Downhole Fish Grabbing Tool

Abstract

A downhole fishing tool includes a main body, a hollow cover, an imaging sub-system, a movable claw, and a sling hub. The main body also includes a barrel in which multiple fluid ports are defined. The hollow cover is arranged on the axis and has an inner surface forming an annular space between the barrel of the main body and the inner surface of the cover. The fluid ports are aligned with the cover. The imaging sub-system includes a camera arranged in a compartment defined in the main body. The movable claw and sling hub are mounted on a second end of the main body. The movable claw includes at least two arms bendable at an elbow joint and having s a magnet section for engaging a fish. The sling hub is arranged between the at least two arms and moves the movable claw between an open and closed position.

Claims

1. A downhole fishing tool comprising: a main body having a first end and a second end defining a first axis; the main body comprising: a barrel arranged between the first end to the second end of the main body, the barrel having an outer surface with a barrel diameter; a fluid line defined in the main body, a plurality of fluid ports defined in the outer surface of the barrel; wherein the plurality of fluid ports are equally spaced around the outer surface of the barrel; and a plurality of port conduits, wherein each port conduit in the plurality of port conduit fluidly connects a corresponding fluid port in the plurality of fluid ports to the fluid line of the main body; a compartment defined between the barrel and the second end of the main body, wherein the main body defines a hole extending from the second end to the compartment, wherein the hole is centered on the axis; a hollow cover arranged on the axis having an inner surface defining an interior space extending from a closed end of the cover to an open end of the cover, wherein at least a portion of the main body is arranged in the interior space, wherein the plurality of fluid ports are aligned with the cover; wherein the outer surface of the barrel and the inner surface of the hollow cover define an annular space; an imaging sub-system; the imaging sub-system comprising: a camera arranged in the compartment of the main body; wherein an optical lens of the camera is centered on the axis and faces away from the first end of the main body; and a transparent shell, wherein the transparent shell encloses the camera; wherein the transparent protective shell fluidically isolates the camera; a movable claw mounted on the second end of the main body, wherein the claw centered on the axis; and a sling hub slidably mounted to the second end of the main body, wherein the sling hub is centered on the axis.

2. The tool according to claim 1, wherein the claw comprises at least two movable fingers, wherein the claw is centered on the axis.

3. The tool according to claim 1, wherein the main body is configured to be positioned in a wellbore.

4. The tool according to claim 1, wherein the plurality of fluid ports are configured to discharge a cleaning fluid.

5. The tool according to claim 4, wherein the plurality of fluid ports are configured to radially discharge the cleaning fluid.

6. The tool according to claim 1, herein the claw comprises the sling hub.

7. The tool according to claim 1, wherein the protective shell extends into the hole of the second end of the main body.

8. The tool according to claim 1, the movable claw comprising: multiple arms, each arm of the multiple arms comprising: a base connected to the second end of the main body; a clamping finger connected to the base, the clamping finger having a connection end and a tipped end; wherein the tipped end is free and movable relative to the base; wherein each clamping finger comprises a magnet section between the connection end and the tipped end; and an elbow joint connecting the base and the clamping finger, wherein the connection end of the clamping finger is connected to the elbow joint.

9. The tool according to claim 8, wherein the sling hub is arranged between multiple arms.

10. The tool according to claim 8, wherein the multiple arms are arranged equidistant from the axis.

11. The tool according to claim 8, wherein the second end of the main body comprises a face and an edge defining the face, wherein the hole of the second end of the main body extends through the face.

12. The tool according to claim 11, wherein the multiple arms connect to the face of the second end of the main body, adjacent the edge of the second end of the main body; wherein the base of each arm in the multiple arms extends parallel to the axis.

13. A downhole fishing tool comprising: a main body having a first end and a second end defining a first axis; the main body comprising: a barrel arranged between the first end to the second end of the main body, the barrel having an outer surface with a barrel diameter; a plurality of fluid ports defined in the outer surface of the barrel; a compartment defined between the barrel and the second end of the main body, wherein the main body defines a hole extending from the second end to the compartment, wherein the hole is centered on the axis; a hollow cover arranged on the axis having an inner surface defining an interior space and extending from a closed end of the cover to an open end of the cover, wherein the plurality of fluid ports are aligned with the cover; wherein the outer surface of the barrel and the inner surface of the hollow cover define an annular space; an imaging sub-system comprising: a camera arranged in the compartment of the main body; wherein an optical lens of the camera is centered on the axis and faces away from the first end of the main body; and a transparent shell, wherein the transparent shell encloses the camera; wherein the transparent protective shell fluidically isolates the camera; a movable claw mounted on the second end of the main body, the movable claw comprising: at least two arms, each arm comprising: a base connected to the second end of the main body; a clamping finger connected to the base, the clamping finger having a connection end and a tipped end; wherein the tipped end is free and movable relative to the base; wherein each clamping finger comprises a magnet section between the connection end and the tipped end; and an elbow joint connecting the base and the clamping finger, wherein the connection end of the clamping finger is connected to the elbow joint; a sling hub mounted to the second end of the main body, wherein the sling hub is arranged between the at least two arms.

14. The tool according to claim 13, wherein the sling hub is centered on the axis.

15. The tool according to claim 13, wherein the sling hub defines an aperture, wherein the aperture of the sling hub is centered on the axis.

16. The tool according to claim 15, wherein the aperture aligns with the hole defined in the second end of the main body and aligns with the lens of the camera.

17. The tool according to claim 15, wherein the sling hub comprises: a hub body mounted to the second end of the main body; and a contact face oriented away from the main body; wherein the aperture extends through the hub body and contact face.

18. The tool according to claim 13, wherein the magnet sections of the at least two fingers are arranged adjacent the connection end of the clamping fingers of the at least two arms.

19. The tool according to claim 13, wherein the magnet sections of the at least two arms are arranged adjacent to the sling hub.

20. The tool according to claim 13, further comprising a plurality of linkages, wherein each linkage of the plurality of linkages extends from the hub body to a corresponding arm of the at least two arms.

21. The tool according to claim 13, wherein the tipped end of the at least two fingers are separated by a distance of about 1 inch to about 6 inches.

22. The tool according to claim 13, wherein the at least two arms are arranged on an edge of the second end of the main body.

23. The tool according to claim 22, wherein the at least two fingers are arranged equally around the edge of the second end of the main body.

24. The tool according to claim 13, wherein the at least two arms have a length of 5 inches to about 30 inches.

25. The tool according to claim 13, wherein at least a portion of the main body is arranged in the interior space of the cover.

26. The tool according to claim 13, wherein the plurality of fluid ports of the main body are equally spaced around the outer surface of the barrel.

27. The tool according to claim 13, wherein the main body further comprises a fluid line defined in the main body and a plurality of port conduits, wherein each port conduit in the plurality of port conduit fluidly connects a corresponding fluid port in the plurality of fluid ports to the fluid line of the main body.

28. A method comprising: imaging, by an imaging sub-system of a downhole fishing tool arranged in a wellbore, the downhole environment of a wellbore, a fishing tool into a wellbore, wherein a movable claw of the fishing tool is in an open position with first diameter; identifying a debris item in the wellbore using the imaging sub-system; and prompting the claw to move from the open position to a closed position, wherein the movable claw of the fishing tool has a second diameter in the closed position, wherein the second diameter is less than the first diameter.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0024] FIG. 1 is a front view of a debris retrieval system having a fishing tool.

[0025] FIG. 2 is a cross-sectional front view of the fishing tool with an imaging sub-system and movable claw.

[0026] FIG. 3 is a cross-sectional view of the fishing tool.

[0027] FIGS. 4A and 4B are cross-sectional front views of the claw of the fishing tool with an imaging sub-system, sling hub, and clamping fingers, in the open position and close position, respectively.

[0028] FIG. 5 is a bottom view of the fishing tool.

[0029] FIGS. 6A-D are cross-sectional front views of the debris retrieval system deployed in a wellbore.

[0030] Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

[0031] The disclosure relates to downhole fishing system with a fishing device (tool) that can diagnose, retrieve, and remove debris from the wellbore in a single run. The fishing device includes main body housing a imaging sub-system for diagnosing and imaging the wellbore environment downhole of the device. The device can flow a clean, transparent fluid through an annular gap between the main body and a cover to increase the transparency of the surrounding fluid and to clean a protective cover encasing a camera of the imaging sub-system. The imaging sub-system can zoom in or out to generate multiple downhole images for diagnosing whether a fish (e.g., debris, wire, lost tool) exists and whether the fishing device can capture the fish. The fishing tool is deployed using a coiled tubing or E-line. The device also includes a movable claw and slidable sling hub mounted to the downhole end of the main body. The movable claw has an open position and a close position. In the open position, a fish can enter into the claw and contact the sling hub. Once the sling hub contacts the fish the device continues to move downhole and the fish applies a mechanical (uphole) force against the sling hub. The sling hub moves uphole relative to the main body, moving the claw into the closed position to retain the portion of the fish in the claw.

[0032] The fishing tool can be used to retain a portion of the fish or a part of the fish inserted into the claw. For example, the fishing tool can engage and remove a tool with a fishing neck by the fishing neck, or may engage and retrieve a fish without a fishing neck (e.g. parted tool, slickline, wire, cable, handheld tool, or tubing), by the portion of the fish inserted into the claw and retained by the claw in the closed position. A power magnet on arms of the claw can latch onto a fish of ferromagnetic or magnetic material (e.g., wires) to further retain a fish in the claw when closing the claw and when removing the claw with the clamped fish. The claw can engage, clamp, and latch fishes with a fish neck or outer dimension of up to 6 inches (e.g., between 1.5 inches and 4 inches). Where the fish is flexible, collapsible, or condensable, some claw can expand from the open position to an expanded position, then to a closed position to capture and compress the flexible fish. Additionally, fishes made from soft or penetrable material (e.g., a sponge or tangle of wires) may also be retrieved using the claw despite all dimensions being greater than the diameter of the claw in the open position. For example, the claw may insert pointed, bladed, or barbed tipped fingers into the fish and move from the open position to the closed position to further clamp the soft fish.

[0033] FIG. 1 is a front view of a debris retrieval system 100 for diagnosing, engaging, and retrieving debris in a single run. The system 100 includes a fishing tool 102 connected to a line 104 (e.g., an E-line or coiled cable) and a fluid source 106 connected to the fishing tool 102 b a fluid conduit 108. A fluid pump 110 conveys clean, transparent fluid from the fluid source 106 to the tool 102. Additives can be added to the fluid source by injection into the fluid conduit or fluid source through one or more additive sources. The tool 102 expels the transparent fluid from the fluid source 106 to clean the tool 102 in use and to increase the transparency of fluid in a wellbore casing 112 (e.g., fluid adjacent the tool). The wellbore casing 112 is arranged in a wellbore 114 defined in a formation 116.

[0034] The tool 102 has an uphole end 118 (first end, proximal end) and a downhole end 120 (second end, distal end). A tool axis 122 is defined by the uphole and downhole ends 118, 120 of the tool 102. The casing 112 and the tool 102 are centered on the tool axis 122. The wellbore 114 is also centered on the tool axis 122. In this configuration, the tool 102 is arranged concentrically to the casing 112 and the casing is arranged concentrically to the wellbore 114. The tool 102 translates axially along the axis 122 to move uphole or downhole within the casing 112.

[0035] The system 100 includes a computer sub-system 124 operably connected to the tool 102. The tool 102 is operable to be controlled by the computer sub-system. The computer sub-system includes a controller, one or more processors, and a non-transitory computer-readable medium storing instructions executable by the one or more processors to perform operations. The operations can include imaging, by the imaging sub-system of the downhole fishing tool arranged in a wellbore, the downhole environment of a wellbore. The operations can also include identifying a debris item (fish) in the wellbore, determining, by the imaging sub-system, that the fish is adjacent the sling hub, and prompting device to move in a first, downhole direction to move the claw of the tool from the open position to a closed position.

[0036] FIG. 2 is a cross-sectional front view of the downhole fishing tool 102 having a main body 130 having a first end 132 (uphole end, proximal end) and a second end (downhole end, distal end). In some cases, the first end and the second end of the main body defines the tool axis. The main body 130 is centered on the tool axis 122. The main body 130 includes a barrel 136 arranged between the first end and the second end 134 of the main body 130. The barrel 136 has an outer surface 138 with a barrel diameter d.sub.b.

[0037] The main body 130 also includes multiple (e.g., a plurality, at least two) fluid ports 140 defined in the outer surface 138 of barrel 136. The fluid ports 140 are spaced equally around the outer surface 138 of barrel 136 and are equidistant from the tool 102 axis 122. the fluid ports can open and close based on prompts from a computer sub-system 124 (FIG. 1). In some cases, the ports are openings). Some ports can be electronically controlled, passively controlled valves (e.g., pressure valves or check valves), and/or any other valves or other fluid control ports. Some ports can include rotatable nozzles that can direct a jet or flow of fluid from the fluid source to a downhole environment, external to the main body or tool (e.g., an environment, or wellbore environment). Each port 142 of the multiple ports 140 are arranged on the surface 138 of the barrel 136 and convey, discharge, expel, flow, or guide fluid from the fluid source 106 (FIG. 1) radially outward from the barrel 136. In the tool 102, the radial direction is orthogonal to the tool axis 122. In some main bodies, the ports may direct fluid at an angle greater than 90 degrees or less than 90 degrees relative to the axis. For example, the ports may be oriented so that fluid (arrows) flows from the port at a 15-, 30-, 45-, or 60-degree angle relative to the tool axis. In some cases, each port has a rotatable, directable nozzle which can be individually oriented to a predetermined angle. The directable nozzles may be oriented at the same angle and direction or may be oriented at a different angle and/or direction.

[0038] The main body 130 also includes a fluid line 144 (FIG. 3) defined in the main body 130. The fluid line 144 (FIG. 3) fluidly connects the fluid source 106 (FIG. 1) to the multiple fluid ports 140. The main body includes multiple port conduits 146c (e.g., a plurality of port conduits or at least two port conduits). Each port conduit 148 of the multiple port conduits 146 fluidly connect a corresponding fluid port 142 in multiple fluid ports 140 to the fluid line 144 of the main body 130.

[0039] The main body 130 also includes (defines) a compartment 150. The compartment 150 is arranged between barrel 136 and the second end of the main body 130. In some cases, the compartment is defined in the second end of the main body. A hole 152 defined in the second end 134 of the main body 130 extends from a face 154 of the second end 134 to the compartment 150. The hole 152 may be empty or may be filled by a transparent material to fluidically isolate the compartment from the wellbore environment. The hole 152 is centered on the tool axis 122.

[0040] The device 102 has a hollow cover 160 centered on the axis 122. The hollow cover can be a cylindrical cover with a circular, oval, or elliptical cross-sectional area. The hollow cover 160 connects to the line 104 and extends from the first end 118 of the tool 102. In some cases, a closed end of the hollow cover forms the first end of the tool. In some cases, the main body extends from and/or forms the first end of the tool. The hollow cover 160 covers a portion or section of the main body 130 (e.g., a majority of the main body). The hollow cover 160 covers the fluid ports 140 defined in the surface 138 of the barrel 126. In this configuration, the fluid ports 140 project or discharge a transparent, clean fluid 155 radially. The discharged fluid 155 contacts the cover 160 and flows downhole towards the second end 134 of the tool 102.

[0041] The tool 102 also includes an imaging sub-system 170 for imaging and diagnosing a fish presence in the wellbore casing 112. The imaging sub-system 170 includes a camera 172 arranged in the compartment 150 of the main body 130. The camera 172 optical lens 174 centered on the axis 122. The camera 172 and lens 174 and face away from the first end 132 of the main body 130. The imaging sub-system 170 also includes a transparent shell 176. The transparent shell 176 encloses the camera 172 so that the camera 172 is fluidically isolated from the wellbore environment.

[0042] A movable claw 180 of the tool 102 is mounted on the second end 134 of the main body 130. The claw 180 is centered on the tool axis 122. The claw is axially and rotationally fixed to the main body 130 and cover 160. A sling hub 181 of the tool 102, for example a hollow cylindrical shaft, is also connected to the second end 134 of the main body 130. The sling hub is centered on the axis 122 and movable along the axis when receiving a force from a fish. The sling hub may be biased in the open position.

[0043] FIG. 3 is a cross-sectional view of the tool 102 taken at the fluid ports 140 of the main body 130, in a plane orthogonal to the tool axis 122. In the tool 102, the fluid ports are arranged at an axial location along the axis and extend radially (e.g., are arranged on a single plane orthogonal to the tool axis). In some tools, the fluid ports may be arranged at different axial locations along the tool axis.

[0044] The cover 160 encompass or encircles the main body 130 and the main body 130 is arranged concentrically within the cover 160. The cover 160 has an inner surface 162 and an outer surface 164. The inner surface 162 defines an interior space 166. The interior space 166 of the cover 160 extends from a closed end (first end, uphole end, proximal end) of the cover 160 to an open end (second end, downhole end, distal end) of the cover 160. The cover has a cover diameter de, measured from the inner surface of the cover. The cover 160, barrel 136, and first end 132 of the main body are made of or include a first material, for example a low steel alloy. The second end 134 of the main body 130 is made of or includes a second material, different from the first material. In some cases, the second material is an optically transparent material that passes light. In some cases, the second material is a high index glass, for example crown glass. Some second ends include a section formed by the second material and another section formed by the first material or by a third material, different from the first and second material.

[0045] The barrel 136 of the main body 130 has a diameter d.sub.b, measured from the outer surface 138 of the barrel 132. At least a portion of the barrel 136 is arranged concentrically within the interior space 166 of the cover 160. The barrel diameter d.sub.b is less than the cover diameter d.sub.c. The cover 160 is aligned with the fluid ports 140 so that the inner surface 164 of the cover 160 guides the fluid discharged from the fluid ports 140.

[0046] The inner surface 164 of the cover 160 is distanced from the outer surface 138 of the barrel 136 by a gap of distance d.sub.gap. In this configuration, the outer surface 138 of the barrel 136 of the main body 130 and the inner surface of the cover 160 define an annular space 200. The annular space 200 is fluidically connected to the fluid ports 140 so that fluid flows from the fluid ports 140 through the annular space 200. The gap distance d.sub.gap is equal (d.sub.c-d.sub.b)/2 (or the difference between the radius of the barrel and the radius of the cover). In the tool 102, the gap distance d.sub.gap is also equal to the difference between the distance from the tool axis 122 to the inner surface 164 of the cover 160 and the distance from the tool axis 122 to the outer surface of the barrel 136.

[0047] The fluid conduits 146 extend radially from the fluid line 144. In some cases, the fluid conduits extend radially and axially (towards the second end of the main body) from the fluid line. The fluid line 144 and fluid conduits 146 receive fluid from the fluid source 106 (FIG. 1). The fluid pump 110 (FIG. 1) conveys fluid at a rate of up to about 7 BPM (e.g., about 3BPM to about 5BPM).

[0048] FIGS. 4A and 4B are cross-sectional front views of the second end 120 of the tool 102 with the claw 180 in the open position and closed position, respectively. A portion of the main body 130, extends from the interior space 166 (FIG. 3) of the cover 160 towards the second end 120 of the tool 102. The second end 134 of the main body 130 is not aligned with or covered by the cover 160.

[0049] The second end 134 of the main body 130 defines the compartment 150. The camera 172 of the imaging sub-system 170 is arranged in the compartment 150. The camera 172 includes or is attached to a lens 174 configured to zoom or magnify the image taken or generated by the camera 172. The magnified image may be a downhole view of the wellbore casing 114 through the hole 152 in the second end 134 of the main body 130.

[0050] The imaging sub-system 170 also includes the protective shell 176 arranged around the camera 172 to isolate the camera 172 and/or other electronics from fluid in the wellbore environment. The transparent shell can extend through (into) the hole 152 to block fluid from entering the hole 152. The shell can also extend into a central aperture of the sling hub. The protective shell 176 forms the second end 134 of the main body 130 and is made of a transparent material. The transparent material can be high index glass (e.g., crown glass). In some cases, the transparent shell forms a portion of the second end of the main body.

[0051] The movable claw 180 of the tool 102 includes multiple arms 182 (a plurality of arms, at least one arm, at least two arms). Each arm 184 of the multiple arms 180 has a base 185 extending from and mounted to the second end 134 of the main body 130. The multiple arms 182 are arranged at or adjacent to the edge 156 of the second end 134 of the main body. The arms 180 mount or connect to the face 154 of the second end 134 of the main body 130 or are integral with the face 154 of the main body 130. The base 185 of each arm 184 extends parallel axially, parallel to the tool axis 122. in some tools, the base extends at an angle relative to the tool axis, for example 15, 30, or 60 degrees relative to the tool axis. The multiple arms can grip, center, and retain fish in the wellbore. Each arm 184 also includes a clamping finger 186 connected to the base 185 by a joint 188 or hinge. The clamping finger has a connection end 190 and a tipped end 192. The tipped end 192 is free and movable relative to the base 185 and together define a finger (claw) diameter d.sub.f (or distance). The finger diameter d.sub.f increases and decreases as the tipped ends 192 of the clamping fingers 186 move about the joint 188. The finger diameter d.sub.f increases where the tipped ends 192 move radially from the axis 122 and the finger diameter d.sub.f decreases where the tipped ends 192 move radially towards the axis. The clamping fingers 186 of the multiple arms 182 The claw 180 of the tool 102 has four arms 182 arranged equidistant from the axis 122 and equally spaced about the axis 122 to form a square cross section. In some tools, the claw has more than four or less than four arms. For example, some tools have a first arm, a second arm, and a third arm arranged with a triangular cross section.

[0052] The arms are made of Forged steel. The clamping fingers may include alloy steel and/or stainless steel forgings. In some cases, the tipped ends of clamping fingers include a resilient material, for example alloy steel and/or stainless steel forgings.

[0053] The arms have a length of about 5 inches to about 30 inches. The bases have a length of about 2 inches to about 10 inches. The clamping fingers have a length of about 3 inches to about 20 inches (in). The second end of the main body can extend about 1 in to about 15 in along the axis and have a diameter of about 2 in to about 10 in. The movable claw can be sized (e.g., have dimensions) based on the size of the wellbore and/or anticipated fish type and size.

[0054] Each clamping finger 186 includes a magnet section 194 arranged between the connection end 190 and the tipped end 192. The magnet section 194 includes at least one magnet 196. In some tools, the at least one magnet is a power magnet or an electromagnet. The magnet section 194 attracts and latches metal objects and ferromagnetic objects to the claw 180. For example, the magnet section can latch or further engage loose steel materials (e.g., wire or parted steel). The magnet section may be electrically power so that the strength of the magnet increases or decreases as required to latch a fish to the claw. In some cases, a computer sub-system 124 controls the strength or attractive force of the magnet section.

[0055] In some cases, the clamping fingers include multiple magnet sections, for example a first magnet section adjacent the joint and a second magnet section or adjacent to the topped end. In some arms, a clamping finger can include multiple magnets spaced intervals along the clamping finger, from the connection end to the tipped end. In some cases, the tipped ends of the clamping fingers include a magnet section for locking or latching the tipped ends of the clamping fingers together in the closed position. In some claws, the clamping fingers include barbs along a length of the fingers to latch a fish to the claw. Some tipped ends are bladed or sharpened to impale or stab a fish, for example a fish with soft material. Some tipped ends are hooked to catch and retain flexible fish (e.g., tangled wires, cables, ropes, cloths). The clamping fingers 186 extend linearly along the axis 122 and terminate a the free, tipped end 192 in a tip 204. The tip 204 is pointed, however, some tips are rounded, hooked, flat, or lipped. In some cases, the clamping fingers are arced.

[0056] The elbow joint 188 includes a stop 208 (e.g., a lock, block, protrusion, abutment) which prevents the elbow joint 188 from flexing past a predetermined angle. In the claw 180, the predetermined angle is 180 degrees or 0 degrees relative to the axis 122 (e.g., parallel to the tool axis). In some cases, the stop permits limited outward flexing of the clamping finger, for example, 15, 30, 45, or 60 degrees relative to the tool axis. The angle at which the joint or stop prevents outward flexing may be adjustable. For example, the stop angle may be determined by a diameter of the casing to prevent the tipped end of the clamping fingers from engaging and/or sticking onto the wellbore casing. In some cases, the stop angle is determined so that the clamping fingers contact or scrape against the wellbore casing. Dragging the tipped end of the clamping fingers along the casing can scratch or scrape off scale deposited on the inner lining of the wellbore casing. In some cases, the stop angle of the joint is set so that the tipped ends of the clamping fingers run adjacent to the wellbore casing at a known distance to remove or scrape scale that extends into the casing and/or impedes the axial path of the tool as the tool moves downhole in the wellbore.

[0057] The joint 188 each arm 184 in the multiple arms 182 of the claw 180 is an elbow joint. The elbow joint 188 permits rotation along a plane. The plane of each elbow joint 188 intersects the tool axis 122. In this configuration, the clamping fingers 186 of the arms 182 hinge or rotate the tipped end 192 towards the tool axis 122 or away from the tool axis 122. In some cases, the joint is a simple hinge, a living hinge, a ball joint, or similar joint mechanism. In some cases, the connection end of the clamping fingers and the joints are releasably connected. In some cases, the clamping fingers of the fishing tool can be customized to anticipate or predict the type of fish or debris located in the wellbore casing.

[0058] The claw 180 also includes multiple linkages 210 controllable by movement of the sling hub 220 to move or rotation the joints. The linkages 210 are operable to move the claw from the open position to the closed position and from the closed position to the open position. Each linkage of the multiple linkages 210 extends from the hub body 220 to a corresponding arm of the arms 180 The linkages 210 include or are flexible metal slings, for example chain slings, wire rope slings, or cable slings. The linkages can be formed by or with stainless steel. In this configuration, the flexible slings can be replaced if torn or damaged during operations.

[0059] In the open position, the tipped ends 192 of the claw 180 are parallel with the tool axis 122 and parallel to the base 185. The finger diameter in the open position is dfl. The open finger diameter is about 0.5 inches to about 1 foot (e.g., 1 inch to about 6 inches or about 1.5 inches to about 4 inches). The computer sub-system 124 can prompt the claw 180 to transition from the open state to the closed state, for example, after determining, by the imaging sub-system, that at least a portion of a fish is arranged in the claw 180. The linkages 210 of the claw move and/or rotate the joints 188 to move the tipped ends 192 of the clamping fingers 186 towards the tool axis 122 (e.g., radially towards the tool axis).

[0060] In the closed position, the tipped ends of the fingers 186 define a finger diameter d.sub.f2. The finger diameter de in the open position (open finger diameter) is greater than the finger diameter d.sub.f2 in the closed position (closed finger diameter). In some cases, the open finger diameter d.sub.f1 is equal to the closed finger diameter de. In some cases, the tips of the clamping fingers unite or touch at the axis to form a point or nib and the closed diameter is the outer diameter of the point (or nib). In some instances, the tips of the tipped ends of the clamping fingers include mating surfaces to releasably engage at least one other arm in the multiple arms. For example, the tipped ends can include magnets, male/female connections, hooks-eye connectors, ball-and-socket connectors, or other locks to couple the tipped ends of the clamping fingers together to retain the fish in the claw during removal of the tool from the wellbore.

[0061] The clamping fingers 188 are fixed in the closed position and can return to the open position by manual redress at the surface. When a fish is caught inside the claw, the camera can view and confirm the engagement of the fish with the claw. In some cases, the closed position is not a fixed position, and the movable claw can move freely between the open and closed positions in a wellbore. The linkages 210 control the open or closed position of the movable claw 180. The linkages (and claw) are in the open position when the movable claw moves downhole (in a first direction) towards a fish. The linkages 210 move from the open position to the closed position when the sling hub 178 is triggered (e.g., moved or translated axially along the axis) by contact with a fish. The linkages 210 move uphole (in a second direction opposite the first direction) to move the clamping fingers 186 towards the axis 122 about the joint 188, arriving at a closed position (FIG. 4B).

[0062] In some cases, the linkages of the claw are also operable to move the claw from the open position to an expanded position and move the claw from the expanded position to the open position. In an expanded position, the tipped ends of the clamping fingers defining the finger diameter have a finger diameter de that is greater than de and de.

[0063] The sling hub 178 is also mounted to the face 154 of the main body 130 and centered on the axis 122. The sling hub 178 includes a hub body 220 and a surface 222. The surface 222 is oriented towards the second end 120 of the tool 102. The hub body 220 connects the surface 222 to the main body 130. In use, the surface is receive a mechanical force from the fish that moves the claws from an open position to a closed position.

[0064] The contact surface 222 and the clamping fingers 186 of the multiple arms 182 define a claw volume 232. The claw volume 232 extends from the contact surface 222 to the second end 120 of the tool 102. In the open position, the claw volume is accessible by a fish or a portion of a fish. In the closed position, the claw volume decreases to retain the fish or portion of the fish.

[0065] FIG. 5 is a bottom view of the fishing tool 102. The sling hub 178 also defines an aperture 224 extending through the sling hub body 220 and surface 222. The aperture is centered on the axis 122 so that the aperture 224 axially aligns with the hole 152 of the main body 130. In this configuration, the lens 174, the hole 152, and the aperture 224 axially align along the tool axis 122. The camera 172 is operable to image the downhole environment of the wellbore by zooming or imaging the view through the aligned hole 152 and aperture 224. In some cases, the transparent shell extends into the aperture to block fluid from entering the aperture, hole, and compartment.

[0066] The finger diameter d.sub.f is measured from an outer surface of a first finger 186a to an outer surface of a second finger 186b. The distance between the first finger 186a and the second finger 186b (e.g., the finger diameter d.sub.f) is about 1 inch to about 6 inches (e.g., about 1.5 inches to about 4 inches). Some fingers diameters can depend on the size of the wellbore and/or the size and type of the anticipated fish in the wellbore.

[0067] The outer surface 138 of the barrel 136 has a barrel diameter d.sub.b. The barrel diameter d.sub.b is about 1 inch to about 12 inches (e.g., about 1 inch to about 12 inches, about 1 inch to about 6 inches, or about 1.5 inches to about 4 inches). Some barrel diameters can depend on the size of the wellbore and/or the size and type of the anticipated fish in the wellbore

[0068] The finger diameter may be greater than, equal to or less than the barrel diameter d.sub.b. In some cases, the open finger position de and the closed finger position d.sub.f2 are both less than the barrel diameter d.sub.b.

[0069] The inner surface 164 of the cover 160 defines a cover diameter d.sub.c. The cover diameter is about 1 inch to about 24 inches (e.g., about 2 inches to about 15 inches, about 1.75 inches to about 12 inches, 2.5 inches to about 4.5 inches, or about 3 inches to about 8 inches).

[0070] The annular space 200 defined between the inner surface of the cover 160 and the outer surface 128 of the barrel 136 is the gap distance d.sub.gap. The gap distance d.sub.gap is about 1 inch to about 2 inches.

[0071] FIGS. 6A-D are cross-sectional front views of the debris retrieval system 100 deployed in the wellbore 114 with a fish 230. The fish 240 is a coiled wire without a fishing neck. The tool 102 is inserted into the wellbore casing 112 and conveyed downhole into the casing 112. To diagnose or determine the presence of a fish and/or the size and shape of the fish, the computer sub-system 124 prompts the imaging sub-system 170. The imaging sub-system can first attempt to take an image or may determine that the fluid in the wellbore casing is too opaque to imaging the downhole environment properly. In some cases, the imaging sub-system may determine that debris is blocking the transparent shell and/or camera and/or lends. To clear the downhole environment of debris and/or clean the protective cover, the computer sub-system 124 prompts the fluid source and fluid pump to convey clean, transparent fluid from the fluid source to the tool 102. The clean fluid flows through the fluid line 144 and the port conduits 146 and is discharged through the fluid ports 140. The discharged fluid stream moves radially until contacting the inner surface of the cover 160. The inner surface of the cover guides the clean fluid downhole towards the second end 120 of the tool 102. The clean fluid pushes debris downhole and dilutes the wellbore fluid. Additionally, the clean fluid contacts the protective shell 176 and removes any debris from the protective shell 176. The computer sub-system 124 may vary the pump rate based on the cleaning operation purpose (e.g., to clean the protective shell and/or to dilute the wellbore fluid and/or to move suspended debris downhole). The clean fluid is fresh water and can be added with additives (surfactant and solvent).

[0072] The computer sub-system 124 can prompt the imaging sub-system to recalibrate and/or retest the downhole environment. If the imaging sub-system determines that the downhole environment can be properly imaged, the camera 172 and lens 174 of the imaging sub-system 170 generate images or imaging signals of the downhole environment. The lens may magnify or zoom during the imaging process. The images are transmitted to a display at the surface for viewing by an operator. The display may be part of the computer sub-system or may be connected to a transceiver of the computer sub-system. The operator may provide inputs to the computer sub-system based at least partially on the images on the display. In some cases, an operator controls the computer sub-system to prompt a change in position, prompt movement of the claw, determine a fish type, and/or determine whether the fish is retained in the claw.

[0073] If the imaging sub-system, operator, and/or computing sub-system determine or confirm the presence of a fish within the wellbore casing 112, the computing subsystem and/or operator prompts the tool 102 to move further downhole and to maintain the open position. In some cases, the computing sub-system determines at least one dimension of the fish and determines whether the claw is able to grip and retain the fish. As the tool 102 moves downhole, the imaging sub-system continues to image the downhole environment and monitor the nearing fish. Additionally, the computer sub-system transmits the images to the display at the surface.

[0074] The fish, or a portion of the fish, enters the claw volume 232 as the tool 102 continues to move downhole. The magnet sections 194 of the claw 180 may attract the fish into the claw volume, towards the surface. The fish 240 moves further into the claw volume until contacting the surface 222. The surface 222 receives a mechanical (uphole) force which begins to move the claws towards the closed position. In some systems, the computer sub-system determines that a fish has contacted the contact surface and prompts the device to continue downhole to further press the fish to the contact surface to completely close and lock claw in the closed position. The claw may be unlocked at the surface or in the wellbore by a jolting force. The computer sub-system may also prompt the fluid pump to stop pumping clean fluid to the tool. The fish can latch onto the magnet sections of the arms of the claw if the fish is attracted to the magnetic force of the magnets. The claw volume 232 decreases as the claw 180 moves from the open position to the closed position. The tips 204 of the clamping fingers 186 may touch in the closed position or, if only a portion of the fish can be inserted into the claw volume 232, the fingers 186 arrive at the closed position to grips the portion of the fish. For example, the claw volume can receive fish necks of about 1.5 inches to about 4 inches connected to a larger object. The claw can grip the fish next in the closed position and drag the fish uphole by the fish neck.

[0075] In some systems, the tipped ends of the fingers each have a pressure sensor mounted on an inner face of the finger. The pressure sensor can transmit signals containing pressure data to the computer sub-system. The computer sub system can use the pressure data to determine the grip strength of the claw and identify if the fish slipped from the grip during removal uphole.

[0076] While a mechanical sling hub has been described, in some systems, the sling hub includes a debris sensor operably connected to the computer sub-system. The sensor may be a contact sensor, s proximity sling hub, an optical sling hub, a transducer, an ultrasound sling hub, or an acoustic sling hub. In some tools, the sling hub includes a sensor arrangement mounted on and/or in the hub body.

[0077] While the sling hub has been described as mounted to the main body, some sling hubs are not directly mounted to the main body.

[0078] While the debris sling hub has been described as a separate component to the claw, in some tools, the debris sling hub is part of the claw.

[0079] A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope. Accordingly, other embodiments are within the scope of the following claims.