CN114151036B - Multi-size fishing tool capable of radial tightening - Google Patents

Abstract

The invention relates to a multi-size fishing tool capable of radial tightening, which comprises an outer pipe and an inner pipe, wherein an outer fishing hook is fixed at the bottom end of the outer pipe, a through groove is formed in the lower pipe wall of the inner pipe, and an inner fishing hook capable of swinging along the radial direction of the inner pipe is pivoted in each through groove. An elastic tightening component is arranged in the inner pipe, and the part of each inner salvage hook below the pivoting position of the inner salvage hook is connected with the elastic tightening component. The inner tube is provided with a hydraulic pushing block in a sleeved mode above the elastic tightening assembly, pushing convex blocks are arranged on the outer sides of the hydraulic pushing blocks, and each pushing convex block can extend into each penetrating groove and can be abutted against each inner salvage hook. The multi-size fishing tool capable of being radially tightened can effectively grip the underground fish during fishing, and continuously provide gripping force in the lifting process, so that the situation that the underground fish falls down again in the lifting process is avoided; meanwhile, the underground fish with a certain size range can be salvaged, and the salvaging range is wider.

Description

Multi-size fishing tool capable of radial tightening

Technical Field

The invention relates to the technical field of underground salvage, in particular to a salvage tool with multiple sizes and radial tightening.

Background

According to the current situation of exploration and development, some areas which are buried deep and shallow, have good geological structures, few fracture development and the like and are easy to drill are basically brought into the end of development, the current main battlefield of drilling is transferred to areas with complex geological conditions, insufficient stratum awareness, complex bottom hole pressure and the like, the well is drilled deeper and deeper, the well track is also more and more complex, and the horizontal well gradually becomes the main stream. Drilling under the severe geological environment is extremely easy to induce underground accidents, such as necking and extruding drilling tools in the salt-paste layer drilling process; moreover, the friction torque of the deflecting section of some large-displacement wells is large, if the drilling tool is easily worn by the difficult-to-drill sandstone, the drilling tool is locally damaged, and the drilling tool is more easily broken under the severe environment of high temperature and high pressure; moreover, even if drilling has been completed, dropping of the measurement tool is extremely likely to occur during logging and other field tests at a later stage, creating a well fish.

However, the current common salvaging method in the field mainly comprises the steps of milling, wire making and then taking out, but the process is slower and the difficulty is higher; meanwhile, the mode can only be used for fishing the underground fish with a fixed shape and a fixed size, and the sleeve milling tool is easy to block when being put into the well, so that the fishing of the underground fish with a non-specific shape is difficult; in addition, for the instrument that can salvage soft fish such as cable, do not have locking device, take place very easily that the fish drops in the lifting process.

Therefore, the inventor has put forward a multi-size radial tightening fishing tool by virtue of experience and practice of related industries for many years, so as to overcome the defects of the prior art.

Disclosure of Invention

The invention aims to provide a multi-size fishing tool capable of radial tightening, which can effectively grip down-hole fish during fishing and continuously provide gripping force in the lifting process so as to avoid the situation that the down-hole fish falls down again in the lifting process; meanwhile, the underground fish with a certain size range can be salvaged, and the salvaging range is wider.

The invention aims to realize that the fishing tool with multiple sizes and radial tightening performance comprises an outer pipe and an inner pipe which is sleeved and fixed in the outer pipe at intervals; at least two outer salvage hooks are uniformly fixed at intervals along the circumferential direction of the bottom end of the outer pipe, at least two through grooves are uniformly arranged on the lower pipe wall of the inner pipe at intervals along the circumferential direction of the lower pipe wall of the inner pipe, and the through grooves extend downwards to the bottom of the inner pipe; the number of the through grooves is the same as that of the outer salvaging hooks, and each through groove is arranged opposite to the corresponding outer salvaging hook in the circumferential direction; an inner salvage hook capable of swinging along the radial direction of the inner pipe is pivoted in each through groove, the lower ends of the inner salvage hook and the outer salvage hook are respectively provided with a hook-shaped part, and the hook-shaped part of each inner salvage hook is arranged opposite to the corresponding hook-shaped part of the outer salvage hook; an elastic tightening component capable of enabling the lower part of each inner salvage hook to be folded towards the center is arranged in the inner pipe, and the part of each inner salvage hook below the pivoting position is connected with the elastic tightening component; the inner tube is provided with an elastic tightening component, and the elastic tightening component is arranged on the inner tube; the number of the pushing convex blocks is the same as that of the inner salvaging hooks, each pushing convex block can respectively extend into each through groove and can be propped against each inner salvaging hook, and the propping position is positioned below the pivoting position of each inner salvaging hook.

In a preferred embodiment of the invention, a locking rod is fixed in each through groove, two ends of the locking rod are fixed with two side groove walls of the through grooves, a through hole is formed in each inner salvage hook, and the through hole of each inner salvage hook is sleeved on the corresponding locking rod.

In a preferred embodiment of the present invention, the locking bar is a circular bar and the through hole is a circular hole.

In a preferred embodiment of the present invention, the elastic tightening assembly includes at least two springs and a central buckle, the number of the springs is the same as that of the inner salvage hooks, one end of each spring is fixedly connected with the corresponding inner salvage hook, the fixed position is located below the pivoting position of the inner salvage hook, and the other end of each spring is fixedly connected with the central buckle.

In a preferred embodiment of the present invention, the hydraulic pushing block comprises a solid cylinder, and the pushing blocks are uniformly fixed at intervals on the circumference of the side wall of the solid cylinder.

In a preferred embodiment of the invention, a sealing ring is fixedly sleeved on the top of the solid cylinder, and the outer diameter of the sealing ring is the same as the inner diameter of the inner pipe.

In a preferred embodiment of the invention, an inner rim is formed extending inwardly at the lower end of the inner tube, against which rim the sealing ring can rest.

In a preferred embodiment of the present invention, the outer wall of the solid cylinder is tapered with a downward cross section.

In a preferred embodiment of the present invention, the longitudinal section of the pushing bump along the axial direction of the inner tube is triangular.

In a preferred embodiment of the present invention, there are three outer salvaging hooks, three through slots, three inner salvaging hooks and three pushing bumps.

In a preferred embodiment of the present invention, an upper joint is fixedly connected to the upper end of the inner tube.

In the fishing tool with multiple sizes capable of being radially tightened, before the underground fish is not gripped, the inner fishing hooks can be radially tightened through the action of the elastic tightening assembly, so that a larger gap is reserved between the inner fishing hooks and the outer fishing hooks; after the underground fish enters the capturing range, the hydraulic pushing block is pushed downwards through pressing, so that the gap between the inner fishing hook and the outer fishing hook can be reduced, and the underground fish can be gripped.

Therefore, through the cooperation of outer fishing hook, interior fishing hook and hydraulic pressure impeller, under the condition that outer fishing hook grabs or hooks the down-hole fish, can provide a reverse propulsive force through interior fishing hook, tightly grab down-hole fish between outer fishing hook and interior fishing hook, perhaps only rely on the propulsive force effect of each interior fishing hook also can effectively grasp down-hole fish, and then realize the capture to down-hole fish, and constantly provide the grasping force in the grasping lifting process, prevent to lift up in-process in the fishing hook loosen, avoid catching the thing and drop once more, the reliability of salvaging has been guaranteed. Meanwhile, the fishing tool provided by the invention is not only used for fishing the underground fish with a certain size, but also can be used for fishing the underground fish with a certain size range, and is suitable for the fishes with various sizes, and the fishing range of the fishing tool is wider. The whole fishing tool is simple in structure, the capturing process can be controlled by controlling the pressure of drilling fluid, and the operation is simple and convenient.

Drawings

The following drawings are only for purposes of illustration and explanation of the present invention and are not intended to limit the scope of the invention.

Wherein:

fig. 1: the invention provides a structural schematic diagram of a multi-size fishing tool capable of radial tightening.

Fig. 2: the invention provides a top view of a multi-sized radially tightenable fishing tool.

Fig. 3: the outer pipe and the outer fishing hook are provided with a structural schematic diagram.

Fig. 4: the inner tube provided by the invention is schematically structured, and only one through groove is schematically shown in fig. 4.

Fig. 5: the invention provides a structural schematic diagram of an inner salvage hook.

Fig. 6: the invention provides a structural schematic diagram of an inner salvage hook in an initial position.

Fig. 7: the inner salvage hook provided by the invention is a schematic structural diagram after the outer salvage hook approaches under the thrust action of the hydraulic pushing block.

Fig. 8: the hydraulic pushing block provided by the invention is a structural schematic diagram, and only one pushing lug is shown in the figure 8.

Reference numerals illustrate:

1. An outer tube;

2. An inner tube; 21. a through groove; 22. a locking lever; 23. an inner edge;

3. An outer fishing hook;

4. An inner fishing hook; 41. a through hole;

5. An elastic gathering assembly; 51. a spring; 52. a central buckle;

6. a hydraulic pushing block; 61. a solid cylinder; 62. pushing the bump; 63. a seal ring;

7. And (5) an upper joint.

Detailed Description

For a clearer understanding of technical features, objects, and effects of the present invention, a specific embodiment of the present invention will be described with reference to the accompanying drawings.

As shown in fig. 1 to 8, the present embodiment provides a multi-sized radially-tightenable fishing tool, which includes an outer pipe 1 and an inner pipe 2 that is fixed in the outer pipe 1 in a spaced-apart manner.

At least two outer salvage hooks 3 are uniformly fixed at intervals along the circumferential direction at the bottom end of the outer tube 1, at least two through grooves 21 are uniformly arranged on the lower tube wall of the inner tube 2 at intervals along the circumferential direction, and the through grooves 21 extend downwards to the bottom of the inner tube 2. The number of the through grooves 21 is the same as that of the outer salvaging hooks 3, and each through groove 21 is arranged opposite to the corresponding outer salvaging hook 3 in the circumferential direction. An inner salvage hook 4 capable of swinging along the radial direction of the inner pipe 2 is pivoted in each through groove 21, the lower ends of the inner salvage hook 4 and the outer salvage hook 3 are respectively provided with a hook-shaped part, and the hook-shaped part of each inner salvage hook 4 is opposite to the hook-shaped part of the corresponding outer salvage hook 3.

An elastic tightening unit 5 capable of centering the lower portion of the inner bail 4 is provided in the inner tube 2, and a portion of each inner bail 4 located below the pivotal position thereof is connected to the elastic tightening unit 5. The inner tube 2 is sleeved with a hydraulic pushing block 6 above the elastic tightening assembly 5, at least two pushing convex blocks 62 which are circumferentially and uniformly distributed at intervals are arranged on the outer side of the hydraulic pushing block 6, and the vertical distance between the outer side end of each pushing convex block 62 and the axis of the inner tube 2 is larger than or equal to the inner radius of the inner tube 2 and smaller than the outer radius of the inner tube 2. The number of the pushing lugs 62 is the same as that of the inner salvaging hooks 4, and each pushing lug 62 can respectively extend into each through groove 21 and can be abutted against each inner salvaging hook 4, and the abutting position is located below the pivoting position of each inner salvaging hook 4.

Specifically, the outer salvage hook 3 and the inner salvage hook 4 are similar in structure, and each of the outer salvage hook 3 and the inner salvage hook 4 comprises an elongated plate body and a sharp hook formed at the bottom end of the elongated plate body, wherein the elongated plate body has a certain thickness so as to ensure salvage strength, and the sharp hook forms a hook part of each salvage hook. Generally, the top of the outer tube 1 is welded and fixed with the top of the inner tube 2, and the outer salvage hook 3 is welded at the lower end of the outer tube 1. The outer tube 1 and the inner tube 2 have the same axial length, the inner diameter of the outer tube 1 is larger than the outer diameter of the inner tube 2, and the interval between the two forms an annular space which can provide a movable space for the radial swing of the inner fishing hook 4. The number of the outer salvaging hooks 3, the through grooves 21, the inner salvaging hooks 4 and the pushing protrusions 62 is the same, for example, three are all arranged in this embodiment, and all are distributed at 120 ° intervals along the circumferential direction. Of course, other numbers may be provided as desired, and this embodiment is merely illustrative.

In order to facilitate the installation of the hydraulic pushing block 6 during the installation, after the outer tube 1 and the inner tube 2 are welded, the pushing convex blocks 62 of the hydraulic pushing block 6 are aligned with the positions of the through grooves 21 and pushed upwards from the bottom of the inner tube 2; then, each inner salvage hook 4 and the elastic tightening assembly 5 are installed, and each pushing bump 62 is guaranteed to be abutted against the inner salvage hook 4, and the abutting position is located below the pivot position of each inner salvage hook 4, so that the pivot of the pivot position is prevented from being damaged when the pushing bump 62 descends. The pivot of the pivot position is generally disposed near the outer side of the inner tube 2, and the thickness of the inner salvage hook 4 along the radial direction of the inner tube 2 is slightly smaller than the wall thickness of the inner tube 2, so as to ensure that the pushing projection 62 can abut against the inner salvage hook 4 below the pivot position.

In the initial position, the lower portion of each inner bail 4 is gathered toward the center by the elastic gathering member 5 to assume a gathered state, and in the position shown in fig. 6, the gap between the hook portion of the inner bail 4 and the outer bail 3 is large, and the large gap constitutes a catching range. When fishing an annular column-shaped underground fish, the side wall of the underground fish easily enters the capturing range. When the drilling tool is used, the upper end of the inner pipe 2 is fixed with the drill string, the drill string is used for carrying a fishing tool to be put into a well, and drilling fluid does not need to be injected into the pipe string in the process of putting into the well.

If the fishing down-hole fish is a ring-shaped column, when the fishing tool is lowered to a certain depth, the side wall of the down-hole fish will enter the gap between the inner fishing hook 4 and the outer fishing hook 3. At this time, drilling fluid is injected into the inner cavity of the pipe column, the hydraulic pushing block 6 is pushed to slowly move downwards by the pressure generated by the drilling fluid, and a pushing force is given to the inner fishing hook 4 in the moving process, so that the hook-shaped part of the inner fishing hook 4 gradually swings and approaches the outer fishing hook 3 outwards, the gap between the outer fishing hook 3 and the inner fishing hook 4 is gradually reduced, the position shown in fig. 7 is reached, and the underground fish is finally gripped.

The position of the inner fishing hook 4 after outward swinging swings outwards by a certain angle relative to the initial position, and the specific degree of outward swinging is determined by the size of the pushing projection 62 and the size of the fished down-hole fish, so that the inner fishing hook 4 after outward swinging can still be positioned at an inward gathering position, can be positioned at a vertical position and can also be positioned at a position slightly inclined outwards for opening, and the purpose of clamping the fish can be achieved. When the fishing tool is lifted up, the hydraulic pushing block 6 still can provide pushing force for the inner fishing hook 4 due to the gravity action of drilling fluid, so that the inner fishing hook 4 can continuously provide grasping force, and the falling phenomenon of the fish in the lifting up process is prevented.

For example, when the down-hole fish is a drill pipe with a joint, the joint outer diameter is generally larger than the drill pipe outer diameter, and a step is formed at the joint of the drill pipe and the joint, and the inner wall of the whole drill pipe is smooth. When salvaging, after this joint got into the capture scope, at least one outer fishing hook 3 can block the step, and each inner fishing hook 4 after pressing simultaneously can provide a props the power to the inner wall of joint, through the cooperation of outer fishing hook 3 and inner fishing hook 4, can effectively grasp this underground fish, realizes salvaging. If the inner wall of the underground fish also has steps, the inner salvaging hook 4 can be clamped on the steps of the inner wall during salvaging, and the grasping is more reliable. If the inner wall and the outer wall of the underground fish do not have steps, the supporting force of each inner fishing hook 4 is mainly utilized during fishing, and the fish can be smoothly gripped to realize fishing. For the underground fish in a certain size range, as long as the side wall of the underground fish can enter the capturing range, the underground fish can be gripped through the matching of the outer fishing hook 3 and the inner fishing hook 4 or the underground fish can be gripped only by the supporting force of the inner fishing hook 4, so that the fishing is realized, the fishing range is wider, and the underground fish is not limited to a fixed size.

If the salvaged underground fish is not in a regular fixed shape, such as a soft fish like a steel wire rope and a cable, the drilling fluid is not required to be added in the salvaging process, and only a salvaging tool is required to be placed underground to a certain depth, and the steel wire rope is hooked by the hook-shaped parts of the outer salvaging hook 3 and the inner salvaging hook 4. Of course, in order to salvage more reliably, can also press after wire rope gets into the capture scope for interior salvage hook 4 swing and be close to with outer salvage hook 3, play the effect of locking it when hooking wire rope, avoid lifting up the in-process wire rope and drop.

Thus, the multi-sized radially tightenable fishing tool of the present embodiment can radially tighten each inner fishing hook 4 by the action of the elastic tightening assembly 5 before lowering an unclamped down-hole fish, so that a large gap exists between the inner fishing hook 4 and the outer fishing hook 3; when the underground fish enters the capturing range, the hydraulic pushing block 6 is pushed downwards by pressing, so that the gap between the inner fishing hook 4 and the outer fishing hook 3 can be reduced, and the underground fish can be gripped.

Therefore, through the cooperation of outer fishing hook 3, interior fishing hook 4 and hydraulic pressure pushing block 6, under the circumstances that outer fishing hook 3 grabs or hooks the down-hole fish, can provide a reverse propulsive force through interior fishing hook 4, tightly grab down-hole fish between outer fishing hook 3 and interior fishing hook 4, perhaps only rely on the propulsive force effect of each interior fishing hook 4 also can effectively grasp down-hole fish, and then realize the capture to down-hole fish, and constantly provide the grasping force in the grasping lifting process, prevent that lifting in-process interior fishing hook 4 from loosening, avoid the catch to drop once more, the reliability of salvaging has been guaranteed. Meanwhile, the fishing tool in the embodiment is not only used for underground fish with a certain size, but also used for fishing the underground fish within a certain size range, and is applicable to the fishes with various sizes, and the fishing range of the fishing tool is wider. The whole fishing tool is simple in structure, the capturing process can be controlled by controlling the pressure of drilling fluid, and the operation is simple and convenient.

The fishing tool in this embodiment is mainly suitable for fishing annular column-shaped underground fish, or soft fish such as steel wire ropes and cables, and can be used for fishing small instruments similar to the annular column-shaped underground fish. Meanwhile, the fishing tool in the embodiment is not only suitable for fishing of a vertical well, but also suitable for fishing of a horizontal well.

In a specific implementation manner, in order to facilitate the swinging of the inner salvage hooks 4, as shown in fig. 1, 4 and 5, a locking rod 22 is fixed in each through slot 21, two ends of the locking rod 22 are fixed with two side slot walls of the through slot 21, a through hole 41 is formed in each inner salvage hook 4, and the through hole 41 of each inner salvage hook 4 is sleeved on the corresponding locking rod 22.

The locking lever 22 here is a straight lever and constitutes a pivot for the pivot point, around which locking lever 22 the inner fishing hook 4 can be swung through a certain angle. Generally, in order to ensure smooth swinging, the lock lever 22 is a circular lever, and the through hole 41 is a circular hole.

Further, in order to facilitate radial tightening of each inner salvage hook 4 in the initial position, as shown in fig. 1 and 2, the elastic tightening assembly 5 includes at least two springs 51 and a center button 52, the number of springs 51 is the same as that of the inner salvage hooks 4, one end of each spring 51 is fixedly connected with the corresponding inner salvage hook 4, and the fixed position is located below the pivoting position of the inner salvage hook 4, and the other end of each spring 51 is fixedly connected with the center button 52.

One end of the spring 51 is welded to the back of the inner fishing hook 4 (i.e., the side opposite to the tip hook), and the other end of the spring 51 is welded to the center button 52. The center button 52 may be a ring or a block. In this way, when the fishing operation is not performed on the underground fish, since the fixing point of the spring 51 and the inner fishing hook 4 is located below the pivot position, that is, below the locking lever 22, the lower portion of each inner fishing hook 4 is tightened toward the center under the tension of each spring 51, thereby increasing the gap between the lower portion of each inner fishing hook and the lower end of the outer fishing hook 3, and facilitating the subsequent fishing operation.

The function of the whole elastic tightening assembly 5 is mainly to tighten the inner fishing hook 4 in the initial position, ensuring a large clearance between the inner fishing hook and the outer fishing hook 3. As far as the spring 51 is concerned, if it breaks during the gripping of the fish by pressing after the fish has entered the capture zone, it does not affect the whole fishing process. Of course, other configurations of the elastic gathering assembly 5 are possible and the present embodiment is merely illustrative.

Further, for ease of processing and installation, as shown in fig. 8, the hydraulic pusher block 6 includes a solid cylinder 61, and each pusher lug 62 is fixed at uniform intervals in the circumferential direction of the side wall of the solid cylinder 61. When the underground fish enters the capturing range and is pressed, the whole hydraulic pushing block 6 descends under the hydraulic action of the drilling fluid, and each pushing lug 62 pushes the lower part of each inner fishing hook 4 to swing outwards, so that the gap between the inner fishing hook 4 and the outer fishing hook 3 is reduced to grasp or hook the underground fish.

In practical application, in order to ensure smooth pressing, a sealing ring 63 is fixedly sleeved on the top of the solid cylinder 61, and the outer diameter of the sealing ring 63 is the same as the inner diameter of the inner tube 2. The sealing ring 63 is preferably a rubber ring, so as to play a role in sealing and holding pressure when being pressed, so that the hydraulic pushing block 6 can smoothly move downwards.

Further, in order to limit the downward moving position of the hydraulic pushing block 6, the hydraulic pushing block 6 is prevented from going down too much when the drilling fluid pressure is too large, as shown in fig. 1 and 4, an inner edge 23 is formed by extending inward at the lower end of the inner tube 2, and the sealing ring 63 can be abutted against the inner edge 23. It will be appreciated that the inner edge 23 is also formed by a plurality of circular arc edges circumferentially spaced apart due to the presence of the through slot 21. During the process of installation, the hydraulic pushing block 6 can be installed inside the inner pipe 2, and after the inner salvage hook 4 and the elastic tightening assembly 5 are installed, the inner edge 23 can be welded and fixed.

In addition, the outer wall of the solid cylinder 61 is generally tapered with a downward cross section, which is more convenient for the hydraulic pushing block 6 to move downwards, and reduces the descending friction force. The pushing projection 62 is triangular along the axial longitudinal section of the inner tube 2, and the outer tip of the triangle is generally located at the middle upper part of the whole triangle, not at the bottom of the whole triangle, so that the outer tip of the triangle can be abutted against the inner salvage hook 4, and the inner salvage hook 4 can be pushed down more smoothly when being pressed. Of course, the hydraulic pushing block 6 may take other forms as desired, and this embodiment is merely illustrative.

Further, in order to facilitate connection with the drill string in use, an upper joint 7 is fixedly connected to the upper end of the inner pipe 2. The upper joint 7 is a tubular body and is provided with a male buckle, and can be matched with a female buckle on a drill string to fix the upper joint and the female buckle.

The foregoing is illustrative of the present invention and is not to be construed as limiting the scope of the invention. Any equivalent changes and modifications can be made by those skilled in the art without departing from the spirit and principles of this invention, and are intended to be within the scope of this invention.

Claims (9)

1. The multi-size radial tightening fishing tool is characterized by comprising an outer pipe and an inner pipe sleeved and fixed in the outer pipe at intervals;

at least two outer salvage hooks are uniformly fixed at intervals along the circumferential direction of the bottom end of the outer pipe, at least two through grooves are uniformly arranged on the lower pipe wall of the inner pipe at intervals along the circumferential direction of the lower pipe wall of the inner pipe, and the through grooves extend downwards to the bottom of the inner pipe; the number of the through grooves is the same as that of the outer salvage hooks, and each through groove is arranged opposite to the corresponding outer salvage hook in the circumferential direction; an inner fishing hook capable of swinging along the radial direction of the inner pipe is pivoted in each through groove, the lower ends of the inner fishing hook and the outer fishing hook are respectively provided with a hook-shaped part, and the hook-shaped part of each inner fishing hook is opposite to the corresponding hook-shaped part of the outer fishing hook;

An elastic tightening component capable of enabling the lower part of the inner salvage hook to be folded towards the center is arranged in the inner pipe, and the part of each inner salvage hook below the pivoting position of the inner salvage hook is connected with the elastic tightening component; the inner tube is internally sleeved with a hydraulic pushing block above the elastic tightening assembly, at least two pushing convex blocks which are circumferentially and uniformly distributed at intervals are arranged on the outer side of the hydraulic pushing block, and the vertical distance between the outer side end of each pushing convex block and the axis of the inner tube is larger than or equal to the inner radius of the inner tube and smaller than the outer radius of the inner tube; the number of the pushing convex blocks is the same as that of the inner salvaging hooks, each pushing convex block can respectively extend into each through groove and can be propped against each inner salvaging hook, and the propping position is positioned below the pivoting position of each inner salvaging hook; the hydraulic pushing block comprises a solid cylinder, and the pushing convex blocks are uniformly fixed on the circumference of the side wall of the solid cylinder at intervals; an upper joint is fixedly connected to the upper end of the inner tube.

2. A multi-sized radially collapsible fishing tool as defined in claim 1, wherein,

A locking rod is fixed in each through groove, two ends of the locking rod are fixed with two side groove walls of the through grooves, a through hole is formed in each inner salvage hook, and the through hole of each inner salvage hook is sleeved on the corresponding locking rod.

3. A multi-sized radially collapsible fishing tool as defined in claim 2, wherein,

The locking rod is a round rod, and the through hole is a round hole.

4. A multi-sized radially collapsible fishing tool as defined in claim 1, wherein,

The elastic tightening assembly comprises at least two springs and a central buckle, the number of the springs is the same as that of the inner salvage hooks, one end of each spring is fixedly connected with the corresponding inner salvage hook, the fixed position is located below the pivoting position of the inner salvage hook, and the other end of each spring is fixedly connected with the central buckle.

5. A multi-sized radially collapsible fishing tool as defined in claim 1, wherein,

The top of the solid cylinder is sleeved and fixed with a sealing ring, and the outer diameter of the sealing ring is the same as the inner diameter of the inner pipe.

6. A multi-sized radially collapsible fishing tool as defined in claim 5, wherein,

An inner rim is formed at the lower end of the inner tube and is inwardly extended, and the sealing ring can be abutted against the inner rim.

7. A multi-sized radially collapsible fishing tool as defined in claim 1, wherein,

The outer wall of the solid cylinder is a conical surface with a cross section tapered downwards.

8. A multi-sized radially collapsible fishing tool as defined in claim 1, wherein,

The pushing convex blocks are triangular in longitudinal section along the axial direction of the inner tube.

9. A multi-sized radially collapsible fishing tool as defined in claim 1, wherein,

Three outer salvaging hooks, three penetrating grooves, three inner salvaging hooks and three pushing convex blocks are arranged in total.