CN214118133U

CN214118133U - Fishing tool for corrosion eccentric wear well-falling sucker rod string

Info

Publication number: CN214118133U
Application number: CN202022954465.4U
Authority: CN
Inventors: 王照善; 李法军; 于昭东; 曹方起; 李淑芳; 邹远北
Original assignee: China Petroleum and Chemical Corp; Sinopec Shengli Oilfield Co Linpan Oil Production Plant
Current assignee: China Petroleum and Chemical Corp; Sinopec Shengli Oilfield Co Linpan Oil Production Plant
Priority date: 2020-12-11
Filing date: 2020-12-11
Publication date: 2021-09-03
Anticipated expiration: 2030-12-11

Abstract

The utility model discloses a fishing tool for a corrosion eccentric wear well sucker rod string, which comprises an upper joint and an outer cylinder, wherein the upper joint is sequentially in threaded connection with an upper body and the outer cylinder; the up end of toothholder is equipped with the toothholder spacing groove, is equipped with independent tooth piece in the inner chamber of toothholder, and independent tooth piece can reciprocate along the dovetail in the toothholder, and the butt joint of the spacing boss of toothholder of upper part of the body lower extreme and the toothholder spacing groove of toothholder is fixed between upper part of the body and urceolus. The utility model provides an independent tooth piece and independent push rod and independent spring cooperation accomplish the fishing work of the sucker rod post that corrodes the fracture of eccentric wear and fall the well. The fishing problem of the sucker rod string which is corroded, eccentrically worn, fractured and dropped into the well is effectively solved, the fishing task can be completed by one-time downhole, and the fishing tool has remarkable using effect and can produce remarkable economic and social benefits.

Description

Fishing tool for corrosion eccentric wear well-falling sucker rod string

Technical Field

The utility model relates to a fishing device of disconnected sucker rod that takes off in the oil industry tubular column in pit, especially corrode fishing tool of eccentric wear well sucker rod post.

Background

Along with the increase of water content in the later stage of oil field development, the corrosion aggravation and the wide use of lining oil pipes, the problem of well shut-in caused by the corrosion and the breakage of a sucker rod becomes more prominent, and along with the increase of small cased wells, "the sucker rod is broken and the sucker rod salvage" in the lining pipe and the small oil pipe with the shortened sucker rod salvage channel is the problem which needs to be researched and solved urgently in the aspect of controlling the lying well at present, and particularly the salvage at the obvious fracture part of the serious eccentric wear corrosion necking of a sucker rod string is the problem to be solved urgently.

In order to solve the problems, the following patent technologies are searched, but the problem of salvaging the broken sucker rod due to serious underground eccentric wear corrosion cannot be effectively solved.

An individual tooth block type utility model has the following application number: CN201120170922.9, patent name: the utility model relates to a high-performance sucker rod overshot, which comprises an upper joint, a cylinder body, a guide shoe, a slip, a sliding sleeve and a compression spring, wherein the outer part of the overshot comprises the upper joint, the cylinder body and the guide shoe which are sequentially connected into a cylinder with the same outer diameter and size from top to bottom through threads; the tapered hole wall at the lower end of the cylinder body is uniformly provided with a plurality of arc-shaped grooves which are inclined at the same angle, sliding slips are arranged in the arc-shaped grooves, the upper ends of a plurality of slips are all contacted with the bottom plane of a sliding sleeve pushed by a compression spring, the lower ends of the slips are all contacted with the middle step plane of a guide shoe connected with the cylinder body, and the slips can only reciprocate in the arc-shaped grooves without scattering. Although the tooth block of the fishing tool is split, the spring for pushing the tooth block to move is an integral spring, so the positions of the tooth block relative to the central axis are consistent, and the fishing tool cannot well adapt to the broken ends of the sucker rod with serious eccentric wear corrosion and different positions of the outer surface of the rod body in the radial direction and different distances from the central axis.

The utility model discloses a utility model patent technology of individual tooth piece formula, application number is: cn201320759316.x, patent name: "a multi-functional sucker rod fisher", the utility model discloses a: the upper end of the outer cylinder is in threaded connection with the upper connector, the lower end of the outer cylinder is in threaded connection with the guide shoe, and the upper end surface of the guide shoe is a guide conical surface; the upper section of the pressing sleeve is reduced to form a guide ring part, the lower section of the pressing sleeve is a ring sleeve part, the ring sleeve part is contacted with the inner side surface of the outer cylinder body, and the outer side of the guide ring part is sleeved with a compression spring; the upper ends of the limiting partition plates are contacted with the lower end of the ring sleeve part, and the lower ends of the limiting partition plates are connected with the upper end of the guide shoe; a plurality of movable joint portions are along circumference and each spacing baffle be setting in turn, including activity slider and card tooth piece, the lower terminal surface of activity slider is the outer inclined plane, its up end is the inclined plane, its interior wall is interior inclined plane, the up end of card tooth piece contacts with the lower terminal surface of ring cover portion, its lower terminal surface is including the outer inclined plane of second and the interior inclined plane of second, the outer inclined plane laminating of second is in the upper inclined plane, the inclined plane is the syntropy setting with interior inclined plane in the second, flush each other between the two, the internal face of card tooth piece is equipped with the card tooth. Although the tooth block of the fishing tool is split, the spring for pushing the tooth block to move is still an integral spring, so the positions of the tooth block relative to the central axis are consistent, the fishing tool cannot be well adapted to the broken ends of the sucker rods with serious eccentric wear corrosion and different distances from the central axis of the rod body at different radial positions, and the sliding block locking teeth are of a superposed structure, so that the unstable and unreliable use performance is easily caused.

An individual tooth block type utility model has the following application number: CN200420055129.4, patent name: "a minor diameter sucker rod fisher", the utility model discloses a: three inclined openings are uniformly distributed on the inner wall of the lower end of the upper joint in the axial direction, and moving steel balls are respectively arranged in the inclined openings. The minor diameter sucker rod fisher has the characteristics of small drift diameter, high bearing capacity, simple structure and high fishing efficiency. This utility model steel ball is placed alone and is not had spring drive, salvages to have unreliability.

Aiming at salvaging broken sucker rods due to serious underground eccentric wear corrosion, no reliable salvaging tool exists at present, and the salvaging tool for the underground eccentric wear corrosion broken sucker rods needs to be further improved.

Disclosure of Invention

The utility model aims at making the fishing tool who corrodes eccentric wear well sucker rod string that falls, accomplishing the salvage of the complicated rupture condition sucker rod string of corruption eccentric wear that falls the well, overcome the fishing difficult problem of the sucker rod string of the serious eccentric wear necking down of present sucker rod string corruption obvious fracture department in the pit. Improve and salvage efficiency, reduce and salvage the operating cost.

The technical solution of the utility model is that:

a kind of fishing tool which corrodes the sucker rod string of eccentric wear well, including top connection and outer cylinder, wherein:

the upper joint is sequentially in threaded connection with the upper body and the outer cylinder;

a push rod assembly hole is formed in the upper body, an independent spring and an independent push rod are arranged in the push rod assembly hole, and a tooth seat limiting boss is arranged at the lower end of the upper body;

the upper end surface of the tooth holder is provided with a tooth holder limiting groove, an independent tooth block is arranged in an inner cavity of the tooth holder, and the independent tooth block can move up and down along a dovetail groove in the tooth holder;

the tooth seat limiting boss at the lower end of the upper body is in butt joint with the tooth seat limiting groove of the tooth seat, and the tooth seat is fixed between the upper body and the outer barrel.

The inner cavity of the upper body is a non-equal-diameter inner cavity, the inner diameter of the upper inner cavity is larger than that of the lower inner cavity, internal threads are arranged in the upper inner cavity and connected with an upper connector, and a push rod assembly hole is arranged in the cavity wall of the lower inner cavity; the outer wall of the lower part of the upper body is provided with external threads which are connected with the threads on the upper part of the outer cylinder; the spacing boss of toothholder sets up at the lower terminal surface of the upper part of the body and sets up with the push rod pilot hole interval, and the medial surface of this spacing boss of toothholder is inclined plane down.

And a spring pad is also arranged between the table top between the upper inner cavity and the lower inner cavity of the upper body and the upper joint.

The inner cavity of the tooth holder is a conical inner cavity with a large upper part and a small lower part, the dovetail grooves are arranged in the inner cavity of the tooth holder, the arrangement number of the dovetail grooves is the same as that of the push rod assembly holes, and the arrangement positions of the dovetail grooves correspond to those of the push rod assembly holes.

The integral structure of the independent tooth block is a triangular block with a wide upper part and a narrow lower part, the lower inclined surface of the triangular block is an arc surface provided with tooth block clamping teeth, the two sides of the back surface of the lower inclined surface are provided with dovetails, and the tooth block clamping teeth are reverse upper inclined teeth; the independent tooth block is arranged in a dovetail groove in the inner cavity of the tooth base through a dovetail.

The outer barrel is a non-equal-diameter inner cavity, the upper inner cavity is provided with internal threads connected with the upper body, the lower inner cavity is a conical inner cavity with a small upper part and a large lower part, and the tooth holder is arranged on a table top formed between the upper inner cavity and the lower inner cavity.

the upper joint is in threaded connection with the outer cylinder;

the upper end surface of the tooth holder is provided with a tooth holder limiting groove, the inner cavity of the tooth holder is provided with tooth holder clamping teeth and is provided with an independent tooth block, and the independent tooth block can move up and down along a dovetail groove in the tooth holder;

the tooth seat limiting boss at the lower end of the upper body is butted with the tooth seat limiting groove of the tooth seat;

the positioning sleeve provided with the upper positioning rod is arranged on the upper body, and the lower part of the upper body fixing rod is inserted into the independent spring;

the positioning sleeve, the upper body and the tooth holder are all arranged in a space formed by the upper joint and the outer barrel, and the tooth holder is fixed through a lower positioning rod arranged in the outer barrel.

The center lines of the inner drift diameters of the positioning sleeve, the upper body, the tooth holder and the outer cylinder are offset on one side of the center line of the fishing tool; the upper positioning rod, the independent spring, the independent push rod, the independent tooth block and the lower positioning rod are all arranged on one axis and are positioned in the thick wall on one side of the inner drift diameter of the positioning sleeve, the upper body, the tooth seat and the outer barrel.

The inner cavity of the tooth holder consists of an offset center hole and a tapered hole, the tapered hole with a large upper part and a small lower part is positioned on one side of the dovetail groove, the straight hole is positioned on one side of the offset center hole, the inner wall of the straight hole is provided with tooth holder clamping teeth, the tapered hole is provided with the dovetail groove, and an independent tooth block is arranged in the tapered hole; the tooth holder clamping teeth are reverse upper oblique teeth which are the same as the tooth block clamping teeth, and tooth holder limiting grooves are uniformly distributed in the upper end surfaces of the tooth holders on the two sides of the dovetail groove; the lower end face of the tooth holder is provided with a lower positioning rod insertion hole.

The inner side surface of the tooth seat limiting boss opposite to the push rod assembling hole in the lower end surface of the upper body is provided with tooth seat clamping teeth; the lower positioning rod is arranged in a lower positioning rod mounting hole in the outer barrel, and the lower positioning rod mounting hole is a blind hole with the upper end communicated and the lower end plugged or a threaded hole with the upper end communicated and the lower end communicated.

The lower positioning rod mounting hole in the outer cylinder corresponds to the lower positioning rod insertion hole in the tooth holder, and the length of the lower positioning rod 41 is greater than the depth of the lower positioning rod mounting hole in the outer cylinder; the lower inner cavity of the outer cylinder is a conical cavity with a small upper part and a big lower part.

The fishing tool can have an outer diameter greater than 48mm or equal to 48mm or less than 48 mm.

Compared with the prior art, the utility model discloses can accomplish the corruption of falling the well and grind salvage of complicated rupture condition sucker rod string partially, have following excellent in use effect:

the utility model discloses there are two kinds of embodiments, all solve the salvage problem through the independent tooth piece that can follow the dovetail and independently remove. When the independent tooth blocks move up and down along the dovetail grooves in the tooth seats, one surface of the tooth blocks facing the central axis direction of the fishing tool is always parallel to the axis of the fishing tool, and different tooth blocks are driven by respective independent springs and independent push rods. When the sucker rod string is broken and falls into a well due to corrosion and eccentric wear, the independent tooth block corresponding to the eccentric wear position moves towards the eccentric wear surface of the sucker rod body under the driving of the independent spring and the independent push rod of the independent tooth block and is tightly meshed with the eccentric wear surface of the rod body through the tooth block clamping teeth parallel to the axial direction.

During salvaging, the salvaging tool is connected to the lower end of the salvaging rod column and is put into the well, when the salvaging tool reaches the upper part of the sucker rod body of the eccentric wear well, the salvaging tool continues to press the upper end part of the broken sucker rod and pushes the independent tooth block to move upwards and pass through the independent tooth block to enter the inside of the salvaging tool under the self gravity action of the salvaging rod column. At the moment, the fishing rod column and the fishing tool are lifted, the independent tooth block moves downwards along the dovetail groove and towards the central axis direction of the fishing tool under the action of the independent spring and the independent push rod at the upper part of the independent tooth block, and the independent tooth block installed in the tool tightly bites the eccentric sucker rod body from different directions. The fishing rod column is continuously lifted, and the fishing operation process can be smoothly completed.

The utility model provides an independent tooth piece and independent push rod and independent spring cooperation accomplish the fishing work of the sucker rod post that corrodes the fracture of eccentric wear and fall the well. The utility model discloses in the embodiment of offset formula that provides, because the assembly quantity of independent tooth piece, independent push rod and independent spring has been reduced, the external diameter can accomplish below 48mm, more can solve the salvage work of the sucker rod post of well falling among the little oil pipe.

The utility model discloses effectively solved the salvage problem of the sucker rod post that corrodes the eccentric wear fracture well that falls, just once go into the well and can accomplish the salvage task, have apparent result of use and can produce apparent economic benefits and social.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a first embodiment of the present invention.

Figure 2 is a schematic view of the dental socket of figure 1.

Fig. 3 is a schematic view of the structure of the individual dental block of fig. 1 and 5.

Fig. 4 is a schematic structural view of the upper body of fig. 1.

Fig. 5 is a schematic structural view of a second embodiment of the present invention.

Figure 6 is a schematic view of the dental socket of figure 5.

Fig. 7 is a schematic structural view of the upper body of fig. 5.

Detailed Description

The drawings are for reference and illustration purposes only and are not intended to limit the scope of the present disclosure. The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. Further, in the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

The utility model has two implementation modes

Implementation mode one

Referring to fig. 1, 2, 3 and 4, a fishing tool for eroding a partially worn down-hole sucker rod string comprises an upper coupling 31 and an outer barrel 38, wherein:

the upper joint 31 is sequentially in threaded connection with the upper body 32 and the outer cylinder 38;

a push rod assembly hole 322 is formed in the upper body 32, an independent spring 34 and an independent push rod 35 are arranged in the push rod assembly hole 322, and a tooth seat limiting boss 321 is arranged at the lower end of the upper body 32;

the upper end surface of the tooth holder 37 is provided with a tooth holder limiting groove 372, an independent tooth block 36 is arranged in the inner cavity of the tooth holder 37, and the independent tooth block 36 can move up and down along a dovetail groove 371 in the tooth holder 37;

the tooth socket limiting boss 321 at the lower end of the upper body 32 is butted with the tooth socket limiting groove 372 of the tooth socket 37, and the tooth socket 37 is fixed between the upper body 32 and the outer cylinder 38.

The utility model fixes the tooth socket 37 in the outer cylinder 38 from the axial direction and the circumferential direction. The utility model discloses a can solve because of the fishing problem of the sucker rod post that eccentric wear and corrosion fracture fell into the well along the independent tooth piece 36 that dovetail 371 independently removed, when independent tooth piece 36 reciprocated along dovetail 371 in the toothholder 37, independent tooth piece 36 was parallel with fishing tool's the central axis all the time towards fishing tool axis direction's one side, and different independent tooth piece 36 is driven by its respective independent spring 34 and independent push rod 35. When the sucker rod body at the fracture position in the sucker rod string is broken and falls into a well due to corrosion and eccentric wear, the independent tooth block 36 corresponding to the eccentric wear position of the sucker rod moves towards the eccentric wear surface of the sucker rod body under the driving of the independent spring 34 and the independent push rod 35 and is parallel to the eccentric wear surface of the sucker rod body tightly occluded by the independent tooth block 36 in the central axis direction, so that the sucker rod body can be smoothly salvaged to the ground.

On the basis of the first embodiment, the first embodiment further includes the following embodiments:

the inner cavity of the upper body 32 is a non-equal-diameter inner cavity, the inner diameter of the upper inner cavity is larger than that of the lower inner cavity, internal threads are arranged in the upper inner cavity and connected with the upper connector 31, and a push rod assembly hole 322 is arranged in the cavity wall of the lower inner cavity; the outer wall of the lower part of the upper body 32 is provided with external threads which are connected with the threads on the upper part of the outer cylinder 38; the limit boss 321 of the tooth holder is arranged on the lower end face of the upper body 32 and is arranged at an interval with the push rod assembly hole 322, and the inner side face of the limit boss 321 of the tooth holder is a lower inclined face. The tooth holder limiting boss 321 and the push rod assembly hole 322 are arranged at intervals, so that the installation of the independent spring 34 and the independent push rod 35 and the fixation of the tooth holder 37 are not interfered with each other, and the inner side surface of the tooth holder limiting boss 321 is a lower inclined surface which has a leading-in effect on a sucker rod string falling into a well.

A spring pad 33 is also arranged between the table top between the upper inner cavity and the lower inner cavity of the upper body 32 and the upper joint 31, which is convenient for assembling the independent spring 34.

The inner cavity of the tooth holder 37 is a tapered inner cavity with a large top and a small bottom, dovetail grooves 371 are arranged in the inner cavity of the tooth holder 37, the number of the dovetail grooves 371 is the same as that of the push rod assembly holes 322, and the arrangement positions correspond to those of the push rod assembly holes 322.

The integral structure of the independent tooth block 36 is a triangular block with a wide upper part and a narrow lower part, the lower inclined surface of the triangular block is an arc surface provided with tooth block clamping teeth 361, two sides of the back surface of the lower inclined surface are provided with dovetails 362, and the tooth block clamping teeth 361 are reverse upper inclined teeth; the individual blocks 36 are mounted in dovetail grooves 371 in the cavity of the block 37 via dovetails 362. After a sucker rod string which is broken due to corrosion and falls into a well is introduced into the tooth socket 37, the sucker rod string can go up along the tooth block clamping teeth 361 and pass through the tooth block clamping teeth 361 to enter the inner cavity of the upper body 32 under the pressing action of the self weight of the fishing rod string; when the fishing rod string is lifted, the tooth block clamping tooth 361 is a reverse upward inclined tooth, so that the tooth block clamping tooth can be tightly clamped outside the rod string, and the rod string is more tightly clamped due to the fact that the rod block clamping tooth 361 is downward.

The outer cylinder 38 is a non-equal diameter inner cavity, the upper inner cavity is provided with internal threads connected with the upper body 32, the lower inner cavity is a tapered inner cavity with a small upper part and a large lower part, the tooth holder 37 is arranged on a table top formed between the upper inner cavity and the lower inner cavity, and the lower inner cavity of the outer cylinder 38 has a guiding effect on a sucker rod string.

Use the utility model provides an above-mentioned embodiment is to when the salvage of the sucker rod post that falls into well because of corroding the eccentric wear fracture, connects this fishing tool at the fishing rod post lower extreme, along with in the fishing rod post goes into the well down.

When the fishing tool reaches the upper part of the rod body of the well-falling sucker rod, the fishing tool continues to press the upper end part of the broken sucker rod and pushes the independent tooth block 36 to move upwards under the action of the self gravity of the fishing rod column, the independent tooth block 36 moves upwards and outwards along the dovetail groove 371 in the conical inner cavity of the tooth seat 37, so that the inner channel of the fishing tool is expanded, and the broken sucker rod passes through the independent tooth block 36 and enters the upper body 32.

At this time, the fishing rod column and the fishing tool are lifted, the independent tooth blocks 36 move downwards along the respective dovetail grooves 371 and towards the direction of the eccentric wear surface of the broken sucker rod under the pushing of the respective independent springs 34 and the independent push rods 35, and the plurality of independent tooth blocks 36 tightly bite the eccentric wear broken sucker rod body from different directions; the salvaging operation process of the corrosion eccentric wear broken well-falling sucker rod string can be smoothly completed by continuously lifting the salvaging sucker rod string.

Second embodiment

Referring to fig. 5, 3, 6 and 7, a fishing tool for eroding an eccentrically worn sucker rod string comprises an upper coupling 31 and an outer barrel 38, wherein:

the upper joint 31 is in threaded connection with the outer cylinder 38;

the upper end surface of the tooth holder 37 is provided with a tooth holder limiting groove 372, a tooth holder clamping tooth 373 and an independent tooth block 36 are arranged in the inner cavity of the tooth holder 37, and the independent tooth block 36 can move up and down along a dovetail groove 371 in the tooth holder 37;

the tooth socket limiting boss 321 at the lower end of the upper body 32 is butted with the tooth socket limiting groove 372 of the tooth socket 37;

a positioning sleeve 39 provided with an upper positioning rod 40 is arranged on the upper surface of the upper body 32 and the lower part of the upper positioning rod 40 is inserted into the independent spring 34;

the positioning sleeve 39, the upper body 32 and the tooth socket 37 are all installed in the space formed by the upper joint 31 and the outer cylinder 38, and the tooth socket 37 is fixed by the lower positioning rod 41 installed in the outer cylinder 38.

In the present embodiment, the socket 37 is fixed in the outer cylinder 38 in the axial direction and the circumferential direction, and the fishing tool of the present embodiment is used to solve the problem of fishing a rod string dropped into a well by eccentric wear and corrosion fracture by the independent block 36 which can independently move along the dovetail groove 371 and the socket engaging teeth 373 in the cavity of the socket 37. When the independent tooth block 36 moves up and down along the dovetail groove 371 in the tooth seat 37, one surface of the independent tooth block 36 facing the axial direction of the fishing tool is always parallel to the central axis of the fishing tool, and the independent tooth block 36 is driven by the independent spring 34 and the independent push rod 35.

When the sucker rod body at the position of splitting in the sucker rod string falls into the well because of corruption and eccentric wear fracture, slightly rotatory fishing rod string makes the below be connected the utility model discloses in with its sucker rod independent tooth piece 36 corresponding in eccentric wear department remove to the eccentric wear face of the sucker rod body under the drive of independent spring 34, independent push rod 35, and be on a parallel with through it the utility model discloses the sucker rod body is firmly held in independent tooth piece 36 and the block tooth 373 of toothholder of the central axis direction, makes it salvage to ground smoothly.

In addition to the first embodiment, the second embodiment further includes the following embodiments:

the central lines of the inner drift diameters of the positioning sleeve 39, the upper body 32, the tooth holder 37 and the outer cylinder 38 are all offset on one side of the central line of the fishing tool; the upper positioning rod 40, the independent spring 34, the independent push rod 35, the independent tooth block 36 and the lower positioning rod 41 are all arranged on one axial line and positioned in the thick wall on the inner diameter side of the positioning sleeve 39, the upper body 32, the tooth seat 37 and the outer cylinder 38. In the embodiment, the inner drift diameter of the fishing tool is offset, and the number of the independent springs 34 and the independent push rods 35 is less, so that the outer diameter of the fishing tool can be smaller, the application range of the fishing tool is expanded, and the fishing tool can be applied to small-oil-pipe oil production wells.

The inner cavity of the tooth holder 37 consists of an offset central hole and a taper hole, the taper hole with a large top and a small bottom is positioned at one side of the dovetail groove 371, the straight hole is positioned at one side of the offset central hole, the inner wall of the straight hole is provided with a tooth holder clamping tooth 373, the dovetail groove 371 is arranged in the taper hole, and the independent tooth block 36 is arranged in the taper hole; the tooth holder clamping teeth 373 are reverse upper oblique teeth identical to the tooth block clamping teeth 361, and the tooth holder limiting grooves 372 are uniformly distributed in the upper end surfaces of the tooth holders 37 on the two sides of the dovetail groove 371; the lower end face of the tooth holder 37 is provided with a lower positioning rod insertion hole.

A tooth socket clamping tooth 373 is arranged on the inner side surface of the tooth socket limiting boss 321 opposite to the push rod assembling hole 322 in the lower end surface of the upper body 32; the lower positioning rod 41 is mounted in a lower positioning rod mounting hole in the outer cylinder 38, which is a blind hole having an upper end penetrating therethrough and a lower end closed or a threaded hole penetrating vertically therethrough.

The lower positioning rod mounting hole in the outer cylinder 38 corresponds to the lower positioning rod insertion hole in the tooth holder 37, and the length of the lower positioning rod 41 is greater than the depth of the lower positioning rod mounting hole in the outer cylinder 38; the lower inner cavity of the outer cylinder 38 is a tapered cavity with a small upper part and a large lower part, and has a guiding function on a well-falling sucker rod string.

The fishing tool can have an outer diameter greater than 48mm or equal to 48mm or less than 48 mm. Since the inner diameter of the present embodiment is an offset structure, the number of sets of the independent springs 34 and the independent push rods 35 installed therein is small, and the fishing process can be realized by installing only one set. The fishing tool in the embodiment has the outer diameter of less than 48mm, can be used for fishing the sucker rod string which falls into a well due to corrosion fracture in a two-inch small oil pipe, and enlarges the application range.

The structure of the individual blocks 36 in the present embodiment is the same as the structure of the individual blocks 36 in the first embodiment.

When the embodiment is used for salvaging the sucker rod string which falls into a well due to corrosion and eccentric wear, the salvaging tool of the embodiment is connected to the lower end of the salvaging rod string and is put into the well along with the salvaging rod string.

When the fishing tool reaches the upper part of the eccentric wear rod body of a well, the fishing tool continues to press the upper end part of the broken sucker rod and pushes the independent tooth block 36 to move upwards under the action of the self gravity of the fishing rod column, the independent tooth block 36 moves upwards and outwards along the dovetail groove 371 in the inner cavity of the tooth seat 37, so that the inner channel of the tool is expanded, and the broken sucker rod passes through the independent tooth block 36 and enters the tooth seat 37 and the upper body 32.

At this time, the fishing rod column and the fishing tool are lifted, the independent tooth block 36 moves downwards along the dovetail groove 371 and towards the eccentric wear surface direction of the broken sucker rod under the pushing of the independent spring 34 and the independent push rod 35, the independent tooth block 36 and the tooth seat clamping teeth 373 in the inner cavity of the tooth seat 37 tightly bite the rod body of the eccentric wear sucker rod from different directions, the fishing rod column is continuously lifted, and the fishing operation process can be smoothly completed.

The embodiment adopts an offset structure, the outer diameter of the tool can be below 48mm, and the broken sucker rod string in a two-inch small oil pipe can be conveniently fished.

The embodiments described above are merely exemplary embodiments, but the present invention is not limited to these embodiments, and those skilled in the art can make modifications without departing from the spirit and teaching of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof. Any modification, equivalent replacement, improvement and the like made within the spirit and inventive concept of the present invention should be included in the protection scope of the present invention. The scope of protection is therefore not limited to the description above.

Claims

1. The utility model provides a fishing tool of corruption eccentric wear well sucker rod post that falls, includes top connection and urceolus, characterized by:

2. The fishing tool for the sucker rod string in the corroded eccentric wear well as defined by claim 1, wherein the inner cavity of the upper body is a non-constant diameter inner cavity, the inner diameter of the upper inner cavity is larger than that of the lower inner cavity, an internal thread is arranged in the upper inner cavity and connected with the upper joint, and a push rod assembly hole is arranged in the wall of the lower inner cavity; the outer wall of the lower part of the upper body is provided with external threads which are connected with the threads on the upper part of the outer cylinder; the spacing boss of toothholder sets up at the lower terminal surface of the upper part of the body and sets up with the push rod pilot hole interval, and the medial surface of this spacing boss of toothholder is inclined plane down.

3. A fishing tool for a corrosion off-set well sucker rod string as claimed in claim 1 or 2, wherein a spring washer is further provided between the upper joint and the table surface between the upper and lower cavities of the upper body.

4. The fishing tool for the sucker rod string of the eroded eccentric wear well according to claim 1, wherein the inner cavity of the toothholder is a tapered inner cavity with a large top and a small bottom, and the dovetail grooves are arranged in the inner cavity of the toothholder, and the number of the dovetail grooves is the same as the number of the push rod assembly holes and the positions of the dovetail grooves correspond to the positions of the push rod assembly holes.

5. The fishing tool for the sucker rod string of the corroded eccentric wear well as defined by claim 4, wherein the integral structure of the independent tooth block is a triangular block with a wide upper part and a narrow lower part, the lower inclined surface of the triangular block is an arc surface provided with tooth block clamping teeth, two sides of the back surface of the lower inclined surface are provided with dovetails, and the tooth block clamping teeth are reverse upper inclined teeth; the independent tooth block is arranged in a dovetail groove in the inner cavity of the tooth base through a dovetail.

6. The fishing tool for the sucker rod string of the corroded eccentric wear well as defined by claim 4, wherein the outer cylinder is a non-constant diameter inner cavity, the upper inner cavity is provided with an internal thread connected with the upper body, the lower inner cavity is a conical inner cavity with a small upper part and a big lower part, and the toothholder is arranged on a table top formed between the upper inner cavity and the lower inner cavity.

7. The utility model provides a fishing tool of corruption eccentric wear well sucker rod post that falls, includes top connection and urceolus, characterized by:

the upper joint is in threaded connection with the outer cylinder;

8. The fishing tool for corroding sucker rod strings in eccentric wear wells as claimed in claim 7, wherein the central lines of the inner drift diameters of the positioning sleeve, the upper body, the tooth socket and the outer cylinder are all offset to one side of the central line of the fishing tool; the upper positioning rod, the independent spring, the independent push rod, the independent tooth block and the lower positioning rod are all arranged on one axis and are positioned in the thick wall on one side of the inner drift diameter of the positioning sleeve, the upper body, the tooth seat and the outer barrel.

9. The fishing tool for the sucker rod string in the corroded eccentric wear well as defined in claim 7 or 8, wherein the inner cavity of the tooth holder consists of an offset center hole and a tapered hole, the tapered hole with a large upper part and a small lower part is positioned at one side of the dovetail groove, the straight hole is positioned at one side of the offset center hole, the tooth holder clamping teeth are arranged on the inner wall of the straight hole, the dovetail groove is arranged in the tapered hole, and the independent tooth block is arranged in the dovetail groove; the tooth holder clamping teeth are reverse upper oblique teeth which are the same as the tooth block clamping teeth, and tooth holder limiting grooves are uniformly distributed in the upper end surfaces of the tooth holders on the two sides of the dovetail groove; the lower end face of the tooth holder is provided with a lower positioning rod insertion hole.

10. The fishing tool for the corrosion eccentric wear well sucker rod string as claimed in claim 7 or 8, wherein the inner side surface of the tooth seat limiting boss opposite to the push rod assembling hole in the lower end surface of the upper body is provided with a tooth seat clamping tooth; the lower positioning rod is arranged in a lower positioning rod mounting hole in the outer barrel, and the lower positioning rod mounting hole is a blind hole with the upper end communicated and the lower end plugged or a threaded hole with the upper end communicated and the lower end communicated.

11. The fishing tool for the sucker rod string in the corroded eccentric wear well as defined in claim 9, wherein the lower positioning rod mounting hole in the outer cylinder corresponds to the lower positioning rod insertion hole in the tooth holder, and the length of the lower positioning rod 41 is greater than the depth of the lower positioning rod mounting hole in the outer cylinder; the lower inner cavity of the outer cylinder is a conical cavity with a small upper part and a big lower part.

12. A fishing tool for eroding a rod string which has fallen into a well in accordance with claim 8, wherein the fishing tool has an outer diameter which can be greater than 48mm or equal to 48mm or less than 48 mm.