Well Connected Tube Fish Top Dresser

Abstract

The invention relates to the technical field of downhole operation, and discloses an in-well connected pipe fish top trimmer, comprising an upper connector and a reinforced guide shoe; a guide shoe connecting buckle is designed at the lower part of the upper connector, a reinforced guide shoe is arranged below the guide shoe connecting buckle, a hollow concave repair area is arranged between the reinforced guide shoe and the guide shoe connecting buckle, the upper connector is connected to the reinforced guide shoe, and after assembly, the upper connector, the guide shoe connecting buckle, the hollow concave repair area and the middle part of the reinforced guide shoe are designed with a through hole; the hollow concave repair area includes a trimming concave block, the lower surface of the trimming concave block is provided with a concave surface inclined to the center of a circle, and the trimming concave block is embedded with trimming crushed alloy; the through hole diameter of the trimming concave block is smaller than the through hole diameter of the reinforced guide shoe; the trimmer can bring torn and damaged fragments, strips, etc. out of the ground through entrainment, friction, etc., to ensure that the well is clean.

Description

Technical Field

[0001] The invention relates to the technical field of downhole operations, in particular to an in-well connected pipe fish top finisher. Background Art

[0002] The coiled tubing fish top trimmer is a tool specially used for downhole operations, mainly used to repair and tidy up the fish top before the coiled tubing is salvaged. Since the coiled tubing may get stuck due to various reasons (such as formation leakage, improper treatment measures, etc.) during downhole operations, or the fish top may be deformed due to strong pulling and pulling during the salvage process, making salvage more difficult. At this time, it is necessary to use the coiled tubing fish top trimmer to repair the fish top and restore it to a smooth state to facilitate subsequent salvage operations. In the horizontal well operation of 5in casing and 3000m deep, the CT110*2in coiled tubing was stuck due to formation leakage or improper treatment. When it was lifted up, the sediment accumulated into a sand bridge to block the annulus, resulting in loss of return at the wellhead; when it was descending, the sediment was pushed to the depth and accumulated to encounter resistance, and part of it squeezed through the gap and pushed to the upper annulus, eventually causing the drill to get stuck.

[0003] The existing technology has the following problems in operation: the coiled tubing salvage often adopts the top-down graded cutting method. Baosteel CT110 coiled tubing is often in a bent state during operation in the wellbore due to its high tensile strength (about 534KN) and torsional strength (about 6462.6N·m). The fish top is close to the casing wall, the coiled tubing has large elasticity, and strong pulling and pulling can easily cause deformation, and the fish top is irregular. In this state, it is difficult for the cutting tube to continue to effectively salvage, which increases the difficulty of operation; in the past, downhole repair tools were flat grinding and concave grinding, but due to the characteristics of the above-mentioned coiled tubing, ordinary grinding shoes could not be used for overall and full coverage repair, which could easily cause the fish top to split and the coiled tubing to spiral, which may cause secondary downhole accidents and increase the difficulty of salvage; when the debris in the pipe is large or the flow rate in the hollow area is insufficient, the water flow cannot generate enough drag to drive the debris, so the debris cannot be effectively brought out. Summary of the invention

[0004] (I) Technical problems to be solved: In view of the deficiencies of the prior art, the present invention provides a well-connected pipe fish top trimmer, which has the advantages of being able to bring torn and damaged fragments and strips out of the ground by entrainment, friction, etc., to ensure the cleanliness of the well; avoiding tearing of the fish top, and making the fish top smooth after repair, thereby solving the problems of the prior art that the fish top is prone to splitting, the connected pipe is swirling, the cutting tube is difficult to salvage continuously and effectively, and large fragments are prone to remain in the well.

[0005] (II) Technical solution: In order to achieve the above-mentioned purpose of bringing torn and damaged fragments and strips out of the ground by entrainment, friction, etc. to ensure the cleanliness of the well; avoiding tearing of the fish top and making the fish top smooth after repair, the present invention provides the following technical solution: an in-well connected pipe fish top trimmer, used together with a drill pipe and a drilling pump, suitable for trimming connected pipes made of magnetic metal materials, the trimmer includes an upper connector and a reinforced guide shoe; the upper connector includes an upper joint, a guide shoe connecting buckle, a hollow concave repair area, a water eye and a hollow area.

[0006] A guide shoe connecting buckle is designed at the lower part of the upper joint, a reinforced guide shoe is arranged below the guide shoe connecting buckle, a hollow concave repair area is arranged between the reinforced guide shoe and the guide shoe connecting buckle, the upper connecting piece is connected to the reinforced guide shoe, and after assembly, the upper joint, the guide shoe connecting buckle, the hollow concave repair area and the middle part of the reinforced guide shoe are designed with a through hole.

[0007] The hollow concave repair area includes a trimming block, the lower surface of which is provided with a concave surface inclined toward the center of a circle, and trimming crushed alloys of different sizes are embedded in the trimming block. The trimming block is fixedly connected to the outer surface of the guide shoe connecting buckle; the diameter of the through hole of the trimming block is smaller than the diameter of the through hole of the reinforced guide shoe.

[0008] Preferably, the through hole portion of the upper joint is designed with a water eye and a hollow area, and a magnetic clamp is arranged inside the water eye and the hollow area. The magnetic clamp includes a concave arc-shaped clamping plate, and the outer side of the clamping plate is connected to the inner wall of the through hole of the upper joint through a spring. Each group of the magnetic clamps is composed of more than two clamps that are matched to form a circular ring shape, and the inner hole of the circular ring formed by the clamping plates is coaxial with the through hole.

[0009] Preferably, the clamp has freedom of movement inside the water hole and the hollow area, and the clamp has magnetism; and entrained alloy fragments of different sizes and shapes are installed between the clamp and the inner wall of the water hole and the hollow area of ​​the upper joint.

[0010] Preferably, the concave surface inclination angle of the trimming concave block is between 30 degrees and 60 degrees.

[0011] Preferably, the upper joint and the guide shoe connecting buckle are processed as one piece, and the upper connecting piece and the reinforced guide shoe are connected by threads.

[0012] Preferably, the inner diameters of the water eye and the hollow area are smaller than the outer diameter of the repaired connecting pipe.

[0013] Preferably, the entrained alloy chips are made of non-magnetic material.

[0014] Preferably, the magnetic clamp is fixedly connected to the water eye and the inner wall of the hollow area, and the plurality of clamps are coaxially distributed; when the clamps are not attracted to the large fragment, there is no contact surface between the plurality of clamps.

[0015] Preferably, the upper connecting piece and the reinforced guide shoe are both streamlined, and the lower surface of the reinforced guide shoe is an inclined surface inclined toward the center of the reinforced guide shoe.

[0016] (III) Beneficial effects: Compared with the prior art, the present invention provides a well-connected pipe fish top trimmer, which has the following beneficial effects: 1. The well-connected pipe fish top trimmer adopts a hollow concave surface of 30 degrees to 60 degrees, and the inside and outside of the trimming concave block are densely covered with high-strength crushed alloy. The thread can be used to control the extension of the trimming alloy in the hollow concave repair area. The concave surface of the trimming concave block stabilizes the fish top on a repair surface, plays a role in smooth repair, avoids tearing the fish top, and uses the trimming crushed alloy to increase friction, so that the fish top reaches a flat state after repair. The hollow concave design can achieve full coverage repair of the fish top and avoid the problems of fish top splitting and tube circling that may be caused by the use of ordinary grinding shoes. In view of the problem of increased difficulty in salvaging due to fish top deformation during the continuous tubing salvage process, the dresser can effectively deal with the characteristics of Baosteel CT110 continuous tubing with high tensile and torsional strength, as well as the irregular fish top caused by the bending state of the continuous tubing in the wellbore in each length cycle. Compared with the flat grinding and concave grinding in the prior art, the dresser is more precise and effective.

[0017] 2. The well-connected fish top dresser sets magnetic clamps and carries broken alloys in the water eyes and hollow areas to carry large fragments and small debris produced by repair out of the well surface to avoid them remaining in the well and affecting operations. When the water flow carries debris into the water eye and hollow area, due to the change in the diameter of the central area, the water flow generates multiple vortices, which gather together to form a large vortex; inside the vortex, the lighter debris and the larger fragments will present different physical states due to their different masses and inertias; for the lighter debris, due to its small mass and small inertia, it is more easily affected by the change of water flow velocity in the vortex. In the vortex, the water flow velocity gradually increases from the center of the vortex to the outside, forming a velocity gradient, and the lighter debris will be more easily driven by the high-speed water flow on the periphery and make circular motion along the tangent direction of the vortex. These debris may continue to make complex trajectory motions on the periphery or inside the vortex as the vortex rotates, but generally tend to remain on the periphery or edge area of ​​the vortex, because the water flow velocity in these areas is greater and the impact force on the debris is also stronger. Therefore, the inner wall surface of the water eye and hollow area is designed with different sizes and shapes of densely distributed entrained alloy fragments, and the gaps between the entrained alloy fragments are used to entrain small debris The debris is carried out of the well surface; for the fragments with larger mass, due to their large mass and inertia, they are not easily driven by the rotational force of the vortex. After entering the vortex, these fragments may maintain their original state of motion due to inertia, or gradually move toward the center of the vortex due to the relatively large pressure in the low flow velocity area in the center of the vortex. In the center of the vortex, the water flow velocity is the smallest, but the pressure is relatively large, which helps to push the fragments with larger mass to the center of the vortex. In addition, if the vortex is strong enough, it may also form a The water flow vortex fixes the larger fragments in the center of the vortex, so we set up multiple magnetic clamps inside the water eye and hollow area. The magnetic clamps are composed of clamps and springs, and are fixed to the inner surface of the water eye and hollow area by the spring end. Therefore, the clamps have freedom of movement in all directions in the hollow area. When the large fragment is located in the center of the vortex, since the trimmed connecting pipe is made of magnetic material, there is magnetic attraction between the large fragment and the clamps. The clamps in all directions approach the large fragment in the center and capture and fix it, and then carry it out of the well surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a half-section schematic diagram of the overall structure of the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of the reinforced guide shoe of the present invention.

[0020] Figure 3 It is a schematic diagram of the upper connecting member structure of the present invention.

[0021] Figure 4 This is a schematic diagram of the magnetic clamp structure of the present invention without adsorbing a large fragment.

[0022] Figure 5 It is a schematic diagram of the internal cross-sectional structure of the water eye and the hollow area of ​​the present invention.

[0023] Figure 6 It is a schematic diagram of the magnetic clamp structure of the present invention adsorbing a large fragment.

[0024] In the figure: 1. Upper connecting piece; 11. Upper joint; 12. Guide shoe connecting buckle; 13. Hollow concave repair area; 131. Trimming concave block; 132. Trimming broken alloy; 14. Water eye and hollow area; 2. Strengthening guide shoe; 3. Magnetic clamp; 31. Clamp; 32. Spring; 4. Entrained broken alloy. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] See also Figure 1-3, the well connecting pipe fish top trimmer is used together with the drill pipe and the drilling pump, and is suitable for trimming the connecting pipe made of magnetic metal material, the trimmer includes an upper connecting piece 1 and a reinforced guide shoe 2; the upper connecting piece 1 includes an upper joint 11, a guide shoe connecting buckle 12, a hollow concave repair area 13, a water eye and a hollow area 14, a guide shoe connecting buckle 12 is designed at the lower part of the upper joint 11, a reinforced guide shoe 2 is arranged below the guide shoe connecting buckle 12, a hollow concave repair area 13 is arranged between the reinforced guide shoe 2 and the guide shoe connecting buckle 12, the upper connecting piece 1 is connected to the reinforced guide shoe 2, and the assembled upper joint 11, the guide shoe connecting buckle 12, the hollow concave repair area 13 and the middle part of the reinforced guide shoe 2 are designed with a through hole; the hollow concave repair area 13 includes a trimming concave block 131 inside, the lower surface of the trimming concave block 131 is provided with a concave surface inclined to the center of the circle, and the trimming concave block 131 is embedded There are repaired broken alloys 132 of different sizes, and the repaired concave block 131 is fixedly connected to the outer surface of the guide shoe connecting buckle 12 by welding; the diameter of the through hole of the repaired concave block 131 is smaller than the diameter of the through hole of the reinforced guide shoe 2; the conventional continuous oil pipe salvage method is generally a top-down graded cutting, wherein Baosteel CT110 continuous pipe has high tensile strength and torsional strength, the pipe body yield load is about 534KN, and the torsional yield strength is about 6462.6N·m. Due to the characteristics of factory delivery and continuous pipe operation, the continuous pipe in the wellbore is in a bent state in each length cycle, the fish top is close to the casing wall, the continuous pipe expansion rate is large, strong pulling and hard pulling cause the continuous pipe to deform and the fish top to be irregular, and the cutting tube cannot achieve the purpose of sustainable salvage. Therefore, the repaired broken alloy 132 is used in the present invention to increase friction, and the deformed fish top is fully wrapped to achieve repair, so as to avoid tearing of the fish top and make the fish top smooth.

[0027] See also Figure 1-6 A magnetic clamp 3 is arranged inside the water eye and the hollow area 14, and the number of the magnetic clamps 3 is not less than two. The magnetic clamp 3 is composed of a clamp plate 31 and a spring 32 of not less than one. One end of the spring 32 is connected to the outer surface of the clamp plate 31, and the other end is connected to the inner wall of the water eye and the hollow area 14. The clamp plate 31 has freedom of movement inside the water eye and the hollow area 14. The clamp plate 31 is magnetic and can absorb fish top debris made of magnetic material; the inner wall surface of the water eye and the hollow area 14 is designed with entrained broken alloy 4, the size and shape of the entrained broken alloy 4 are irregular, the entrained broken alloy 4 is densely distributed, and there is a gap in the middle, which can entrain small debris. The entrained broken alloy 4 is fixedly connected to the inner wall of the water eye and the hollow area 14 by welding. The entrained broken alloy 4 is made of non-magnetic material to avoid the clamp plate 31 and the entrained broken alloy 4 attracting each other and affecting the entrainment of debris.

[0028] When the device is used, the drill pipe is used to place the shaper downward to 5-10m above the top of the fish to be repaired, and then the drilling pump is started and operated to ensure that the water flow in the water eye and hollow area 14 inside the shaper is smooth. The shaper is continued to be controlled downward to make the fish top to be repaired enter and be restrained inside the reinforcing guide shoe 2, and then the pressure is continued to be applied to make the fish top to be repaired enter the hollow concave repair area 13. The hollow concave repair area 13 stabilizes the fish top to be repaired and makes it deform and smooth under the action of pressure to achieve repair. The repair process The fragments generated by the process are impacted by the water flow and move upward along the water eye and the hollow area 14. The smaller debris is entrained and fixed in the gap of the entrained broken alloy 4. The larger fragments are located in the center of the water vortex and are adsorbed by the clamping plate 31. The clamping plate 31 has freedom under the action of the spring 32. Multiple magnetic clamps 3 press and fix the large fragments in the center of the water eye and the hollow area 14. After the fish top is repaired, the shaper is moved out of the water under the action of the drill rod, and the large fragments and small debris are entrained out of the water.

[0029] See also Figure 2-3 The upper joint 11 and the guide shoe connecting buckle 12 are processed as one piece to ensure the stability of the equipment; the upper connector 1 and the reinforced guide shoe 2 are connected through the thread on the outer surface of the guide shoe connecting buckle 12. The thread specification of the outer surface of the guide shoe connecting buckle 12 is NC26LH, which ensures a firm connection between the tools. The thread is designed as a left-hand thread, which has advantages in salvage and repair operations because it allows the tool to be fed in reverse while rotating, which is very useful when dealing with stuck drills or when reverse operation is required.

[0030] See also Figure 1 and Figure 3 The inclination angle of the concave surface of the trimming concave block 131 is between 30 degrees and 60 degrees, and the optimal angle is 45 degrees, so that the force is stable. The concave surface of the trimming concave block 131 stabilizes the fish top on a repair surface, plays a role in smooth repair, avoids tearing the fish top, and makes the fish top smooth after repair.

[0031] See also Figure 1 The inner diameter of the water eye and the hollow area 14 is smaller than the outer diameter of the repaired connecting pipe to avoid the damaged fish top entering the hollow area and causing invalid repair.

[0032] See also Figure 1 The magnetic clamp 3 is fixedly connected to the water eye and the hollow area 14 by welding. The clamping plate 31 is arc-shaped. When it is close to large debris, the contact surface is increased, making its entrainment function more stable. Multiple clamping plates 31 are coaxially distributed to achieve circular clamping of large fragments; when the clamping plate 31 is not attracted to the large fragment, there is no contact surface between the multiple clamping plates 31, that is, when it is not attracted to the large fragment, the multiple clamping plates 31 will not stick to each other due to mutual attraction, which can be achieved by controlling the size of the clamping plate 31, the magnetic strength and the spacing between the magnetic clamps 3.

[0033] See also Figure 1-2 The upper connecting piece 1 and the reinforcing guide shoe 2 are both streamlined to reduce the resistance caused by the water flow. The lower surface of the reinforcing guide shoe 2 is an inclined surface inclined toward the center of the reinforcing guide shoe 2, so that when the bottom end of the reinforcing guide shoe 2 contacts the top of the fish to be repaired, the top of the fish can enter the interior of the reinforcing guide shoe 2 along the inclined surface.

[0034] Working principle: The well-connected fish top trimmer adopts a hollow concave surface of 30 degrees to 60 degrees, and densely distributes high-strength crushed alloy inside and outside the trimming concave block 131. The thread can be used to control the extension of the trimming crushed alloy 132 in the hollow concave repair area 13. The concave surface of the trimming concave block 131 stabilizes the fish top on a repair surface, plays a role in smooth repair, avoids tearing the fish top, and increases friction by using the trimming crushed alloy. After repair, the fish top achieves a smooth effect. The hollow concave design can achieve full coverage repair of the fish top, avoiding the use of ordinary grinding shoes. The problems that may be caused include fish top splitting, coiled tubing circling, etc.; in view of the problem of increased difficulty in salvaging due to fish top deformation during coiled tubing salvage, the dresser can effectively deal with the characteristics of Baosteel CT110 coiled tubing with high tensile and torsional strength, as well as the irregular fish top caused by the bending state of the coiled tubing in the wellbore in each length cycle; compared with the flat grinding and concave grinding in the prior art, the dresser is more precise and effective; at the same time, by setting a magnetic clamp 3 and entrained broken alloy 4 in the water eye and hollow area 14, the large fragments and small debris produced by the repair are entrained out of the well surface to avoid remaining in the well and affecting the operation.When the water flow carries debris into the water eye and the hollow area 14, due to the change in the diameter of the central area, the water flow generates multiple vortices, which gather together to form a large vortex; inside the vortex, the lighter debris and the larger fragments will present different physical states due to their different masses and inertias; the lighter debris is more easily affected by the change in the water flow velocity in the vortex due to its small mass and small inertia. In the vortex, the water flow velocity gradually increases from the center of the vortex to the outside, forming a velocity gradient, and the lighter debris The debris will be more easily driven by the high-speed water flow at the periphery and make circular motion along the tangential direction of the vortex. These debris may continuously make complex trajectory motions at the periphery or inside the vortex as the vortex rotates, but generally tend to remain at the periphery or edge area of ​​the vortex, because the water flow speed in these areas is greater and the impact force on the debris is also stronger. Therefore, the inner wall surface of the water eye and the hollow area 14 is designed with entrained alloy fragments 4 of different sizes and shapes and densely distributed, and the gaps between the entrained alloy fragments 4 are used to entrain small debris and bring them out. Well surface; for fragments with larger mass, due to their large mass and inertia, they are not easily driven by the rotational force of the vortex. After entering the vortex, these fragments may maintain their original state of motion due to inertia, or gradually move toward the center of the vortex due to the relatively large pressure in the low-velocity area in the center of the vortex. In the center of the vortex, the water flow speed is the smallest, but the pressure is relatively large, which helps to push the larger mass fragments to the center of the vortex. In addition, if the vortex is strong enough, a water vortex may be formed in the center of the vortex to push the larger mass fragments. The piece is fixed in the center of the vortex, so we set up multiple magnetic clamps 3 inside the water eye and hollow area 14. The magnetic clamp 3 is composed of a clamp 31 and a spring 32, and the end of the spring 32 is fixed to the inner surface of the water eye and hollow area 14. Therefore, the clamp 31 has freedom of movement in all directions in the hollow area. When the large fragment is located in the center of the vortex, since the trimmed connecting pipe is made of magnetic material, there is a magnetic attraction between the large fragment and the clamp 31, and the clamps 31 in all directions approach the large fragment in the center and capture and fix it, and then carry it out of the well surface.

[0035] In summary, the well connected tube fish top trimmer can bring torn and damaged fragments and strips out of the ground through entrainment and friction, so as to ensure the cleanliness of the well; avoid tearing the fish top and make the fish top smooth after repair.

[0036] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0037] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A well pipe fish top trimmer, used together with a drill pipe and a drilling pump, suitable for trimming a pipe made of a magnetic metal material, the trimmer comprising an upper connecting piece (1) and a reinforcing guide shoe (2); the upper connecting piece (1) comprises an upper joint (11), a guide shoe connecting buckle (12), and a hollow concave repairing area (13), characterized in that: The lower part of the upper joint (11) is provided with a guide shoe connection buckle (12), a reinforced guide shoe (2) is arranged below the guide shoe connection buckle (12), a hollow concave repair area (13) is arranged between the reinforced guide shoe (2) and the guide shoe connection buckle (12), the upper connector (1) is connected to the reinforced guide shoe (2), and after assembly, the middle parts of the upper joint (11), the guide shoe connection buckle (12), the hollow concave repair area (13) and the reinforced guide shoe (2) are provided with a through hole; the hollow concave repair area (13) includes a trimming concave block (131) inside, the lower surface of the trimming concave block (131) is provided with a concave surface inclined toward the center of a circle, and trimming crushed alloys (132) of different sizes are embedded in the trimming concave block (131), and the trimming concave block (131) is fixedly connected to the outer surface of the guide shoe connection buckle (12); the through hole of the trimming concave block (131) The diameter of the through hole is smaller than the diameter of the through hole of the reinforcing guide shoe (2); the trimmer also includes a water eye and a hollow area (14); the through hole portion of the upper joint (11) is designed with a water eye and a hollow area (14); a magnetic clamp (3) is arranged inside the water eye and the hollow area (14); the magnetic clamp (3) includes a concave arc-shaped clamp (31); the outer side of the clamp (31) is connected to the inner wall of the through hole of the upper joint (11) through a spring (32); each group of the magnetic clamp (3) is composed of more than two clamps (31) aligned to form a circular ring shape; the inner hole of the circular ring of the clamp (31) is coaxial with the through hole; the clamp (31) has freedom of movement inside the water eye and the hollow area (14); the clamp (31) has magnetism; and entrained broken alloys (4) of different sizes and shapes are installed between the clamp (31) and the inner wall of the water eye and the hollow area (14) of the upper joint (11).

2. The well-connected pipe fish top dresser according to claim 1, characterized in that: The concave surface inclination angle of the trimming concave block (131) is between 30 degrees and 60 degrees.

3. The well-connected pipe fish top dresser according to claim 1, characterized in that: The upper joint (11) and the guide shoe connecting buckle (12) are processed as one piece, and the upper connecting piece (1) and the reinforced guide shoe (2) are connected via threads.

4. The well connecting pipe fish top dresser according to any one of claims 1 to 3, characterized in that: The inner diameter of the water eye and the hollow area (14) is smaller than the outer diameter of the connecting pipe to be repaired.

5. The well connecting pipe fish top dresser according to any one of claims 1 to 3, characterized in that: The entrained alloy fragments (4) are made of non-magnetic material.

6. The well connecting pipe fish top dresser according to any one of claims 1 to 3, characterized in that: The magnetic clamp (3) is fixedly connected to the water hole and the inner wall of the hollow area (14), and the plurality of clamps (31) are coaxially distributed; when the clamps (31) are not attracted to the large fragment, there is no contact surface between the plurality of clamps (31).

7. The well connecting pipe fish top dresser according to any one of claims 1 to 3, characterized in that: The upper connecting piece (1) and the reinforced guide shoe (2) are both streamlined, and the lower surface of the reinforced guide shoe (2) is an inclined surface inclined toward the center of the reinforced guide shoe (2).

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