of the present disclosure is shown. Specifically, Figure 3AA displaced sleeve tieback seal system 120 is shown having a hydrostatic assist chamber 300 ("chamber") disposed in a run-in position. The chamber 300 is configured to provide a biasing force to assist in fully stroking the sleeve 208 from the run-in position to the stroked position. Specifically, the chamber 300 is configured to assist in fully stroking the sleeve 208 such that the lower end 216 of the sleeve 208 is displaced from a position radially outward and axially aligned with the swellable material 202 (e.g., the run-in position) to a position axially uphole from the upper end 302 of the swellable material 202 (e.g., the stroked position). In some embodiments, the swellable material 202 may have a greater axial length than the polished bore receiver 304 of the liner hanger 112. Thus, the displaced sleeve tieback seal system 120 may bottom out at the downhole end 306 of the polished bore receiver 304 before the sleeve 208 is fully stroked. The hydrostatic assist chamber 300 may be configured to drive the sleeve 208 to a fully stroked position in an axial uphole direction 308 relative to the body portion 200 in response to shearing of the at least one fastener 220 (e.g., the at least one lower shear pin 224). Further, after the at least one fastener 220 is sheared, the hydrostatic assist chamber 300 may be configured to fully stroke the sleeve 208 without additional forces generated by contact between the sleeve 208 and the liner hanger 112 and / or another suitable downhole feature.

[0020] The hydrostatic assist chamber 300 may be configured to contain a compressible fluid (e.g., air) at atmospheric pressure. As shown, the chamber 300 may be disposed axially above the swellable material 202 and radially between the sleeve 208 and the body portion 200. For example, the chamber 300 may be defined by the radial inner surface 226 of the sleeve 208, the radial outer surface 310 of the body portion 200, the downhole surface 312 of the upper chamber ring 314, and the uphole surface 316 of the sleeve wall 318. The upper chamber ring 314 is disposed around the body portion 200 in a position axially uphole from the upper end ring 204. The upper chamber ring 314 may be rigidly fixed to the body portion 200 so that the upper chamber ring 314 maintains a fixed distance from the upper end ring 204 during operation. For reasons explained in more detail below, the stroke length of the sleeve 208 from the run-in position to the stroke position may be based at least in part on the distance between the upper end ring 204 and the upper chamber ring 314. In addition, the radially inner surface 320 of the upper chamber ring 314 can be fixed against the radially outer surface 310 of the main body portion 200 so that the upper chamber ring 314 is sealed against the main body portion 200 to prevent the compressible fluid from flowing out of the chamber 300. In addition, the radially outer surface 322 of the upper chamber ring 314 can be sealed against the radially inner surface 226 of the sleeve 208 to prevent the compressible fluid from flowing out of the chamber 300. Specifically, the shift sleeve tieback sealing system 120 may include at least one upper chamber ring seal 324 fixed to the radially outer surface 322 of the upper chamber ring 314. As described in more detail below, the sleeve 208 can be configured to move axially relative to the upper chamber ring 314. The at least one upper chamber ring seal 324 can be configured to contact the radially inner surface 226 of the sleeve 208 to maintain a seal between the upper chamber ring 314 and the sleeve 208 when the sleeve 208 moves relative to the upper chamber ring 314.

[0021] In addition, the sleeve 208 may include a sleeve wall 318 that projects radially inward from the radial inner surface 226 of the sleeve 208 around the circumference of the sleeve 208. That is, the sleeve wall 318 may extend radially inward from the radial inner surface 226 of the sleeve 208 to form a ring around the radial inner sleeve surface 226. The sleeve wall 318 may be disposed adjacent to the uphole end 326 of the upper end ring 204 in the run-in position. However, as described in more detail below, the sleeve wall 318 may be configured to move in the axial uphole direction 308 to a stroked position (e.g., a position adjacent to the downhole surface 312 of the upper chamber ring 314) during operation of the tool. In addition, the sleeve wall 318 may extend radially inward so that the sleeve wall 318 may seal against the body portion 200. Specifically, the radially inner surface 330 of the sleeve wall 318 may be configured to seal against the radially outer surface 310 of the body portion 200 via at least one sleeve wall seal 332 secured to the radially inner surface 330 of the sleeve wall 318. The sleeve wall seal 332 is configured to contact the radially outer surface 310 of the body portion 200 to maintain a seal between the sleeve wall 318 and the body portion 200 as the sleeve wall 318 moves along the body portion 200.

[0022] Thus, chamber 300 may be completely sealed to prevent compressible fluid from exiting chamber 300 via the seal formed between upper chamber ring 314 and body portion 200, the seal formed between upper chamber ring 314 and sleeve 208, and the seal between sleeve wall 318 and body portion 200. In effect, hydrostatic assist chamber 300 may be sealed such that it maintains atmospheric pressure within chamber 300.

[0023] Due to the pressure differential between the wellbore 104 and the hydrostatic assist chamber 300 (e.g., the wellbore pressure is greater than the pressure in the hydrostatic assist chamber 300), the force on the hydrostatic assist chamber 300 may bias the sleeve 208 to move in the axial uphole direction 308 relative to the main body portion 200. Specifically, the sleeve wall 318 of the sleeve 208 may be biased to move in the axial uphole direction 308 toward the upper chamber ring 314 to reduce the volume of the hydrostatic assist chamber 300; thereby, reducing the pressure differential. As described above, the biasing force is configured to help fully stroke the sleeve 208 from the run-in position to the stroked position. However, in the run-in position, the at least one fastener 220 may limit the axial movement of the sleeve 208 and the sleeve wall 318 relative to the main body portion 200. When the displacement sleeve tieback seal system 120 is run into the well, the biasing force from the pressure differential may be insufficient to shear the at least one fastener 220.

[0024] Figure 3B The displaced sleeve tieback seal system 120 is shown in a set position and the hydrostatic assist chamber 300 is disposed in a stroked position (e.g., a position in which the sleeve 208 is axially displaced such that the sleeve 208 is completely axially offset from the swellable material 202). In practice, the sleeve 208 may be positioned axially uphole from the upper end 302 of the swellable material 202 in the stroked position such that expansion of the swellable material 202 is not restricted by the sleeve 208. As described above, the swellable material 202 is configured to expand in response to exposure to wellbore fluids. In the run-in position, the sleeve 208 prevents the wellbore fluid from contacting the swellable material 202 such that the swellable material 202 does not expand prematurely. However, in the stroked position, the swellable material 202 is exposed to the wellbore 104 such that the swellable material 202 may react and expand to form a seal (e.g., a tieback seal) at the liner hanger 112, the liner 108, and / or the casing 102. As shown, the swellable material 202 is expanded to form a seal against the liner hanger 112. Furthermore, with the swellable material 202 sealing against the liner hanger 112, production fluids may be directed to flow from the liner 108 to the liner tieback 116 via the shift sleeve tieback sealing system 120.

[0025] The sleeve 208 may be displaced from the run-in position to the stroked position in response to the shift sleeve tie-back seal system 120 engaging a downhole feature having a suitable geometry (e.g., liner hanger 112, liner 108, etc.) in the set position. As described above, the at least one fastener 220 may limit axial movement of the sleeve 208 and the sleeve wall 318 relative to the body portion 200 in the run-in position. In addition, when the shift sleeve tie-back seal system 120 is run into the well, the biasing force generated by the pressure differential between the hydrostatic assist chamber 300 and the wellbore 104 may be insufficient to shear the at least one fastener 220 (e.g., the lower shear pin 224). However, in the set position, the engagement between the sleeve 208 and the downhole feature (e.g., liner hanger 112) may be configured to shear the at least one fastener 220 so that the sleeve 208 may be displaced from the run-in position to the stroked position. Specifically, when the tool (e.g., the shift sleeve tieback seal system 120) is moved axially downhole toward the set position (as shown), the sleeve 208 first contacts the top surface 234 of the liner hanger 112 in the set position. Such contact with the liner hanger 112 may apply sufficient force to the sleeve 208 to shear the at least one fastener 220 so that the hydrostatic assist chamber 300 may drive the sleeve 208 from the run-in position to the stroked position.

[0026] Specifically, contact between the sleeve 208 and the top surface 234 of the liner hanger 112 may prevent further movement of the sleeve 208 in an axial downhole direction 236 relative to the liner hanger 112. However, the weight on the displaced sleeve tieback seal system 120 (at least in part from the weight of the liner tieback 116) may drive the body 200, swellable material 202, upper chamber ring 314, and end rings 204, 206 of the displaced sleeve tieback seal system 120 in a downhole direction relative to the liner hanger 112. Thus, the weight on the tool may shear the at least one fastener 220 securing the sleeve 208 to the lower end ring 206 and / or the upper end ring 204 such that the sleeve 208 is separated from the lower end ring 206 and / or the upper end ring 204. As the sleeve 208 is separated, the body portion 200, the end rings 204, 206, and the swellable material 202 may be moved axially downhole relative to the sleeve 208 into the center liner hanger bore 238 of the liner hanger 112. As the body portion 200 is moved axially downhole, continued contact between the sleeve 208 and the liner hanger 112 may drive the sleeve 208 from the run-in position to the stroked position. However, as described above, the hydrostatic assist chamber 300 may assist in driving the sleeve 208 axially upward to the fully stroked position. For example, as described above, the swellable material 202 may have a greater axial length than the polished bore receiver 304 of the liner hanger 112. Therefore, before the sleeve 208 is fully stroked, the displaced sleeve tieback seal system 120 may bottom out at the downhole end 306 of the liner hanger 112. However, the hydrostatic assist chamber 300 may continue to drive the sleeve 208 axially upward to the fully stroked position relative to the body portion 200. Alternatively, once the at least one fastener 220 is sheared, the hydrostatic assist chamber 300 may drive the sleeve 208 from the run-in position to the stroked position independently of the liner hanger 112 .

[0027] In addition, in the run-in position, the sleeve wall 318 of the sleeve 208 may be fixed in the run-in position (e.g., in a position adjacent to the uphole end 326 of the upper end ring 204). In response to shearing of the at least one fastener 220, the sleeve 208 may be released to slide axially relative to the body portion 200, the upper end ring 204, and the upper chamber ring 314. As the sleeve 208 is released, the biasing force from the pressure differential between the hydrostatic assist chamber 300 and the wellbore 104 may drive the sleeve wall 318 to move from the run-in position to the stroked position. As shown, the sleeve wall 318 may be positioned adjacent to the downhole surface 312 of the upper chamber ring 314 in the fully stroked position. The hydrostatic assist chamber 300 may drive the sleeve wall 318 to move toward the upper chamber ring 314 until the pressure in the chamber 300 is balanced with the wellbore pressure outside the chamber 300. However, due to the difference in pressure within chamber 300 in the run-in position compared to the wellbore pressure, the fully stroked position of sleeve 208 may position sleeve wall 318 adjacent upper chamber annulus 314 as shown.

[0028] Furthermore, the distance between the sleeve wall 318 and the upper chamber ring 314 in the run-in position may determine the stroke length of the sleeve 208. Thus, the distance between the sleeve wall 318 and the upper chamber ring 314 in the run-in position may be greater than the axial length of the swellable material 202 such that the sleeve 208 may be moved to a position that is fully axially offset from the swellable material 202. That is, the stroke length may be sufficient such that the sleeve 208 may be positioned axially uphole from the upper end 302 of the swellable material 202 in the stroked position such that expansion of the swellable material 202 is not restricted by the sleeve 208.

[0029] FIG. 4A to FIG. 4C A cross-sectional view of a displacement sleeve tieback sealing system sealing against a casing and liner hanger according to some embodiments of the present disclosure is shown. Specifically, Figure 4A A displacement sleeve tieback seal system 120 is shown with a hydrostatic assist chamber 300 disposed in a run-in position. As described above, the displacement sleeve tieback seal system 120 includes a body portion 200 and a swellable material 202 disposed about a circumference of the body portion 200. Specifically, the swellable material 202 may be disposed between an upper end ring 204 and a lower end ring 206, each of which is disposed about the body portion 200. The upper end ring 204 may be positioned uphole from the lower end ring 206. In addition, the body portion 200 may include a recessed portion 400 (e.g., a span of the body portion 200 having a reduced outer diameter). As shown, the upper end ring 204 and the lower end ring 206 may be secured about the recessed portion 400. The recessed portion 400 may help limit axial movement of the upper end ring 204 and the lower end ring 206. For example, an upper end 402 of the recessed portion 400 may contact the upper end ring 204 to limit axial uphole movement of the upper end ring 204 , and a lower end 404 of the recessed portion 400 may contact the lower end ring 206 to limit axial downhole movement of the lower end ring 206 .

[0030] In addition, the swellable material 202 may be disposed around the recessed portion 400 in a position between the upper end ring 204 and the lower end ring 206. The upper end ring 204 and the lower end ring 206 may be configured to support the swellable material 202 (e.g., limit axial movement of the swellable material 202 relative to the body portion 200) when the displacement sleeve tieback seal system 120 is lowered into the well and fixed in a set position. As described above, the swellable material 202 may be configured to expand in response to exposure to wellbore fluid. The upper end ring 204 and the lower end ring 206 may limit the expansion of the swellable material 202 in the axial direction so that the swellable material 202 can further expand in the radial direction. However, as described above, the displacement sleeve tieback seal system 120 may also include a sleeve 208 that is configured to isolate the swellable material 202 from the wellbore fluid in the lowered position to prevent the swellable material 202 from prematurely expanding in the wellbore 104.

[0031] The sleeve 208 may have a tubular shape disposed in a re-entered position around the swellable material 202. In addition, the sleeve 208 may be disposed around the lower end ring 206, the upper end ring 204, and the lower chamber ring 406. As shown, an upper portion 408 of the sleeve 208 may be fixed to the lower chamber ring 406. Specifically, a radially inner surface 410 of the upper portion 408 of the sleeve 208 may be fixed to a radially outer surface 412 of the lower chamber ring 406 via at least one set screw 414 or any other suitable fastener to rigidly fix the sleeve 208 to the lower chamber ring 406. In addition, a lower portion 416 of the sleeve 208 may be fixed to the lower end ring 206. Specifically, radially inner surface 418 of lower portion 416 of sleeve 208 may be secured to radially outer surface 228 of lower end ring 206 via at least one shearable member 420 (e.g., lower shear pin 224) to rigidly secure sleeve 208 to lower end ring 206 in the run-in position. Lower end ring 206 may also be rigidly secured to body portion 200 such that movement of sleeve 208 relative to body portion 200 is restricted in the run-in position. In addition, the upper portion 408 of the sleeve 208 can be sealed against the lower chamber ring 406 via the upper portion housing seal 422, the lower portion 416 of the sleeve 208 can be sealed against the lower end ring 206 via the outer lower housing seal 424, the lower chamber ring 406 can be sealed against the main body 200 via the lower chamber seal 426, and the lower end ring 206 can be sealed against the recessed portion 400 via the inner lower housing seal 428 so that the swellable material 202 can be isolated / sealed from the wellbore fluid in the lowered position.

[0032] However, as described in more detail below, the sleeve 208 may be displaced axially upward in the set position so that the swellable material 202 may be exposed to the wellbore fluid at a desired location in the wellbore 104. The lower end 216 of the sleeve 208 may be configured to engage a downhole feature having a suitable geometry (e.g., a liner hanger 112, a liner 108, etc.) in the set position. For example, the lower end 216 of the sleeve 208 may extend axially downhole from the lower end ring 206 in the run-in position so that the liner hanger 112 may engage the sleeve 208 before the lower end ring 206 lands on the liner hanger 112. Such engagement between the sleeve 208 and the liner hanger 112 may shear the at least one shearable member 420 (e.g., the lower shear pin 224) so ​​that the sleeve 208 may be displaced from the run-in position to the stroked position.

[0033] In addition, the hydrostatic assist chamber 300 is configured to provide a biasing force to assist in fully stroking the sleeve 208 from the run-in position to the stroked position. Alternatively or additionally, the displaced sleeve tieback seal system 120 may include a biasing mechanism (e.g., a spring, a mechanical actuator, etc.) to assist in fully stroking the sleeve 208. In addition, the hydrostatic assist chamber 300 is configured to assist in fully stroking the sleeve 208 such that the lower end 216 of the sleeve 208 is displaced from a position radially outward and axially aligned with the swellable material 202 (e.g., the run-in position) to a position axially uphole from the upper end 302 of the swellable material 202 (e.g., the stroked position). The hydrostatic assist chamber 300 may be configured to drive the sleeve 208 axially upward relative to the body portion 200 to the fully stroked position in response to shearing of the at least one shearable member 420 (e.g., the at least one lower shear pin 224). Furthermore, after the at least one shearable member 420 is sheared, the hydrostatic assist chamber 300 may be configured to fully stroke the sleeve 208 without additional forces generated by contact between the sleeve 208 and the liner hanger 112 .

[0034] The hydrostatic assist chamber 300 includes a chamber 300 for containing a compressible fluid (e.g., air) at atmospheric pressure. As shown, the chamber 300 may be disposed axially above the swellable material 202 and radially between the chamber sleeve 430 and the body portion 200. For example, the chamber 300 may be defined by a radially inner surface 432 of the chamber sleeve 430, a radially outer surface 310 of the body portion 200, a downhole surface 312 of an upper chamber ring 314, and an uphole surface 434 of a lower chamber ring 406. The upper chamber ring 314 may have a hollow cylindrical shape and may be disposed around the body portion 200 in a position axially uphole from the upper end ring 204. The upper chamber ring 314 may be rigidly fixed to the body portion 200 so that the upper chamber ring 314 maintains a fixed distance from the upper end ring 204 during operation. Furthermore, the radially inner surface 320 of the upper chamber ring 314 may be fixed against the radially outer surface 310 of the body portion 200 such that the upper chamber ring 314 is sealed against the body portion 200 to prevent the compressible fluid from flowing out of the chamber 300. Additionally, the radially outer surface 322 of the upper chamber ring 314 may be sealed against the radially inner surface 432 of the chamber sleeve 430 to prevent the compressible fluid from flowing out of the chamber 300. Specifically, at least one upper chamber ring seal 324 may be fixed to the radially outer surface 322 of the upper chamber ring 314, and at least one upper chamber ring seal 324 may be configured to contact the radially inner surface 432 of the chamber sleeve 430 to maintain a seal between the upper chamber ring 314 and the chamber sleeve 430 when the chamber sleeve 430 moves relative to the upper chamber ring 314.

[0035] The chamber sleeve 430 may be rigidly fixed to the lower chamber ring 406 and seal against the lower chamber ring. Specifically, at least the radially inner surface 432 of the chamber sleeve 430 may be rigidly fixed to the radially outer surface 412 of the lower chamber ring 406 and seal against the radially outer surface of the lower chamber ring to prevent the compressible fluid from flowing out of the chamber 300. In addition, the sleeve 208 may be rigidly fixed to the lower chamber ring 406. Therefore, the movement of the sleeve 208 via contact with the liner hanger 112 may drive the movement of the lower chamber ring 406 and the chamber sleeve 430. In addition, the lower chamber ring 406 may include a hollow cylindrical shape disposed around the body portion 200. In addition, the lower chamber ring 406 may be disposed adjacent to the upper end ring 204 in the down position. However, the lower chamber ring 406 may be configured to move in the axial uphole direction 308 to a stroke position (e.g., a position adjacent to the downhole surface 312 of the upper chamber ring 314) during operation of the tool. In addition, the lower chamber ring 406 may be sealed against the main body portion 200. That is, the radially inner surface 436 of the lower chamber ring 406 may be configured to seal against the radially outer surface 310 of the main body portion 200 via at least one lower chamber seal 426 fixed to the radially inner surface 436 of the lower chamber ring 406. The lower chamber seal 426 is configured to contact the radially outer surface 310 of the main body portion 200 to maintain a seal between the lower chamber ring 406 and the main body portion 200 to prevent the compressible fluid from flowing out of the chamber 300 when the lower chamber ring 406 moves along the main body portion 200.

[0036] Thus, chamber 300 may be completely sealed to prevent compressible fluid from exiting chamber 300 via the seal formed between upper chamber ring 314 and body portion 200, the seal formed between upper chamber ring 314 and chamber sleeve 430, the seal formed between chamber sleeve 430 and lower chamber ring 406, and the seal formed between lower chamber ring 406 and body portion 200. In effect, hydrostatic assist chamber 300 may be sealed such that it maintains atmospheric pressure within chamber 300.

[0037] Due to the pressure differential between the wellbore 104 and the hydrostatic assist chamber 300 (e.g., the wellbore pressure is greater than the pressure in the hydrostatic assist chamber 300), the force on the hydrostatic assist chamber 300 may bias the lower chamber ring 406 to move in the axial uphole direction 308 relative to the main body portion 200. Specifically, the lower chamber ring 406 may be biased to move in the axial uphole direction 308 toward the upper chamber ring 314 to reduce the volume of the hydrostatic assist chamber 300; thereby, reducing the pressure differential. Since the sleeve 208 is rigidly fixed to the lower chamber ring 406, the biasing force is configured to help the sleeve 208 fully stroke from the run-in position to the stroked position. However, in the run-in position, the at least one shearable member 420 may limit the axial movement of the sleeve 208 and the lower chamber ring 406 relative to the main body portion 200. When the displacement sleeve tieback seal system 120 is run into the well, the biasing force from the pressure differential may be insufficient to shear the at least one shearable member 420.

[0038] Figure 4B The shift sleeve tieback sealing system 120 in a set position and the hydrostatic assist chamber 300 disposed in a run-in position are shown. As shown, the shift sleeve tieback sealing system 120 may include a seal assembly 438 extending from a downhole end 440 of the body portion 200. The seal assembly 438 may have a tubular shape with a larger diameter than the body portion 200. Specifically, the diameter of the radially outer surface 442 of the seal assembly 438 may be substantially similar to the diameter of the radially inner surface 444 of the liner hanger 112 so that the seal assembly 438 can seal against the radially inner surface 444 of the liner hanger 112. In addition, the seal assembly 438 may include a plurality of seals 446 fixed to the radially outer surface 442 of the seal assembly 438. In practice, as shown, the seal assembly 438 may enter the central liner hanger bore 238 of the liner hanger 112 in the set position so that the plurality of seals 446 can seal the seal assembly 438 against the liner hanger 112. With the seal assembly 438 sealed against the liner hanger 112 , production fluids flowing upward from the liner 108 may flow into the liner tieback 116 without leaking into the wellbore 104 .

[0039] In addition, the sleeve 208 may be configured to engage the liner hanger 112 in the set position. In response to the shift sleeve tieback sealing system 120 engaging the liner hanger 112 in the set position, the sleeve 208 may be displaced from the run-in position to the stroked position. As described above, at least one shearable member 420 (e.g., lower shear pin 224) may limit axial movement of the sleeve 208 and the lower chamber ring 406 relative to the body portion 200 in the run-in position. In addition, when the shift sleeve tieback sealing system 120 is run into the well, the biasing force generated by the pressure differential between the hydrostatic assist chamber 300 and the wellbore 104 may be insufficient to shear the at least one shearable member 420. However, in the set position, the engagement between the sleeve 208 and the liner hanger 112 may be configured to shear the at least one shearable member 420 so that the sleeve 208 may be displaced from the run-in position to the stroked position. Specifically, when the tool (e.g., the shift sleeve tieback seal system 120) is moved axially downhole toward the set position, the lower end 216 of the sleeve 208 first contacts the top surface 234 of the liner hanger 112 in the set position. Such contact with the liner hanger 112 can apply sufficient force to the sleeve 208 to shear the at least one shearable member 420. With the at least one shearable member 420 sheared, the biasing force from the hydrostatic assist chamber can drive the sleeve 208 from the run-in position to the stroked position.

[0040] Specifically, contact between the sleeve 208 and the top of the liner hanger 112 may prevent further movement of the sleeve 208 in the axial downhole direction 236 relative to the liner hanger 112. However, the weight on the displaced sleeve tieback seal system 120 (at least in part from the weight of the liner tieback 116) may drive the body 200, swellable material 202, lower end ring 206, upper end ring 204, and upper chamber ring 314 of the displaced sleeve tieback seal system 120 in the axial downhole direction 236 relative to the liner hanger 112. Thus, the weight on the tool may shear the at least one shearable member 420 securing the sleeve 208 to the lower end ring 206 such that the sleeve 208 is separated from the lower end ring 206.

[0041] Figure 4C The displaced sleeve tieback seal system 120 is shown in a set position and the hydrostatic assist chamber 300 is disposed in a stroked position (e.g., a position in which the sleeve is axially displaced such that the sleeve 208 is fully axially offset from the swellable material 202). In practice, the sleeve 208 may be positioned axially uphole from the upper end 302 of the swellable material 202 in the stroked position such that expansion of the swellable material 202 is not restricted by the sleeve 208. As described above, the swellable material 202 is configured to expand in response to exposure to wellbore fluids. In the run-in position, the sleeve 208 prevents the wellbore fluid from contacting the swellable material 202 such that the swellable material 202 does not expand prematurely. However, in the stroked position, the swellable material 202 is exposed to the wellbore 104 such that the swellable material 202 may react and expand to form a seal (e.g., a tieback seal) against the liner hanger 112, the liner 108, and / or the casing 102. As shown, the swellable material 202 is expanded to form a seal against the casing 102. In addition, with the swellable material 202 sealed against the casing 102 and the seal assembly 438 sealed against the liner hanger 112, production fluids can be directed to flow from the liner 108 to the liner tieback 116 via the shift sleeve tieback sealing system 120.

[0042] In addition, as described above, at least one shearable member 420 (e.g., lower shear pin 224) securing sleeve 208 to lower end ring 206 may be sheared at a set position such that sleeve 208 is separated from ring 206 from the lower end. As sleeve 208 is separated, body portion 200, upper chamber ring 314, lower end ring 206, upper end ring 204, and swellable material 202 may be axially moved relative to sleeve 208 into central liner hanger bore 238 of liner hanger 112 until lower end ring 206 lands on top surface 234 of liner hanger 112. Alternatively, engagement of seal assembly 438 with radial inner surface 444 of liner hanger 112 and / or expansion of swellable material 202 may set the displaced sleeve tieback seal system 120 before lower end ring 206 lands on liner hanger 112. Furthermore, once at least one shearable member 420 is sheared and sleeve 208 is released, the hydrostatic assist chamber 300 can drive sleeve 208 axially upward to the fully stroked position. In fact, the hydrostatic assist chamber 300 can drive sleeve 208 from the run-in position to the stroked position independently of other biasing forces.

[0043] In the run-in position, the lower chamber ring 406 of the sleeve 208 may be fixed in a position adjacent to the uphole end 326 of the upper end ring 204. In response to the shearing of the at least one shearable member 420, the sleeve 208 may be released to slide axially relative to the upper chamber ring 314. Since the lower chamber ring 406 is rigidly fixed to the sleeve 208, in response to the at least one shearable member 420 being sheared, the lower chamber ring 406 may also be released to slide axially relative to the upper chamber ring 314. As the lower chamber ring 406 is released, the biasing force from the pressure differential between the hydrostatic assist chamber 300 and the wellbore 104 may drive the lower chamber ring 406 to move from the run-in position to the stroked position. As shown, the lower chamber ring 406 may be positioned adjacent to the downhole surface 312 of the upper chamber ring 314 in the fully stroked position. The hydrostatic assist chamber 300 may drive the lower chamber ring 406 to move toward the upper chamber ring 314 until the pressure in the chamber 300 is balanced with the wellbore pressure outside the chamber 300. However, due to the difference in pressure within chamber 300 in the run-in position compared to the wellbore pressure, the fully stroked position of lower chamber ring 406 may position lower chamber ring 406 adjacent upper chamber ring 314 as shown.

[0044] Furthermore, the distance between the lower chamber ring 406 and the upper chamber ring 314 in the run-in position may determine the stroke length of the sleeve 208. Thus, the distance between the lower chamber ring 406 and the upper chamber ring 314 in the run-in position may be greater than the axial length of the swellable material 202 such that the sleeve 208 may be moved to a position that is fully axially offset from the swellable material 202. That is, the stroke length may be sufficient such that the sleeve 208 may be positioned axially uphole from the upper end 302 of the swellable material 202 in the stroked position such that expansion of the swellable material 202 is not restricted by the sleeve 208.

[0045] Thus, the present disclosure may provide a displaced sleeve tieback seal system configured to form a seal with a corresponding liner by axially displacing a sleeve in response to contact with a liner hanger such that a swellable material may expand to form a seal.

[0046] Statement 1. A displaced sleeve tieback sealing system comprising: a main body portion; a swellable material disposed around a circumference of the main body portion, wherein the swellable material is configured to expand in response to exposure to a wellbore fluid; an upper end ring disposed around the main body portion in a position axially above the swellable material; a lower end ring disposed around the main body portion in a position axially below the swellable material; and a sleeve disposed radially outwardly from the swellable material in a run-in position and sealing against the upper end ring and / or the lower end ring to isolate the swellable material from the wellbore fluid, wherein the sleeve is configured to contact a downhole feature in a set position, and wherein contact with the downhole feature is configured to move the sleeve to expose the swellable material to the wellbore fluid such that the swellable material expands to seal against a downhole tubular.

[0047] Statement 2. The displaced sleeve tieback seal system of Statement 1 wherein said downhole feature comprises a liner hanger.

[0048] Statement 3. The displaced sleeve tieback seal system of Statement 1 or Statement 2, wherein the swellable material is configured to chemically react with the wellbore fluid, and wherein the chemical reaction causes the swellable material to expand.

[0049] Statement 4. The displaced sleeve tieback seal system of Statement 1 or Statement 2, wherein the swellable material is configured to absorb a portion of the wellbore fluid, and wherein absorbing the portion of the wellbore fluid is configured to cause the swellable material to expand.

[0050] Statement 5. A displaced sleeve tieback seal system according to any preceding statement, further comprising at least one seal disposed between said sleeve and said upper end ring and / or said lower end ring in said run-in position.

[0051] Statement 6. The displaced sleeve tieback seal system of any preceding statement wherein the distal end of the sleeve is configured to extend downhole from the lower end ring shaft in the run-in position.

[0052] Statement 7. A displacement sleeve tieback seal system according to any preceding statement wherein said sleeve is secured to said upper end ring and / or said lower end ring in said run-in position via at least one fastener.

[0053] Statement 8. The shift sleeve tieback seal system of any preceding statement wherein said at least one fastener comprises at least one shear pin.

[0054] Statement 9. A shift sleeve tie-back sealing system according to any of the preceding statements, wherein contact between the distal end of the sleeve and the downhole feature in the set position is configured to shear the at least one fastener to release the sleeve to move relative to the upper end ring and / or the lower end ring in response to movement of the main body portion relative to the downhole feature.

[0055] Statement 10. The displaced sleeve tieback seal system of any preceding statement, further comprising a hydrostatic assist chamber configured to drive the sleeve axially upwardly to a set position relative to the body portion and / or the downhole feature.

[0056] Statement 11. A displaced sleeve tieback seal system according to any preceding statement wherein the hydrostatic assist chamber is formed between a radially outer surface of the body portion, a radially inner surface of the chamber sleeve, an upper chamber ring and a lower chamber ring.

[0057] Statement 12. The shift sleeve tieback seal system of any preceding statement wherein said chamber sleeve is rigidly secured to said lower chamber ring, and wherein said chamber sleeve and said lower chamber ring are configured to move axially relative to said upper chamber ring.

[0058] Statement 13. A displaced sleeve tieback sealing system according to any preceding statement, wherein the hydrostatic assist chamber is configured to contain a compressible fluid at atmospheric pressure in the run-in position, wherein a pressure differential between the hydrostatic assist chamber and the wellbore is configured to bias the lower chamber ring axially toward the upper chamber ring.

[0059] Statement 14. A shift sleeve tie-back sealing system according to any of the preceding statements, wherein the upper portion of the sleeve is fixed to the lower chamber ring, wherein the lower portion of the sleeve is fixed to the lower end ring via fasteners in the lowered position, and wherein the lower end ring is rigidly fixed to the main body portion so that movement of the lower chamber ring toward the upper chamber ring is restricted in the lowered position.

[0060] Statement 15. The displaced sleeve tieback seal system of any preceding statement, further comprising a biasing mechanism configured to drive said sleeve axially upwardly to a set position relative to said body portion and / or said downhole feature.

[0061] Statement 16. The displaced sleeve tieback sealing system of any preceding statement, wherein said swellable material expands to seal against said downhole tubular, and wherein said downhole tubular comprises a liner, a liner hanger, a polished bore receiver, a casing, or some combination thereof.

[0062] Statement 17. A displaced sleeve tieback sealing system comprising: a main body portion; a swellable material disposed around the circumference of the main body portion, wherein the swellable material is configured to expand in response to exposure to a wellbore fluid; an upper end ring disposed around the main body portion in a position axially above the swellable material; a lower end ring disposed around the main body portion in a position axially below the swellable material; wherein the upper end ring and the lower end ring are configured to limit axial expansion of the swellable material; a lower chamber ring disposed around the main body portion in a position axially above the lower end ring; an upper chamber ring disposed around the main body portion in a position axially above the lower chamber ring; a sleeve secured in a run-in position and sealed against the lower end ring and the lower chamber ring to isolate the swellable material from the wellbore fluid, wherein the the sleeve being secured to the lower end ring via at least one shearable member, wherein the sleeve is configured to contact a liner hanger in a set position, and wherein contact with the liner hanger is configured to shear the at least one shearable member to release the sleeve and lower chamber ring to move the swellable material and expose it to a wellbore fluid; a hydrostatic assist chamber formed between a radially outer surface of the body portion, a radially inner surface of the chamber sleeve, the lower chamber ring, and the upper chamber ring, wherein the hydrostatic assist chamber is configured to contain a compressible fluid at atmospheric pressure in the run-in position, and wherein a pressure differential between the hydrostatic assist chamber and the wellbore is configured to drive the lower chamber ring axially toward the upper chamber ring and move the sleeve axially upward relative to the body portion and the liner hanger to a set position, wherein the set position is axially offset from the swellable material.

[0063] Statement 18. The displaced sleeve tieback seal system of Statement 17, wherein said swellable material is configured to chemically react with said wellbore fluid, and wherein said chemical reaction causes said swellable material to expand.

[0064] Statement 19. The displaced sleeve tieback seal system of Statement 17 or Statement 18, wherein the swellable material is configured to absorb a portion of the wellbore fluid, and wherein absorbing the portion of the wellbore fluid is configured to expand the swellable material.

[0065] Statement 20. A method comprising: extending a displaced sleeve tie-back sealing system into a wellbore toward a liner hanger, wherein the displaced sleeve tie-back sealing system includes a main body portion, a swellable material disposed around a circumference of the main body portion and configured to swell in response to exposure to a wellbore fluid, and a sleeve configured to isolate the swellable material from the wellbore fluid in a run-in position; driving the sleeve into the liner hanger to shear at least one fastener holding the sleeve in the run-in position; in response to the at least one fastener being sheared, moving the sleeve relative to the main body portion from the run-in position to a set position via the hydrostatic assist chamber; and in response to movement of the sleeve exposing the swellable material to the wellbore fluid, causing the swellable material to swell to seal against a downhole tubular.

[0066] Therefore, the present embodiment is well adapted to achieve the objects and advantages mentioned as well as those inherent therein. The particular embodiments disclosed above are illustrative only, as the present embodiments may be modified and practiced in different but equivalent ways apparent to those skilled in the art who benefit from the teachings herein. Although individual embodiments are discussed, all combinations of each embodiment are contemplated and encompassed by the present disclosure. Furthermore, it is not intended to limit the details of construction or design shown herein, except as described in the claims below. In addition, the terms in the claims have their ordinary general meaning unless otherwise clearly and distinctly defined by the patentee. Therefore, it is apparent that the particular illustrative embodiments disclosed above may be changed or modified, and all such variations are deemed to be within the scope and spirit of the present disclosure.

Claims

1. A displacement sleeve tie-back sealing system, comprising: The main part; a swellable material disposed about a circumference of the body portion, wherein the swellable material is configured to expand in response to exposure to a wellbore fluid; an upper end ring disposed around the body portion in a position axially above the swellable material; a lower end ring disposed about the body portion in a position axially below the swellable material; and a sleeve disposed radially outwardly from the swellable material in a run-in position and sealing against the upper end ring and / or the lower end ring to isolate the swellable material from a wellbore fluid, wherein the sleeve is configured to contact a downhole feature in a set position, and wherein contact with the downhole feature is configured to move the sleeve to expose the swellable material to the wellbore fluid such that the swellable material expands to seal against a downhole tubular.

2. The displaced sleeve tieback sealing system of claim 1, wherein the downhole feature comprises a liner hanger.

3. The displaced sleeve tieback sealing system of claim 1, wherein the swellable material is configured to chemically react with the wellbore fluid, and wherein the chemical reaction causes the swellable material to expand.

4. The displaced sleeve tieback sealing system of claim 1, wherein the swellable material is configured to absorb a portion of the wellbore fluid, and wherein absorbing the portion of the wellbore fluid is configured to expand the swellable material.

5. The displacement sleeve tieback sealing system of claim 1, further comprising at least one seal disposed between the sleeve and the upper end ring and / or the lower end ring in the run-in position.

6. The displaced sleeve tieback sealing system of claim 5, wherein the distal end of the sleeve is configured to extend axially downhole from the lower end ring in the run-in position.

7. The displacement sleeve tieback sealing system of claim 1, wherein the sleeve is secured to the upper end ring and / or the lower end ring in the run-in position via at least one fastener.

8. The displacement sleeve tieback sealing system of claim 7, wherein the at least one fastener comprises at least one shear pin.

9. A shift sleeve tie-back sealing system according to claim 7, wherein the contact between the distal end of the sleeve and the downhole feature in the set position is configured to shear the at least one fastener to release the sleeve to move relative to the upper end ring and / or the lower end ring in response to movement of the main body portion relative to the downhole feature.

10. The displaced sleeve tieback sealing system of claim 1, further comprising a hydrostatic assist chamber configured to axially drive the sleeve upward to a set position relative to the body portion and / or the downhole feature.

11. The displaced sleeve tie-back sealing system according to claim 10, wherein the hydrostatic auxiliary chamber is formed between the radial outer surface of the main body portion, the radial inner surface of the chamber sleeve, the upper chamber ring and the lower chamber ring.

12. The shift sleeve tieback seal system of claim 11, wherein the chamber sleeve is rigidly secured to the lower chamber ring, and wherein the chamber sleeve and the lower chamber ring are configured to move axially relative to the upper chamber ring.

13. The displaced sleeve tieback sealing system of claim 11, wherein the hydrostatic assist chamber is configured to contain a compressible fluid at atmospheric pressure in the run-in position, wherein a pressure differential between the hydrostatic assist chamber and the wellbore is configured to bias the lower chamber ring axially toward the upper chamber ring.

14. A shift sleeve tie-back sealing system according to claim 13, wherein the upper portion of the sleeve is fixed to the lower chamber ring, wherein the lower portion of the sleeve is fixed to the lower end ring via fasteners in the lowered position, and wherein the lower end ring is rigidly fixed to the main body portion so that movement of the lower chamber ring toward the upper chamber ring is restricted in the lowered position.

15. The displaced sleeve tieback seal system of claim 1, further comprising a biasing mechanism configured to drive the sleeve axially upward to a set position relative to the body portion and / or the downhole feature.

16. The displaced sleeve tieback sealing system of claim 1, wherein the swellable material expands to seal against the downhole tubular, and wherein the downhole tubular comprises a liner, a liner hanger, a polished bore receiver, a casing, or some combination thereof.

17. A displacement sleeve tie-back sealing system, comprising: The main part; a swellable material disposed about a circumference of the body portion, wherein the swellable material is configured to expand in response to exposure to a wellbore fluid; an upper end ring disposed around the body portion in a position axially above the swellable material; a lower end ring disposed around the body portion in a position axially below the swellable material; wherein the upper end ring and the lower end ring are configured to limit axial expansion of the swellable material; a lower chamber ring, the lower chamber ring being arranged around the main body portion in a position axially above the lower end ring; an upper chamber ring, the upper chamber ring being arranged around the main body portion in a position axially above the lower chamber ring; a sleeve secured in a run-in position and sealing against the lower end ring and the lower chamber ring to isolate the swellable material from wellbore fluids, wherein the sleeve is secured to the lower end ring via at least one shearable member, wherein the sleeve is configured to contact a liner hanger in a set position, and wherein contact with the liner hanger is configured to shear the at least one shearable member to release the sleeve and lower chamber ring to dislodge the swellable material and expose it to wellbore fluids; a hydrostatic assist chamber formed between a radially outer surface of the body portion, a radially inner surface of a chamber sleeve, the lower chamber ring, and the upper chamber ring, wherein the hydrostatic assist chamber is configured to contain a compressible fluid at atmospheric pressure in the run-in position, and wherein a pressure differential between the hydrostatic assist chamber and the wellbore is configured to drive the lower chamber ring axially toward the upper chamber ring and move the sleeve axially upward relative to the body portion and the liner hanger to a set position, wherein the set position is axially offset from the swellable material.

18. The displaced sleeve tieback sealing system of claim 17, wherein the swellable material is configured to chemically react with the wellbore fluid, and wherein the chemical reaction causes the swellable material to expand.

19. The displaced sleeve tieback sealing system of claim 17, wherein the swellable material is configured to absorb a portion of the wellbore fluid, and wherein absorbing the portion of the wellbore fluid is configured to expand the swellable material.

20. A method comprising: extending a displaced sleeve tieback seal system into the wellbore toward the liner hanger, wherein the displaced sleeve tieback seal system includes a body portion, a swellable material disposed about a circumference of the body portion and configured to swell in response to exposure to a wellbore fluid, and a sleeve configured to isolate the swellable material from the wellbore fluid in a run-in position; driving the sleeve into the liner hanger to shear at least one fastener holding the sleeve in the run-in position; in response to the at least one fastener being sheared, moving the sleeve relative to the body portion via the hydrostatic assist chamber from the run-in position to a set position; and In response to movement of the sleeve exposing the swellable material to wellbore fluid, the swellable material is expanded to seal against a downhole tubular.

Images