NO20240870A1

NO20240870A1 - System for expanding a tubular downhole

Info

Publication number: NO20240870A1
Application number: NO20240870A
Authority: NO
Inventors: Matthew Mark Godfrey
Original assignee: Enventure Global Tech Inc
Priority date: 2022-02-04
Filing date: 2024-08-23
Publication date: 2024-08-23
Also published as: GB202416821D0; MX2024009628A; WO2023150306A1; US20250137360A1; AU2023215386A1; EP4473188A1; GB2637591A; AU2023215386B2

Description

SYSTEM FOR EXPANDING A TUBULAR DOWNHOLE

BACKGROUND

[0001] The disclosure relates generally to systems and methods for deploying a tubular in a well and expanding the tubular downhole. The disclosure relates more particularly to an expandable cone and/or a mechanism for temporarily sealing the bottom of the tubular during the expansion of said tubular.

[0002] It is often useful to deploy a tubular inside a well with the tubular having a smaller size than its intended final size and then expand the tubular downhole to its final size. For example, the tubular may be a liner or a patch that is deployed through a base casing and expanded below the base casing to a diameter that would have been too large for deploying the liner or patch through the base casing.

[0003] The tubular can be expanded to its intended final size by passing a cone through the tubular, where the outer diameter of the cone is larger than the inner diameter of the tubular. The cone deforms the tubular by permanently expanding its diameter. While the outer diameter of the cone is larger than the inner diameter of the tubular for the expansion to occur, in some cases, it can be desirable that the cone also has a small size (e.g., so that it can fit inside the tubular before the tubular is expanded) during the deployment of the tubular and the cone. Once downhole, the cone can be expanded to a suficiently large size suitable for expanding the tubular. An example of an expandable cone is described in US pub. no. 2013/0299197.

[0004] The force necessary for passing the cone through the tubular and permanently deforming the tubular can be partially (or sometimes entirely) generated by pumping wellbore fluid at high pressure into a volume sealed inside the tubular so that the wellbore fluid pressure is used to drive a mandrel coupled to the cone through the tubular. For example, in order to seal the volume inside the tubular, a bottom end of the tubular may be connected to a shoe having a port. When the tubular is deployed and ready to be expanded, an obturator (e.g., a ball or dart) can be pumped down and seal the port. An example of a sealable shoe is described in US pub. no. 2021/0189843. Alternatively, the bottom of the tubular can be sealed using an expandable packer. An example of an expandable packer used to seal the bottom of the tubular before its expansion is described in US pub. no.

2011/0011578.

[0005] For maintaining the hydraulic pressure until the cone exits the top of the tubular at the end of its expansion, a pipe is sometimes connected on top of the tubular. The pipe allows for one or more swab cups to move past the top of the tubular and still seal the volume inside the tubular. The pipe, unlike the tubular, may not be expanded. Instead, by using a specific type of threaded connection, the pipe is released upon expansion of the top end of the tubular before the pipe is expanded by the cone and retrieved to the surface. An example of such a releasable pipe is shown in US pub. no. 2019/0316448.

[0006] There is a need in the art for systems and methods for deploying a tubular in a well and expanding the tubular downhole that can facilitate the use of a pressurized wellbore fluid to assist with the expansion of the tubular.

SUMMARY

[0007] The disclosure describes a system for expanding a tubular. The tubular may not include a thread releasable upon expansion of the tubular.

[0008] The system may comprise a body. The body may be sized to be positioned at least partially inside the tubular. The body may include a housing. The body may include a sleeve. The sleeve may have a shoulder. The body may include a releasable retainer configured to hold the sleeve relative to the housing. The releasable retainer may be configured to release the sleeve from the housing. The sleeve may slide relative to the housing after it is released. As such, the body may be collapsible.

[0009] The system may comprise a mandrel. The mandrel may have a longitudinal axis. The mandrel may include a straight portion slidably coupled to the body. The mandrel may include a flared portion having a sloped outer surface. The mandrel may include an end portion having a shoulder. The flared portion may be axially located between the straight portion and the end portion. The mandrel may include a bore configured to flow wellbore fluid from the surface.

[0010] The system may comprise an actuator. The actuator may be disposed in the housing. The actuator may be connected to the mandrel.

[0011] The system may comprise a partially formable cone. The partially formable cone may include a unitary cone ring. The partially formable cone may also include a plurality of cone segments.

[0012] The unitary ring may be disposed around an entire circumference of the mandrel. The unitary cone ring may be fixedly coupled to the body. For example, the unitary cone ring may be fixedly coupled to the shoulder of the sleeve. Translation of the unitary cone ring through the tubular may radially expand the tubular. The unitary cone ring may have an outer diameter larger than an innermost diameter of the tubular before the tubular is expanded. For example, the outer diameter of the unitary cone ring may be larger than the innermost diameter of the tubular so as to cause between 0.1 and 5 percent of expansion strain in the tubular. Preferably, the outer diameter of the unitary cone ring may be larger than the innermost diameter of the tubular so as to cause between 1 and 2 percent of expansion strain in the tubular. The unitary cone ring may be capable of sealing against the tubular. For example, the unitary cone ring may be capable of forming a metal-to-metal seal against the tubular. The unitary cone ring may include a hardened metal capable of plastically deforming the tubular.

[0013] The plurality of cone segments may be distributed around the circumference of the mandrel. The plurality of cone segments may be axially located between the shoulder of the end portion and the unitary cone ring. Some of the plurality of cone segments are located less than one inch from the unitary cone ring. Some of the plurality of cone segments abut against the unitary cone ring. The plurality of cone segments may extend radially to form a portion of the partially formable cone when the mandrel slides relative to the plurality of cone segments. For example, the plurality of cone segments may be slidably coupled to each other and to the flared portion of the mandrel. A conical outer surface of each of the plurality of cone segments may align with a conical outer surface of the unitary cone ring after the plurality of cone segments are radially extended. After the partially formable cone is formed, a gap between the conical outer surface of each of the plurality of cone segments and the conical outer surface of the unitary cone ring may be sufficiently small to prevent complete elastic spring-back of the tubular during expansion of the tubular.

[0014] The system may comprise a casing lock. The casing lock may be mounted to the body. The casing lock may be movable between a first position wherein the casing lock engages the tubular and a second position wherein the casing lock is disengaged from the tubular. The casing lock may be configured to shift from the first position to the second position after the sleeve is released from the housing and has slid relative to the housing so that a section of the tubular may be expanded with the cone.

[0015] The system may comprise a plug. The plug may include a bore connected to the bore of the mandrel. The bore of the plug may include a seat configured to retain an obturator carried by flowing wellbore fluid through the bore of the mandrel. The plug may be releasably coupled to the mandrel. For example, the plug may include a shear pin configured to release the plug from the mandrel after a force applied to the shear pin by the mandrel reaches a predetermined value. The plug may include a piston that is in fluid communication with the bore of the plug. The piston may be configured to set the plug. That is, the plug may have a first configuration wherein the plug is disengaged from an inner wall of the tubular and a second configuration wherein the plug is engaged to and seals against the inner wall of the tubular.

[0016] The system may comprise a first seal between the straight portion of the mandrel and the body. The system may comprise a second seal between the unitary cone ring and the body. The mandrel may include a bore configured to flow wellbore fluid from surface to a volume located inside the tubular. The volume may be at least partially sealed by the first seal, the second seal, and the unitary cone ring. After the plug is set, the volume may be at least partially sealed by the plug.

[0017] The system may comprise a burst disk. The burst disk may be configured to rupture after a hydraulic pressure inside the system reaches a predetermined level and allow the wellbore fluid to flow into the volume sealed by the plug after the plug is engaged to and seals against the inner wall of the tubular.

[0018] In use, the system may be provided in a well. The tubular may be held on the system using the casing lock. An obturator may be carried to the system by flowing wellbore fluid through the bore of the mandrel and the bore of the plug. The obturator may land on the seat so that the bore of the plug is sealed. The wellbore fluid may be pumped to increase hydraulic pressure in the bore of the mandrel and the bore of the plug behind the obturator. The hydraulic pressure may drive the actuator. The actuator may expand the cone. For example, the mandrel may slide relative to the body, and the plurality of cone segments may extend radially. The body may collapse so that the shoulder of the sleeve and the actuator may move the cone inside the tubular and expand a section of the tubular. The piston may set the plug in the expanded section of the tubular. The plug may be released from the mandrel by shearing apart the shear pin after the pressure has reached a predetermined level. The tubular may be released from the casing lock at the end of a stroke of the actuator. The burst disk may rupture after a hydraulic pressure inside reaches a predetermined level and allows the wellbore fluid to flow into the volume sealed by the first seal, the second seal, the unitary cone ring, and the plug. Wellbore fluid may flow from the surface. The cone may translate through the tubular. The expansion of the tubular may continue. After expansion, the plug and an unexpanded portion of the tubular may be milled.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] For a more detailed description of the embodiments of the present disclosure, reference will now be made to the accompanying drawings, wherein:

[0020] Figure l is a sectional view of a lower portion of an expansion system and a liner during deployment within the wellbore, in accordance with a preferred embodiment;

[0021] Figure 2 is a sectional view of the lower portion shown in Figure 1 after a partially formable cone is formed;

[0022] Figure 3 is a sectional view of the lower portion shown in Figure 1 after the partially formable cone has expanded a section of the liner using the same actuator used to form the partially formable cone;

[0023] Figure 4 is a sectional view of the lower portion shown in Figure 1 after a bridge plug is set;

[0024] Figure 5 is a sectional view of the lower portion shown in Figure 1 after the bridge plug is released and during the expansion of the liner assisted by hydraulic pressure;

[0025] Figure 6 is a perspective view of the partially formable cone shown in Figures 1 to 5 before the partially formable cone is formed;

[0026] Figure 7 is a perspective view of the partially formable cone shown in Figures 1 to 5 after the partially formable cone is formed;

[0027] Figure 8 is a perspective view, partially in cross-section, of the expansion system shown in Figures 1 to 5 before the section of the liner has been expanded using the same actuator used to form the partially formable cone; and

[0028] Figure 9 is a sectional view of the bridge plug shown in Figures 1 to 5 after the bridge plug is set in an expanded section of the liner.

[0029] As is customary, the Figures may not be drawn to scale for the sake of clarity.

DETAILED DESCRIPTION

[0030] It is to be understood that the following disclosure describes several exemplary embodiments for implementing different features, structures, or functions of the invention.

Exemplary embodiments of components, arrangements, and configurations are described below to simplify the disclosure; however, these exemplary embodiments are provided merely as examples and are not intended to limit the scope of the invention.

[0031] This disclosure describes aspects of a system for deploying a tubular in a well and expanding the tubular downhole. The system can facilitate the use of a pressurized wellbore fluid to assist with the expansion of the tubular. For example, the system allows the tubular, such as a liner or patch, to be deployed through a base casing already set in the well. The system may then expand that tubular below the base casing such that the tubular has the same or a larger diameter compared to the base casing.

[0032] One aspect of the system is a partially rather than fully formable cone. The partially formable cone comprises movable segments as well as a rigid, unitary portion that is stationary relative to the system body (i.e., the rigid, unitary portion may not move, rotate, or translate relative to the system body). A possible use of the partially formable cone is that the stationary, rigid portion can form a metal-to-metal seal against the tubular, allowing hydraulic pressure to push the partially formable cone, typically upward, and assist with the expansion of the tubular. This metal-to-metal seal against the tubular can eliminate the need for a sealing element, such as a swab cup or other known sealing element that would be located well above the partially formable cone, to drive the partially formable cone (e.g., to pull it upward) and achieve hydraulic expansion. This metal-tometal seal can also eliminate the need for a releasable joint (i.e., a pipe connected on top of the tubular by a thread releasable upon expansion of the tubular) or other known device for maintaining hydraulic pressure until the partially formable cone exits the top of the tubular at the end of its expansion.

[0033] Another aspect of this system is the deployment of a bridge plug or similar packing element, typically below the cone. This bridge plug is set into a section of the tubular that is expanded with the same actuator used to expand the cone and before the assistance of hydraulic pressure for expanding the tubular is made available by sealing the bottom end (e.g., the shoe) of the tubular. Advantageously, an unexpanded section of the tubular located below the section that is expanded, and the bridge plug itself, can be manufactured from easily millable materials. The use of easily millable materials can eliminate an in-hole trip with a specialty reamer or section mill, which would otherwise be required to remove the unexpanded section of the tubular before drilling the next section of the well. Instead, the bridge plug and the unexpanded section of the tubular can be directly milled using the drill bit used to drill the next section of the well.

[0034] The two aspects can be used in conjunction to facilitate the use of pressurized wellbore fluid to assist with the expansion of the tubular. Alternatively, a partially formable cone can be used in an expansion system relying on an obturator closing a port in a shoe to increase pressure in the tubular and thus assist with the generation of the force used to move the cone upward. Furthermore, a bridge plug can also be set in a tubular section that has been expanded with the same actuator used to expand a cone, even if the cone is not partially formable.

[0035] In reference to Figure 1, a lower portion of an expansion system 10 and a liner 12 are illustrated in a run-in-hole configuration during deployment within the wellbore (not shown). The expansion system 10 and liner 12 are deployed to the target depth within the wellbore suspended from a drill string (not shown). The liner 12 is carried in-hole or tied to the expansion system 10 through a set of threaded dogs included in the casing lock 14. The expansion system 10 includes a body 30, and a mandrel 32 that can reciprocate within the body 30 under the action of a j ack or nested set of hydraulic actuators 18.

[0036] The expansion system 10 also includes a first seal 34 that is provided between the body 30 and the mandrel 32 and a second seal 36 that is provided between a partially formable cone 38 and the body 30. The partially formable cone 38 seals against the liner 12.

[0037] In reference to Figures 1 and 2, expansion is initiated at the target depth within the wellbore by pumping a dart or other known obturator 16 (in Figure 2) that lands on a mating seat 28 and forms a seal within the expansion system 10, preventing the flow of wellbore fluid pumped through the drill string and into the bore of the expansion system from escaping the expansion system 10. Pressure may be increased within the expansion system 10, behind the dart 16, causing the jack 18 to translate upward. The jack 18 works to move cone segments 20 of the partially formable cone 38 from the unformed configuration to the formed configuration. A cone ring 22 of the partially formable cone 38 is provided at the leading face of the partially formable cone 38. The cone ring 22 is rigid and unitary and, therefore, not formed and/or unformed. This cone ring 22 of the partially formable cone 38 remains stationary with respect to the body 30 of the expansion system 10 throughout the expansion operation. The cone segments 20 come into contact or near contact with the cone ring 22 of the partially formable cone 38 during its formation. When the partially formable cone 38 is formed, its shape resembles the shape of a standard cone. When formed, the ideal shape of the partially formable cone 38 is a continuous, non-interrupted conical surface formed by the outer surfaces of the cone segments 20 and cone ring 22.

[0038] In reference to Figure 3, after the partially formable cone 38 is formed, the pressure in the wellbore fluid increases until a shear pin, or another releasable retainer (a shear pin 46 is shown in Figure 8) allows a sleeve and a housing that are part of the body 30 to slide relative to one another (a sleeve 48 and a housing 50 are shown in Figure 8). Thus, the jack 18 can continue to stroke once the partially formable cone 38 is fully formed. This continued motion beyond the motion required to form the partially formable cone 38 serves to initiate expansion of the liner. The partially formable cone 38 is translated in its fully formed configuration by a distance of several inches to several feet until full jack stroke is achieved, and the casing lock 14 releases the liner 12 by moving radially inward into a recess provided on the mandrel 32. This translation creates an expanded partial section 42. This expanded partial section 42 provides a location for anchoring a bridge plug or similar packer element with slips 24.

[0039] In reference to Figures 3 and 4, this bridge plug 24 is designed to be set after full j ack stroke is achieved and internal pressure reaches a predetermined level to shear a pin (sheared pin portions 44a and 44b are shown in Figure 9). The pressure causes a piston 52 to move up and set the bridge plug 24 in the expanded liner partial section 42. The bridge plug 24 provides a seal and anchor to contain hydraulic pressure for the purpose of assisting the remaining expansion of the liner. The first seal 34, the second seal 36, the partially formable cone 38, the bridge plug 24, and the dart 16 cooperate to seal a volume located inside the liner 12. This volume is in selective communication with the surface via the bore in the mandrel 32 and in the drill string to which the expansion system 10 is suspended. For example, a burst disk 40 is provided above the seat 18 and is configured to rupture after the pressure inside the bore reaches a predetermined level and allow the wellbore fluid to flow into this volume.

[0040] In reference to Figure 5, once the bridge plug is set, increased pressure in the volume causes a pin (a pin 26 is shown in Figure 9) to shear apart and a retrievable portion of the expansion system 10 to detach from the bridge plug 24. Then, the liner 12 can be expanded using a combination of hydraulic pressure and mechanical pull, similarly to a conventional expansion system.

[0041] Setting the bridge plug 24 in the partial section 42 of the liner 12 allows the unexpanded section 54 of the liner at the bottom of the well to be manufactured from a material that is easily milled using conventional drilling tools because the unexpanded section 54 of the liner at the bottom of the well does not need to resist hydraulic pressure. The bridge plug 24 may also be manufactured from easily millable materials such as composites or thermoplastics. The unexpanded section 54 of the liner at the bottom of the well and the bridge plug 24 can be milled with a conventional drill bit used to drill the next section of the well. Thus, the use of these easily millable materials can eliminate the requirement of an upward milling operation/specialty drilling tool and reduce the number of trips in-hole, saving time and cost.

[0042] In reference to Figures 6 and 7, the cone segments 20 are distributed around the circumference of the mandrel 32, and the cone ring 22 is disposed around the entire circumference of the mandrel 32. The cone segments 20 are located between a shoulder 56 of an end portion of the mandrel 32 and the cone ring 22. The cone ring 22 is attached to the body 30.

[0043] The cone segments 20 can slide relative to each other and relative to a flared portion of the mandrel 32. When the mandrel 32 is retracted inside the body 30 by the jack 18 (shown in Figures 1 to 3), the mandrel 32 slides relative to the cone segments 20, and the cone segments 20 extend radially to form a portion of the partially formable cone 38.

[0044] When formed, the ideal shape of the partially formable cone 38 is a continuous, noninterrupted conical surface formed by the outer surfaces of the cone segments 20 and cone ring 22. In other words, the conical outer surface on each cone segment 20 substantially aligns with the conical outer surface of the cone ring 22. Also, the gap between the conical outer surface of each cone segment 20 and the conical outer surface of the cone ring 22 is sufficiently small to prevent a complete elastic spring-back of the liner 12 during its expansion. For example, the cone ring 22 is preferably located less than one inch and preferably butting right up against the cone segments 20. The alignment of the outer surfaces and/or the small size of the gap facilitates the expansion of the liner 12 by minimizing or at least reducing the force necessary to move the partially formable cone 38 along the liner 12 and expand it.

[0045] The cone ring 22 may be sized to cause anywhere from 0.1% to 5% of plastic expansion strain in the liner 12 in a broad range, with a preferred range of the first l%-2% of plastic expansion strain in the liner 12. The cone segments 20 cause the remaining plastic strain in the liner 12 to arrive at the expanded diameter of the liner 12.

[0046] In reference to Figure 8, the body 30 includes the housing 50 and the sleeve 48. The cone ring 22 is fixedly attached to the sleeve 48 and forms a shoulder 58 of the sleeve 48 against which all of the cone segments 20 will abut after the partially formable cone 38 is formed. In other embodiments, the cone ring 22 may be omitted, and the shoulder 58 of the sleeve 48 is provided at the end of the sleeve 48.

[0047] The shear pin 46 holds the sleeve 48 relative to the housing 50 while the partially formable cone 38 is formed. As the mandrel 32 (which is actuated by the jack 18) retracts inside the body 30, the cone segments 20 are squeezed between the shoulder 58, which is fixedly coupled to the body 30, and the shoulder 56 of the end portion of the mandrel 32, and extend radially.

[0048] After the partially formable cone 38 is formed, the force applied to the cone segments 20 by the mandrel 32 is then transmitted to the shoulder 58 of the sleeve 48, through the sleeve 48, and to the shear pin 46. When a predetermined force level is reached, this force shears apart the shear pin 46. This fracture of the shear pin 46 allows the sleeve 48 to now slide on the housing 50. This movement of the sleeve 48 allows the partially formable cone 38 to move up after the partially formable cone 38 is formed. Because the casing lock 14 is still engaged with the liner 12, the partially formable cone 38 moves through the liner 12 and expands a partial section of the liner 12 using the force generated by the jack 18. The bridge plug 24 can be set in this partial section (i.e., the partial section 42 shown in Figures 4 and 5).

[0049] In reference to Figure 9, the bridge plug 24 includes a deformable seal element 60, a ramp 62 onto which the slips 64 can ride to extend and grip against the inner surface of the liner 12, and extrusion limiters 66. A passageway 68 is located above the mating seat 28 and connects the bore in the bridge plug 24 to a chamber of the piston 52. The piston 52 is used to set the bridge plug 24.

[0050] Before its rupture, the burst disk 40 prevents wellbore fluid pumped from the surface and through the bore in the mandrel 32 from pushing on the partially formable cone 38 or causing radial internal loading with the unexpanded section 54 at the bottom of the liner 12. After the burst disk 40 ruptures, the wellbore fluid pressure pushes on the partially formable cone 38 until the pin 26 shears apart, and the bridge plug 24 detaches from the mandrel 32, allowing a portion of the expansion system 10 to be retrieved to the surface while the bridge plug 24 remains downhole.

[0051] Additionally, the disclosure also contemplates at least the following embodiments:

Embodiment A1

[0052] Embodiment A1 is a system for expanding a tubular. The system generally comprises a body, a mandrel having a longitudinal axis, a partially formable cone, a first seal, and a second seal.

[0053] The mandrel includes a straight portion that is slidably coupled to the body, a flared portion having a sloped outer surface, and an end portion having a shoulder. The flared portion is axially located between the straight portion and the end portion.

[0054] The partially formable cone includes a plurality of cone segments distributed around a circumference of the mandrel and a unitary cone ring disposed around an entire circumference of the mandrel. The plurality of cone segments are axially located between the shoulder of the end portion of the mandrel and the unitary cone ring. The unitary cone ring is fixedly coupled to the body.

[0055] The plurality of cone segments are slidably coupled to each other and to the flared portion of the mandrel. As such, the plurality of cone segments extend radially to form a portion of the partially formable cone when the mandrel slides relative to the plurality of cone segments.

[0056] The unitary cone ring has an outer diameter that is larger than the innermost diameter of the tubular before the tubular is expanded. As such, the translation of the unitary cone ring through the tubular at least partially expands the tubular radially. The unitary cone ring is capable of sealing against the tubular.

[0057] The first seal is located and provides a seal between the straight portion of the mandrel and the body.

[0058] The second seal is located and provides a seal between the unitary cone ring and the body.

[0059] The mandrel includes a bore configured to flow wellbore fluid from the surface to a volume located inside the tubular, wherein the volume is at least partially sealed by the first seal, the second seal, and the unitary cone ring.

Embodiment A2

[0060] Embodiment A2 is a system as described in embodiment Al, wherein the unitary cone ring includes a hardened metal capable of plastically deforming the tubular. For example, the unitary cone ring may be made of the hardened metal.

Embodiment A3

[0061] Embodiment A3 is a system as described in embodiments Al or A2, wherein the unitary cone ring is capable of forming a metal-to-metal seal against the tubular. For example, the unitary cone ring may include a metallic part that has a size and strength suitable for forming a seal against an expandable, metallic tubular as usually encountered in the oil and gas industry.

Embodiment A4

[0062] Embodiment A4 is a system as described in any of embodiments A1 to A3, wherein some of the plurality of cone segments are located less than one inch from the unitary cone ring. For example, all of the plurality of cone segments may be located less than one inch from the unitary cone ring when the partially formable cone is formed. As such, a gap between the conical outer surface of each of the plurality of cone segments and the conical outer surface of the unitary cone ring may be sufficiently small to prevent complete elastic spring-back of the tubular during the expansion of a metallic tubular as usually encountered in the oil and gas industry.

Embodiment A5

[0063] Embodiment A5 is a system as described in embodiment A4, wherein some of the plurality of cone segments, and preferably all of the plurality of cone segments substantially abut against the unitary cone ring when the partially formable cone is formed.

Embodiment A6

[0064] Embodiment A6 is a system as described in any of embodiments Al to A5, wherein the outer diameter of the unitary cone ring is larger than the innermost diameter of the tubular so as to cause between 0. 1 and 5 percent of plastic expansion strain in the tubular. As such, the unitary cone ring substantially contributes to the expansion of the tubular.

Embodiment A7

[0065] Embodiment A7 is a system as described in embodiment A6, wherein the outer diameter of the unitary cone ring is larger than the innermost diameter of the tubular so as to cause between 1 and 2 percent of plastic expansion strain in the tubular.

Embodiment A8

[0066] Embodiment A8 is a system as described in any of embodiments Al to A7, wherein the tubular does not include a top thread releasable upon expansion of the tubular and a section of pipe connected to the tubular by the top thread. As such, the system may be simpler than prior art systems and perform substantially as well.

Embodiment A9

[0067] Embodiment A9 is a system as described in any of embodiments Al to A8, wherein a conical outer surface of each of the plurality of cone segments substantially aligns with a conical outer surface of the unitary cone ring after the plurality of cone segments are radially extended. As such, the outer surface of the partially formable cone is essentially continuous and not stepped.

Embodiment A10

[0068] Embodiment A10 is a system as described in embodiment A9, wherein, after the partially formable cone is formed, a gap between the conical outer surface of each of the plurality of cone segments and the conical outer surface of the unitary cone ring is suficiently small to prevent complete elastic spring-back of the tubular during the expansion of the tubular.

Embodiment B 1

[0069] Embodiment B1 is a system for expanding a tubular. The system generally comprises a body that is sized to be positioned at least partially inside the tubular, a mandrel having a longitudinal axis, an actuator disposed in the housing and coupled to the mandrel, a cone, and a casing lock mounted to the body. The casing lock can be in a first position wherein the casing lock engages the tubular.

[0070] Generally, the body is configured to collapse when the cone is formed. For example, the body includes a housing, a sleeve having a shoulder, and a releasable retainer configured to hold the sleeve relative to the housing. Then, the releasable retainer is configured to release the sleeve from the housing after the cone is formed. After being released, the sleeve can slide relative to the housing.

[0071] Generally, the cone may be an expandable cone. The cone includes a plurality of cone segments distributed around a circumference of the mandrel. The plurality of cone segments are axially located between a shoulder of the body, such as the shoulder of the sleeve, and the shoulder of the mandrel. The plurality of cone segments are configured to extend radially to form at least a portion of the partially formable cone when the mandrel slides relative to the plurality of cone segments. For example, the cone may be a partially formable cone as described in any of the embodiments Al to A10.

[0072] The cone can be formed before the body collapses. Then, the body collapses so that the cone expands a portion of the tubular.

[0073] Then, the casing lock is configured to move from the first position to a second position wherein the casing lock is disengaged from the tubular. Accordingly, the cone can be used to continue expanding the tubular while the casing lock is in the first position and before it moves to the second position.

Embodiment B2

[0074] Embodiment B2 is a system as described in embodiment Bl, further comprising a plug releasably coupled to the mandrel. The plug has a first configuration wherein the releasable plug is disengaged from an inner wall of the tubular and a second configuration wherein the releasable plug is engaged to and seals against the inner wall of the tubular.

Embodiment B3

[0075] Embodiment B3 is a system as described in embodiment B2, further comprising a shear pin configured to release the releasable plug from the mandrel after a force applied to the shear pin by the mandrel reaches a predetermined level.

Embodiment B4

[0076] Embodiment B4 is a system as described in embodiments B2 or B3, wherein the mandrel includes a bore configured to flow wellbore fluid from the surface. The system further comprises a burst disk configured to rupture after a hydraulic pressure inside the bore reaches a predetermined level and allow the wellbore fluid to flow into a volume sealed by the releasable plug after the releasable plug is engaged to and seals against the inner wall of the tubular.

Embodiment B5

[0077] Embodiment B5 is a system as described in any of embodiments B2 to B4, wherein the mandrel includes a bore configured to flow wellbore fluid from the surface. The releasable plug includes a bore connected to the bore of the mandrel. The bore of the releasable plug includes a seat configured to retain an obturator carried by flowing wellbore fluid through the bore of the mandrel. The system further comprises a piston that is in fluid communication with the bore of the releasable plug. The piston is configured to set the releasable plug.

Embodiment B6

[0078] Embodiment B5 is a system as described in any of embodiments B2 to B5, wherein the casing lock is configured to shift from the first position to the second position after the body has collapsed so that the releasable plug is located in a section of the tubular that has been expanded with the partially formable cone. For example, the casing lock is configured to shift from the first position to the second position after the sleeve is released from the housing and has slid relative to the housing.

Embodiment B7

[0079] Embodiment B7 is a method of expanding a tubular. The method comprises the step of holding the tubular on a system for expanding the tubular using a casing lock. The method comprises the step of carrying an obturator by flowing wellbore fluid through a bore of a system for expanding a tubular and landing the obturator on a seat of the system so that the bore of the system is sealed. The method comprises the step of pumping wellbore fluid to increase pressure in the bore of the system behind the obturator. The gradual increase in pressure causes the following sequence automatically. The pressure drives an actuator disposed in a body of the system. A cone coupled to the actuator expands. For example, a mandrel is connected to the actuator. The cone includes a plurality of cone segments distributed around a circumference of the mandrel, the plurality of cone segments being axially located between a shoulder of the body and a shoulder of the mandrel, the plurality of cone segments being configured to extend radially to form at least a portion of the cone when the mandrel slides relative to the plurality of cone segments. Then, after the cone is expanded and the pressure reaches a first predetermined level, the body collapses, allowing the shoulder of the body and the cone to move inside the tubular and expand a portion of the tubular. At the end of a stroke of the actuator, the casing lock releases the tubular. Then, after the actuator has reached the end of its stroke and the pressure reaches a second predetermined level, a plug that is coupled to the mandrel is set in the portion of the tubular that has been expanded. Then, after the plug is set and the pressure reaches a third predetermined level, the wellbore fluid can flow from the bore of the system to a volume inside the tubular and sealed by the plug. Generally, the pressure in the wellbore fluid drives the cone to further expand the tubular. For example, the cone is a partially formable cone that seals against the tubular as is described in any of embodiments Al to A10.

Embodiment B8

[0080] Embodiment B8 is the method described in embodiment B7, performed using a system as described in any of embodiments Bl to B6.

Claims

What is claimed is:

1. A system for expanding a tubular, comprising:

a body;

a mandrel having a longitudinal axis, the mandrel including a straight portion slidably coupled to the body, a flared portion having a slopped outer surface, and an end portion having a shoulder, the flared portion being axially located between the straight portion and the end portion;

a partially formable cone, the partially formable cone including:

a unitary cone ring disposed around an entire circumference of the mandrel, the unitary cone ring being fixedly coupled to the body, the unitary cone ring having an outer diameter larger than an innermost diameter of the tubular before the tubular is expanded, so that translation of the unitary cone ring through the tubular radially expands the tubular; and

a plurality of cone segments distributed around the circumference of the mandrel, the plurality of cone segments being axially located between the shoulder of the end portion and the unitary cone ring, the plurality of cone segments being slidably coupled to each other and to the flared portion of the mandrel so that the plurality of cone segments extend radially to form a portion of the partially formable cone when the mandrel slides relative to the plurality of cone segments,

a first seal between the straight portion of the mandrel and the body; and

a second seal between the unitary cone ring and the body,

wherein the unitary cone ring is capable of sealing against the tubular, and

wherein the mandrel includes a bore configured to flow wellbore fluid from surface to a volume located inside the tubular, the volume being at least partially sealed by the first seal, the second seal, and the unitary cone ring.

2. The system of claim 1, wherein the unitary cone ring includes a hardened metal capable of plastically deforming the tubular.

3. The system of claim 2, wherein the unitary cone ring is capable of forming a metal -to-metal seal against the tubular.

4. The system of claim 1, wherein some of the plurality of cone segments are located less than one inch from the unitary cone ring.

5. The system of claim 4, wherein some of the plurality of cone segments abut against the unitary cone ring.

6. The system of claim 1, wherein the outer diameter of the unitary cone ring is larger than the innermost diameter of the tubular so as to cause between 0.1 and 5 percent of expansion strain in the tubular.

7. The system of claim 6, wherein the outer diameter of the unitary cone ring is larger than the innermost diameter of the tubular so as to cause between 1 and 2 percent of expansion strain in the tubular.

8. The system of claim 1, wherein the tubular does not include a thread releasable upon expansion of the tubular.

9. The system of claim 1, wherein a conical outer surface of each of the plurality of cone segments aligns with a conical outer surface of the unitary cone ring after the plurality of cone segments are radially extended.

10. The system of claim 9, wherein, after the partially formable cone is formed, a gap between the conical outer surface of each of the plurality of cone segments and the conical outer surface of the unitary cone ring is sufficiently small to prevent complete elastic spring-back of the tubular during expansion of the tubular.

11. A method for expanding a tubular, comprising:

providing a system comprising a body, a mandrel, a partially formable cone, a first seal, and a second seal,

the mandrel having a longitudinal axis, the mandrel including a straight portion slidably coupled to the body, a flared portion having a slopped outer surface, and an end portion having a shoulder, the flared portion being axially located between the straight portion and the end portion;

the partially formable cone including:

the first seal providing sealing between the straight portion of the mandrel and the body;

and

the second seal providing sealing between the unitary cone ring and the body,

wherein the unitary cone ring is capable of sealing against the tubular, and

wherein the mandrel includes a bore configured to flow wellbore fluid from surface to a volume located inside the tubular, the volume being at least partially sealed by the first seal, the second seal, and the unitary cone ring;

sliding the mandrel relative to the body and the plurality of cone segments;

extending the plurality of cone segments radially;

flowing the wellbore fluid from the surface to the volume;

translating the unitary cone ring through the tubular; and

expanding the tubular radially at least partially with the unitary cone ring.

12. The method of claim 11, wherein the unitary cone ring includes a hardened metal capable of plastically deforming the tubular.

13. The method of claim 12, comprising forming a metal-to-metal seal against the tubular with the unitary cone ring.

14. The method of claim 11, wherein some of the plurality of cone segments are located less than one inch from the unitary cone ring.

15. The method of claim 14, wherein some of the plurality of cone segments abut against the unitary cone ring.

16. The method of claim 11, comprising causing between 0.1 and 5 percent of expansion strain in the tubular by translating the unitary cone ring through the tubular.

17. The method of claim 16, comprising causing between 1 and 2 percent of expansion strain in the tubular by translating the unitary cone ring through the tubular.

18. The method of claim 11, wherein the tubular does not include a thread releasable upon expansion of the tubular.

19. The method of claim 11, comprising aligning a conical outer surface of each of the plurality of cone segments with a conical outer surface of the unitary cone ring after the plurality of cone segments are radially extended.

20. The system of claim 19, comprising preventing complete elastic spring-back of the tubular located over a gap between the conical outer surface of each of the plurality of cone segments and the conical outer surface of the unitary cone ring during expansion of the tubular.

21. A system for expanding a tubular, comprising:

a body, the body being sized to be positioned at least partially inside the tubular; the body including:

a housing;

a sleeve, the sleeve having a shoulder; and

a releasable retainer configured to hold the sleeve relative to the housing;

a mandrel having a longitudinal axis, the mandrel including a straight portion slidably coupled to the body, the mandrel having a shoulder;

an actuator disposed in the housing, the actuator being connected to the mandrel;

a cone, the cone including a plurality of cone segments distributed around a circumference of the mandrel, the plurality of cone segments being axially located between the shoulder of the sleeve and the shoulder of the mandrel, the plurality of cone segments being configured to extend radially to form at least a portion of the cone when the mandrel slides relative to the plurality of cone segments; and a casing lock mounted to the body, the casing lock being movable between a first position wherein the casing lock engages the tubular and a second position wherein the casing lock is disengaged from the tubular;

wherein the releasable retainer is configured to release the sleeve from the housing after the cone is formed; and

wherein the sleeve can slide relative to the housing after it is released so that the cone expands a section of the tubular.

22. The system of claim 21, further comprising a plug releasably coupled to the mandrel, the plug having a first configuration wherein the plug is disengaged from an inner wall of the tubular and a second configuration wherein the plug is engaged to and seals against the inner wall of the tubular.

23. The system of claim 22, further comprising a shear pin configured to release the plug from the mandrel after a force applied to the shear pin by the mandrel reaches a predetermined value.

24. The system of claim 23, wherein the mandrel includes a bore configured to flow wellbore fluid from surface, the system further comprising a burst disk configured to rupture after a hydraulic pressure inside the bore reaches a second predetermined level and allow the wellbore fluid to flow into a volume sealed by the plug after the plug is engaged to and seals against the inner wall of the tubular.

25. The system of claim 22, wherein the mandrel includes a bore configured to flow wellbore fluid from surface, the plug includes a bore connected to the bore of the mandrel, the bore of the plug includes a seat configured to retain an obturator carried by flowing wellbore fluid through the bore of the mandrel, the system further comprising a piston that is in fluid communication with the bore of the plug, the piston being configured to set the plug.

26. The system of claim 22, wherein the casing lock is configured to shift from the first position to the second position after the sleeve is released from the housing and has slid relative to the housing so that the plug is located in a section of the tubular that has been expanded with the cone.

27. A method for expanding a tubular, comprising:

providing a system comprising a body, a mandrel, an actuator, a cone, and a casing lock; the body being sized to be positioned at least partially inside the tubular; the body including:

a housing;

a sleeve, the sleeve having a shoulder; and

a releasable retainer configured to hold the sleeve relative to the housing;

the mandrel having a longitudinal axis, the mandrel including a straight portion slidably coupled to the body, the mandrel having a shoulder;

the actuator being disposed in the housing, the actuator being connected to the mandrel; the cone being sized to be positioned inside the tubular before being formed, the cone including a plurality of cone segments distributed around a circumference of the mandrel, the plurality of cone segments being axially located between the shoulder of the sleeve and the shoulder of the mandrel, the plurality of cone segments being configured to extend radially to form at least a portion of the cone when the mandrel slides relative to the plurality of cone segments; and

the casing lock being mounted to the body, the casing lock being movable between a first position wherein the casing lock engages the tubular and a second position wherein the casing lock is disengaged from the tubular;

wherein the sleeve can slide relative to the housing after it is released so that the cone expands a section of the tubular;

holding the tubular on the system using the casing lock;

carrying an obturator by flowing wellbore fluid through a bore of the system; landing the obturator on a seat of the system so that the bore of the system is sealed; pumping the wellbore fluid to increase pressure in the bore of the system behind the obturator;

driving the actuator with the pressure;

expanding the cone with the actuator;

collapsing the body after the pressure has reached a first predetermined level so that the shoulder of the sleeve and the cone move inside the tubular and expand a section of the tubular; and

releasing the tubular from the casing lock at the end of a stroke of the actuator.

28. The method of claim 27, the system further comprising a plug releasably coupled to the mandrel, the plug having a first configuration wherein the plug is disengaged from an inner wall of the tubular and a second configuration wherein the plug is engaged to and seals against the inner wall of the tubular, the method further comprising setting the plug in the section of the tubular that has been expanded.

29. The method of claim 28, the system further comprising a shear pin configured to release the plug from the mandrel after a force applied to the shear pin by the mandrel reaches a predetermined value, the method comprising releasing the plug from the mandrel by shearing apart the shear pin after the pressure has reached a second predetermined level.

30. The method of claim 29, wherein the mandrel includes a bore configured to flow the wellbore fluid from surface, the system further comprising a burst disk configured to rupture after the pressure reaches a third predetermined level and allow the wellbore fluid to flow into a volume sealed by the plug after the plug is engaged to and seals against the inner wall of the tubular, the method further comprising:

flowing the wellbore fluid from the bore to the volume;

driving the cone with the pressure in the wellbore fluid to expand the tubular.

31. The method of claim 28, wherein the mandrel includes a bore configured to flow the wellbore fluid from surface, the plug includes a bore connected to the bore of the mandrel, the bore of the plug including a seat configured to retain an obturator carried by flowing the wellbore fluid through the bore of the mandrel flowing through the bore in the mandrel, the system further comprising a piston located in a chamber of the plug that is in fluid communication with the bore of the plug, wherein setting the plug is performed by flowing the wellbore fluid through the bore of the mandrel, through the bore of the plug and into the chamber after landing the actuator.

32. The method of claim 28, shifting the casing lock from the first position to the second position after the sleeve is released from the housing and has slid relative to the housing so that the plug is located in a section of the tubular that has been expanded with the cone.