Secondary sealing device and method for gas extraction drilling hole

Abstract

The application discloses a secondary hole sealing device for gas extraction drilling, which comprises a main body cylinder, a connecting rod, a slurry filling assembly and a gas bag hole sealing mechanism.

Description

Technical Field

[0001] This invention belongs to the technical field of coal mine borehole sealing equipment, specifically a secondary sealing device and method for gas drainage boreholes. Background Technology

[0002] Currently, the main methods for controlling mine gas include protective layer mining, ventilation, and gas extraction. Among these, gas extraction is the most effective way to control gas. The sealing quality of the extraction boreholes directly affects the effectiveness of mine gas extraction and whether the control measures meet production requirements. Inadequate sealing results in poor extraction efficiency, low gas concentration, and the release of gas into the roadway, damaging the underground working environment and threatening the lives of workers. In existing technologies, common methods for sealing extraction boreholes include polyurethane, cement mortar, or mechanical sealing with expanding capsules. While polyurethane is easy to foam and has high sealing efficiency, it is prone to problems such as incomplete sealing and clogging of the injection pipe. With cement mortar, gas leaks continuously during the injection of cement slurry into the borehole. Before the cement slurry dries and solidifies, the gas inside the borehole creates gaps in the filled cement mortar, causing further gas leakage and poor sealing performance. Mechanical sealing devices with expanding capsules tend to loosen and leak air as the capsule contracts under pressure. Therefore, those skilled in the art have provided a secondary sealing device and method for gas extraction boreholes to address the problems mentioned in the background. Summary of the Invention

[0003] To achieve the above objectives, the present invention provides the following technical solution: a secondary sealing device for gas drainage boreholes, comprising:

[0004] The main cylinder has fastening threads on its outer circumference, and the main cylinder can be screwed into the gas borehole.

[0005] A connecting rod is coaxially and slidably disposed inside the main body cylinder, and a connecting plate is fixed to one end of the connecting rod;

[0006] A slurry filling assembly, sleeved on the connecting rod on the side away from the main cylinder; and

[0007] An airbag sealing mechanism is mounted on the connecting rod and located between the slurry filling assembly and the main cylinder.

[0008] Furthermore, as a preferred embodiment, multiple air guide grooves are symmetrically formed on the circumferential sidewall of the main body cylinder, and a cover plate is embedded and fixed in the air guide groove. Multiple air inlet holes are formed on the cover plate. A guide sleeve is embedded in one side of the main body cylinder, and a sliding cylinder is axially slidably arranged in the guide sleeve. The cross-section of the sliding cylinder and the guide sleeve are both polygonal. The sliding cylinder is provided with air holes. One end of the connecting rod is fixed to the sliding cylinder, and a fixing spring is connected to one side of the sliding cylinder. One end of the fixing spring is connected to the main body cylinder.

[0009] Furthermore, preferably, the slurry filling assembly includes:

[0010] A connecting plate is fixed to one end of the connecting rod;

[0011] An elastic sleeve, one end of which is fitted and fixed to the connecting plate;

[0012] A partition is fixedly disposed in the middle of the elastic sleeve and slidably connected to the connecting rod. The partition divides the elastic sleeve into two cavities on the left and right sides. The cavity on the opposite left is a water storage cavity, and the other cavity is a cement cavity. An intermediate plate is fixed to the other end of the elastic sleeve.

[0013] Fixed tubes are symmetrically distributed on the partition plate. Each fixed tube is transversely connected to the partition plate, and multiple through holes are opened on the side of the fixed tube located in the cement cavity.

[0014] The inner shaft cylinder is embedded and fixed on the intermediate plate;

[0015] The first rubber sleeve is fitted over the connecting rod and is located between the connecting plate and the partition plate;

[0016] The second rubber sleeve is fitted over the connecting rod and is located between the partition and the intermediate plate.

[0017] Furthermore, as a preferred embodiment, the water storage chamber stores water, the cement chamber stores cement, and the elastic sleeve at the cement chamber has multiple micropores on the side near the intermediate plate, and each of the fixed tubes is also provided with a separator.

[0018] Furthermore, as a preferred embodiment, the inner shaft cylinder is fitted with a shaft tube, a spinning disc is mounted on the shaft tube, and a spiral guide groove is formed on the circumferential side wall of the shaft tube. A shaft pin is fixed on the inner shaft cylinder, and the shaft pin is slidably disposed in the spiral guide groove. A top plate is also fixed on the connecting rod. The top plate pushes the shaft tube axially, and drives the shaft tube to rotate synchronously through the shaft pin.

[0019] Furthermore, preferably, the airbag sealing mechanism includes:

[0020] An outer shaft seat is fixed to one side of the inner shaft cylinder in the slurry filling assembly. The connecting rod is slidably connected to the outer shaft seat, and a sealing sleeve is provided between them.

[0021] A shaft plug is fitted and fixed on the connecting rod, and the shaft plug is slidably connected to the inner shaft cylinder;

[0022] All oblique flow holes are formed on the outer shaft seat;

[0023] An airflow guide, circumferentially distributed on the outer shaft seat, is correspondingly connected to the oblique flow hole; and

[0024] An annular air pressure bladder is fitted onto the outer shaft seat and is connected to the airflow guide.

[0025] Furthermore, as a preferred embodiment, the cross-section of the annular airbag has an L-shaped structure.

[0026] Furthermore, as a preferred embodiment, the sealing method of the secondary sealing device for gas extraction boreholes is characterized by comprising the following steps:

[0027] Step 1: Main body installation. In the gas drainage borehole that has been constructed, the elastic sleeve is pushed into the gas drainage borehole. The sliding cylinder is rotated by a polygonal wrench so that the main body cylinder can be screwed into the gas drainage borehole. At this time, the main body cylinder achieves the sealing effect of the coal mine gas drainage borehole.

[0028] Step 2: Airbag sealing. As time goes by, the gas concentration in the borehole increases and flows into the main cylinder through the air guide groove. Then, it enters the sliding cylinder through multiple air holes on the sliding cylinder. The pressure in the sliding cylinder increases and slides axially relative to the main cylinder. The fixed spring is stretched, and the connecting rod moves synchronously. The shaft plug pushes the airflow in the inner shaft cylinder to the annular air pressure bag, so that the annular air pressure bag fully contacts the inner wall of the borehole.

[0029] Step 3: Cement sealing. The pressure inside the sliding cylinder continues to increase. When the connecting rod slides axially, the elastic sleeve is squeezed and expanded. The first rubber sleeve and the second rubber sleeve are squeezed and compressed respectively. At the same time, the water in the water storage cavity squeezes and impacts the partition plate in the fixed pipe and is broken. The water flows into the cement cavity through the through hole. The water and cement mix to form a slurry. The elastic sleeve expands and fits tightly against the inner wall of the borehole.

[0030] Step 4: Flowing and solidification. A small portion of the slurry can overflow through the micropores to the outside of the elastic sleeve under the pressure of the spinning disc. At this time, the slurry fully seals the contact edge between the annular air pressure bag and the inner wall of the borehole.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] In this invention, after the borehole is mechanically sealed by the main cylinder, it can automatically re-seal the borehole as the gas increases, resulting in a better sealing effect. The main components of the slurry filling component and the airbag sealing mechanism can solidify and seal the borehole with a mixture of water and cement, and can also re-seal the borehole with the annular airbag in conjunction with the slurry, resulting in a significant sealing effect. Attached Figure Description

[0033] Figure 1This is a schematic diagram of the structure of the present invention. Figure 1 ;

[0034] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 ;

[0035] Figure 3 This is a schematic diagram of the sliding cylinder in this invention;

[0036] Figure 4 This is a schematic diagram of the slurry filling component in this invention;

[0037] Figure 5 This is a schematic diagram of the structure of the spinning disc in this invention;

[0038] Figure 6 This is a schematic diagram of the structure of the axial tube in this invention;

[0039] Figure 7 This is a schematic diagram of the airbag sealing mechanism in this invention;

[0040] In the diagram: 1. Main cylinder; 11. Connecting plate; 12. Connecting rod; 13. Air guide groove; 14. Sliding cylinder; 15. Guide sleeve; 16. Cover plate; 17. Fixed spring; 2. Airbag sealing mechanism; 21. Outer shaft seat; 22. Shaft plug; 23. Airflow guide; 24. Annular air pressure bladder; 3. Slurry filling assembly; 31. Elastic sleeve; 32. Partition plate; 33. First rubber sleeve; 34. Second rubber sleeve; 35. Intermediate plate; 36. Inner shaft cylinder; 37. Fixed tube; 38. Separator; 4. Shaft tube; 41. Spinning plate; 42. Shaft pin; 43. Top plate. Detailed Implementation

[0041] Please see Figure 1 In this embodiment of the invention, the secondary sealing device for gas drainage boreholes includes:

[0042] The main body cylinder 1 has fastening threads on its outer circumference, and the main body cylinder 1 can be screwed into the gas borehole.

[0043] A connecting rod 12 is coaxially and slidably disposed inside the main body cylinder 1, and a connecting plate is fixed to one end of the connecting rod 12;

[0044] The slurry filling assembly 3 is sleeved on the connecting rod 12 on the side away from the main cylinder 1; and

[0045] The airbag sealing mechanism 2 is mounted on the connecting rod 12 and located between the slurry filling assembly 3 and the main cylinder 1.

[0046] In this embodiment, a plurality of air guide grooves 13 are symmetrically opened on the circumferential sidewall of the main body cylinder 1. A cover plate 16 is embedded and fixed in the air guide groove 13. A plurality of air inlet holes are opened on the cover plate 16. A guide sleeve 15 is embedded in one side of the main body cylinder 1. A sliding cylinder 14 is axially slidably arranged in the guide sleeve 15. The cross-section of the sliding cylinder 14 and the guide sleeve 15 are both polygonal. The sliding cylinder is provided with air holes, so that the sliding cylinder cannot rotate relative to the main body cylinder. One end of the connecting rod 12 is fixed to the sliding cylinder 14, and a fixing spring 17 is connected to one side of the sliding cylinder 14. One end of the fixing spring 17 is connected to the main body cylinder 2. That is to say, when in use, the main body cylinder is screwed into the gas extraction borehole to achieve a mechanical sealing effect. As time goes by, the gas concentration increases and enters the main body cylinder through the cover plate on the air guide groove, and then enters the sliding cylinder through the air holes on the sliding cylinder, so that the sliding cylinder slides axially.

[0047] In a preferred embodiment, the slurry filling component 3 includes:

[0048] The connecting plate 11 is fixed to one end of the connecting rod 12;

[0049] The elastic sleeve 31 has one end fitted and fixed onto the connecting plate 11; it has a high elastic expansion and contraction effect.

[0050] A partition 32 is fixedly disposed in the middle of the elastic sleeve 31 and slidably connected to the connecting rod 12. The partition 32 divides the elastic sleeve 31 into two cavities on the left and right sides. The cavity on the opposite left side is a water storage cavity, and the other cavity is a cement cavity. An intermediate plate 35 is fixed to the other end of the elastic sleeve.

[0051] Fixed tubes 37 are symmetrically distributed on the partition plate 32. Each fixed tube 37 is transversely connected to the partition plate 32, and multiple through holes are opened on the side of the fixed tube 37 located in the cement cavity.

[0052] The inner shaft cylinder 36 is embedded and fixed on the intermediate plate 35;

[0053] The first rubber sleeve 33 is sleeved on the outside of the connecting rod 12 and is located between the connecting plate 12 and the partition plate 32;

[0054] The second rubber sleeve 34 is sleeved on the outside of the connecting rod 12 and is located between the partition plate 32 and the intermediate plate 35. As the connecting rod slides axially, the elastic sleeve is gradually compressed. At the same time, the first rubber sleeve and the second rubber sleeve are also compressed synchronously. The supporting strength of the second rubber sleeve is greater than that of the first rubber sleeve, so that the first rubber sleeve can undergo elastic deformation better than the second rubber sleeve, thereby causing the pressure in the water storage chamber to increase preferentially.

[0055] In this embodiment, the water storage chamber stores water, the cement chamber stores cement, and the elastic sleeve 31 at the cement chamber is provided with multiple micropores on the side near the intermediate plate 35. Each of the fixed tubes 37 is also provided with a separator 38. When the pressure in the water storage chamber increases, the water impacts and squeezes the separator, and can break through the separator, thereby flowing into the cement chamber to form a slurry.

[0056] In this embodiment, the inner shaft cylinder 36 is sleeved with a shaft tube 4, a spinning disc 41 is installed on the shaft tube 4, and a spiral guide groove is formed on the circumferential side wall of the shaft tube 4. A shaft pin 42 is fixed on the inner shaft cylinder 36, and the shaft pin 42 is slidably disposed in the spiral guide groove. A top plate 43 is also fixed on the connecting rod 12. The top plate 43 pushes the shaft tube 4 axially and drives the shaft tube 4 to deflect synchronously through the shaft pin 42. In particular, after water and cement are mixed to form a slurry, the connecting rod slides axially and can push the shaft tube to slide through the top plate. The shaft tube deflects during the sliding, so that the spinning disc can compress the slurry circumferentially, so that a small part of the slurry can overflow through the micropores to the outside of the elastic sleeve and contact the airbag sealing mechanism, thereby achieving the gap sealing effect of the airbag sealing mechanism.

[0057] In this embodiment, the airbag sealing mechanism 2 includes:

[0058] The outer shaft seat 21 is fixed to one side of the inner shaft cylinder 36 in the slurry filling assembly 3. The connecting rod 12 is slidably connected to the outer shaft seat 21, and a sealing sleeve is provided between them.

[0059] A shaft plug 22 is sleeved and fixed on the connecting rod 12, and the shaft plug 22 is slidably connected to the inner shaft cylinder 36;

[0060] All oblique flow holes are formed on the outer shaft seat 21;

[0061] Airflow guides 23 are circumferentially distributed on the outer shaft seat 21, and the airflow guides 23 are correspondingly connected to the oblique flow holes; and

[0062] The annular air pressure bladder 24 is sleeved on the outer shaft seat 21 and is connected to the airflow guide 23.

[0063] In a preferred embodiment, the annular air pressure bladder 24 has an L-shaped cross-section, and the annular air pressure bladder can contact the borehole inner wall before the slurry filling assembly.

[0064] In this embodiment, the sealing method of the secondary sealing device for gas drainage boreholes includes the following steps:

[0065] Step 1: Main body installation. In the gas drainage borehole that has been constructed, the elastic sleeve 31 is pushed into the gas drainage borehole. The sliding cylinder 14 is rotated by the polygonal wrench so that the main body cylinder 1 can be screwed into the gas drainage borehole. At this time, the main body cylinder 1 achieves the sealing effect on the coal mine gas drainage borehole.

[0066] Step 2: Airbag sealing. As time goes by, the gas concentration in the borehole increases and flows into the main body cylinder 1 through the air guide groove 13. Then, it enters the sliding cylinder 14 through multiple air holes on the sliding cylinder 14. The pressure in the sliding cylinder 14 increases and slides axially relative to the main body cylinder 1. The fixed spring 17 is stretched, and the connecting rod 12 moves synchronously. The shaft plug 22 pushes the airflow in the inner shaft cylinder 36 to the annular air pressure bladder 24, so that the annular air pressure bladder 24 fully contacts the inner wall of the borehole.

[0067] Step 3: Cement sealing. The pressure inside the sliding cylinder 14 continues to increase. When the connecting rod 12 slides axially, the elastic sleeve 31 is squeezed and expanded, while the first rubber sleeve 33 and the second rubber sleeve 34 are squeezed and compressed respectively. At the same time, the water in the water storage cavity squeezes and impacts the partition plate 38 in the fixed pipe and is broken. The water flows into the cement cavity through the through hole. The water and cement mix to form a slurry. The elastic sleeve 31 expands and fits tightly against the inner wall of the borehole.

[0068] Step 4: Flowing and solidification. A small portion of the slurry can overflow through the micropores to the outside of the elastic sleeve 31 under the pressure of the spinning disc 41. At this time, the slurry fully seals the contact edge between the annular air pressure bladder 24 and the inner wall of the borehole.

[0069] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A secondary sealing device for gas drainage boreholes, characterized in that: include: The main body cylinder (1) has fastening threads on its outer circumference, and the main body cylinder (1) can be screwed into the gas extraction borehole. A connecting rod (12) is coaxially slidably disposed inside the main body cylinder (1), and a connecting plate is fixed at one end of the connecting rod (12); The slurry filling assembly (3) is sleeved on the connecting rod (12) on the side away from the main cylinder (1); An airbag sealing mechanism (2) is provided on the connecting rod (12) and located between the slurry filling assembly (3) and the main cylinder (1); The slurry filling component (3) includes: A connecting plate (11) is fixed to one end of the connecting rod (12); An elastic sleeve (31) is fitted and fixed at one end to the connecting plate (11); A partition (32) is fixedly disposed in the middle of the elastic sleeve (31) and slidably connected to the connecting rod (12). The partition (32) divides the elastic sleeve (31) into two cavities on the left and right sides. The cavity on the left side is a water storage cavity, and the other cavity is a cement cavity. An intermediate plate (35) is fixed to the other end of the elastic sleeve. Fixed tubes (37) are symmetrically distributed on the partition plate (32). Each fixed tube (37) is transversely connected to the partition plate (32), and multiple through holes are opened on one side of the cement cavity on the fixed tube (37). The inner shaft cylinder (36) is embedded and fixed on the intermediate plate (35); The first rubber sleeve (33) is fitted over the connecting rod (12) and is located between the connecting plate (11) and the partition plate (32); The second rubber sleeve (34) is fitted over the connecting rod (12) and is located between the partition (32) and the intermediate plate (35); The inner shaft cylinder (36) is sleeved with a shaft tube (4), a spinning disc (41) is installed on the shaft tube (4), and a spiral guide groove is opened on the circumferential side wall of the shaft tube (4). A shaft pin (42) is fixed on the inner shaft cylinder (36), and the shaft pin (42) is slidably arranged in the spiral guide groove. A top plate (43) is also fixed on the connecting rod (12). The top plate (43) pushes the shaft tube (4) axially and drives the shaft tube (4) to rotate synchronously through the shaft pin (42). The airbag sealing mechanism (2) includes: The outer shaft seat (21) is fixed to one side of the inner shaft cylinder (36) in the slurry filling assembly (3). The connecting rod (12) is slidably connected to the outer shaft seat (21), and a sealing sleeve is provided between them. A shaft plug (22) is sleeved and fixed on the connecting rod (12), and the shaft plug (22) is slidably connected to the inner shaft cylinder (36); All oblique flow holes are opened on the outer shaft seat (21); An airflow guide (23) is circumferentially distributed on the outer shaft seat (21), and the airflow guide (23) is correspondingly connected to the oblique flow hole; An annular air pressure bladder (24) is fitted onto the outer shaft seat (21) and is connected to the airflow guide (23).

2. The secondary sealing device for gas extraction boreholes according to claim 1, characterized in that: Multiple air guide grooves (13) are symmetrically opened on the circumferential sidewall of the main body cylinder (1). A cover plate (16) is embedded and fixed in the air guide groove (13). Multiple air inlets are opened on the cover plate (16). A guide sleeve (15) is embedded in one side of the main body cylinder (1). A sliding cylinder (14) is axially slidably arranged in the guide sleeve (15). The cross-section of the sliding cylinder (14) and the guide sleeve (15) are both polygonal. Air holes are provided on the sliding cylinder (14). One end of the connecting rod (12) is fixed to the sliding cylinder (14), and a fixing spring (17) is connected to one side of the sliding cylinder (14). One end of the fixing spring (17) is connected to the main body cylinder (1).

3. The secondary sealing device for gas extraction boreholes according to claim 1, characterized in that: The water storage chamber stores water, the cement chamber stores cement, and the elastic sleeve (31) at the cement chamber has multiple micropores on the side near the intermediate plate (35), and each of the fixed tubes (37) is also provided with a partition plate (38).

4. The secondary sealing device for gas extraction boreholes according to claim 1, characterized in that: The cross-section of the annular air pressure bladder (24) is L-shaped.

5. The sealing method of the secondary sealing device for gas drainage boreholes according to any one of claims 1 to 4, characterized in that: Includes the following steps: Step 1: Main body installation. In the gas extraction borehole that has been constructed, the elastic sleeve (31) is pushed into the gas extraction borehole. The sliding cylinder (14) is rotated by the polygonal wrench so that the main body cylinder (1) can be screwed into the gas extraction borehole. At this time, the main body cylinder (1) achieves the sealing effect on the gas extraction borehole. Step 2: Airbag sealing. As time goes by, the gas concentration in the borehole increases continuously and flows into the main body cylinder (1) through the air guide groove (13). Then, it enters the sliding cylinder (14) through multiple air holes on the sliding cylinder (14). The pressure in the sliding cylinder (14) increases and slides axially relative to the main body cylinder (1). The fixed spring (17) is stretched. At this time, the connecting rod (12) moves synchronously. The shaft plug (22) pushes the airflow in the inner shaft cylinder (36) to the annular air pressure bladder (24), so that the annular air pressure bladder (24) fully contacts the inner wall of the borehole. Step 3: Cement sealing, the pressure inside the sliding cylinder (14) continues to increase, and when the connecting rod (12) slides axially, the elastic sleeve (31) is squeezed and expanded, while the first rubber sleeve (33) and the second rubber sleeve (34) are squeezed and compressed respectively. At the same time, the water in the water storage cavity squeezes and impacts the partition plate (38) in the fixed pipe and is broken. The water flows into the cement cavity through the through hole, and the water and cement mix to form a slurry. The elastic sleeve (31) expands and fits tightly against the inner wall of the borehole. Step 4: Flow solidification. A small portion of the slurry can overflow through the micropores to the outside of the elastic sleeve (31) under the pressure of the spinning disc (41). At this time, the slurry fully seals the contact edge between the annular air pressure bladder (24) and the inner wall of the borehole.

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