Mining gas drilling screen pipe structure

Abstract

The utility model relates to the technical field of screen pipes, and particularly discloses a mine gas drilling screen pipe structure which comprises a connecting hose, a hole sealing pipe and a plurality of screen pipe bodies. Thickened connecting assemblies are connected between the hole sealing pipe and the screen pipe bodies and between the screen pipe bodies so that the screen pipe bodies can be prevented from falling off when the screen pipe bodies are placed in a drill hole, and the hole sealing pipe and the screen pipe bodies can be prevented from falling off. By arranging the conical plug, the situation that when the screen pipe body enters a drill hole, the screen pipe body abuts against the drill hole, and consequently the screen pipe body cannot enter a proper position is avoided, and by arranging the thickened connecting assembly, the connecting strength between the hole sealing pipe and the screen pipe body and the connecting strength between the screen pipe bodies can be enhanced; and meanwhile, the friction strength between the screen pipe body and a drill hole can be reduced when the screen pipe body enters the drill hole.

Description

Technical Field

[0001] This utility model relates to the field of screen pipe technology, specifically to a structure of a mine gas drilling screen pipe. Background Technology

[0002] Drilling boreholes into soft coal seams or soft rock to pre-extract gas is an effective method for coal seam gas control. However, in soft coal seams or soft rock, borehole collapse is a serious problem during the extraction cycle, blocking the gas extraction channels and resulting in unsatisfactory gas control effects. Using screen pipe protection technology is an effective means to solve the problem of borehole collapse in soft coal seams or soft rock. The specific technical measures are as follows: screen pipes are lowered into the borehole until the bottom, using the inner hole of the screen pipe to form a gas extraction channel. Even if the borehole collapses, it will not block the internal channel of the screen pipe and affect gas extraction. Each screen pipe has a fixed length (e.g., 3m, 4.5m, etc.) and has male / female threads at both ends. When lowering the screen pipes, each screen pipe is screwed onto the borehole opening and pushed into the borehole one by one.

[0003] After drilling to the designed hole depth, the drilling rig needs to be run idle (without drilling) to clean and remove drill cuttings from the hole, ensuring that the drill cuttings are completely removed. For holes using water-based slag removal, after cleaning the hole, compressed air should be used to remove all water from the hole. When lowering the casing, a conical plug is installed at the top of the first screen pipe to reduce the resistance of the lowering screen pipe and to prevent the screen pipe from clogging. Screen pipes are connected to each other and to the sealing pipe using threaded connections, and the joints are thickened to prevent the joints from breaking or falling off during the lowering process.

[0004] In the existing technology, the screen tube front end uses a flat plug, and the lower tube is connected one by one using a plug-in type (or non-thickened joint). Since the inner wall of the borehole is not smooth, the longer the lower tube is, the greater the resistance, which can easily cause the lower tube to not be in place, the screen tube to fall off, the joint to break, etc., affecting the extraction effect. Utility Model Content

[0005] This utility model provides a structure for a mine gas drilling screen, which aims to solve the problem of screens easily falling off or breaking during the installation of the screens in related technologies.

[0006] A mining gas borehole screen structure includes: a connecting hose, a sealing pipe, and multiple screen bodies. The screen body is characterized in that a conical plug is provided at the end of the screen body, and thickened connecting components are connected between the sealing pipe and the screen body, and between the screen bodies themselves, to prevent the screen bodies from falling off when the screen body is placed into the borehole.

[0007] Its effects are as follows: by setting a conical plug, the screen tube body is prevented from abutting against the borehole when it enters the borehole, thus preventing the screen tube body from entering the appropriate position. By setting a thickened connecting component, the connection strength between the sealing pipe and the screen tube body, and between screen tube bodies, can be strengthened. At the same time, the friction intensity between the screen tube body and the borehole when it enters the borehole can be reduced.

[0008] Preferably, the thickened connecting assembly includes an internal threaded connector and an external threaded connector, which are respectively disposed between two adjacent screen tube bodies or between a screen tube body and a sealing tube; the screen tube bodies are connected by providing the internal threaded connector and the external threaded connector.

[0009] Preferably, both the internal threaded connector and the external threaded connector have a welding section on their outer periphery, and the diameter of the welding section is larger than the diameter of the screen tube body and the sealing tube; the connection of the screen tube body is strengthened by setting the welding section.

[0010] Preferably, the outer wall of the welded section is made of a wear-resistant material to prevent the screen tube body from wearing out too quickly.

[0011] Preferably, ball bearings can be provided on the outside of the welded section to reduce friction between the welded section and the inner wall of the borehole.

[0012] Preferably, the taper of the cone head on the conical plug is between 30 and 120 degrees.

[0013] By adopting the above technical solution, the beneficial effects of this utility model are as follows:

[0014] By providing a tapered plug at the end of the screen tube body, the end of the screen tube body can be prevented from pressing against the borehole when the screen tube enters the borehole. By providing thickened connecting components between the screen tube bodies and between the screen tube body and the sealing tube, the connection between the screen tube bodies and the sealing tube can be prevented from breaking when the screen tube is placed in the borehole. The thickened connecting components can also reduce the friction generated when the screen tube body slides in the borehole to a certain extent, thus making it easier to place the screen tube body into the predetermined position in the borehole. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model.

[0016] Figure 2 This is a schematic diagram of the thickened connecting component of this utility model.

[0017] Figure label:

[0018] 1. Connecting hose; 2. Sealing tube; 3. Screen tube body; 4. Conical plug; 5. Thickened connecting assembly; 51. Internal threaded connector; 52. External threaded connector; 53. Welded section. Detailed Implementation

[0019] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] like Figures 1-2 As shown, a mine gas borehole screen structure includes a connecting pipe, a sealing pipe 2, and multiple screen pipe bodies 3. The ends of the screen pipe bodies 3 are provided with conical plugs 4. Thickened connecting components 5 are connected between the sealing pipe 2 and the screen pipe bodies 3, and between the screen pipe bodies 3 themselves. When extracting gas, the screen pipe bodies 3 are connected and inserted into the borehole to extract the gas. Since the borehole is deep and the length of the screen pipe bodies 3 inserted into the borehole is long, thickened connecting components 5 are connected between the sealing pipe 2 and the screen pipe bodies 3, and between the screen pipe bodies 3 themselves, to prevent the screen pipes from falling off during operation. Since the inner wall of the borehole is not smooth, if the ends of the screen pipe bodies 3 are flat, they can easily abut against the inner wall of the borehole, which can cause the screen pipe bodies 3 to not be properly lowered.

[0021] The thickened connecting assembly 5 includes an internal threaded connector 51 and an external threaded connector 52. The internal threaded connector 51 and the external threaded connector 52 are respectively disposed between two adjacent screen tube bodies 3 or between the screen tube body 3 and the sealing tube 2. When the screen tube or the sealing tube 2 is placed into the borehole, the screen tube body 3 or the screen tube body 3 and the sealing tube 2 are connected through the internal threaded connector 51 and the external threaded connector 52 so that the screen tube body 3 can reach the predetermined position of the borehole.

[0022] Both the internal threaded connector 51 and the external threaded connector 52 are provided with a welding section on their outer periphery. The diameter of the welding section is larger than the diameter of the screen tube body 3 and the sealing tube 2. When the screen tube body 3 and the sealing tube 2 enter the borehole, the welding section contacts the inner wall of the borehole, which can reduce the contact area between the screen tube body 3 and the inner wall of the borehole to a certain extent, thus making it easier to place the screen tube body 3 into the predetermined position in the borehole.

[0023] Preferably, the outer wall of the welded section is made of a wear-resistant material, specifically polytetrafluoroethylene. When the welded section comes into contact with the inner wall of the borehole, it can play a certain role in wear resistance and prevent the screen tube body 3 from breaking when it is placed.

[0024] Specifically, ball bearings can be installed on the outside of the welded section; when the screen tube body 3 enters the borehole, the ball bearings can further reduce the friction between the welded section and the inner wall of the borehole, making it easier to place the screen tube body 3 into the borehole.

[0025] The taper of the cone on the conical plug 4 is between 30 and 120 degrees. When the screen tube body 3 is placed into the borehole, the conical plug 4 can prevent the end of the screen tube body 3 from hitting the inner wall of the borehole, thus preventing the screen tube body 3 from reaching the predetermined position.

[0026] One end of the sealing tube 2 is connected to a connecting hose 1. A sealing ring is provided between the connecting hose 1 and the sealing tube 2. The hose is fitted with an internal threaded connector 51 clamp. The hose is fixed to the sealing tube 2 by the internal threaded connector 51 clamp.

[0027] Working principle:

[0028] By providing a tapered plug 4 at the end of the screen tube body 3, the end of the screen tube body 3 can be prevented from pressing against the borehole when the screen tube enters the borehole. By providing a thickened connecting component 5 between the screen tube bodies 3 and between the screen tube body 3 and the sealing tube 2, the connection between the screen tube bodies 3 and between the screen tube body 3 and the sealing tube 2 can be prevented from breaking when the screen tube is placed in the borehole. By providing the thickened connecting component 5, the friction generated when the screen tube body 3 slides in the borehole can be reduced to a certain extent, thus making it easier to place the screen tube body 3 into the predetermined position in the borehole.

[0029] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A mine gas borehole screen structure, comprising a connecting hose (1), a sealing pipe (2), and multiple screen bodies (3), characterized in that, A tapered plug (4) is provided at the end of the screen tube body (3). Thickened connecting components (5) are connected between the sealing tube (2) and the screen tube body (3) and between the screen tube body (3) and the screen tube body (3) to prevent the screen tube body (3) from falling off between the screen tube bodies (3) and between the sealing tube (2) and the screen tube body (3) when the screen tube body (3) is placed into the borehole.

2. The structure of the mine gas borehole screen pipe according to claim 1, characterized in that, The thickened connecting assembly (5) includes an internal thread connector (51) and an external thread connector (52), which are respectively disposed between two adjacent screen tube bodies (3) or between the screen tube body (3) and the sealing tube (2).

3. The structure of the mine gas borehole screen pipe according to claim 1, characterized in that, Both the inner threaded connector (51) and the outer threaded connector (52) have a welding section on their outer periphery. The diameter of the welding section is larger than the diameter of the screen tube body (3) and the sealing tube (2).

4. The structure of the mine gas borehole screen pipe according to claim 3, characterized in that, The outer wall of the welded section is made of wear-resistant material.

5. The structure of the mine gas borehole screen according to claim 1, characterized in that, Ball bearings can also be installed on the outside of the welded section.

6. The mine gas borehole screen structure according to any one of claims 1-5, characterized in that, The taper of the cone on the cone plug (4) is between 30 and 120 degrees.

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