Method of well decommissioning in through-tubing applications

Abstract

Systems and methods presented herein provide for well decommissioning in through-tubing applications. A carrier for well decommissioning in through-tubing applications, can comprise a perforating assembly that includes at least one of (1) gun charges, and (2) a mechanical cutting device. The carrier can also include a sensor package that determines geometry of tubulars installed in a wellbore, including eccentricity of the tubulars. The carrier can further include an orienting device that orients the carrier to control the perforating assembly. The carrier can also include a roller assembly that allows the carrier to move longitudinally and rotate around a central axis.

Description

CROSS REFERENCE

[0001] This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 63 / 387,853 , filed on Dec. 16, 2022, which is incorporated herein by reference, in its entirety.BACKGROUND

[0002] Downhole mechanical service tools allow for performing operations within a wellbore. When it is time to decommission the well, casing and tubular elements might remain present in the wellbore. It may be difficult or even impossible to remove the casing and tubular elements as part of the decommissioning.

[0003] Perforating charges and mechanical cutters today are typically conveyed in the wellbore on either slickline, wireline, or coiled tubing. Although today live depth control has become common practice in well interventions, limited control is available for the positioning of a gunstring or mechanical tool within the primary tubular element that the toolstring is conveyed in.

[0004] As a result, the ability for the charges or mechanical cutter to create the necessary flow area (e.g., tunnel or slot) is impacted by the lack of control and precision of the toolstring. This might result in an ineffective conduit for fluid. This can also potentially lead to the destruction of other elements present in the construction of the well (e.g., another casing or jewelry element). Such other elements may be inadvertently cut as a consequence of the improper placement of the perforating charge or the mechanical cutter. Conversely, the inability to control the positioning of the bottomhole assembly may prevent the successful cut of specific parts of the wellbore in a surgical manner (e.g., selectively severing the control lines behind a tubing without entirely cutting the tubing in a full 360-dega cut).

[0005] To advance the application of well decommissioning without the removal of the tubing string deployed in a well, new ways of generating connectivity between annuli is required.SUMMARY

[0006] The examples described herein allow for the safe decommissioning of a well without requiring removal of all tubular elements present in a wellbore. One such method of re-gaining flow in a downhole well is to make use of perforation charges (i.e., energetics) or mechanical cutting devices. The mechanical cutting could be applicable to a jetting solution, mechanical solution, ablating solution, or laser. These operations can be planned based on factors such as perforating charge, mechanical cutter standoff, fluid in the well, and geometry of the well (e.g., eccentralization of tubings).

[0007] Systems and methods described herein enable a carrier with a perforating assembly, which can include a series of gun charges or a mechanical cutting sub-assembly to be pressed against a tubular wall (either passively or actively). This can allow an operator to control and minimize the standoff between those elements of the bottomhole assembly and the tubulars. By minimizing the standoff, the perforation can be made more precise.

[0008] The system can include a sensor package. The sensor package can determine the geometry of the tubulars as installed in the wellbore, their eccentricity, and their geometry. Eccentricity can describe the deviation of the tubular well from circular. The sensor package can also obtain real-time feedback on the downhole wellbore conditions and the performance of the bottomhole assembly tools.

[0009] The system can also include an orienting device. The device can orient the carrier actively or passively to control the azimuth of the guns or mechanical cutter. This allows for better targeting specific directions and locations.

[0010] The system can also include a roller assembly. The roller assembly can minimize the friction present on the carrier, allowing the carrier to move either longitudinally or to rotate around its central axis.

[0011] In one example, the roller assembly can allow for the carrier to move up and down in the wellbore and also to move around the circumference of the wellbore.

[0012] The system can provide for delivery of a cutting system, which can include the aforementioned gun charges or mechanical cutting sub-assembly.

[0013] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the embodiments, as claimed.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate various embodiments and aspects of the present invention. In the drawings:

[0015] FIG. 1 is a schematic illustration of an example system for well decommissioning.

[0016] FIG. 2 is an example illustration of a downhole assembly for well decommissioning.

[0017] FIG. 3 is a cross-sectional illustration of a downhole assembly for well decommissioning.

[0018] FIG. 4 is an example flowchart of a method for well decommissioning.DESCRIPTION OF THE EXAMPLES

[0019] Reference will now be made in detail to the present exemplary examples, including examples illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. The described examples are non-limiting.

[0020] FIG. 1 shows an exemplary well site where system components for well decommissioning may be utilized. A formation 110 has a drilled and completed wellbore 120. A derrick 130 above ground may be used to raise and lower components into the wellbore 120 and otherwise assist with well operations.

[0021] A wireline surface system 140 at the ground level includes a wireline logging unit, a wireline depth control system 150 having a cable 160, and a control unit 170. The cable is connected to a connection assembly 180 that may be lowered downhole. The control unit 170 can include a processor, memory, storage, and display that may be used to display and control various operations of the wireline surface system 140, send and receive data, and store data.

[0022] The connection assembly 180 includes equipment for mechanically and electronically connecting a downhole assembly 190 with the cable 160. The cable 160 includes a support wire, such as steel, to mechanically support the weight of the downhole assembly 190 and communication wire to pass communications between the downhole assembly 190 and the wireline surface system 140. The downhole assembly 190, as described in more detail below, is installed below the connection assembly.

[0023] The wireline surface system 140 can deploy the cable 160, which in turn lowers the connection assembly 180 and downhole assembly 190 deeper downhole. Conversely, the wireline surface system 140 can retract the cable 160 and raise the downhole assembly 190 and assembly, including to the surface. The cable 160 is deployed or retracted by the wireline depth control system 5, such as by unwinding or winding the cable 6 around a spool that is driven by a motor.

[0024] The wireline logging unit communicates with the control unit 170 to send and receive data and control signals. For example, the wireline logging unit can communicate data received from the downhole assembly 190 to the control unit 170. The wireline logging unit likewise can communicate data and control signals received from the electronic control system 170 to the downhole assembly 190. In some examples, the wireline logging unit is part of the control unit 170. In other examples, the control unit 170 sends and receives data to and from the downhole assembly 190 directly.

[0025] Although FIG. 1 shows the downhole assembly 190 being operated on a cable 160, the downhole assembly 190 can be attached to other types of conveyance systems, such as coil tubing. Any conveyance system can be used to mechanically support the downhole assembly 190 and mechanically raise or lower it within the wellbore 120. References to a “cable” are intended to be non-limiting, instead encompassing any known conveyance system.

[0026] FIG. 2 is an example illustration of an example downhole assembly 190 for well decommissioning. The downhole assembly 190 can include an upper module 202 and a lower module 204. The downhole assembly 190 can include a carrier 206 that is offset from the housing 220 or positioned inside the housing 220 and offset from the center of the housing's 220 internal cavity. The carrier 206 can be offset using one or more eccentralizers 208. The eccentralizers 208 can be a device that helps to keep a wireline logging tool away from the center of a borehole. The eccentralizer 208 can include a member extending from the carrier in a second direction that is substantially opposite and parallel with the firing direction. In one example, the eccentralizer 208 can include a single bow spring mounted on the outside surface of the logging tool or a set of rubber fingers mounted at the bottom.

[0027] The downhole assembly 190 can include a sensor package (not shown) that can determine the geometry of the tubulars as installed in the wellbore, their eccentricity, and their geometry. The sensor package can also obtain real-time feedback on the downhole wellbore conditions and the performance of the bottomhole assembly tools.

[0028] The carrier 206 can include a charge assembly with one or more gun charges 210 or a mechanical cutting sub-assembly to be pressed against a tubular wall 120 (either passively or actively). The carrier 206 can allow an operator to control and minimize the standoff between the charge assembly of the downhole assembly 190 and the tubulars. By minimizing the standoff, the perforation can be made more precise and reliable.

[0029] In an example, the carrier can include a perforating gun having a tubular gun housing defining an inner volume and extending in an axial direction. A shaped charges 210 can be held in a loading tube, the loading tube being located in the gun housing, the loading tube extending along the axial direction, the shaped charge facing in a firing direction substantially perpendicular to the axial direction, a portion of the gun housing adjacent to the shaped charge in the firing direction being a perforating portion for removal upon firing of the shaped charge.

[0030] The upper module 202 can include a printed wiring assembly 212 that has at least one microprocessor that is connected to a detonator 214 and an electrical connector 216 for connecting a detonator 214 to the firing head, such as a Radio Corporation of America (“RCA”) connector. The electrical connector 216 can be any component that can initiate the gun charges 210 based on a signal from the detonator 214, such as an RCA cable. The downhole assembly 190 can provide electricity from the surface through an electrical wire 218.

[0031] In one example, the initiator assembly 212 can be part of the upper module 202. The initiator assembly 212 can comprise detonator 214 and a detonating cord 146 affixed thereto. The lower module 204 can be adapted for engagement of a wiring harness.

[0032] In another example, the downhole assembly 190 comprises a multi-piece housing, a universal adaptor for engaging a loading tube affixed thereto at the downhole end of the housing, and a universal bulkhead at an up-hole end to engage a firing head. The multi-piece housing has an upper module 202 and lower module 204, each module having an inner and outer surface and an up-hole and downhole end, as well as upper and lower covers that attach to the outer surface of the upper module 202 and lower module 204. A detonator 214 is installed during the manufacturing process and affixed to the outer surface of the upper module 202. A printed wiring assembly 212 is between the upper module 202 and lower module 204.

[0033] The downhole assembly 190 can also include an orienting device (not shown). The orienting device can orient the carrier actively or passively to control the azimuth of the guns or mechanical cutter of the charge assembly. This allows for better targeting specific directions and locations.

[0034] The downhole assembly 190 can also include a roller assembly (not shown). The roller assembly can minimize the friction present on the carrier, allowing the carrier to move either longitudinally or to rotate around its central axis.

[0035] The system can provide for delivery of a cutting system, which can include the aforementioned gun charges or mechanical cutting of the charge assembly.

[0036] FIG. 3 is a cross-sectional illustration of the downhole assembly 190 for well decommissioning in which a carrier 330 is positioned inside and off center a tubular housing 320 of the downhole assembly 190. The carrier 330 can have a perforating gun 340 with a tubular gun housing defining an inner volume and extending in an axial direction. A shaped charge 342 is held in a loading tube. The loading tube is located in the gun housing. The loading tube extends along the axial direction. The shaped charge 342 faces in a firing direction substantially perpendicular to the axial direction. A portion of the gun housing adjacent to the shaped charge 342 in the firing direction is a perforating portion for removal upon firing of the shaped charge. One or more eccentralizer members 350 extend from the perforating gun 340 in a second direction that is substantially opposite and parallel with the firing direction. A first retainer part extends from an outer surface of the gun housing adjacent to the perforating portion. A second retainer part extends from the outside of the gun housing adjacent to the perforating portion.

[0037] FIG. 4 is an example flowchart of a method for well decommissioning. At stage 410, the downhole assembly 190 can be lowered into a wellbore. The downhole assembly 190 can include a carrier with a perforating assembly. The carrier can be attached to a slickline, wireline, coiled tubing, or other line. An operator can control the lowering of the carrier. The roller assembly of the carrier can assist in traversing downward through the wellbore and around obstacles.

[0038] At stage 420, a sensor assembly of the downhole assembly 190 can determine the geometry of the tubulars as installed in the wellbore. This can include determining their eccentricity.

[0039] At stage 430, an orienting device can press the carrier against a tubular wall. The orienting device can be on an opposite side of the carrier from the perforating assembly, in an example.

[0040] At stage 440, either during, prior to, or after stage 430, the operator can move the carrier device into position for the perforation. With a roller assembly, the operator can move the carrier device longitudinally and around its central axis.

[0041] When the carrier is in position, at stage 450, the operator can detonate the perforating charge.

[0042] Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is understood that the control functionality can be carried out be a processor-enabled device, which can be separate from or part of the slot cutter, depending on the example. Also, the terms slot cutter and cutting device are used interchangeably. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

Claims

1. A carrier for well decommissioning in through-tubing applications, comprising:a perforating assembly that includes at least one of (1) gun charges, and (2) a mechanical cutting device;a sensor package that determines geometry of tubulars installed in a wellbore, including eccentricity of the tubulars; andan orienting device that orients the carrier to control the perforating assembly.

2. The carrier of claim 1, wherein the perforating device is oriented to minimize standoff between the carrier and a tubular being perforated.

3. The carrier of claim 1, wherein the orienting device is controlled by an operator.

4. The carrier of claim 1, wherein the sensor package obtains real-time feedback of the wellbore, the real-time feedback being used by the orienting device.

5. The carrier of claim 1, wherein the orienting device actively controls an azimuth of the gun charges.

6. The carrier of claim 1, wherein the orienting device passively controls an azimuth of the mechanical cutting device.

7. The carrier of claim 1, wherein sensor package provides real-time monitoring of the tubulars in the wellbore, and wherein the orienting device uses the real-time monitoring in controlling the perforating assembly.

8. The carrier of claim 1, further comprising a roller assembly that allows the carrier to move longitudinally and rotate around a central axis 9. A method for well decommissioning in through-tubing applications, comprising:lowering a carrier with a perforating assembly into a wellbore.determining, with a sensor assembly of the carrier, the geometry of a tubular installed in the wellbore;with a roller assembly, moving the carrier device longitudinally and around a central axis;with an orienting device, pressing the carrier against a wall of the tubular; anddetonating the perforating charge.

10. The method of claim 9, wherein the orienting device is on an opposite side of the carrier from the perforating assembly.

11. The method of claim 9, wherein determining the geometry includes determining an eccentricity of the tubular.

12. The method of claim 9, wherein the carrier is attached to one of a slickline, wireline, and coiled tubing.

13. The method of claim 9, wherein the roller assembly of the carrier assists the carrier in traversing downward through the wellbore and around obstacles.

14. The method of claim 9, wherein the sensor assembly provides real-time monitoring information to the orienting device, and wherein the orienting device uses the real-time monitoring information to press the carrier against the tubular.

15. A non-transitory, computer-readable medium containing instructions for well decommissioning in through-tubing applications, the instructions causing a processor to execute stages comprising:lowering a carrier with a perforating assembly into a wellbore.determining, with a sensor assembly of the carrier, the geometry of a tubular installed in the wellbore;with a roller assembly, moving the carrier device longitudinally and around a central axis;with an orienting device, pressing the carrier against a wall of the tubular; anddetonating the perforating charge.

16. The non-transitory, computer-readable medium of claim 15, wherein the orienting device is on an opposite side of the carrier from the perforating assembly.

17. The non-transitory, computer-readable medium of claim 15, wherein determining the geometry includes determining an eccentricity of the tubular.

18. The non-transitory, computer-readable medium of claim 15, wherein the carrier is attached to one of a slickline, wireline, and coiled tubing.

19. The non-transitory, computer-readable medium of claim 15, wherein the roller assembly of the carrier assists the carrier in traversing downward through the wellbore and around obstacles.

20. The non-transitory, computer-readable medium of claim 15, wherein the sensor assembly provides real-time monitoring information to the orienting device, and wherein the orienting device uses the real-time monitoring information to press the carrier against the tubular.

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