CN215860072U

CN215860072U - Hydraulic overshot

Info

Publication number: CN215860072U
Application number: CN202122095760.3U
Authority: CN
Inventors: 孙新成; 李中华; 柴英; 赫珍; 李天聪; 孙新建
Original assignee: China Petroleum and Chemical Corp
Current assignee: China Petroleum and Chemical Corp
Priority date: 2021-09-01
Filing date: 2021-09-01
Publication date: 2022-02-18
Anticipated expiration: 2031-09-01

Abstract

The utility model relates to the technical field of fishing tools for underground operation in oil extraction engineering, in particular to a hydraulic fishing barrel. The hydraulic overshot comprises a cylinder body, a piston and grabbing teeth; the barrel is provided with an upper joint for connecting with a fishing pipe column, and a containing cavity for containing falling objects or falling object fish tops is arranged in the barrel; the piston is arranged in the cylinder body and is provided with a channel which is communicated up and down and can be sealed by a lost ball, and a shear pin is arranged between the cylinder body and the piston; the more than two grabbing teeth are arranged below the piston and around the axis of the cylinder body, and a guide structure which guides the grabbing teeth to contract inwards when the grabbing teeth move downwards is arranged at the position, close to the lower port, of the cylinder body. The shearing nail can be cut off and the grabbing teeth are driven to move downwards by pressing the piston, the grabbing teeth shrink towards the center of the barrel under the action of the guide structure, so that the fish top of the falling object can be fixed or sealed in the accommodating cavity of the barrel, the falling object is prevented from being separated from the barrel when the fishing pipe column is lifted, and the problem that the fishing success rate of the existing fishing device is low is solved.

Description

Hydraulic overshot

Technical Field

The utility model relates to the technical field of fishing tools for underground operation in oil extraction engineering, in particular to a hydraulic fishing barrel.

Background

In the production and operation processes of oil-water wells, small falling objects such as pipe plugs, valve ball packer rubber cylinders, rubber parts and the like fall into the wells frequently. At present, the main methods adopted by each oil field for fishing small fallen objects are three types: firstly, the next grappling barrel is used for fishing, secondly, the lower grinding shoe grinds and washes out small fallen objects, and thirdly, the lower inner fishing hook is used for fishing.

The structure of a grabbing, salvaging and throwing barrel is described in patent specification with publication number CN204703819U and comprises an upper joint, wherein the upper joint is cylindrical, an inner thread used for being connected with a salvaging pipe column is arranged on the inner wall of the upper joint, a plurality of grabbing hooks are fixedly arranged on the inner wall of the upper joint, the grabbing hooks are uniformly distributed around the central line of the upper joint, and the bottom of each grabbing hook extends downwards to the outside of the upper joint and bends inwards. When the fishing device is used, a fishing barrel is put into a well through the connection of a fishing pipe column and an upper joint, the top of a falling object enters into an accommodating cavity surrounded by the grapple or a gap between adjacent grapples in the process of putting the fishing barrel down, then the fishing barrel is pressurized and rotated, and the grapple which is bent and deformed forms a spiral shape according to the rotating direction of the grapple, so that the falling object is held tightly or clamped by the grapple and fished. However, in actual production, one grappling barrel can lead the falling objects into the grappling barrel, but the grapple can not be completely folded in the fishing process due to the irregular bottom hole or top of the artificial well, and the fishing effect is poor.

Although the milling shoe can mill steel parts, the fish tops of falling objects such as the screw plug, the valve ball and the rubber part are unstable, and the falling objects are easy to slide, move or rotate together with the milling shoe in the milling process, so that the milling effect is influenced, and particularly when the falling objects are the rubber parts, the milling effect is worse.

The patent specification with the publication number of CN203230366U discloses a downhole junk overshot, which is an inner hook type overshot and comprises an upper joint and a cylinder body, wherein the upper joint is used for being connected with a fishing pipe column, a piston is arranged in the cylinder body, a channel is arranged at the center of the piston, a shear pin is arranged between the cylinder body and the piston, and an inner hook is arranged at the lower end of the piston. During operation, the fishing barrel is lowered into the top of a falling object in the well through the fishing pipe column, the top of the falling object is introduced into the barrel, the piston is pushed through ball throwing and liquid adding pressure to the fishing pipe column, the piston shears the shear pin to move downwards, the inner hook is driven to fix the top of the falling object, and finally the fishing pipe column is lifted to complete fishing operation. Although the inner hook can carry part of the broken rubber out of the shaft in fishing, the inner hook is not firmly hung due to the easy movement and large elasticity of the rubber, and the success rate of one-time fishing is also low.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a hydraulic overshot to solve the problem that the fishing success rate of the existing fishing device is low.

In order to achieve the purpose, the hydraulic overshot adopts the following technical scheme: a hydraulic overshot, comprising:

the fishing device comprises a barrel body, a fishing rod and a fishing rod, wherein the barrel body is provided with an upper joint for connecting with a fishing string, and a containing cavity for containing falling objects or falling object fish tops is arranged in the barrel body;

the piston is arranged in the cylinder body, is provided with a channel which is communicated up and down and can be sealed by a lost ball, and a shear pin is arranged between the cylinder body and the piston;

the more than two grabbing teeth are arranged below the piston and arranged around the axis of the cylinder body, and a guide structure which guides the grabbing teeth to contract inwards when the grabbing teeth move downwards is arranged at the position, close to the lower port, of the cylinder body.

Has the advantages that: the piston is arranged in the cylinder body of the hydraulic fishing cylinder, and the guide structure is arranged at the position, close to the lower port, of the cylinder body, when the hydraulic fishing cylinder is used, the shear pin can be sheared by pressing the piston, the gripping teeth are driven to move downwards by the downward movement of the piston, and the gripping teeth shrink towards the center of the cylinder body under the action of the guide structure in the downward movement process, so that the top of a fish with fallen objects can be fixed in the accommodating cavity of the cylinder body, or the fallen objects are integrally sealed in the accommodating cavity, the fallen objects are prevented from being separated from the cylinder body when a fishing pipe column is lifted, and the problem of low success rate of the conventional fishing device is solved.

Further, the guide structure is a guide surface provided on an inner wall of the cylinder. The guide surface is used as a guide structure, so that the processing is convenient and the reliability is good.

Still further, the guide surface is an arc-shaped surface. The arc-shaped surface has better smoothness as a guide surface, and can avoid clamping stagnation of the grabbing teeth.

Furthermore, the inner wall of the barrel is provided with a guide groove which is a dovetail groove, the grabbing teeth are arranged in the corresponding guide grooves, and the guide surface is formed by the bottom surfaces of the guide grooves at the corresponding positions. The guide groove of dovetail groove structure can play the effect that whole restraints of circumference are played to grabbing the tooth, and the deformation of grabbing the tooth can be better controlled.

Furthermore, the upper end of the grabbing tooth is fixedly connected with the piston. The upper end of the grabbing tooth is connected with the piston, so that the grabbing tooth can be better prevented from moving downwards automatically.

Furthermore, the inner wall of the cylinder body is provided with a step surface facing the piston, and the step surface forms a limiting surface of the piston. The step surface can limit the stroke of the piston, and damage or failure caused by overlong stroke of the grabbing teeth is avoided.

Furthermore, the barrel comprises an upper barrel and a lower barrel, the upper barrel is in threaded connection with the lower barrel, and the step surface is formed by the upper end surface of the lower barrel. The cylinder body divided into the upper cylinder body and the lower cylinder body forms an openable structure, so that the piston can be more conveniently installed and the teeth can be grabbed.

Still further, the number of the gripping teeth is more than three. More than three grabbing teeth can better play a role in grabbing falling objects.

Still further, the gripping teeth are each made of a steel strip. The steel bar has better elasticity and strength, and can grasp falling objects more reliably.

Furthermore, the lower end of the cylinder body is provided with a bell mouth. The bellmouth is more favorable to the junk to get into and hold the chamber.

Drawings

FIG. 1 is a schematic structural view of a hydraulic overshot according to the utility model;

fig. 2 is a sectional view a-a of fig. 1.

In the figure: 101. a barrel; 11. an upper joint; 12. an accommodating chamber; 13. guiding a shoe; 14. necking; 15. an upper cylinder body; 16. a lower cylinder body; 17. shearing the nails; 18. an O-shaped sealing ring; 19. a guide groove; 102. a piston; 103. and (5) grabbing teeth.

Detailed Description

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 detailed description and specific examples, while indicating the preferred embodiment of the utility model, are intended for purposes of illustration only and are not intended to limit the scope of the utility model. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that relational terms such as "first" and "second," and the like, which may be present in the embodiments of the present invention, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the statement that "comprises an … …" is intended to indicate that there are additional elements of the same process, method, article, or apparatus that comprise the element.

In the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" when they are used are to be construed broadly, e.g., as meaning a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those skilled in the art from specific situations.

In the description of the present invention, unless otherwise specifically stated or limited, the term "provided" may be used in a broad sense, for example, the object of "provided" may be a part of the body, or may be arranged separately from the body and connected to the body, and the connection may be detachable or non-detachable. The specific meaning of the above terms in the present invention can be understood by those skilled in the art from specific situations.

The present invention will be described in further detail with reference to examples.

The embodiment of the hydraulic overshot of the utility model is as follows:

as shown in fig. 1-2, the hydraulic overshot comprises a cylinder 101, a piston 102 and gripping teeth 103.

The upper end of the barrel body 101 is provided with an upper connector 11, an internal thread is arranged in the upper connector and used for being connected with a fishing pipe column, a containing cavity 12 is arranged in the barrel body 101, and the containing cavity 12 is used for allowing the whole falling objects in the well to enter or allowing the fish tops of the falling objects in the well to enter so as to contain the falling objects or the fish tops of the falling objects. A guide shoe 13 is formed with a flare provided at the lower end of the barrel 101 to better catch the fall. Above the flare, the barrel 101 is further provided with a reduced internal diameter constriction 14 to act as a shield and guide for the gripping tooth 103, as will be described in more detail in the following description. In this embodiment, the cylinder 101 is a separate structure including an upper cylinder 15 and a lower cylinder 16, and the upper cylinder 15 is screwed to the lower cylinder 16, in this embodiment, an external thread is provided at the upper end of the lower cylinder 16, a corresponding external thread is provided at the lower end of the upper cylinder 15, and a downward step surface is provided on the inner wall surface of the upper cylinder 15, and the step surface can limit the lower cylinder 16; meanwhile, the upper end surface of the lower cylinder 16 also forms an upward step surface, and the step surface forms a limiting surface of the piston 102 and can limit the downward stroke of the piston 102. The receiving chamber 12 is mainly distributed in the inner bore of the lower cylinder 16, and the inner bore of the upper cylinder 15 forms a piston chamber cooperating with the piston 102.

The piston 102 is mounted at an upper position in the cylinder 101, the top of the piston is limited by a shoulder arranged on the upper cylinder 15 of the cylinder 101, and the lower end of the piston is limited by a shear pin 17 arranged on the side wall of the upper cylinder 15 of the cylinder 101. An O-shaped sealing ring 18 is arranged on the outer wall of the piston 102, and is in sealing fit with the inner wall of the cylinder 101 through the O-shaped sealing ring 18. The piston 102 is provided with a channel which is communicated up and down to form a ball seat structure, when in use, the channel of the piston 102 can be sealed by the valve ball 104, and then the shear pin 17 is cut off by pressing at a well mouth, so that the piston 102 is pushed to move downwards.

The grabbing teeth 103 are arranged in the barrel body 101, a guide structure is arranged at the position, close to the lower port, of the barrel body 101, when the grabbing teeth 103 move downwards, the guide structure can drive the lower ends of the grabbing teeth 103 to be inward, namely the center of the barrel body 101 is drawn close, so that the falling objects can be grasped, in the embodiment, in order to achieve reliable grasping of the falling objects, the grabbing teeth 103 are four in number and are uniformly arranged around the axis of the barrel body 101. The upper end of each grabbing tooth 103 is connected to the lower end face of the piston 102, and when the piston 102 moves downwards, the grabbing teeth 103 can be pushed to move downwards; the inner wall of the barrel 101, in particular the inner wall of the lower barrel 16 of the barrel 101, is provided with a guide groove 19, the guide groove 19 is a dovetail groove, namely the width of the groove opening is smaller than the width of the groove bottom, the grabbing teeth 103 are made of steel bars, and the steel bars are arranged in the corresponding guide grooves, and the width of the steel bars is larger than the width of the guide groove 19, so that the steel bars cannot be separated from the guide groove 19; the guide structure is formed by an arcuate groove bottom at the lower end of the guide groove 19. When the grabbing teeth 103 close the lower opening of the lower cylinder 16, the piston 102, the upper cylinder 15, the lower cylinder 16 and the grabbing teeth 103 together enclose a relatively closed cavity, so that the caught falling objects are prevented from falling out. The above-mentioned constriction at the lower port of the cylinder 101 may serve to shield the lower end of the gripping tooth 103 to prevent downhole debris from interfering with the gripping tooth 103 when entering the cylinder 101.

In the process of fishing operation, the hydraulic fishing barrel is connected to the lower end of the oil pipe and is put into a well, when the lower barrel 16 is put to a position 2-3 meters above the top of a fish, a pump is started for backwashing, and well washing liquid passes through the lower part of the lower barrel 16, passes through the inner cavity of the hydraulic fishing barrel and is discharged back to the ground. The hydraulic overshot is slowly lowered while washing, and in the lowering process, the fishing pipe column is rotated positively to enable the fish top to enter the lower barrel body 16, at the moment, the pump pressure rises, and the falling fish enters the accommodating inner cavity through the guide shoe 13 under the action of the pump pressure. Stopping the pump, throwing the valve ball 104 from the oil pipe, when the valve ball 104 is located on the piston 102, starting the pump to press the oil pipe, pushing the piston 102 to move downwards, cutting off the shear pin 17, driving the grabbing teeth 103 to move downwards along the guide groove by the piston 102, bending inwards at the lower cylinder opening of the lower cylinder 16 under the guide of the guide groove by the grabbing teeth 103 to extend out of the lower port of the guide groove, stopping the piston 102 when the piston 102 moves downwards until the lower end surface abuts against a horizontal shoulder at the upper end of the lower cylinder 16, converging the grabbing teeth 4 extending out of the lower port of the guide groove to close the lower cylinder opening of the lower cylinder, stopping the pump, starting a fishing pipe column, unloading the fishing cylinder from the oil pipe, and disassembling the threaded connection part of the upper cylinder 1 and the lower cylinder 2 to take out the falling objects.

In other embodiments of the utility model, the number of the gripping teeth can be more than two; the tops of the grabbing teeth can be connected with each other to form a structure of the grabbing hand; the guiding structure can also be only a guiding inclined plane or a cambered surface arranged at the lower opening of the cylinder body.

The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention, the scope of the present invention is defined by the appended claims, and all structural changes that can be made by using the contents of the description and the drawings of the present invention are intended to be embraced therein.

Claims

1. The hydraulic overshot is characterized by comprising a barrel body (101), a piston (102) and grabbing teeth (103), wherein the barrel body (101) is provided with an upper connector (11) used for being connected with a fishing string, and a containing cavity (12) used for containing falling objects or falling object fish tops is arranged in the barrel body (101); the piston (102) is arranged in the cylinder body (101) and is provided with a channel which is through up and down and can be sealed by lost balls, and a shear pin (17) is arranged between the cylinder body (101) and the piston (102); the more than two gripping teeth (103) are arranged below the piston (102) and around the axis of the cylinder body, and a guide structure for guiding the gripping teeth (103) to contract inwards when the gripping teeth (103) move downwards is arranged at the position, close to the lower port, of the cylinder body (101).

2. The hydraulic overshot according to claim 1, characterised in that the guiding structure is a guiding surface provided on the inner wall of the barrel (101).

3. The hydraulic overshot according to claim 2, characterised in that the guide surface is an arc shaped surface.

4. A hydraulic overshot according to claim 2 or 3, characterized in that the inner wall of the barrel (101) is provided with guide grooves (19), the guide grooves (19) being dovetail grooves, the gripping teeth (103) being mounted in the corresponding guide grooves (19), the guide surfaces being constituted by the bottom surfaces of the guide grooves (19) at the respective positions.

5. A hydraulic overshot according to claim 1, 2 or 3, characterised in that the upper end of the gripping tooth (103) is fixedly connected to the piston (102).

6. The hydraulic overshot according to claim 5, characterized in that the inner wall of the cylinder (101) is provided with a step surface facing the piston (102), which step surface forms a limit surface for the piston (102).

7. The hydraulic overshot according to claim 6, characterized in that the cylinder (101) comprises an upper cylinder (15) and a lower cylinder (16), the upper cylinder (15) and the lower cylinder (16) being in threaded connection, the step surface being constituted by the upper end surface of the lower cylinder (16).

8. A hydraulic overshot according to claim 1, 2 or 3, characterised in that the number of gripping teeth (103) is more than three.

9. A hydraulic overshot according to claim 1 or 2 or 3, characterised in that the gripping teeth (103) are each made of steel rod.

10. A hydraulic overshot according to claim 1, 2 or 3, characterised in that the lower end of the cylinder (101) is flared.