Subsea tree and tubing hanger mechanical retrieval tool

Abstract

The application discloses an underwater Christmas tree and tubing hanger mechanical recovery tool, which comprises a body, a blocking ring, a driving ring and a locking ring, and is characterized in that the tool further comprises a stop ring, a shearing ring and a piston; the stop ring is fixedly installed at the bottom of the internal axial channel of the body; the bottom right end of the shearing ring is extended downward to form a shearing part which is inserted into the top opening of the stop ring; the piston is internally provided with a plugging structure; the upper section of the piston is a sealing section, and the lower section is a shearing insertion section; two groups of sealing grooves are arranged between the upper side and the lower side of the height direction of the outer side of the sealing section of the piston, and the positions between the two groups of sealing grooves are communicated with an unlocking hydraulic channel through an emergency flow channel arranged in the body; the shearing insertion section of the piston can be pressed to cut off the shearing part of the shearing ring and then move downward, so that the unlocking hydraulic channel, the emergency flow channel and the internal axial channel of the body above the piston are communicated. The application has the advantage that the unlocking can be more reliable in an emergency.

Description

Technical Field

[0001] This invention belongs to the field of underwater oil pipe recovery technology, specifically relating to a mechanical recovery tool for underwater production tree oil pipes. Background Technology

[0002] In the process of oil and gas drilling and production using subsea production trees, a subsea wellhead is first constructed on the seabed. Then, a tubing hanger is installed at the head of the wellhead to suspend the tubing. Finally, the subsea vertical production tree is fixedly installed on the wellhead, and its operation is controlled and regulated to ensure smooth oil production. During this process, the tubing hanger is lowered and retrieved (or installed) using a delivery tool (or retrieval tool).

[0003] In the prior art, patent CN205669385U discloses an "emergency recovery tool for an oil pipe hanger," which includes a main body, a fixed ring, a drive ring, and a locking ring. A first protrusion is formed on the lower outer side of the main body. The first protrusion has a take-out section and a locking section with different diameters from top to bottom. The lower edge of the locking section forms a limiting protrusion along the radial outward. The fixed ring, drive ring, and locking ring are sequentially sleeved on the outer side of the main body from top to bottom. The lower end of the drive ring has a first cavity inside. The lower end of the side wall of the first cavity extends downward to form a pushing part. It also includes a compression spring that abuts against the fixed ring and the drive ring. The elastic force of the compression spring acts on the drive ring, causing the pushing part to push the locking ring to the locking section and abut against the limiting protrusion.

[0004] However, the aforementioned "emergency retrieval tool for tubing suspension" still has the following shortcomings:

[0005] When the hydraulic circuit of the drive ring on the main body fails, the drive ring cannot be driven, the locking ring cannot be unlocked, and the oil pipe hanger cannot be retrieved.

[0006] Based on this, the applicant is considering designing a mechanical recovery tool for underwater wellhead tubing that can better ensure reliable recovery of the tubing. Summary of the Invention

[0007] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is: how to provide a mechanical recovery tool for underwater production tree tubing hooks that can better ensure the reliable recovery of tubing hooks.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0009] A mechanical recovery tool for underwater wellhead tubing hooks includes a main body, and further includes, arranged sequentially from top to bottom on the outer side of the main body: a retaining ring fixedly mounted on the main body, a driving ring movably mounted on the main body, and a locking ring mounted on the main body. The locking ring can expand under the pushing action of the driving ring and insert into the corresponding annular slot of the tubing hook to form a lock.

[0010] A compression spring is provided between the retaining ring and the driving ring;

[0011] There is a stepped limiting surface between the inner side of the drive ring and the outer side of the body. On the outer side of the body, there are sealing grooves with annular seals at positions above and below the stepped limiting surface, so that an unlocking hydraulic cavity is formed between the stepped limiting surfaces. The body has an unlocking hydraulic channel communicating with the unlocking hydraulic cavity, and the top of the body has a hydraulic interface communicating with the unlocking hydraulic channel.

[0012] Its features are:

[0013] It also includes a stop ring, a shear ring, and a piston;

[0014] The stop ring is fixedly installed at the bottom position of the internal axial channel of the body;

[0015] The shear ring has an L-shaped cross-section, and the bottom right end of the L-shape extends downward to form a shearing part that is inserted into the top opening of the stop ring.

[0016] The piston has an internal sealing structure; the upper section of the piston is a sealing section, and the lower section is a shearing insertion section with an outer diameter smaller than that of the sealing section; two sets of sealing grooves equipped with O-rings are provided at intervals between the upper and lower sides of the outer surface of the sealing section of the piston in the height direction, and the position between the two sets of sealing grooves is connected to the unlocking hydraulic channel through an emergency flow channel provided inside the body; the lower end of the shearing insertion section of the piston overlaps with the shearing part of the shearing ring;

[0017] The piston's shearing insertion section can press and cut the shearing portion of the shearing ring and then move downwards, thereby connecting the unlocking hydraulic channel, the emergency flow channel, and the internal axial channel of the body located above the piston.

[0018] Compared with existing technologies, the underwater production tree tubing hoisting mechanical recovery tool of the present invention has the following advantages:

[0019] When the hydraulic circuit of the drive ring on the main body fails, the main body can be lowered by connecting the drill pipe on the platform to the threaded connection on the hoisting rod on the main body. Because the main body is equipped with a piston, shear ring and stop ring, liquid can be injected into the drill pipe from the offshore platform to provide hydraulic pressure to push the piston downward and shear the shear ring, and then continue to move downward. This will connect the unlocking hydraulic channel and the emergency flow channel with the internal axial channel of the main body located above the piston. The injected liquid can enter through the unlocking hydraulic channel and re-drive the drive ring on the main body to smoothly retract and unlock, achieving successful recovery.

[0020] As can be seen from the above, even if the hydraulic circuit of the drive ring fails, this technical solution can still make the drive ring retract and unlock in an emergency, further ensuring the reliability of tool recovery, more effectively guaranteeing the smooth progress of the operation, and reducing the huge time and financial losses caused by downtime due to failure. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the recovery tool of the present invention in a disengaged state;

[0022] Figure 2 This is a schematic diagram of the recovery tool of the present invention in the locked state;

[0023] Figure 3 for Figure 1 A magnified view of part A in the image;

[0024] Figure 4 for Figure 1 A magnified view of part B in the image;

[0025] Figure 5 for Figure 2 A magnified view of part C;

[0026] Figure 6 for Figure 2 A magnified view of a portion of the image.

[0027] Explanation of reference numerals in the attached figures

[0028] 1. Body (100 emergency flow channels, 101 annular protrusions)

[0029] 2 drive rings

[0030] 21 compression springs

[0031] 22 hydraulic channels

[0032] 221 Reset Step

[0033] 222 elevation steps

[0034] 3 locking rings

[0035] 31 Locking Hook

[0036] 32 flanges

[0037] 4 pistons (401 sealing section, 402 shearing insertion section, 403 sealing conical profile)

[0038] 5 steel balls

[0039] 6. Shear ring (601 shear section)

[0040] 7 retaining rings Detailed Implementation

[0041] The present invention will now be described in further detail with reference to the accompanying drawings.

[0042] In practical implementation: such as Figures 1 to 6 As shown, a mechanical recovery tool for underwater oil production tree tubing includes a body 1 and a locking mechanism installed on the body 1. The locking mechanism is used to lock the tree tubing onto the body 1 and to support the tree tubing.

[0043] During implementation, the main body 1 is cylindrical.

[0044] The locking mechanism includes a locking ring 3 and a driving ring 2, both of which are mounted on the body 1. The driving ring 2 is used to drive the locking ring 3 to change back and forth between the locked state and the disengaged state.

[0045] The locking state is that the locking ring 3 and the resin tube hanger are engaged and fixed together;

[0046] The disengaged state is when the locking ring 3 and the resin pipe are not engaged with each other and can move relative to each other.

[0047] In this way, the locking ring 3 can change the locking and disengaging state under the action of the driving ring 2. The driving structure is simple, and the locking ring 3 is ring-shaped, which can lock the tree oil pipe hanging 360 degrees, making it more stable and better in locking effect.

[0048] The drive ring 2 is sleeved and installed on the body 1 and can slide up and down along the body 1.

[0049] During implementation, a sliding groove is provided on the outer surface of the main body 1, and the drive ring 2 is installed on the main body 1 through the sliding groove and can slide along the sliding groove.

[0050] In this way, the drive ring 2 changes the state of the locking ring 3 by sliding, the execution process is simple, does not occupy any extra space (including the extension space of the robotic arm), and is highly adaptable.

[0051] A compression spring 21 is connected between the drive ring 2 and the body 1. The extension and retraction direction of the compression spring 21 is consistent with the sliding direction of the drive ring 2, and is used to push the locking ring 3 to the locking state through the drive ring 2.

[0052] In practice, the drive ring 2 has an upward-opening spring groove, and the compression spring 21 is located in the spring groove. One end of the compression spring 21 is connected to the protrusion on the top of the body 1, and the other end is connected to the bottom of the spring groove.

[0053] In this way, the locking state is maintained by the elastic force provided by the compression spring 21 itself, requiring no additional work, resulting in low consumption and low cost.

[0054] The main body 1 is provided with a hydraulic channel 22, which is connected to the drive ring 2 and is used to deliver hydraulic reset drive ring 2 so that the locking ring 3 is reset to the disengaged state.

[0055] During implementation, a reset step 221 is provided on the outer surface of the main body 1, and a lifting step 222 is provided on the inner surface of the drive ring 2 to cooperate with the reset step 221. A hydraulic reset chamber is formed between the reset step 221 and the lifting step 222. The hydraulic reset chamber is connected to the liquid inlet provided on the top of the main body 1 through the hydraulic channel 22.

[0056] In this way, hydraulic pressure can be delivered to the hydraulic reset chamber through the hydraulic channel 22. The hydraulic pressure can then be applied to the lifting stage 222 through the reset stage 221, causing the lifting stage 222 to overcome the elastic force of the compression spring 21 and drive the drive ring 2 to reset. The structure is simple and the reset action is efficient and stable.

[0057] The locking ring 3 is sleeved on the body 1 and abuts against the bottom of the drive ring 2. The locking ring 3 can slide up and down along the body 1.

[0058] During implementation, the locking ring 3 is positioned below the drive ring 2, and the locking ring 3 is moved up and down by the drive ring 2.

[0059] In this way, the state of the locking ring 3 can be changed by sliding it on the body 1. The state change process is simple, efficient, and highly adaptable.

[0060] The locking ring 3 is provided with a locking hook 31 extending radially outward, which is used to lock and support the tree oil pipe hanging.

[0061] In practice, the load-bearing hook is used both to lock the tree oil pipe hanging and to support the tree oil pipe hanging.

[0062] In this way, the locking hook 31 is a force-bearing element. When the locking ring 3 is recovering the tree oil pipe, it can lock and support the tree oil pipe through the locking hook 31. Moreover, the locking hook 31 extends radially outward, which can effectively improve the recovery of external loads with hooks.

[0063] When the locking ring 3 is in the disengaged state, the outer edge of the locking hook 31 does not extend beyond the outer surface of the drive ring 2.

[0064] During implementation, the radius of the drive ring 2 is smaller than the inner diameter of the tree oil pipe hook docking ring. In order to allow the locking hook 31 to enter and exit the hook position inside the tree oil pipe hook without obstruction, the outer edge of the locking hook 31 cannot exceed the outer surface of the drive ring 2 during the process of entering and exiting the tree oil pipe hook. At this time, the locking ring 3 is in a disengaged state, and there is no mutual engagement between the locking ring 3 and the tree oil pipe hook, and it can generate relative movement with the tree oil pipe hook.

[0065] In this way, the drive ring 2 and the locking ring 3 can smoothly and unobstructedly enter and exit the inner hole of the tree oil pipe hook in the disengaged state, without the locking hook 31 getting stuck with the tree oil pipe hook, which would prevent the recycling operation from being unable to proceed smoothly, and the recycling process is more stable.

[0066] The locking ring 3 is an expansion ring, and the outer surface of the body 1 is provided with a flange 32. The flange 32 is used to expand the locking hook 31 to extend beyond the outer surface of the drive ring 2.

[0067] In practice, the flange 32 is positioned in the direction in which the locking ring 3 changes from the disengaged state to the locked state. When the drive ring 2 pushes the locking ring 3 toward the flange 32, the locking ring 3 will expand outward under the action of the flange 32, thereby increasing the extension distance of the locking hook 31. When the extension of the locking hook 31 exceeds the outer surface of the drive ring 2, the locking ring 3 is in the locked state. At this time, the locking ring 3 can be fixed to the tree oil pipe hanger by connecting the docking ring on the tree oil pipe hanger.

[0068] In this way, the locking ring 3 can be changed to a locked state under the combined action of the driving ring 2 and the flange 32, so that the locking hook 31 entering the tree oil pipe docking ring can be engaged and fixed with the hook inside the tree oil pipe docking ring, thereby completing the locking operation. The locking action is simple and efficient, and the locking effect is better.

[0069] The locking surface of the locking hook 31 is a plane.

[0070] The locking surface of the locking hook 31 is also the bearing surface. The large surface area of ​​the plane results in small pressure and more stable bearing effect.

[0071] In use, the recovery tool is directly connected to the drill pipe with the universal guide frame. The drill pipe quickly lowers the recovery tool to the wellhead. After the recovery tool lands, drilling pressure is applied to the recovery tool through the drill pipe. After the hydraulic pressure is unloaded from the drive ring 2, the locking ring 3 on the recovery tool will quickly engage with the tree tubing docking ring and lock under the push of the compression spring 21. Then, the recovery tool is lifted up. The recovery tool pulls the tree tubing docking ring, allowing the tree tubing to be unlocked from the tree body 1. The tool is then lifted up until the tree tubing is recovered to the water surface.

[0072] During implementation, the main body 1 is provided with a hydraulic unloading channel that is connected to the hydraulic channel 22, and the hydraulic unloading channel is connected to the pressure relief port at the bottom of the main body 1.

[0073] The advantages of the above-mentioned underwater production tree tubing-mounted mechanical recovery tool are:

[0074] The locking mechanism eliminates the need for manual operation when retrieving the tubing hanger, avoiding risks to operators working underwater. It saves time and effort, and compared to ordinary hooks, the locking state is more stable, less prone to shaking, collision, or dragging, and has a better load-bearing capacity.

[0075] The aforementioned underwater production tree tubing hoisting mechanical recovery tool has the advantages of simple structure and easy implementation. It is suitable for installation and use on existing offshore platforms, and its operation and use costs are low, which can improve efficiency.

[0076] A mechanical recovery tool for underwater production tree tubing hangers includes a body 1, and further includes, arranged sequentially from top to bottom on the outer side of the body 1: a retaining ring fixedly mounted on the body 1, a driving ring 2 movably mounted on the body 1, and a locking ring 3 mounted on the body 1. The locking ring 3 can expand under the pushing action of the driving ring 2 and insert into the corresponding annular slot on the tubing hanger to form a lock.

[0077] A compression spring 21 is provided between the retaining ring and the driving ring 2;

[0078] The inner side of the drive ring 2 and the outer side of the body 1 have a stepped limiting surface. The outer side of the body 1 is provided with sealing grooves containing annular seals at positions above and below the stepped limiting surface, so that an unlocking hydraulic cavity is formed between the stepped limiting surfaces. The body 1 is provided with an unlocking hydraulic channel communicating with the unlocking hydraulic cavity, and the top of the body 1 is provided with a hydraulic interface communicating with the unlocking hydraulic channel.

[0079] It also includes a stop ring 7, a shear ring 6, and a piston 4;

[0080] The stop ring 7 is fixedly installed at the bottom position of the internal axial channel of the body 1;

[0081] The cross-section of the shear ring 6 is L-shaped, and the bottom right end of the L-shape extends downward to form a shearing part 601 that is inserted into the top opening of the stop ring 7.

[0082] The piston 4 has a sealing structure inside; the upper section of the piston 4 is a sealing section 401, and the lower section is a shearing insertion section 402 with an outer diameter smaller than that of the sealing section 401; two sets of sealing grooves equipped with O-rings are provided at intervals between the upper and lower sides of the outer surface of the sealing section 401 of the piston 4 in the height direction; the position between the two sets of sealing grooves is connected to the unlocking hydraulic channel through the emergency flow channel 100 provided inside the body 1; the lower end of the shearing insertion section 402 of the piston 4 overlaps with the shearing part 601 of the shearing ring 6;

[0083] The shearing insertion section 402 of the piston 4 can press and cut the shearing part 601 of the shearing ring 6 and then move downward, so that the unlocking hydraulic channel, the emergency flow channel 100 and the internal axial channel of the body 1 located above the piston 4 are connected.

[0084] The advantages of the above-mentioned underwater production tree tubing-mounted mechanical recovery tool are:

[0085] When the hydraulic circuit of the drive ring 2 on the main body fails, the main body can be lowered by connecting the drill rod on the platform to the threaded connection on the hoisting rod on the main body. Since the main body is equipped with a piston 4, a shear ring 6 and a stop ring 7, liquid can be injected into the drill rod from the offshore platform to provide hydraulic pressure to push the piston 4 downward and shear the shear ring 6, and then continue to move downward. This will connect the unlocking hydraulic channel, the emergency flow channel 100 and the internal axial channel of the main body 1 located above the piston 4. The injected liquid can enter through the unlocking hydraulic channel and re-drive the drive ring 2 on the main body to retract and unlock smoothly, thus achieving successful recovery.

[0086] As can be seen from the above, even if the hydraulic circuit of the drive ring 2 fails, this technical solution can still make the drive ring 2 retract and unlock in an emergency, further ensuring the reliability of tool recovery, more effectively guaranteeing the smooth progress of the operation, and reducing the huge time and financial losses caused by downtime due to failure.

[0087] In practice, it is preferable that each of the two sets of sealing grooves includes at least two sealing grooves fitted with annular seals. This will result in a better sealing effect.

[0088] During implementation, the retaining ring is fixedly connected to the internal thread at the bottom of the body via the external thread.

[0089] The internal axial channel of the body 1 has an annular protrusion 101 at the middle position in the height direction for limiting the piston 4, and the upper end of the piston 4 is in contact with the lower end face of the annular protrusion 101.

[0090] By using the aforementioned annular protrusion 101, the upper end face of the piston 4 can abut against the annular protrusion 101. That is, the piston 4 can be fixed and limited within the space inside the body 1 by the annular protrusion 101, the shear ring 6, and the stop ring 7, effectively preventing the piston 4 from accidentally shearing the shear ring 6 due to vibration or impact inside the body, ensuring the reliability of the structure and ensuring the correct realization of the function.

[0091] The piston 4 has a sealing structure inside, including a steel ball 5 and a sealing conical cylindrical surface 403;

[0092] The piston 4 is internally through, and the sealing section 401 of the piston 4 has a sealing conical cylindrical surface 403 that is larger at the top and smaller at the bottom at the middle position in the height direction.

[0093] The steel ball 5 is positioned and stopped on the sealing conical cylinder surface 403, forming a one-way seal from top to bottom.

[0094] The sealing structure inside the piston 4 described above has the advantages of simple structure, easy processing, and makes the piston 4 more economical in terms of material usage and lighter weight. At the same time, the piston 4 is pushed by pressure on the upper hemisphere of the sphere, which has a larger force-bearing area than the pressure-bearing plane, and can more efficiently push the piston 4 down to cut off the shear ring 6 and quickly realize the emergency unlocking function.

[0095] In addition, the steel ball 5 is used as a sealing component and a pusher in emergency situations, and it is also convenient to temporarily put the steel ball 5 down from the end of the drill rod on the platform in emergency situations. In this way, the main body, piston 4, shear ring 6 and stop ring 7 can be connected internally in non-emergency situations, which can facilitate the operation requirements when the connection is made and enrich the functions.

[0096] The lower surface of the entire horizontal side of the L-shaped cross-section of the shear ring 6 extends downward and thickens to form the shearing part 601. The radial outer side of the shearing part 601 is in close contact with the upper inner side of the stop ring 7.

[0097] In this way, the shear section 601 is thickened along the axial direction of the shear ring 6. The thickening makes the axial strength of the shear section 601 itself higher, thereby better ensuring the smooth force when the piston 4 pushes downward, and better ensuring the uniformity of stress shearing at the radial outer connection position of the radial upper surface of the shear section 601, thus avoiding the generation of chips.

[0098] The shear ring 6 is made of nylon material.

[0099] Nylon material has high structural strength, enabling it to reliably support the piston 4 without shearing. Nylon material also has a low coefficient of friction and some flame retardancy, preventing heat generation from friction and better ensuring safe unlocking in emergency situations.

[0100] During implementation, Nylon 1010 is the preferred nylon material, which has both thermal stability and low-temperature resistance (it can maintain structural stability even in low-temperature environments of -40 degrees Celsius), and the structure is reliable.

[0101] The vertical edge of the L-shaped structure of the shear ring 6 cross section thickens outward along its own radial direction.

[0102] In this way, after the shear ring 6 is cut, the vertical edge of the shear ring 6 will be pressed against the lower end of the sealing end of the piston 4. At this time, the vertical edge of the shear ring 6 forms a protective pad, preventing the piston 4 from directly hitting the stop ring 7, thus protecting the stop ring 7 and better ensuring the implementation of the emergency unlocking function.

[0103] The inner bottom of the stop ring 7 also has a conical surface with a gradually decreasing inner diameter, and the shortest distance between the lower end of the shearing part 601 and the upper end of the conical surface is less than the shortest distance between the piston 4 and the upper end surface of the stop ring 7.

[0104] During implementation, when the shearing portion 601 of the shearing ring 6 is cut off and moves down to the aforementioned conical surface under the continued pushing action of the piston 4, or before that, the connection between the hydraulic channel for unlocking, the emergency flow channel 100 and the internal axial channel of the body 1 located above the piston 4 is unlocked.

[0105] With the above structure, the conical surface can form a first-level blocking and limiting effect on the cut-off shearing part 601 and piston 4 (avoiding hard contact between piston 4 and stop ring 7).

[0106] The emergency flow channel 100 and the unlocking hydraulic channel both extend along the same radial direction of the main body 1.

[0107] This not only makes it easier to drill holes, but also minimizes the connection distance between the hydraulic chamber for unlocking and the emergency liquid delivery channel through the emergency flow channel 100, resulting in a faster response speed for emergency unlocking.

[0108] The above are merely preferred embodiments of the present invention. It should be noted that any modifications and improvements made by those skilled in the art without departing from the present technical solution should also be considered to fall within the scope of protection claimed in this claim.

Claims

1. An underwater Christmas tree and tubing hanger mechanical recovery tool, comprising a body, further comprising, from top to bottom, a blocking ring fixedly sleeved on the body, a driving ring movably sleeved on the body, and a locking ring sleeved on the body, the locking ring being capable of expanding and being inserted into a corresponding annular slot on the tubing hanger under the pushing of the driving ring to form locking. A compression spring is arranged between the blocking ring and the driving ring. A stepped limiting surface is arranged between the inner side of the driving ring and the outer side of the body, and a sealing groove containing an annular sealing member is arranged on the outer side of the body above and below the stepped limiting surface, so that an unlocking hydraulic cavity is formed between the stepped limiting surfaces; an unlocking hydraulic passage is arranged in the body and communicates with the unlocking hydraulic cavity, and a hydraulic interface is arranged on the top of the body and communicates with the unlocking hydraulic passage. Characterized in that: Further comprising a stop ring, a shear ring, and a piston. The stop ring is fixedly installed at the bottom of the axial passage in the body. The shear ring has an L-shaped cross section, and the bottom right end of the L-shaped structure extends downward to form a shear portion inserted into the top opening of the stop ring. The piston has a plugging structure; the upper segment of the piston is a sealing segment, and the lower segment is a shear insertion segment with an outer diameter smaller than that of the sealing segment; two groups of sealing grooves containing O-shaped sealing rings are arranged on the height direction of the outer side of the sealing segment, and the position between the two groups of sealing grooves communicates with the unlocking hydraulic passage through an emergency flow passage arranged in the body; the lower end of the shear insertion segment of the piston is lapped onto the shear portion of the shear ring. The shear insertion segment of the piston can be pressed to cut off the shear portion of the shear ring and then move downward, so that the unlocking hydraulic passage, the emergency flow passage, and the axial passage in the body above the piston are communicated. The shear ring is made of nylon material. The vertical edge of the L-shaped structure of the cross section of the shear ring is thickened radially outward.

2. The subsea tree and hanger mechanical retrieval tool of claim 1, wherein: The axial passage in the body has an annular protrusion for limiting the piston at the middle position in the height direction; the upper end of the piston is connected to the lower end surface of the annular protrusion.

3. The subsea tree and hanger mechanical retrieval tool of claim 1, wherein: The emergency flow passage and the unlocking hydraulic passage both pass through the same radial direction of the body.

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