Multi-stage sealing structure for gas extraction drilling in inclined coal seam

Abstract

The utility model discloses a kind of inclined coal seam gas extraction borehole multistage sealing structure. Inclined coal seam gas extraction borehole multistage sealing structure includes: extraction pipe, front limiting air bag and rear limiting air bag are installed on the extraction pipe, pressure compensation air bag is installed on the sealing section of the extraction pipe;Grouting pipe and reflux pipe are installed on the rear limiting air bag, one end of the grouting pipe is close to the front limiting air bag, one end of the reflux pipe is close to the rear limiting air bag. The inclined coal seam gas extraction borehole multistage sealing structure provided by the utility model can realize multistage sealing of gas extraction hole by installing front limiting air bag, rear limiting air bag, pressure compensation air bag, grouting pipe and reflux pipe on extraction pipe, has better sealing effect, and effectively reduces grouting usage, saves grouting time.

Description

Technical Field

[0001] This utility model relates to the field of drilling and sealing technology for extraction holes, and in particular to a multi-stage sealing structure for inclined coal seam gas extraction drilling holes. Background Technology

[0002] Mine gas is a general term for various harmful gases, primarily methane, that emerge from coal and rock during coal mining operations. It is a major natural factor that seriously threatens the safe production of coal mines. Gas disasters cause enormous casualties and property losses; therefore, preventing gas disasters is of great significance to the healthy and sustainable development of the coal industry. Currently, gas drainage is an important means of controlling gas in mine operations. During gas drainage, it is necessary to ensure that the borehole is tightly sealed and has a long sealing length to ensure the effectiveness of gas drainage.

[0003] However, in order to better extract gas from inclined coal seams, the extraction hole is aligned with the inclined hole. If the conventional method is used, the sealing material is directly injected into the gap between the extraction pipe and the borehole to achieve the sealing of the sealing section. This requires a lot of sealing material and a long grouting time.

[0004] Therefore, it is necessary to provide a multi-stage sealing structure for inclined coal seam gas drainage boreholes to solve the above-mentioned technical problems. Utility Model Content

[0005] In response to the above situation and to overcome the shortcomings of existing technology, this utility model provides a multi-stage sealing structure for inclined coal seam gas extraction boreholes, which can effectively reduce the amount of grout used and save grouting time.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] The multi-stage sealing structure for inclined coal seam gas drainage boreholes includes: a drainage pipe, a front limiting airbag and a rear limiting airbag installed on the drainage pipe, and a pressure replenishing airbag installed on the sealing section of the drainage pipe; a grouting pipe and a return pipe are installed on the rear limiting airbag, with one end of the grouting pipe close to the front limiting airbag and one end of the return pipe close to the rear limiting airbag.

[0008] Preferably, a first support tube is fixedly installed on the inner side of the pressure-replenishing airbag, and a support frame is fixedly installed between the first support tube and the extraction tube.

[0009] Preferably, a first inflation / deflation tube that connects to the pressure-replenishing airbag is fixedly installed inside the first support tube.

[0010] Preferably, a second support tube is fixedly installed on the inner side of the front limiting airbag, and a second inflation / deflation tube communicating with the front limiting airbag is installed on one side of the second support tube.

[0011] Preferably, a third support tube is fixedly installed on the inner side of the rear limiting airbag, and a third inflation / deflation tube communicating with the rear limiting airbag is installed on the third support tube.

[0012] Preferably, the third support tube has multiple mounting holes.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) By installing a front limiting airbag, a rear limiting airbag, a pressure replenishing airbag, a grouting pipe and a return pipe on the extraction pipe, this utility model can achieve multi-stage sealing of the gas extraction hole, which has a better sealing effect and effectively reduces the amount of grout used and saves grouting time.

[0015] (2) By setting the first support tube, this utility model can conveniently support and fix the pressure-replenishing airbag, and can help improve the structural strength of the extraction hole sealing section.

[0016] (3) This utility model can make the inflation and deflation of the pressure-replenishing airbag by fixing a first inflation and deflation pipe connected to the pressure-replenishing airbag inside the first support tube.

[0017] (4) By setting a second support tube and installing a second inflation / deflation tube, this utility model can conveniently support and inflate / deflate the front limiting airbag;

[0018] (5) By setting a third support tube and installing a third inflation / deflation tube, this utility model can conveniently support and inflate / deflate the rear limiting airbag;

[0019] (6) This utility model has multiple mounting holes along the length of the third support pipe, which facilitates the installation of the grouting pipe, return pipe, first air filling and venting pipe and second air filling and venting pipe. Attached Figure Description

[0020] Figure 1 A schematic diagram of the multi-stage sealing structure for inclined coal seam gas extraction boreholes provided by this utility model;

[0021] Figure 2 for Figure 1 The diagram shows the installation structure of the pressure-replenishing airbag in the multi-stage sealing structure of the inclined coal seam gas extraction borehole.

[0022] Figure 3 for Figure 1 The diagram shows the structure of the front limiting airbag in the multi-stage sealing structure of the inclined coal seam gas extraction borehole.

[0023] Figure 4 for Figure 1 The diagram shows the structure of the rear limiting airbag in the multi-stage sealing structure of the inclined coal seam gas drainage borehole.

[0024] The corresponding names of the attached figures are: 1-extraction pipe, 2-front limiting airbag, 3-rear limiting airbag, 4-pressure replenishing airbag, 5-grouting pipe, 6-return pipe, 7-first support pipe, 8-support frame, 9-first inflation / deflation pipe, 10-second support pipe, 11-second inflation / deflation pipe, 12-third support pipe, 13-third inflation / deflation pipe, 14-mounting hole. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments.

[0026] Example 1:

[0027] like Figure 1-4As shown, the multi-stage sealing structure for inclined coal seam gas extraction borehole provided by this utility model includes: extraction pipe 1, front limiting airbag 2 and rear limiting airbag 3 installed on extraction pipe 1, pressure replenishing airbag 4 installed on the sealing section of extraction pipe 1, the front limiting airbag 2 and rear limiting airbag 3 are separated from the two ends of pressure replenishing airbag 4 by a certain distance of 10-20cm, and a grouting pipe 5 and a return pipe 6 are installed through and sealed on the rear limiting airbag 3, one end of grouting pipe 5 (discharge port) is close to the front limiting airbag 2, and one end of return pipe 6 (return port) is close to the rear limiting airbag 3. In use, after inserting the extraction pipe 1 into the gas extraction hole of the inclined coal seam at a predetermined depth, inflate the forward limiting airbag 2 and the rear limiting airbag 3, causing them to expand and press tightly against the inner wall of the extraction hole, making the outer wall of the airbag almost sealed with the inner wall of the extraction hole. This achieves the first-level seal (front and rear sides) of the sealing section of the extraction hole, and simultaneously fixes the position of the extraction pipe 1. Then, grout is injected into the extraction hole area between the forward limiting airbag 2 and the rear limiting airbag 3 through the grouting pipe 5. When grout flows out of the return pipe 6, grouting is stopped. At this time, the outside of the pressure-replenishing airbag 4 is surrounded by grout. Inflate the pressure-replenishing airbag 4 to make it expand, thus increasing the internal pressure of the grout. The pressure is increased, allowing the grout to fill the gaps in the extraction hole. Excess grout and air are discharged through the return pipe 6. When the return pipe 6 stops discharging air, the grouting pipe 5 and the return pipe 6 are closed, and air is continuously pumped into the pressure-replenishing airbag 4 to increase its pressure. This allows the grout to continuously penetrate the coal seam gaps and the gaps between the front limiting airbag 2, the rear limiting airbag 3, and the inner wall of the extraction hole under high pressure, achieving a more effective seal in the extraction hole sealing section. Inflation continues until the upper limit of the safety value of the pressure-replenishing airbag 4 is reached, at which point inflation stops, and this pressure is maintained for a period of time until the grout is completely cured, thus achieving a secondary seal in the extraction hole sealing section. Under this construction method, the use of the pressure-replenishing airbag 4 reduces the amount of sealing material used in the extraction section, effectively reducing grouting time. It is worth noting that by employing primary and secondary sealing, and utilizing the pressure-replenishing airbag 4 to further fill the gaps with grout, the porosity of the sealing section is reduced, effectively improving the sealing effect. Since the front limiting airbag 2 and the rear limiting airbag 3 impede the flow of grout to the areas before and after the extraction hole, it prevents grout from clogging the small holes (vents) on the front end of the extraction pipe 1, and effectively reduces the amount of grout used. This device is more suitable for use when the diameter of the extraction hole is much larger than that of the extraction pipe, effectively reducing the amount of sealing material (grout) used.

[0028] By installing a front limiting airbag 2, a rear limiting airbag 3, a pressure replenishing airbag 4, a grouting pipe 5, and a return pipe 6 on the extraction pipe 1, multi-stage sealing of the gas extraction hole can be achieved, resulting in better sealing performance and effectively reducing the amount of grout used, thus saving grouting time.

[0029] Example 2:

[0030] like Figure 2As shown, a first support pipe 7 is fixedly installed inside the pressure-replenishing airbag 4. The inner diameter of the first support pipe 7 is larger than the outer diameter of the extraction pipe 1. A support frame 8 is fixedly installed between the first support pipe 7 and the extraction pipe 1. The support frame 8 allows grout to enter the gap between the extraction pipe 1 and the first support pipe 7. In use, the grout not only fills the gap between the pressure-replenishing airbag 4 and the extraction hole, but also fills the gap between the extraction pipe 1 and the first support pipe 7, thus completely encapsulating the pressure-replenishing airbag 4. The structural strength of the column structure formed after the grout has solidified is improved, which in turn further improves the structural strength of the sealing section.

[0031] By setting the first support pipe 7, it is convenient to support and fix the pressure-replenishing airbag 4, and it is also beneficial to improve the structural strength of the extraction hole sealing section.

[0032] Example 3:

[0033] like Figure 1-2 As shown, a first inflation / deflation pipe 9 is fixedly installed inside the first support pipe 7, which connects to the pressure replenishing airbag 4. One end of the first inflation / deflation pipe 9 extends outward from the extraction pipe 7 and passes through the rear limiting airbag 3. In use, the first inflation / deflation pipe 9 can be connected to an air pump to inflate the pressure replenishing airbag 4.

[0034] By fixing a first inflation / deflation pipe 9, which connects to the pressure-replenishing airbag 4, inside the first support pipe 7, the inflation / deflation of the pressure-replenishing airbag 4 can be achieved.

[0035] Example 4:

[0036] like Figure 1 and Figure 3 As shown, a second support tube 10 is fixedly installed inside the front limiting airbag 2. The second support tube 10 is fixedly sleeved on the extraction tube 1, and there is no gap between the two. A second inflation / deflation tube 11 that connects to the front limiting airbag 2 is installed on one side of the second support tube 10. The second inflation / deflation tube 11 passes through the inside of the first support tube 7 and then through the rear limiting airbag 3. When in use, air can be inflated into the front limiting airbag 2 through the second inflation / deflation tube 11.

[0037] By setting a second support tube 10 and installing a second inflation / deflation tube 11, the front limiting airbag 2 can be easily supported and inflated / deflated.

[0038] Example 5:

[0039] like Figure 1 and Figure 4As shown, a third support pipe 12 is fixedly installed inside the rear limiting airbag 3. The third support pipe 12 is also fixedly sleeved on the extraction pipe 1, and there is no gap between the two. A third inflation / deflation pipe 13 that connects to the rear limiting airbag 3 is installed on the third support pipe 12. In use, the rear limiting airbag 3 can be inflated or deflated through the third inflation / deflation pipe 13. It is worth noting that valves should be installed on the grouting pipe 5, the return pipe 6, the first inflation / deflation pipe 9, the second inflation / deflation pipe 11, and the third inflation / deflation pipe 3.

[0040] By setting the third support tube 12 and installing the third inflation / deflation tube 13, the rear limiting airbag 3 can be easily supported and inflated / deflated.

[0041] Example 6:

[0042] like Figure 4 As shown, multiple mounting holes 14 are provided along the length of the third support pipe 12. The grouting pipe 5, the return pipe 6, the first air filling and venting pipe 9, and the second air filling and venting pipe 11 pass through the corresponding mounting holes 14 and are sealed with sealing material.

[0043] By providing multiple mounting holes 14 along the length of the third support pipe 12, the installation of the grouting pipe 5, return pipe 6, first air filling and venting pipe 9, and second air filling and venting pipe 11 can be facilitated.

[0044] Working principle: During use, after inserting the extraction pipe 1 into the gas extraction hole of the inclined coal seam at the predetermined depth, inflate the forward limiting airbag 2 and the rear limiting airbag 3. This expansion causes the airbags to press tightly against the inner wall of the extraction hole, creating a near-sealed connection between the outer wall of the airbags and the inner wall of the extraction hole. This achieves the first-level seal (front and rear sides) of the sealing section of the extraction hole, while simultaneously fixing the position of the extraction pipe 1. Then, grout is injected into the extraction hole area between the forward limiting airbag 2 and the rear limiting airbag 3 through the grouting pipe 5. When grout flows out of the return pipe 6, grouting is stopped. At this time, the outer side of the pressure-replenishing airbag 4 is surrounded by grout. Inflate the pressure-replenishing airbag 4 to make it expand, allowing the grout to penetrate further. Increased pressure causes grout to fill the gaps in the extraction hole. Excess grout and air are discharged through the return pipe 6. When the return pipe 6 stops discharging air, the grouting pipe 5 and the return pipe 6 are closed, and air is continuously pumped into the pressure-replenishing airbag 4 to increase its pressure. This allows the grout to continuously penetrate the coal seam gaps and the gaps between the front limiting airbag 2, the rear limiting airbag 3, and the inner wall of the extraction hole under high pressure, achieving a more effective seal in the extraction hole sealing section. Inflation continues until the upper limit of the safety value of the pressure-replenishing airbag 4 is reached, at which point inflation stops and is maintained at this pressure for a period of time until the grout is completely cured, thus achieving a secondary seal in the extraction hole sealing section. Under this construction method, the use of the pressure-replenishing airbag 4 reduces the amount of sealing material used in the extraction section, effectively reducing grouting time. It is worth noting that by using a first- and second-level seal and utilizing the pressure-replenishing airbag 4 to further fill the gaps with grout, the porosity of the sealing section can be reduced, which can effectively improve the sealing effect. Since the front limiting airbag 2 and the rear limiting airbag 3 hinder the flow of grout to the areas before and after the extraction hole, it can prevent the grout from clogging the small holes on the front end of the extraction pipe 1 and can effectively reduce the amount of grout used.

Claims

1. A multi-stage sealing structure for inclined coal seam gas extraction boreholes, characterized in that, include: A sampling pipe (1) is provided, with a front limiting airbag (2) and a rear limiting airbag (3) installed on the sampling pipe (1), and a pressure replenishing airbag (4) installed on the sealing section of the sampling pipe (1). A grouting pipe (5) and a return pipe (6) are installed on the rear limiting airbag (3). One end of the grouting pipe (5) is close to the front limiting airbag (2), and one end of the return pipe (6) is close to the rear limiting airbag (3).

2. The multi-stage sealing structure for inclined coal seam gas extraction boreholes according to claim 1, characterized in that, The first support tube (7) is fixedly installed on the inner side of the pressure-replenishing airbag (4), and a support frame (8) is fixedly installed between the first support tube (7) and the extraction tube (1).

3. The multi-stage sealing structure for inclined coal seam gas extraction boreholes according to claim 2, characterized in that, The first support tube (7) has a first inflation / deflation tube (9) that connects to the pressure-replenishing airbag (4) fixedly installed on its inner side.

4. The multi-stage sealing structure for inclined coal seam gas extraction boreholes according to claim 1, characterized in that, A second support tube (10) is fixedly installed on the inner side of the front limiting airbag (2), and a second inflation / deflation tube (11) connecting the front limiting airbag (2) is installed on one side of the second support tube (10).

5. The multi-stage sealing structure for inclined coal seam gas extraction boreholes according to claim 1, characterized in that, A third support tube (12) is fixedly installed on the inner side of the rear limiting airbag (3), and a third inflation / deflation tube (13) communicating with the rear limiting airbag (3) is installed on the third support tube (12).

6. The multi-stage sealing structure for inclined coal seam gas extraction boreholes according to claim 5, characterized in that, The third support tube (12) has multiple mounting holes (14).

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