System and method for deploying a casing patch

Disclosed are systems and methods for deploying a casing patch in a wellbore. One casing patch assembly includes a setting kit arranged at an uphole end, an upper wedge portion operatively coupled to the setting kit and defining an upper ramp portion, a lower wedge portion arranged at a downhole end and defining a lower ramp portion, and a casing patch axially interposing the upper and lower wedge portions and having a proximal end configured to radially expand upon slidably engaging the upper ramp portion and a distal end configured to radially expand upon slidably engaging the lower ramp portion.

This application is a National Stage entry of and claims priority to International Application No. PCT/US2013/041328, filed on May 16, 2013.

BACKGROUND

The present disclosure is related to downhole tools and, more particularly, to a system and method for deploying a casing patch.

Wellbores drilled in the oil and gas industry are typically completed by cementing tubular casing strings within the newly formed borehole. The casing is commonly perforated or otherwise penetrated in order to evaluate and stimulate the surrounding subterranean formations. Besides these intentional perforations made in the casing, several unintentional holes or defects are also often created in the casing as a result of various wellbore intervention operations, remedial wellbore work and maintenance, or general weakness in the casing material. Such holes or defects can result in the development of unwanted leaks in the casing, which may lead to the loss of well fluids to a low pressure, porous zone outside the casing, or otherwise permit an unwanted formation fluid (e.g., water) to enter the well.

Regardless of the specific application, it is often necessary to deploy a patch or straddle to portions of the casing to seal the wellbore from the surrounding subterranean formation.

SUMMARY OF THE DISCLOSURE

The present disclosure is related to downhole tools and, more particularly, to a system and method for deploying casing patches.

In some embodiments, a casing patch assembly is disclosed and may include a setting kit arranged at an uphole end, an upper wedge portion operatively coupled to the setting kit and defining an upper ramp portion, a lower wedge portion arranged at a downhole end and defining a lower ramp portion, and a casing patch axially interposing the upper and lower wedge portions and having a proximal end configured to radially expand upon slidably engaging the upper ramp portion and a distal end configured to radially expand upon slidably engaging the lower ramp portion.

In other embodiments, a method of deploying a casing patch within a casing string is disclosed. The method may include conveying a casing patch assembly to a target location within the casing string, the casing patch assembly including a setting kit arranged at an uphole end, an upper wedge portion operatively coupled to the setting kit, a lower wedge portion arranged at a downhole end, and a casing patch axially interposing the upper and lower wedge portions, linearly actuating a power rod of a deployment device coupled to the setting kit, the power rod being operatively coupled to a mandrel such that movement of the power rod correspondingly moves the mandrel, moving the lower wedge portion with the mandrel, the mandrel being operatively coupled to the lower wedge portion via a locking device, radially expanding a distal end of the casing patch as the distal end slidingly traverses the lower wedge portion, and radially expanding a proximal end of the casing patch as the proximal end slidingly traverses the upper wedge portion.

The features of the present disclosure will be readily apparent to those skilled in the art upon a reading of the description of the embodiments that follows.

DETAILED DESCRIPTION

The present disclosure is related to downhole tools and, more particularly, to a system and method for deploying casing patches.

Disclosed are systems and methods of deploying a casing patch downhole for various wellbore operations or purposes. For instance, in some embodiments, the casing patch can be used to cover or seal a defect or damaged portion in a casing string or other wellbore tubular. In other embodiments, the casing patch may be used to locate and set a gas lift port for gas lift applications. In yet other embodiments, the casing patch may have a profile machined into its inner radial surface and serve as a locating profile set at a known location downhole and used for locking and/or locating various downhole tools. The casing patch forms part of a casing patch assembly that may be deployable using slickline or another type of known wellbore conveyance. The wellbore conveyance delivers the casing patch assembly to a target location at which point the casing patch may be deployed using a linear actuator or the like that axially compresses wedges configured to expand each end of the casing patch against the inner diameter of the casing string. Each expanded end creates a metal-to-metal seal and also an elastomeric seal between its outer diameter and the casing string.

Referring toFIG. 1, illustrated is a well system100that may embody or otherwise employ one or more principles of the present disclosure, according to one or more embodiments. As illustrated, the well system100may include a service rig102that is positioned on the earth's surface104and extends over and around a wellbore106that penetrates a subterranean formation108. The service rig102may be a drilling rig, a completion rig, a workover rig, or the like. In some embodiments, the service rig102may be omitted and replaced with a standard surface wellhead completion or installation. Moreover, while the well system100is depicted as a land-based operation, it will be appreciated that the principles of the present disclosure could equally be applied in any sea-based or sub-sea application where the service rig102may be a floating platform or sub-surface wellhead installation, as generally known in the art.

The wellbore106may be drilled into the subterranean formation108using any suitable drilling technique and may extend in a substantially vertical direction away from the earth's surface104over a vertical wellbore portion110. At some point in the wellbore106, the vertical wellbore portion110may deviate from vertical relative to the earth's surface104and transition into a substantially horizontal wellbore portion112. In some embodiments, the wellbore106may be completed by cementing a casing string114within the wellbore106along all or a portion thereof. As used herein, “casing string” may refer to any downhole tubular or string of tubulars known to those skilled in the art including, but not limited to, wellbore liner, production tubing, drill string, and other downhole piping systems.

The system100may further include a downhole tool116conveyed into the wellbore106. The downhole tool116may be coupled or otherwise attached to a conveyance118that extends from the service rig102. The conveyance118may be, but is not limited to, a wireline, a slickline, an electric line, coiled tubing, or the like. In some embodiments, the device116may be pumped downhole to a target location within the wellbore106using hydraulic pressure applied from the service rig102at the surface104. In other embodiments, the device116may be conveyed to the target location using gravitational forces or otherwise.

As will be described in greater detail below, the downhole tool116may be configured to convey and deploy a casing patch120within the casing string114. In some embodiments, the casing patch120may be configured to seal or otherwise repair a defect or perforation122in the casing string114. In other embodiments, the casing patch120may have a locating profile (not shown) defined or otherwise machined into its inner diameter and the casing patch120may be deployed at a predetermined location within the wellbore106such that subsequent downhole tools or tool strings are able to interact therewith. In yet other embodiments, the casing patch120may define an orifice (not shown) configured to permit gas to pass therethrough such as is used to enhance the lift and production of well fluids to the surface104. Those skilled in the art will readily appreciate the several other applications that the casing patch120may be used for, without departing from the scope of the disclosure.

Even thoughFIG. 1depicts the downhole tool116as being arranged and operating in the horizontal portion112of the wellbore106, the embodiments described herein are equally applicable for use in portions of the wellbore106that are vertical, deviated, or otherwise slanted. Moreover, use of directional terms such as above, below, upper, lower, upward, downward, uphole, downhole, and the like are used in relation to the illustrative embodiments as they are depicted in the figures, the upward direction being toward the top of the corresponding figure and the downward direction being toward the bottom of the corresponding figure, the uphole direction being toward the surface of the well and the downhole direction being toward the toe of the well. As used herein, the term “proximal” refers to that portion of the component being referred to that is closest to the wellhead, and the term “distal” refers to the portion of the component that is furthest from the wellhead.

Referring now toFIGS. 2A-2C, with continued reference toFIG. 1, illustrated are contiguous cross-sectional views of an exemplary casing patch assembly200, according to one or more embodiments. In particular,FIG. 2Adepicts an uphole end202aof the casing patch assembly200,FIG. 2Bdepicts an intermediate portion202bof the casing patch assembly200, andFIG. 2Cdepicts a downhole end202cof the casing patch assembly200. The casing patch assembly200may be a generally tubular or cylindrical structure that may form part of or otherwise be attached to the downhole tool116ofFIG. 1. As illustrated, the casing patch assembly200may be run into the wellbore106(FIG. 1) and otherwise arranged longitudinally within the casing string114.

At its uphole end202a, the casing patch assembly200may include an adapter or a setting kit204configured to couple or attach the casing patch assembly200to a deployment device206(shown in dashed). In some embodiments, the deployment device206may be threaded to the setting kit204at the uphole end202aof the casing patch assembly200. In other embodiments, the deployment device206may be mechanically fastened to the setting kit204using one or more types of mechanical fasteners, such as bolts, screws, setscrews, shearable devices, or the like.

In some embodiments, the deployment device206may be a linear actuator, such as the DPU® tool available through Halliburton Energy Services, Inc. of Houston, Tex., USA. In other embodiments, the deployment device206may be any other downhole device configured to provide a linear force and otherwise facilitate the proper deployment of the casing patch assembly200, as described in greater detail below. For instance, the deployment device206may include, but is not limited to, a mechanical actuator, a hydraulic actuator, a pneumatic actuator, a piezoelectric actuator, an electro-mechanical actuator, combinations thereof, and the like. The deployment device206may have or otherwise include a power rod208configured to be linearly actuated. In exemplary operation, the deployment device206may be configured to axially extend or retract the power rod208, depending on the application and the desired result.

The casing patch assembly200may further include an upper wedge portion210a(FIGS. 2A and 2B), a lower wedge portion210b(FIG. 2C), and a casing patch212that axially interposes the upper and lower wedge portions210a,b. The upper wedge portion210amay be either operatively coupled to the setting kit204or may otherwise form an integral part thereof. The lower wedge portion210bmay be generally arranged at the downhole end202cof the casing patch assembly200. The casing patch212may be slidably engaged with both the upper wedge and lower wedge portions210a,b. In particular, the casing patch212may have a proximal end214a(FIG. 2B) that is slidably engaged with a distal end216aof the upper wedge portion210aand a distal end214b(FIG. 2C) that is slidably engaged with a proximal end216bof the lower wedge portion210b.

The distal end216aof the upper wedge portion210amay define or otherwise provide an inclined surface or one or more upper ramp portions218a(FIG. 2B). Similarly, the proximal end216bof the lower wedge portion210bmay define or otherwise provide an inclined surface or one or more lower ramp portions218b(FIG. 2C). As will be described in greater detail below, the upper and lower ramp portions218a,bmay be configured to slidably engage and thereby radially expand the proximal and distal ends214a,b, respectively, of the casing patch212. The proximal and distal ends214a,bmay be radially expanded until coming into sealing engagement with the inner wall of the casing string114, thereby forming a seal at each end of the casing patch212.

The casing patch assembly200may further include a mandrel220that extends longitudinally within at least a portion of the upper and lower wedge portions210a,band the casing patch212. The mandrel220may be operatively coupled to the power rod208(FIG. 2A) such that axial movement of the power rod208(as actuated by the deployment device206) moves the mandrel220in a corresponding axial direction. In some embodiments, the mandrel220may be coupled to the power rod208via a coupling222. The coupling222may be configured such that one or both of the mandrel220and the power rod208are threadably coupled thereto at each end. In at least one embodiment, however, the power rod208may be coupled to the coupling222using one or more mechanical fasteners224, such as setscrews, bolts, or the like. In other embodiments, however, the coupling222may be omitted and the mandrel220may instead be directly coupled to the power rod208either by threaded engagement or mechanical fasteners.

In some embodiments, the casing patch assembly200may also include a locking device224(FIG. 2C) arranged at the downhole end202c. The locking device224may be coupled or attached to the mandrel220and configured to operatively couple the mandrel220to the lower wedge portion210bsuch that movement of the mandrel220correspondingly moves the lower wedge portion210bin the same axial direction. In operation, the locking device224may be configured to maintain the lower wedge portion210boperatively coupled to the mandrel220until a predetermined axial load provided by the mandrel220is experienced or otherwise assumed across the locking device224. Once the predetermined axial load is assumed by the locking device224, the locking device224may be configured to yield, thereby effectively separating the mandrel220from the lower wedge portion210band otherwise allowing the mandrel220to axially translate unobstructed by the lower wedge portion210b.

In at least one embodiment, the locking device224may be a shearable device, such as a shear pin, a shear ring, or another type of shearable mechanism configured to couple the locking device224to the lower wedge portion210band yield upon experiencing the predetermined axial load. In other embodiments, however, as illustrated inFIG. 2C, the locking device224may encompass a collet assembly. The collet assembly may include a plurality of axially extending fingers226configured to be seated within a groove228defined or otherwise provided in the inner radial surface of the lower wedge portion210b. A bridge support230may be coupled or attached to the mandrel220and may be configured or arranged to bias the fingers226into the groove228such that the fingers226become immovably engaged within the groove228.

The collet assembly may further include a shear sub232that may be coupled or otherwise attached to the mandrel220uphole from the bridge support230. A spacer ring234may interpose or otherwise be arranged radially between the shear sub232and an inner surface of the lower wedge portion210b. In at least one embodiment, the shear sub232may define or provide a shear point236. The shear point236may be an annular groove or thinned portion of the shear sub232that may be configured to fail, separate, or break upon assuming the predetermined axial load as delivered through the mandrel220. In other embodiments, the shear point236may instead be a shear pin, a shear ring, or any other shearable device or mechanism coupling the shear sub232to the spacer ring234and otherwise configured to fail upon assuming the predetermined axial load.

Exemplary operation of the casing patch assembly200will now be provided, in conjunction with additional reference toFIG. 3.FIGS. 2A-2Cdepict the casing patch assembly200in an un-deployed configuration andFIG. 3depicts portions of the casing patch assembly200in a deployed configuration. When it is desired to deploy the casing patch212downhole, the casing patch assembly200is conveyed to a target location within the casing string114. In some embodiments, the target location may be a location within the casing string114in need of the casing patch212to seal a particular portion of the casing string114, such as where the defect or perforation122ofFIG. 1is apparent. In other embodiments, the target location may be a location where it is desirable to place a gas lift port (not shown) as defined in the casing patch212, such as is used to enhance the lift and production of well fluids to the surface104(FIG. 1). In yet other embodiments, the target location may be a location within the casing string114where it is desirable to install a locating profile (not shown) defined or otherwise machined into the inner diameter and the casing patch212.

Upon reaching the target location, the deployment device206may be actuated, thereby linearly actuating the power rod208. In particular, the deployment device206may be actuated such that the power rod208is retracted proximally, or in the uphole direction (i.e., to the left inFIG. 2A). As the power rod208is retracted, the mandrel220is correspondingly moved in the same axial direction as coupled to the power rod208. With reference toFIG. 2C, moving the mandrel220in the uphole direction (i.e., to the left inFIG. 2C) may force the lower wedge portion210bin the same direction as coupled to the mandrel220via the locking device224. In embodiments where the locking device224is a collet assembly, such as the one depicted inFIG. 2C, the mandrel220may be operatively coupled to the lower wedge portion210bvia the fingers226seated within the groove228of the lower wedge portion210band secured therein against removal with the bridge support230.

As the mandrel220moves in the uphole direction, the lower wedge portion210bcorrespondingly moves in the same direction and its proximal end216bslides underneath the distal end214bof the casing patch212. Continued movement of the mandrel220and the lower wedge portion210bin the uphole direction may force the distal end214bof the casing patch212to expand as it traverses or slides up the lower ramp portions218b. In some embodiments, the casing patch212may be made of a material that is less robust than the lower wedge portion210bsuch that the casing patch212is able to radially expand upon slidably interacting with the lower wedge portion210b. In some embodiments, for example, the casing patch212may be made of a mild or low-carbon steel, such as carbon steel1018, and the lower wedge portion210bmay be made of a more robust material, such as hardened steel.

In some embodiments, a lubricant (not shown) may be employed between or otherwise interpose the distal end214bof the casing patch212and the proximal end216bof the lower wedge portion210b, including the lower ramp portions218b. Such a lubricious interface may facilitate a smoother sliding engagement between the distal end214bof the casing patch212and the lower wedge portion210b. In some embodiments, a graphite or TEFLON® substrate or a nitride hard surface may be applied to one or both of the distal end214bof the casing patch212and the lower ramp portions218bor otherwise generally interpose the two components. In other embodiments, one or both of the distal end214bof the casing patch212and the lower ramp portions218bmay be impregnated with a lubricious compound or material, such as oil or graphite, in order that a generally lubricated interface results.

Referring toFIG. 3, with continued reference toFIG. 2C, the distal end214bof the casing patch212expands as it axially traverses the lower ramp portions218buntil engaging the inner wall of the casing string114and thereby generating a metal-to-metal seal between the casing patch212and the casing string114. In some embodiments, the distal end214bmay further include or otherwise provide one or more sealing elements238(shown as first and second sealing elements238aand238b, respectively) configured to provide a sealed interface between the distal end214bof the casing patch212and the casing string114. The first sealing element238amay be an elastomeric or rubber seal arranged within a groove defined in the distal end214bof the casing patch212. In some embodiments, the first sealing element238amay be non-swellable, but in other embodiments, the first sealing element238amay be swellable upon interacting with a particular wellbore fluid, treatment fluid, temperature gradient, wellbore pressure, or the like. The second sealing element238bmay be an elastomeric O-ring or the like. Accordingly, the first and second seals238a,bmay provide redundant sealing capabilities at the interface between the distal end214bof the casing patch212and the casing string114.

The mandrel220and the lower wedge portion210bmay continue to move in the uphole direction until the lower wedge portion210bengages a radial shoulder240defined on the inner surface of the distal end214bof the casing patch212. Upon engaging the radial shoulder240, the axial force assumed by the lower wedge portion210bmay be transferred to the casing patch212, thereby serving to also move the casing patch212in the same axial direction. With reference toFIG. 2B, and continued reference toFIG. 3, as the mandrel220continues to move in the uphole direction (i.e., to the left inFIG. 2B), the casing patch212correspondingly moves in the same direction and its proximal end214bslidably engages the distal end216aof the upper wedge portion210a. In particular, the distal end216aof the upper wedge portion210amay be configured to slide underneath the proximal end214aof the casing patch212.

Continued movement of the mandrel220and the casing patch212in the uphole direction may radially expand the proximal end214aof the casing patch212as it traverses or slides up the upper ramp portions218a. As mentioned above, the casing patch212may be made of a soft material, such as mild steel or the like, such that its proximal end214ais also able to radially expand upon interacting with the upper wedge portion210awhich, similar to the lower wedge portion210b, may be made of a more robust material. Moreover, a lubricant (similar to that mentioned above) may be employed between or otherwise interpose the proximal end214aof the casing patch212and the distal end216aof the upper wedge portion210a, including the upper ramp portions218a, such that a smoother sliding engagement is facilitated between the two components.

Accordingly, the proximal end214aof the casing patch212may be configured to radially expand as it traverses the upper ramp portions218ain the uphole direction. As the proximal end214aexpands, it eventually engages the inner wall of the casing string114, thereby generating a metal-to-metal seal between the casing patch212and the casing string114at that location. Similar to the distal end214bof the casing patch212, the proximal end214amay also include or otherwise provide one or more sealing elements242(shown as first and second sealing elements242aand242b, respectively) configured to provide a sealed interface between the proximal end214aof the casing patch212and the casing string114. The first and second sealing elements242a,bmay be similar to the first and second sealing elements238a,bdescribed above, and therefore will not be described again. Accordingly, the first and second sealing elements242a,bmay provide redundant sealing capabilities at the interface between the proximal end214aof the casing patch212and the casing string114.

The proximal end214aof the casing patch212, as forced by the lower wedge portion210band the mandrel220, may continue to move in the uphole direction until the upper wedge portion210aengages a radial shoulder244defined on the inner surface of the proximal end214a. Upon engaging the radial shoulder244, movement of the mandrel220in the uphole direction is effectively prevented with the lower wedge portion210bengaged with the radial shoulder240at the distal end214bof the casing patch212, and the upper wedge portion210aengaged with the radial shoulder244at the proximal end214aof the casing patch212.

At this point, the power rod208may be configured to increase its axial load on the mandrel220in order to separate the mandrel220from operative engagement with the casing patch212. In particular, the power rod208may be configured to increase its axial load on the mandrel220in the uphole direction until reaching a predetermined axial load of the locking device224. As described above, once the predetermined axial load is assumed by the locking device224, the locking device224may be configured to yield, thereby allowing the mandrel220to separate from the lower wedge portion210bsuch that the casing patch assembly200, minus the casing patch212, may be retrieved to the surface104(FIG. 1).

In embodiments where the locking device224is a collet assembly, as illustrated inFIGS. 2C and 3, the shear point236on the shear sub232may be configured to fail, separate, or break upon assuming the predetermined axial load delivered through the mandrel220. In particular, the shear sub232may further define a radial protrusion246configured to axially engage the spacer ring234. As the predetermined axial load is reached or surpassed, the engagement between the radial protrusion246and the spacer ring234forces the shear sub232to fail at the shear point236. Once the shear sub232fails, the bridge support230may then be able to move axially in the uphole direction and otherwise out of biasing engagement with the plurality of axially extending fingers226. Without the bridge support230forcing the fingers226into the groove228defined in the inner radial surface of the lower wedge portion210b, the fingers226may then be able to flex inward and out of engagement with the groove228. As a result, the collet assembly (i.e., the locking device224) may be disengaged from the lower wedge portion210band free to ascend in the uphole direction while the lower wedge portion210bis left downhole with the casing patch212.

Referring now toFIGS. 4A-4C, with continued reference to the prior figures, illustrated are cross-sectional views of the casing patch212as installed or otherwise deployed within the casing string114, according to one or more embodiments of the disclosure. WhileFIGS. 4A-4Cillustrate at least three exemplary applications of the casing patch212, those skilled in the art will readily appreciate that the casing patch212may be employed in several other downhole applications, without departing from the scope of the disclosure. Moreover, it should be noted that the length and sizing of the casing patch212is not necessarily drawn to scale inFIGS. 4A-4C, and therefore should not be considered as limiting the present disclosure. Rather, those skilled in the art will readily recognize thatFIGS. 4A-4Cmerely depict exemplary applications of the casing patch212, as consistent with the principles of the disclosure.

InFIG. 4A, the casing string114has a defect or hole401(e.g., similar to the defect122ofFIG. 1) formed or defined therein. Unless the defect401is properly sealed, unwanted wellbore fluids402, such as water, may enter into the interior404of the casing string114and be produced to the surface104(FIG. 1). In order to prevent the unwanted fluids402from being produced to the surface104via the defect401, the casing patch212may be deployed within the casing string114, as generally described above. In particular, the casing patch212may be deployed such that it straddles the defect401and is sealed at each end using the metal-to-metal seal between the proximal and distal ends214a,band the inner wall of the casing string114and the sealing elements238a,band242a,b. Once properly deployed and sealed, the casing patch212may prevent the fluids402from entering the interior404of the casing string114.

InFIG. 4B, one or more perforations406may have been formed or otherwise defined in the casing string114. The perforations406may have been formed, for example, through casing perforation operations or a punch tool in order to extract the fluids402from the surrounding formations in a predetermined fashion. As illustrated, the casing patch212may be deployed in the casing string114to generally straddle the perforations406. The casing patch212may have an orifice408defined therein configured to permit the fluid402to pass therethrough at a predetermined flow rate. In some embodiments, the orifice408may have an inflow control device or other flow restrictor arranged therein that is configured to regulate fluid flow into the interior404of the casing string114. In other embodiments, the fluid402may be a gas, either originating from the surrounding formation or injected from the surface104(FIG. 1), and the orifice408may be used as a gas lift port adapted to enhance the lift and production of well fluids within the interior404of the casing string114to the surface104. In such embodiments, the orifice408may be a metered gas lift port and may be hardened so that it is resistant to washout.

InFIG. 4C, the casing patch212may include a locating profile410defined or otherwise machined into its inner diameter. As known to those skilled in the art, locating profiles410may be used such that downhole tools exhibiting a corresponding or matching profile are able to mate therewith. In some embodiments, the casing patch212may be deployed at a predetermined location within the casing string114such that the locating profile410is arranged at a known location for subsequent downhole tools or tool strings to interact therewith. In other embodiments, the locating profile410may be used to replace a damaged profile or locate a new locating profile at a more desirable location within the casing string114.

Referring again toFIG. 2B, in some embodiments, the mandrel220may be an undivided cylindrical rod that extends from the power rod208(or coupling222ofFIG. 2A) to the locking device224in a single, integral piece. In other embodiments, however, the mandrel220may include one or more mandrel extensions248(one shown) that may interpose proximal and distal portions of the mandrel220. In the embodiment ofFIG. 2B, the mandrel extension228may be coupled or otherwise attached to the mandrel220at each end using couplings250aand250b. The couplings250a,bmay provide a threaded or mechanically fastened engagement between the mandrel extension228and the mandrel220at each end, or a combination thereof. Accordingly, in at least one embodiment, the axial length of the mandrel220may be extended by employing one or more mandrel extensions248.

Similarly, in some embodiments, the casing patch212may be an undivided cylindrical tubular that extends from its proximal end214ato its distal end214bin a single, integral piece. In other embodiments, however, the casing patch212may include one or more patch extenders252(one shown) that may interpose the proximal and distal ends214a,bof the casing patch212. As illustrated inFIG. 2B, the patch extender252may be coupled to or otherwise attached to the proximal and distal ends214a,busing coupling interfaces254aand254b. In particular, the patch extender252may be coupled to the proximal end214aof the casing patch212at the first coupling interface254aand coupled to the distal end214bof the casing patch212at the second coupling interface254b. The coupling interfaces254a,bmay be threaded engagements, mechanically fastened engagements, or a combination of the two. In one or more embodiments, at least one of the coupling interfaces254a,bmay be welded or brazed in order to couple the patch extender252to the proximal and/or distal ends214a,b. As a result, the axial length of the casing patch212may be extended by employing one or more patch extenders252.