A gas pressure safety monitoring device for deep coalbed methane mining

Abstract

The present invention discloses a gas pressure safety monitoring device for deep coalbed methane mining, comprising a shell, an extraction pipe, and a connecting flange. The shell is sleeved outside the extraction pipe, and the upper and lower parts of the shells are fixed to the multiple extraction pipes through connecting flanges. A hollow bracket is fixed below the shell, and a rubber ring is provided between the bracket and the bottom of the shell. A gas pressure sensor connected to the extraction pipe is provided above the shell. Compared with the prior art, the present invention can realize accurate monitoring of the changes in coalbed methane pressure at different depths, and provide more accurate coalbed methane mining data and safety control basis.

Description

Technical Field

[0001] The invention relates to the technical field of coal bed gas mining, in particular to a gas pressure safety monitoring device for deep coal bed gas mining. Background Art

[0002] In the process of deep coalbed methane mining, air pressure monitoring is crucial for safe production. However, the current coalbed methane mining air pressure monitoring devices have some shortcomings, which limit their accuracy and applicability. Since coalbed methane mining is often carried out underground, the surrounding environment may have complex geological structures and hydrological conditions. These factors will affect the change of air pressure and may interfere with the accuracy of the monitoring device. In addition, in deep coalbed methane mining, there may be differences in coalbed methane pressure at different depths. However, existing devices can often only monitor the average air pressure of the entire coalbed methane extraction area, and the air pressure in the deep coal seam gap is often different from that in the shallow part. This leads to a lack of accurate reference basis when formulating safety control measures, increasing the risk of accidents.

[0003] In summary, the existing deep coalbed methane mining gas pressure safety monitoring device has the problems of being easily disturbed by the external environment and being unable to monitor gas pressures in different ranges. Therefore, it is necessary to provide a deep coalbed methane mining gas pressure safety monitoring device to improve the accuracy and reliability of gas pressure monitoring, while achieving accurate monitoring of coalbed methane pressure changes at different depths, and ensuring good sealing performance of the wellbore, providing more reliable technical support for the safety control of deep coalbed methane mining. Summary of the invention

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a deep coalbed methane mining gas pressure safety monitoring device, comprising a shell, an extraction pipe, and a connecting flange, wherein the shell is sleeved outside the extraction pipe, and the multiple shells are fixed to multiple extraction pipes through connecting flanges at the top and bottom, a hollow bracket is fixed under the shell, a rubber ring is provided between the bracket and the bottom of the shell, and an air pressure sensor connected to the extraction pipe is provided above the shell.

[0005] Furthermore, as a preference, an expansion sleeve is slidably provided in the shell, and the expansion sleeve can separate the gap between the shell and the extraction tube into a closed upper cavity and a lower cavity, and a conical guide cone with a diameter decreasing downward is fixed to the lower end of the expansion sleeve, and the outer wall of the guide cone is embedded in the gap between the rubber ring and the extraction tube.

[0006] Further, as a preference, the extraction tube is provided with an upper outer hole and a lower outer hole at positions corresponding to the upper cavity and the lower cavity respectively, and the extraction tube is slidably provided with a movable sleeve on the inner wall at a position inside the shell, and the movable sleeve is provided with an upper inner hole and a lower inner hole at positions corresponding to the upper cavity and the lower cavity respectively.

[0007] Further, as a preference, a movable ring is fixed to the upper end of the movable sleeve, an electromagnetic ring is fixed in the shell at a certain distance below the movable ring, and a spring is provided between the movable ring and the electromagnetic ring.

[0008] Further, as a preference, an upper balancing hole and a lower balancing hole are respectively provided on the side wall of the shell at positions corresponding to the upper cavity and the lower cavity, and the upper balancing hole and the lower balancing hole are respectively connected to the upper cavity and the lower cavity.

[0009] Furthermore, preferably, a vertical movable rod is slidably embedded in the positions corresponding to the upper balancing hole and the lower balancing hole in the shell, one end of the movable rod is fixed to the movable ring, and when the upper outer hole is aligned with the upper inner hole, the movable rod closes the upper balancing hole, and when the lower outer hole is aligned with the lower inner hole, the movable rod closes the lower balancing hole.

[0010] Furthermore, as a preference, a circle of grooves is provided in the middle of the outer walls of the upper cavity and the lower cavity, and a through hole is provided in the groove that penetrates into the corresponding upper cavity or the lower cavity.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] Provide accurate coalbed methane pressure monitoring: Through the connection of multiple shells and extraction pipes, and the installation of air pressure sensors, the device can independently monitor the coalbed methane extraction area at each depth. This can more accurately understand the changes in air pressure at different depths, provide accurate coalbed methane mining data and safety control basis, prevent coalbed methane leakage and interference from the external environment, improve the safety of coalbed methane mining, and timely grasp the changes in coalbed methane pressure. It is helpful to prevent and control dangerous situations such as coalbed methane outbursts and gushers, providing an important basis for safe production.

[0013] Flexible adjustment of the connection between the extraction tube and the cavity: Through the design of the movable sleeve and the movable rod, the connection state between the extraction tube and the upper cavity or the lower cavity can be controlled. In this way, the space size of the upper and lower cavities can be adjusted as needed, and the negative pressure in the extraction tube drives the movement of the guide cone to provide power for the change of the rubber ring, ensuring that the rubber ring can withstand greater pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the structure of a gas pressure safety monitoring device for deep coalbed methane mining;

[0015] Figure 2 It is a schematic diagram of the structure of a half-section inside the shell;

[0016] Figure 3 It is a schematic diagram enlarged at point A;

[0017] In the figure: 1. shell; 2. extraction tube; 21. upper outer hole; 22. lower outer hole; 3. connecting flange; 4. rubber ring; 5. air pressure sensor; 6. bracket; 7. expansion sleeve; 71. upper cavity; 72. lower cavity; 73. groove; 74. through hole; 8. guide cone; 9. movable sleeve; 91. upper inner hole; 92. lower inner hole; 10. movable ring; 11. electromagnetic ring; 12. spring; 13. upper balance hole; 14. lower balance hole; 15. movable rod. DETAILED DESCRIPTION

[0018] See also Figure 1 In an embodiment of the present invention, a deep coalbed methane mining gas pressure safety monitoring device includes a shell 1, an extraction pipe 2, and a connecting flange 3. The shell 1 is sleeved outside the extraction pipe 2, and multiple shells 1 are fixed to the multiple extraction pipes 2 through connecting flanges 3 at the top and bottom. A hollow bracket 6 is fixed below the shell 1, and a rubber ring 4 is provided between the bracket 6 and the bottom of the shell 1. A pressure sensor 5 connected to the extraction pipe 2 is provided above the shell 1.

[0019] See also Figure 2 In this embodiment, an expansion sleeve 7 is slidably provided in the shell 1, and the expansion sleeve 7 can separate the gap between the shell 1 and the extraction pipe 2 into a closed upper cavity 71 and a lower cavity 72, and a tapered guide cone 8 with a diameter decreasing downward is fixed to the lower end of the expansion sleeve 7, and the outer wall of the guide cone 8 is embedded in the gap between the rubber ring 4 and the extraction pipe 2. In other words, by sliding the expansion sleeve 7 downward, the guide cone 8 can open the rubber ring 4, so that the diameter of the rubber ring 4 becomes larger to seal the wellbore. At this time, the data monitored by the air pressure sensor 5 is the coalbed methane pressure below the rubber ring 4. The coalbed methane extraction area of ​​each section depth can be detected independently. In this way, the air pressure changes at different depths can be understood more accurately, providing more accurate coalbed methane mining data and safety control basis.

[0020] In this embodiment, the extraction pipe 2 is provided with an upper outer hole 21 and a lower outer hole 22 at positions corresponding to the upper cavity 71 and the lower cavity 72, respectively. The extraction pipe 2 is provided with a movable sleeve 9 on its inner wall in a position in the shell 1, and the movable sleeve 9 is provided with an upper inner hole 91 and a lower inner hole 92 at positions corresponding to the upper cavity 71 and the lower cavity 72, respectively. When the upper outer hole 21 is aligned with the upper inner hole 91, the lower outer hole 22 is staggered with the lower inner hole 92, and when the upper outer hole 21 is staggered with the upper inner hole 91, the lower outer hole 22 is aligned with the lower inner hole 92, that is, the upper cavity 71 or the lower cavity 72 can be connected with the extraction pipe 2 respectively, so that the space of the corresponding upper cavity 71 or the lower cavity 72 is reduced by the negative pressure of the extraction pipe 2, and then the guide cone 8 is pushed to slide up and down, so as to achieve the purpose of using the pressure of the extracted coalbed methane in the extraction pipe 2 to provide power for the change of the rubber ring 4, and ensure that the rubber ring 4 can withstand a large pressure.

[0021] In this embodiment, a movable ring 10 is fixed to the upper end of the movable sleeve 9, an electromagnetic ring 11 is fixed in the housing 1 at a certain distance below the movable ring 10, and a spring 12 is provided between the movable ring 10 and the electromagnetic ring 11. The spring 12 provides elastic force to move the movable sleeve 9 downward, and the electromagnetic ring 11 can absorb the movable ring 10 to move upward when powered on, that is, the up and down movement of the movable sleeve 9 can be controlled by turning the electromagnetic ring 11 on and off, thereby controlling the connection between the extraction tube 2 and the upper cavity 71 or the lower cavity 72.

[0022] In this embodiment, an upper balancing hole 13 and a lower balancing hole 14 are respectively provided at positions of the side wall of the shell 1 corresponding to the upper cavity 71 and the lower cavity 72 , and the upper balancing hole 13 and the lower balancing hole 14 are respectively connected to the upper cavity 71 and the lower cavity 72 .

[0023] In this embodiment, a vertical movable rod 15 is slidably embedded in the position corresponding to the upper balance hole 13 and the lower balance hole 14 in the shell 1, and one end of the movable rod 15 is fixed to the movable ring 10, and when the upper outer hole 21 is aligned with the upper inner hole 91, the movable rod 15 closes the upper balance hole 13, and when the lower outer hole 22 is aligned with the lower inner hole 92, the movable rod 15 closes the lower balance hole 14. In other words, when the extraction tube 2 is connected to the upper cavity 71, the upper cavity 71 is sealed from the outside, and the lower cavity 72 is balanced with the outside air pressure. At this time, the air pressure of the upper cavity 71 is less than the air pressure of the lower cavity 72, so that the expansion sleeve 7 moves up. Similarly, when the extraction tube 2 is connected to the lower cavity 72, the expansion sleeve 7 moves down.

[0024] See also Figure 3 In this embodiment, a circle of grooves 73 are provided in the middle of the outer walls of the upper cavity 71 and the lower cavity 72, and a through hole 74 is provided at the groove 73, which penetrates into the corresponding upper cavity 71 or the lower cavity 72. In other words, as long as the movable rod 15 does not seal the upper balance hole 13 or the lower balance hole 14, the through hole 74 can always communicate with the upper balance hole 13 or the lower balance hole 14 through the groove 73 when the expansion sleeve 7 slides up and down.

[0025] During the specific implementation, the deep coalbed methane mining gas pressure safety monitoring device is assembled, including components such as a shell, an extraction pipe, and a connecting flange. The shell is sleeved outside the extraction pipe, and multiple shells are fixed to multiple extraction pipes through connecting flanges; a hollow bracket is fixed under the shell, and a rubber ring is placed between the bracket and the bottom of the shell;

[0026] By controlling the on and off of the electromagnetic ring, the up and down movement of the movable sleeve can be controlled, thereby controlling the connection between the extraction tube and the upper cavity or the lower cavity, and when the upper outer hole is aligned with the upper inner hole, the movable rod closes the upper balance hole; when the lower outer hole is aligned with the lower inner hole, the movable rod closes the lower balance hole, that is, when the extraction tube is connected to the upper cavity, the upper cavity is sealed from the outside, while the lower cavity is balanced with the outside air pressure. At this time, the air pressure in the upper cavity is less than the air pressure in the lower cavity, so that the expansion sleeve moves up, conversely, when the extraction tube is connected to the lower cavity, the expansion sleeve moves down;

[0027] When the expansion sleeve slides downward, the guide cone expands the rubber ring, making the diameter of the rubber ring larger, thereby achieving sealing of the wellbore. In this way, the air pressure sensor can monitor the coalbed methane pressure intensity below the rubber ring, realize independent monitoring of the coalbed methane extraction area at each depth, and use the pressure change of the extracted coalbed methane in the extraction pipe to provide power, ensuring that the rubber ring can withstand greater pressure.

[0028] The above is the method of using the deep coalbed methane mining gas pressure safety monitoring device of the present invention. Through this device, accurate monitoring of coalbed methane pressure changes at different depths can be achieved, providing more accurate coalbed methane mining data and safety control basis. It is only a preferred specific implementation of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention, according to the technical solution and its inventive concept of the present invention, shall be covered within the protection scope of the present invention.

Claims

1. A gas pressure safety monitoring device for deep coalbed methane mining, comprising a housing (1), an extraction pipe (2), and a connecting flange (3), characterized in that: The shell (1) is sleeved outside the extraction tube (2), and the multiple shells (1) are fixed to the multiple extraction tubes (2) via connecting flanges (3) at the top and bottom. A hollow bracket (6) is fixed below the shell (1), and a rubber ring (4) is provided between the bracket (6) and the bottom of the shell (1). An air pressure sensor (5) connected to the extraction tube (2) is provided above the shell (1); An expansion sleeve (7) is slidably provided in the shell (1), and the expansion sleeve (7) is capable of dividing the gap between the shell (1) and the extraction tube (2) into a sealed upper cavity (71) and a lower cavity (72), and a tapered guide cone (8) with a diameter decreasing downward is fixed to the lower end of the expansion sleeve (7), and the outer wall of the guide cone (8) is embedded in the gap between the rubber ring (4) and the extraction tube (2); The extraction tube (2) is provided with an upper outer hole (21) and a lower outer hole (22) at positions corresponding to the upper cavity (71) and the lower cavity (72), respectively; a movable sleeve (9) is slidably provided on the inner wall of the extraction tube (2) at a position inside the shell (1); and the movable sleeve (9) is provided with an upper inner hole (91) and a lower inner hole (92) at positions corresponding to the upper cavity (71) and the lower cavity (72), respectively; A movable ring (10) is fixed to the upper end of the movable sleeve (9), an electromagnetic ring (11) is fixed in the housing (1) at a certain distance below the movable ring (10), and a spring (12) is provided between the movable ring (10) and the electromagnetic ring (11).

2. A deep coalbed methane mining gas pressure safety monitoring device according to claim 1, characterized in that: An upper balancing hole (13) and a lower balancing hole (14) are respectively provided on the side wall of the shell (1) at positions corresponding to the upper cavity (71) and the lower cavity (72); the upper balancing hole (13) and the lower balancing hole (14) are respectively connected to the upper cavity (71) and the lower cavity (72).

3. A deep coalbed methane mining gas pressure safety monitoring device according to claim 2, characterized in that: A vertical movable rod (15) is slidably embedded in the housing (1) at positions corresponding to the upper balancing hole (13) and the lower balancing hole (14); one end of the movable rod (15) is fixed to the movable ring (10); and when the upper outer hole (21) is aligned with the upper inner hole (91), the movable rod (15) closes the upper balancing hole (13); and when the lower outer hole (22) is aligned with the lower inner hole (92), the movable rod (15) closes the lower balancing hole (14).

4. A deep coalbed methane mining gas pressure safety monitoring device according to claim 3, characterized in that: A circle of grooves (73) are provided in the middle of the outer walls of the upper cavity (71) and the lower cavity (72), and a through hole (74) is provided in the groove (73) and penetrates into the corresponding upper cavity (71) or lower cavity (72).

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