CN110965954A

CN110965954A - Hydraulic fishing tool

Info

Publication number: CN110965954A
Application number: CN201911363351.8A
Authority: CN
Inventors: 惠城; 彭晓龙; 任威严; 汪海阁; 邹灵战; 卓鲁斌; 于璟; 常龙
Original assignee: CNPC Engineering Technology R&D Co Ltd
Current assignee: CNPC Engineering Technology R&D Co Ltd
Priority date: 2019-12-26
Filing date: 2019-12-26
Publication date: 2020-04-07

Abstract

The invention relates to a hydraulic fishing tool, which can frequently cause underground complex accidents such as drilling tool jamming and the like in the drilling process, particularly common accidents such as casing local abrasion and the like in a horizontal well section with an irregular well bore under complex geological conditions and finally causing underground fish falling and the like, steel wire disconnection and the like in the well completion electrical testing process, and the like. Therefore, a hydraulic fishing tool is designed, which can salvage falling objects within a certain size range and mainly comprises: the fishing claw is installed on the fishing tool outer barrel through the fixed key, the hydraulic power provided by the drilling fluid pushes the hydraulic push block to slide, and the sliding of the hydraulic block drives the fishing claw to move, so that the underground falling objects are captured.

Description

Hydraulic fishing tool

Technical Field

The invention relates to the technical field of underground fishing tools, in particular to a hydraulic fishing tool

Background

Along with the continuous development of unconventional oil and gas resources, the drilling depth is deeper and deeper, the well type is more and more complex, the complexity in the drilling process is more and more, the drill string is easily worn in the stratum with large inclination angle, poor drillability and strong stratum abrasiveness of a part of stratum, and the drilling tool is finally broken to form underground fish; in addition, the accident that the steel wire rope is broken is released in the electrical measurement process of well completion, but the salvage of underground falling objects is not ideal, the falling objects are difficult to pull out, and the side drilling of the injection plug is caused.

Some existing fishing tools are fixed in size or fixed in use, can only salvage tools with certain outer diameters, are generally cylindrical falling objects, cannot effectively salvage small and soft underground falling objects which are similar to cables and have no regular shape, and are complex in operation, low in success rate and long in time.

Disclosure of Invention

The invention provides a hydraulic fishing tool, which combines an arc-shaped fishing claw, a hydraulic power device, a fishing outer cylinder and the like to provide a fishing tool with variable diameter for fishing various irregular and fixed-shaped underground falling objects, thereby solving the problems mentioned in the background technology.

In order to solve the above-mentioned difficult problems, the technical scheme provided by the invention is as follows: a hydraulic fishing tool; the fishing claw is locked on the outer barrel of the fishing tool through a small fixed key, and the fishing claw moves in the small annular groove through the fixed key when the fishing tool works, so that the fishing claw is opened and closed; 3 gaps are uniformly distributed on the outer cylinder of the fishing tool in a circle, each fishing claw is positioned in one gap, the gaps play a role in limiting the movement of the fishing claws, the fishing claws only rotate in one plane, and the fishing claws are uniformly distributed around the outer cylinder of the fishing tool and are spaced at 120 degrees.

The hydraulic device is positioned at the upper part of the outer cylinder of the fishing tool and is a sealed device, the hydraulic device mainly comprises a high-temperature-resistant sealing rubber plug and a hydraulic push block, drilling fluid is injected into the hydraulic cylinder to push the hydraulic push block to move, the hydraulic push block drives the fishing claw to move, the upper part of the fishing claw expands outwards, the lower part of the fishing claw is tightened, and then falling objects are tightly grasped and lifted through a drill column to be taken out of a shaft.

The upper end of the fishing claw enters the fishing tool outer cylinder for a certain distance, 3 groups of springs are welded on the inner wall surface of the fishing tool outer cylinder, one section of the springs is connected to the inner wall surface of the fishing tool outer cylinder, and the other section of the springs is welded on the outer wall surface of the upper part of the fishing claw, so that the upper part of the fishing tool can be gathered towards the center through the elasticity of the springs when no drilling fluid is pressurized, and the lower part of the fishing claw opens along with the upper part.

The invention has the following advantages:

the hydraulic fishing tool has the advantages of simple working principle, easy operation, simple operation and capability of controlling the fishing process by controlling the pumping amount of the drilling fluid in the drilling pipe.

The hydraulic fishing tool is provided with 3 fishing claws, the opening degree of the lower part of the fishing claw is adjusted by adjusting the balance of hydraulic pressure and a spring, a certain catching range is achieved, and the hydraulic fishing tool can only salvage a tool with a fixed size and a shape, so that the hydraulic fishing tool has a wider application range.

The lower end of the hydraulic fishing tool is only the lower end of 3 fishing claws, and other cylindrical tools with fixed diameters are not provided, so that the hydraulic fishing tool has larger variation in well deviation or is not easy to cause drilling clamping accidents in a diameter-reduced gypsum stratum; the lower end of the salvaging claw is provided with a barb, so that tools and equipment without fixed shapes, such as cables, steel wire ropes and the like, can be salvaged; the lower part of the fishing claw adopts an arc design, the surface of the lower part becomes smooth through polishing treatment, and the barb of the fishing claw can hook a falling object through pressurization of a drill column in the process that the fishing tool is lowered and fish cannot be lowered.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used for describing the embodiments will be briefly introduced below.

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of the fishing claw of the present invention;

fig. 3 is a diagram of the hydraulic apparatus of the present invention.

In the drawings, the components represented by the respective reference numerals are listed below:

1. the fishing tool comprises a fishing claw, 2 parts of a hydraulic power device, 3 parts of a fishing tool outer cylinder, 4 parts of a barb, 5 parts of connecting threads, 6 parts of a hydraulic push block, 7 parts of an outer cylinder notch, 8 parts of an annular small groove, 9 parts of a drilling fluid flow passage, 10 parts of a spring, 11 parts of a fixed key and 12 parts of a hydraulic groove.

Detailed Description

The following description of the complete operation flow of the hydraulic fishing tool in connection with the three drawings of the present invention

Referring to fig. 1, the hydraulic fishing tool mainly comprises (1) a fishing claw, (2) a hydraulic power device, (3) a fishing tool outer cylinder and (5) connecting threads, wherein the connecting threads (5) are positioned at the uppermost end of the design, and the tool is connected to the lowermost end of a drill string through the connecting threads (5) to perform fishing operation; (1) the fishing claw is a main catching tool, the (11) fixing key penetrates through the (8) small annular groove, so that the (1) fishing claw is fixed on the (3) fishing tool outer cylinder, (1) the fishing claw can only rotate at the (7) outer cylinder notch part, (1) the upper end of the fishing claw is positioned in the (3) fishing tool outer cylinder, as shown in figure 3, the inner wall surface of the (3) fishing tool outer cylinder is connected with the outer side of the (1) fishing claw through a (10) spring, the lower part of the (1) fishing claw is designed to be arc-shaped and is provided with (4) barbs, and the hydraulic fishing tool designed by the invention has 3 fishing claws (1) and is uniformly distributed on the (3) fishing tool outer cylinder.

Referring to fig. 2 and 3, the hydraulic fishing tool is first connected to the lower end of the drill string by (5) connecting threads, and during the lowering of the drill string, a certain amount of drilling fluid is pumped into the drill string, and simultaneously the drilling fluid flows into (9) the drillThe well fluid runner, the drilling fluid gives (6) hydraulic pressure ejector pad an outside thrust, meanwhile (10) the elasticity of spring impel (1) salvage the upper portion of the claw to move to the centre, under this two forces balanced action (1) salvage the claw and is in the vertical state, when the drilling string is gone into and meets the position of blocking, suck some drilling fluid in the drilling string backward through the ground apparatus, the elasticity of (10) the spring is greater than the drilling fluid and gives (6) the external extrusion force of hydraulic pressure ejector pad at this moment, (1) salvage the claw lower part from B₂Move to B₁Position, (8) annular groove around (11) fixed key from A₂Move to A₁The position, (11) the fixed key moves from the position of contacting with the lower end of the annular small groove (8) when the fishing claw (1) is closed to the position of contacting with the upper end of the annular small groove (8), the process is the opening process of the fishing claw (1), then a certain pressure is applied to the drill string, the lower end of the fishing claw (1) is tightly attached to the well wall to move downwards, after the fishing claw moves downwards for a certain distance, the drilling fluid pressurizes in the drill string, the drilling fluid pushes a hydraulic push block (6), a spring is compressed, and the lower part of the fishing claw (1) is compressed from the lower part of the fishing claw (B)₁Move to B₂，

(8) The small annular groove is arranged around the fixing key A (11)₁Move to A₂And (2) completing (1) the grasping process of the fishing claw in the process, locking the underground falling object and finally completing the operation of fishing the underground falling object.

The hydraulic fishing device designed by the invention can control the force of the drilling fluid to the hydraulic push block (6) by adjusting pumping pressure fishing, so that the hydraulic push block (6) and the spring (10) can be balanced within a certain range, and even if the size of underground falling objects is changed, the fishing of the underground falling objects with different sizes can be carried out by only adjusting the balance of the pumping pressure and the spring (10) and controlling the opening degree of the fishing claw (1); because (1) salvage claw lower part design for the arc, can play and reduce frictional resistance, reduce the possibility of meeting the card and designed (4) barb, if the shaft bottom junk is not regular shape, soft article such as cable, wire rope, can hook it through (4 barbs), tighten up 3 salvage claws through adjusting the pump pressure, carry out the salvage of rope class article.

The upper part, the lower part, the left part and the right part in the description are all referred to the attached drawings, the reference drawings are only schematic diagrams and are only used for explaining the design without strict size marks, the working process of 1 (1) fishing claws is only described in the description principle process, and the rest (1) fishing claws are all the same principle.

Claims

1. A hydraulic fishing tool, its essential features includes: (1) the fishing claw is locked on the outer cylinder of the fishing tool (3) through a fixing key (11); (2) the hydraulic power device is positioned on the upper part of the outer cylinder of the fishing tool (3), and the upper part of the hydraulic power device (2) is provided with connecting threads (5) which are connected to the middle of a drill column through the threads.

2. A hydraulic fishing tool as defined in claim 1, wherein: (1) the fishing claws are 3 and are uniformly distributed on the fishing tool outer cylinder (3), and the fishing claw (1) is divided into two parts, namely an upper linear part and a lower arc part, and the lower part is provided with a barb (4).

3. A hydraulic fishing tool as defined in claim 1, wherein: (1) the upper part of the fishing claw is positioned in the small annular space between the hydraulic push block (6) and the fishing tool outer cylinder (3).