A tool and method for fishery salvage

Abstract

The application relates to the technical field of oil and gas field downhole operation, and particularly discloses an introducing tool and method for fishing fallen fish. The tool comprises a swing assembly, a spiral winding assembly, a driving assembly and a flow guide assembly. The swing assembly is used for connecting a fishing barrel and providing rotary motion; the spiral winding assembly can be switched between a closed state and an unfolded state, and forms an involute spiral line structure when unfolded to expand the introducing range; the driving assembly drives a first wire bundle and a second wire bundle by using the rotation of a turbine ring, realizes unfolding and closing of the spiral winding assembly, and completes resetting in cooperation with an elastic body; and the flow guide assembly can be switched between a blocking state and an open state, ensures fluid driving efficiency, and facilitates the passage of fallen fish. The tool actively guides fallen fish into the fishing barrel through the superposition of spiral winding action and swing action, significantly improves the introducing success rate, adapts to complex well conditions and different types of fallen fish, effectively shortens the operation time, reduces the fishing cost, and improves the production capacity recovery efficiency of difficult wells.

Description

Technical Field

[0001] This invention relates to the field of downhole operations technology in oil and gas fields, specifically to an introduction tool and method for retrieving fallen fish. Background Technology

[0002] During oil and gas field development, "fish-like" phenomena frequently occur during downhole operations. These occur when downhole tools, tubing, or other work materials accidentally detach and sink to the bottom of the well due to malfunction, breakage, or operational errors. The presence of these fish-like objects not only hinders normal production operations but can also lead to well shutdowns, severely impacting the oilfield's production capacity and economic benefits. Therefore, timely and effective retrieval of these fish-like objects is crucial for restoring normal well production.

[0003] Currently, coiled tubing fishing technology is one of the main techniques for handling fish that have fallen into the well. The core of the fishing operation lies in accurately guiding the fish into the fishing tool, then mechanically locking it with the fishing mechanism, and finally pulling it out of the well. However, the success rate of the fishing operation largely depends on the performance of the guiding mechanism, especially its ability to effectively guide fish of different shapes, sizes, and postures into the fishing tool.

[0004] In existing technologies, the most common introduction mechanism is the inverted cone guide shoe. This type of guide shoe generates natural guiding force through the guide slope of the inverted cone to guide the fish. However, the inverted cone guide shoe has a significant technical drawback: its effective guiding area is limited to the direct projected area of ​​the inverted cone. Successful introduction is only possible when the fish is precisely within the projected area of ​​the inverted cone. This structural limitation causes the inverted cone guide shoe to perform poorly in complex well conditions, especially when the fish is close to the casing wall, below the casing transition point in a casing-transformation well, or when there is a significant difference in diameter between the fish and the casing. In these situations, traditional inverted cone guide shoes often fail to effectively guide the fish into the retrieval tool.

[0005] To improve the introduction effect, some improved solutions have emerged in the prior art. For example, Chinese patent application No. 201920664637.9 discloses a novel oilfield downhole operation guide shoe device, which improves the introduction success rate and anti-detachment effect by expanding the introduction area and adding friction pads. However, this technical solution still has limited effectiveness in introducing fish that are attached to the casing wall or have fallen into the casing, and cannot fundamentally solve the problem of limited introduction range. In addition, Chinese patent application No. 201120153827.8 discloses an oil well retrieval guide shoe with a window design on the side wall of the guide shoe. Although it can introduce fish that are attached to the casing wall to a certain extent, this solution requires rotating the entire retrieval string during the introduction process, which is cumbersome and complicated, increases the operation time and difficulty, and is not suitable for practical field application.

[0006] As oilfield development deepens, the number of complex and unproductive wells continues to increase. Coupled with declining single-well production and reduced capacity construction, restoring production in these complex wells has become a crucial measure to improve oilfield productivity. The cost of fish retrieval operations ranges from tens of thousands to millions of yuan. However, repeated operations or failures due to low success rates or inability to retrieve fish not only result in a huge waste of human and material resources but may also lead to permanent well shutdowns and significant economic losses. Summary of the Invention

[0007] The purpose of this invention is to provide an introduction tool and method for retrieving fallen fish, which can actively expand the introduction range, adapt to various complex well conditions and different types of fallen fish, significantly improve the introduction success rate, reduce the number and time of retrieval operations, reduce operating costs, and provide effective technical support for restoring production capacity in difficult and complex retrieval wells.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] An introduction tool for retrieving fallen fish, comprising:

[0010] The oscillating assembly includes a base ring for connection to a retrieval tube, an oscillating ring rotatably connected to the base ring, and a second elastic body disposed between the oscillating ring and the base ring for providing rotational restoring force.

[0011] A spiral winding assembly, installed on the oscillating ring, includes a fixed spiral segment fixed to the oscillating ring and a plurality of unfolding spiral segments sequentially hinged to one end of the fixed spiral segment. The unfolding spiral segments include a plurality of intermediate spiral segments and an end spiral segment, and each unfolding spiral segment is provided with a limiting structure. The spiral winding assembly can switch between a closed state and an unfolded state, forming a ring structure in the closed state and unfolding into a spiral shape in the unfolded state.

[0012] The drive assembly includes a turbine ring rotatably connected to the oscillating ring and having multiple turbine blades, a rotating block fixedly connected to the turbine ring, a first wire harness with one end connected to the rotating block and the other end passing through each of the intermediate helical segments and then connected to the terminal helical segment, a compression block rotatably connected to the oscillating ring, a second wire harness with one end connected to the compression block and the other end passing through each of the intermediate helical segments and then connected to the terminal helical segment, and a first elastic body installed on the oscillating ring and sleeved on the second wire harness with both ends abutting against the oscillating ring and the compression block respectively;

[0013] The spiral winding assembly guides the falling fish by superimposing its unfolding and closing motions with the rotational motion of the swinging assembly.

[0014] Furthermore: the perforations through which the first wire harness passes in each of the relay helical segments are located radially outside the virtual circumference formed by each hinge axis, and the perforations through which the second wire harness passes in each of the relay helical segments are located radially inside the virtual circumference formed by each hinge axis.

[0015] Furthermore, it also includes a flow guiding assembly, which includes a plurality of flow guiding plates hinged to the turbine ring; the flow guiding assembly can switch between a first attitude and a second attitude. In the first attitude, each of the flow guiding plates deflects inward to close and form a conical structure, blocking the central through hole of the turbine ring; in the second attitude, each of the flow guiding plates deflects outward to separate and open the central through hole of the turbine ring.

[0016] Furthermore: when the turbine ring rotates in the first rotation direction under the action of fluid, the first wiring harness pulls the spiral winding assembly to switch to the unfolded state, and at the same time, the second wiring harness pulls the extrusion block to compress the first elastic body; when the fluid action stops, the elastic force of the first elastic body pushes the extrusion block, and the second wiring harness pulls the spiral winding assembly to switch to the closed state.

[0017] Furthermore: when the spiral winding assembly is fully unwound, the continued rotation of the turbine ring drives the oscillating ring to rotate in the first rotation direction, compressing the second elastic body; when the fluid action stops, the elastic force of the second elastic body drives the oscillating ring to reset in the opposite direction of the first rotation direction.

[0018] The present invention also provides a method for introducing fish using the above-mentioned fish-catching tool, comprising the following steps:

[0019] S1: Install the introduction tool at the end of the retrieval tube and lower it above the fallen fish. Turn on the pump to allow fluid to pass through the turbine ring, drive the turbine ring to rotate, drive the spiral winding assembly to unfold, and drive the swing ring to rotate.

[0020] S2: Continue to lower the introduction tool so that the unfolded spiral winding assembly and the rotating swing assembly can wind and guide the falling fish until the falling fish contacts and pushes open the guide plate;

[0021] S3: After the fish falls and pushes open the guide plate, the fluid passes through the central through hole of the turbine ring, which reduces the fluid power driving the turbine ring to rotate. The spiral winding assembly automatically closes under the action of the first elastic body, and at the same time, the swing ring rotates in the opposite direction to reset under the action of the second elastic body. The fish enters the interior of the retrieval cylinder as it continues to be lowered.

[0022] Further: If a failure is introduced in step S2, the retrieval tube is raised, and steps S1 and S2 are repeated.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] I. This invention achieves active winding and guiding of fallen fish by superimposing the unfolding / closing motion of the spiral winding component with the rotational motion of the swinging component. Compared with the passive guidance method of traditional inverted cone-shaped guide shoes that rely solely on a limited projected area, the spiral winding structure of this invention can form a sweeping range much larger than the diameter of the retrieval tube in the unfolded state, and actively guides the fallen fish to the center position through the winding action, thereby significantly improving the success rate of fish introduction and effectively solving the problem of limited guidance area in existing technologies.

[0025] Second, the spiral winding structure of this invention has good adaptability and is particularly suitable for solving special situations that are difficult to handle with existing technologies, including fish falling onto the casing wall, fish falling below the casing-to-well transition point, and small-diameter fish falling inside large-diameter casing. Through the flexible unfolding and winding action of the spiral structure, fish falling in different positions and postures can be effectively captured, overcoming the shortcomings of existing technologies that have strict requirements on the position of the fish falling.

[0026] Third, this invention employs a hydraulic drive system, controlling the unfolding and closing of the spiral winding assembly, as well as the rotation and resetting of the swing assembly, solely through ground pump pressure. The entire introduction process eliminates the need to rotate the retrieval string, avoiding the cumbersome operational procedures of some existing technologies. The turbine ring directly converts fluid power into mechanical motion, and combined with the energy storage and release of the elastomer, it achieves automated control of the introduction action, greatly simplifying on-site operations and improving work efficiency.

[0027] Fourth, because this invention significantly improves the success rate of fish introduction, it can effectively reduce the number of repetitions of retrieval operations, shorten operation time, and thus greatly reduce retrieval operation costs. For difficult and complex shut-in wells, this invention can successfully solve the problem of fish falling into the well that traditional methods cannot handle, enabling wells that might have been permanently shut down to resume production, providing strong technical support for increasing oilfield production.

[0028] Fifth, the flow guiding component of this invention adopts a segmented structure design, which can flexibly switch between blocking and open postures, ensuring both the driving efficiency of the turbine ring and the smooth passage of the fish. The overall structural design is reasonable, the cooperation relationship between the components is clear, which facilitates on-site installation and maintenance, and improves the reliability and service life of the tool. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the closed overall structure of an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the first posture structure of the flow guiding component according to an embodiment of the present invention;

[0031] Figure 3This is a schematic diagram of the spiral winding assembly in its unfolded state according to an embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of the structure of the swing assembly in rotation according to an embodiment of the present invention;

[0033] Figure 5 This is a schematic diagram of the structure of the oscillating component during rotation according to another embodiment of the present invention. Figure 2 ;

[0034] Figure 6 This is a schematic diagram of the second attitude structure of a flow guiding component according to an embodiment of the present invention. Figure 1 ;

[0035] Figure 7 This is a schematic diagram of the second attitude structure of the flow guiding component according to another embodiment of the present invention. Figure 2 ;

[0036] Figure 8 This is a schematic diagram of the overall cross-sectional structure of the flow guiding component in the second posture according to an embodiment of the present invention;

[0037] Figure 9 This is a schematic cross-sectional view of the unfolded state of a spiral winding assembly according to an embodiment of the present invention. Figure 1 ;

[0038] Figure 10 This is a schematic cross-sectional view of the closed state of the spiral winding assembly according to another embodiment of the present invention. Figure 2 ;

[0039] Figure 11 This is a schematic cross-sectional view of the unfolded state of a spiral winding assembly according to an embodiment of the present invention. Figure 1 ;

[0040] Figure 12 This is a schematic cross-sectional view of the unfolded state of a spiral winding assembly according to another embodiment of the present invention. Figure 2 ;

[0041] In the picture:

[0042] 100, Oscillating assembly; 110, Oscillating ring; 120, Base ring; 130, Second elastic body; 200, Drive assembly; 210, Rotating block; 220, First wiring harness; 230, Extrusion block; 240, Second wiring harness; 250, First elastic body; 260, Turbine ring; 300, Helical winding assembly; 310, Fixed helical segment; 320, Unfolding helical segment; 321, Intermediate helical segment; 322, Terminal helical segment; 400, Flow guide assembly; 410, Flow guide plate. Detailed Implementation

[0043] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0045] The fish-catching tool provided by this invention mainly includes four parts: a swing component 100, a spiral winding component 300, a drive component 200, and a flow guiding component 400. These parts cooperate with each other to achieve the function of actively winding and guiding the fish that have fallen into the water.

[0046] The swing assembly 100, serving as the connecting component between the entire introduction tool and the retrieval tube, includes a base ring 120, a swing ring 110, and a second elastic body 130. The base ring 120 is threadedly installed at the lower end of the retrieval tube, allowing direct installation using the existing threaded interface of the guide shoe at the end of the retrieval tube without modification. The swing ring 110 is mounted on the base ring 120 via bearings or other rotatable connections, enabling free rotation relative to the base ring 120. A second elastic body 130, preferably a torsion spring, is positioned between the swing ring 110 and the base ring 120, with one end fixed to the base ring 120 and the other end fixed to the swing ring 110. When the oscillating ring 110 rotates in the first rotation direction (e.g., counterclockwise), the second elastic body 130 is twisted and stores elastic potential energy. When the external force is removed, the second elastic body 130 releases the stored energy, causing the oscillating ring 110 to rotate and reset in the opposite direction (clockwise) of the first rotation direction.

[0047] The spiral winding assembly 300 is the core structure for guiding the fish to fall. It is mounted on the oscillating ring 110 and moves with the oscillating ring 110. The spiral winding assembly 300 includes a fixed spiral segment 310 and multiple unfolding spiral segments 320. The fixed spiral segment 310 is fixedly mounted on the oscillating ring 110 by welding or bolting, serving as the foundation of the entire spiral winding assembly 300. The unfolding spiral segments 320 include multiple intermediate spiral segments 321 and one end spiral segment 322. These spiral segments are connected sequentially by hinges to form a foldable chain structure. Specifically, the first intermediate spiral segment 321 is hinged to one end of the fixed spiral segment 310, subsequent intermediate spiral segments 321 are hinged sequentially, and the end spiral segment 322 is hinged to the last intermediate spiral segment 321. A limit structure is provided at each hinge point to limit the maximum unfolding angle of each unfolding spiral segment 320, ensuring that the spiral winding assembly 300 presents a predetermined involute spiral shape when fully unfolded.

[0048] In the closed state, the fixed helical segment 310, each intermediate helical segment 321, and the terminal helical segment 322 fit together to form a ring structure. The inner diameter of this ring structure is slightly larger than the outer diameter of the retrieval tube, so it will not affect normal well-running operations. In the deployed state, the helical winding assembly 300 begins to unfold from the cross-section between the fixed helical segment 310 and the terminal helical segment 322. Each intermediate helical segment 321 and the terminal helical segment 322 swing outward around their respective hinge axes. When they reach the limit position, the entire helical winding assembly 300 presents an involute helical shape, and its sweeping range can reach 2-3 times the ring diameter in the closed state, greatly expanding the introduction range.

[0049] The drive assembly 200 is a power mechanism that controls the unfolding and closing of the helical winding assembly 300, and its design cleverly utilizes the hydrodynamics during downhole operations. The drive assembly 200 includes a turbine ring 260, a rotating block 210, a first wiring harness 220, a compression block 230, a second wiring harness 240, and a first elastic body 250. The turbine ring 260 is rotatably connected to the oscillating ring 110 via bearings, and its outer wall has multiple turbine blades evenly distributed. The angles of these turbine blades are optimized to generate maximum rotational torque when the working medium (such as drilling fluid) flows through them. The rotating block 210 is fixedly welded or bolted to the outer wall of the turbine ring 260 and rotates with the turbine ring 260.

[0050] The first wire harness 220 is made of high-strength steel wire rope or Kevlar fiber rope. One end is fixed to the rotating block 210 by a connector, and the other end passes through the pre-set holes on each intermediate spiral segment 321 in sequence, and finally connects to the end spiral segment 322. The positions of these holes are carefully designed, all located on the radial outer side of the virtual circumference formed by each hinge axis. This arrangement ensures that when the first wire harness 220 is pulled, an effective torque can be generated to make each unfolding spiral segment 320 swing outward.

[0051] The extrusion block 230 is also rotatably connected to the oscillating ring 110 via bearings or sliding pairs, and its position corresponds to that of the rotating block 210. The second wire harness 240 is made of the same material and has the same specifications as the first wire harness 220. One end of the second wire harness 240 is connected to the extrusion block 230, and the other end passes through the holes on each intermediate spiral segment 321 in sequence and connects to the end spiral segment 322. The holes through which the first wire harness 220 passes are located radially outside the virtual circumference formed by each hinge axis, and the holes through which the second wire harness 240 passes are located radially inside the virtual circumference formed by each hinge axis. This arrangement ensures that when the first wire harness 220 is pulled, it generates a torque that causes each unfolding spiral segment 320 to swing outward, driving the spiral winding assembly 300 to unfold; when the second wire harness 240 is pulled, it generates a torque that causes each unfolding spiral segment 320 to swing inward, driving the spiral winding assembly 300 to close. The first elastic body 250 is preferably a compression spring, which is sleeved on the second wire harness 240, with one end abutting against the fixed seat of the swing ring 110 and the other end abutting against the end face of the compression block 230. In the initial state, the first elastic body 250 is in a pre-compressed state, providing a certain pre-tightening force.

[0052] The design of the flow guiding assembly 400 fully considers the dual requirements of fluid guidance and fish passage. The flow guiding assembly 400 adopts a segmented structure, including multiple guide plates 410, typically 3-6 pieces, preferably 4 pieces. Each guide plate 410 is hinged to the inner edge of the turbine ring 260 and can rotate around the hinge axis. The guide plates 410 have a streamlined design to reduce fluid resistance. In the first orientation, each guide plate 410 deflects inward and closes under its own weight or spring force, with their edges fitting together to form a conical structure. The apex of this conical structure faces the bottom of the well, and the bottom blocks the central through-hole of the turbine ring 260. At this time, the high-pressure working medium pumped from the surface cannot directly pass through the central through-hole and is forced to flow through the turbine blades of the turbine ring 260, driving the turbine ring 260 to rotate. In the second posture, when the fish pushes the guide plate 410 from below, each guide plate 410 overcomes gravity or spring force and deflects outward to separate, fully opening the central through hole of the turbine ring 260, providing sufficient space for the fish to pass through.

[0053] The working principle of the tool introduced in this invention is as follows: When the turbine ring 260 rotates in the first rotation direction under the action of high-pressure fluid, the rotating block 210 fixed on the turbine ring 260 rotates accordingly, pulling the end helical segment 322 through the first wire harness 220. Since the perforations of the first wire harness 220 through each intermediate helical segment 321 are located radially outside the hinge shaft, the tension generates a torque that causes each helical segment to swing outward, thereby switching the helical winding assembly 300 from the closed state to the unfolded state. At the same time, as the end helical segment 322 is pulled, the second wire harness 240 is also tightened, thereby pulling the compression block 230 to move towards the end helical segment 322, compressing the first elastic body 250. When the spiral winding assembly 300 is fully unfolded, if the turbine ring 260 continues to rotate, since the unfolded spiral segment 320 has reached the limit position and cannot continue to unfold, the rotational force of the turbine ring 260 will be transmitted to the oscillating ring 110 through the drive assembly 200, causing the entire spiral winding assembly 300 to oscillate in the first rotation direction, while compressing the second elastic body 130.

[0054] When the pumping fluid stops, the turbine ring 260 loses its driving force. At this time, the compressed first elastic body 250 begins to release its stored elastic potential energy, pushing the compression block 230 to reset. This, through the second wiring harness 240, pulls the end spiral segment 322 and each intermediate spiral segment 321 to swing inward, causing the spiral winding assembly 300 to switch from the unfolded state back to the closed state. Simultaneously, the torn second elastic body 130 also releases energy, causing the swinging ring 110 to rotate and reset in the opposite direction of the first rotation direction. The closing motion of the spiral winding assembly 300 and the rotational reset motion of the swinging ring 110 are superimposed to form a spiral winding trajectory, which can effectively wind and guide fish in different positions to the center position.

[0055] In practical applications, the operation process is as follows: First, the introduction tool of this invention is installed at the end of the retrieval cylinder via a threaded connection, and then lowered into the well along with the coiled tubing. When the introduction tool is lowered to a position approximately 3-5 meters from the top of the fish, the surface pump station is started to pump the working medium. At this time, the guide assembly 400 is in its first position, the conical structure blocks the central through hole, and the high-pressure working medium is guided by the guide plate 410 to the turbine blades, driving the turbine ring 260 to rotate at high speed. The rotation of the turbine ring 260 causes the spiral winding assembly 300 to unfold through the aforementioned mechanism, and drives the oscillating ring 110 to rotate, preparing for the introduction of the fish.

[0056] In pumping mode, the introduction tool continues to be raised, and the fish is scanned and guided by the unfolding structure of the spiral winding assembly 300 and the rotational motion of the swing ring 110. After the fish is successfully guided to the center of the tool, the retrieval cylinder continues to be lowered, and the top of the fish will contact and push upward against the guide plate 410.

[0057] After the guide vane 410 is pushed open, the guide assembly 400 switches from the first blocked state to the second open state, and the central through hole of the turbine ring 260 is opened. At this time, the high-pressure working medium finds a path with less resistance, and most of the fluid will pass directly through the central through hole, thereby significantly reducing the amount of fluid and thrust acting on the turbine blades.

[0058] The turbine ring 260 thus loses its rotational power and stops or decelerates significantly. Subsequently, under the elastic force released by the compressed first elastic body 250, the compression block 230 is pushed, pulling the spiral winding assembly 300 to close rapidly and automatically via the second wiring harness 240; simultaneously, the torn second elastic body 130 also releases energy, causing the oscillating ring 110 to rotate in the opposite direction and reset. The superposition of the closing and rotational reset movements enables the final straightening and winding of the fallen fish.

[0059] The retrieval tube is then lowered further, allowing the fish to pass smoothly through the opened central through-hole and enter the tube, where it is locked in place by an internal locking mechanism. If the ground instruments do not detect the expected increase in load during lowering, it indicates a failed introduction. In this case, the operator simply needs to lift the retrieval tube; after the fish detaches, the guide plate 410 automatically resets and closes the central through-hole, allowing the fluid to drive the turbine to rotate again. This allows for repeated retrieval attempts without stopping the pump, greatly simplifying the operation and improving efficiency.

[0060] This invention is particularly suitable for handling fish retrieval operations under various complex well conditions. For example, for fish attached to the casing wall, traditional inverted cone guide shoes are often ineffective due to their limited effective guiding area. However, the spiral winding assembly 300 of this invention, in its unfolded state, can sweep close to the casing wall, peeling off the attached fish and guiding it to the center through a spiral winding action. For fish below the casing deformation point in wells with casing deformation, traditional guide shoes are even less effective due to the limited space caused by casing deformation. However, the spiral structure of this invention has good flexibility and adaptability, and can work effectively in deformed casing. For small-diameter fish in large-diameter casing, this invention, through its expanded sweeping range and active winding action, can accurately capture and guide small-sized fish, solving the problem of low guidance probability of traditional methods.

[0061] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent transformations or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A feeding tool for retrieving fallen fish, connected to a retrieval tube, characterized in that, include: The oscillating assembly includes a base ring for connection to a retrieval tube, an oscillating ring rotatably connected to the base ring, and a second elastic body disposed between the oscillating ring and the base ring for providing rotational restoring force. A spiral winding assembly, installed on the oscillating ring, includes a fixed spiral segment fixed to the oscillating ring and multiple unfolding spiral segments sequentially hinged to one end of the fixed spiral segment. The unfolding spiral segments include multiple intermediate spiral segments and an end spiral segment. Each intermediate spiral segment is provided with a through hole, and each unfolding spiral segment is provided with a limiting structure. The spiral winding assembly can switch between a closed state and an unfolded state. In the closed state, it forms a ring structure, and in the unfolded state, it unfolds into an involute spiral shape. The sweeping range in the unfolded state is larger than the diameter of the ring structure in the closed state. The drive assembly includes a turbine ring rotatably connected to the oscillating ring and having multiple turbine blades, a rotating block fixedly connected to the turbine ring, a first wire harness with one end connected to the rotating block and the other end passing through the holes of each of the intermediate helical segments and connected to the final helical segment, a compression block rotatably connected to the oscillating ring, a second wire harness with one end connected to the compression block and the other end passing through the holes of each of the intermediate helical segments and connected to the final helical segment, and a first elastic body installed on the oscillating ring and sleeved on the second wire harness, with both ends abutting against the oscillating ring and the compression block respectively; the holes through which the first wire harness passes in each of the intermediate helical segments are located radially outside the virtual circumference formed by each hinge shaft, and the holes through which the second wire harness passes in each of the intermediate helical segments are located radially inside the virtual circumference formed by each hinge shaft; When the turbine ring rotates in the first rotation direction under the action of fluid, the first wiring harness pulls the spiral winding assembly to switch to the unfolded state, while the second wiring harness pulls the extrusion block to compress the first elastic body. When the spiral winding assembly is fully unfolded, the continued rotation of the turbine ring drives the swing ring to rotate in the first rotation direction, compressing the second elastic body. When the fluid action stops, the elastic force of the first elastic body pushes the extrusion block, and the second wiring harness pulls the spiral winding assembly to switch to the closed state. At the same time, the elastic force of the second elastic body drives the swing ring to reset in the opposite direction of the first rotation direction. The closing motion of the spiral winding assembly and the rotational reset motion of the swing ring are superimposed to form a spiral winding trajectory, thereby achieving the winding guidance of the falling fish.

2. The introduction tool for retrieval of fallen fish according to claim 1, characterized in that, It also includes a flow guiding assembly, which includes multiple flow guiding plates hinged to the turbine ring, and the turbine ring has a central through hole. The flow guiding assembly can switch between a first attitude and a second attitude. In the first attitude, each flow guiding plate deflects inward to close and form a conical structure, blocking the central through hole of the turbine ring. In the second attitude, each flow guiding plate deflects outward to separate and open the central through hole of the turbine ring.

3. A method for introducing fish using the fish-catching tool described in claim 2, characterized in that, Includes the following steps: S1: Install the introduction tool at the end of the retrieval tube and lower it above the fallen fish. Turn on the pump to allow fluid to pass through the turbine ring, drive the turbine ring to rotate, drive the spiral winding assembly to unfold, and drive the swing ring to rotate. S2: Continue to lower the introduction tool so that the unfolded spiral winding assembly and the rotating swing assembly can wind and guide the falling fish until the falling fish contacts and pushes open the guide plate; S3: After the fish falls and pushes open the guide plate, the fluid passes through the central through hole of the turbine ring, which reduces the fluid power driving the turbine ring to rotate. The spiral winding assembly automatically closes under the action of the first elastic body, and at the same time, the swing ring rotates in the opposite direction to reset under the action of the second elastic body. The fish enters the interior of the retrieval cylinder as it continues to be lowered.

4. The method according to claim 3, characterized in that, If a failure occurs in step S2, raise the retrieval tube and repeat steps S1 and S2.

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