Method for repairing gas extraction borehole in soft coal seam based on pressurization transmission impact energy

Abstract

The present application relates to a kind of soft coal seam gas extraction borehole repair method based on pressure transmission impact energy, belong to coal mine safety field, solve the problem that the effect of gas extraction is influenced by the plugging of borehole caused by conventional collapse in the process of gas extraction in soft low permeability coal seam;Through the connection of underground mine pressure wind source and pressure booster, so that the impact inclined block is in contact with the trigger latch, the bottom of the trigger latch is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact spring, and the impact spring is contacted with the impact

Description

Technical Field

[0001] This invention belongs to the field of coal mine safety and relates to a method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy. Background Technology

[0002] Methane gas is one of the main threats to mine safety. It is a flammable gas primarily composed of methane, existing in coal seams or surrounding rock in both adsorbed and free forms. Currently, my country's coal industry generally employs a combination of protective layer mining and gas drainage to manage mine gas hazards. However, due to the relatively poor geological conditions of coal seams in my country, with most seams being soft and low-permeability, boreholes are prone to collapse during gas drainage. Borehole collapse blocks gas flow channels, thus reducing the efficiency of mine gas control. Therefore, addressing the problem of easy borehole collapse in soft coal seams and researching a suitable technology for efficient borehole repair to ensure the continuous operation of gas drainage is a current hot topic among coal mine safety scientists. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy, which solves the problem of low gas drainage efficiency caused by the collapse of gas drainage boreholes in soft coal seams, thereby effectively ensuring the effectiveness of mine gas disaster control, further ensuring the continuous safe production of coal, and effectively ensuring the personal safety of underground workers.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy includes the following steps:

[0006] S1: Connect the impact repair device to the PE pipe through the first flange, and send the impact repair device to the location where the gas drainage borehole has collapsed; connect the PE pipe to the limiting pipe through the second flange. During the process of sending the impact repair device in, the limiting pawl set on the wall of the limiting pipe can contact the inner wall of the drainage pipe under the action of the supporting spring, and can restrict the impact repair device and the PE pipe from moving towards the gas drainage borehole opening; then connect the limiting pipe to the gas transmission pipe through the third flange; connect the gas transmission pipe to the compressed air source in the coal mine.

[0007] S2: Open the compressed air source in the coal mine to allow high-pressure gas to enter the gas delivery pipe. The gas is pushed by the hose to move the booster input end toward the bottom of the gas drainage borehole. Then, its inclined surface contacts the booster roller, causing the booster output end to also move toward the bottom of the gas drainage borehole. Finally, the impact block hits the inclined surface at the top of the trigger pin. Then, under this action, the trigger pin moves toward the axis of the impact outer pipe, which finally causes the spring limit block to move downward. Thus, the impact cone and impact cylinder impact the coal at the collapse site under the action of the impact spring, causing the coal at the collapse site to scatter.

[0008] S3: Disconnect the gas delivery pipe from the underground compressed air source in the coal mine, drag the reset traction rope to compress the impact spring, causing the spring plate limit block to be in the trigger limit port, thus constraining the movement of the impact cone and impact cylinder in the axial direction of the gas drainage borehole; pull the drag rope set on the limit pawl to move the impact repair device, PE pipe and limit pipe toward the gas drainage borehole opening; then remove the quick connector on the PE pipe, add a new PE pipe and reconnect the quick connector, repeat S1~S2 until there is no obstruction in the gas drainage borehole when the impact repair device connected to the PE pipe is input, indicating that the coal body at the collapse site has been completely impacted and scattered.

[0009] S4: Then pull the tow rope to remove the impact repair device, PE pipe, and limit pipe, connect the extraction pipe to the underground gas extraction pipeline of the coal mine, and continue the gas extraction operation.

[0010] Further, before step S1, a gas drainage borehole is first constructed in the coal seam using appropriate drilling equipment. After sealing the borehole, a drainage pipe is inserted and connected to the underground gas drainage pipeline of the coal mine, so that the gas drainage borehole and the underground gas drainage pipeline network are connected for drainage. Then, the gas concentration and amount of gas extracted from the gas drainage borehole are observed daily. If the gas concentration and amount of gas extracted from the borehole are found to be close to 0, and the gas concentration and amount of gas extracted from adjacent boreholes are within the normal range, it is determined that the borehole has collapsed. At this time, the connection between the gas drainage borehole drainage pipe and the underground gas drainage pipeline of the coal mine is removed, and step S1 is executed.

[0011] Furthermore, the impact repair device includes an impact cone, an impact outer tube, an impact cylinder, an impact spring, an impact spring sheet, a trigger chamber, and a pressure booster. The impact cylinder is disposed inside the impact outer tube, with one end connected to the impact cone. The impact spring connects the impact outer tube and the impact cylinder. An impact spring sheet is provided on one side of the impact cylinder, applying force to the inner wall of the impact outer tube. A spring sheet limiting block is provided at the end of the impact spring sheet. A trigger limiting port, cooperating with the spring sheet limiting block, is provided on the wall of the impact outer tube. A trigger chamber is provided outside the trigger limiting port, and the trigger chamber contains a mechanism for ejecting the spring sheet limiting block. The outer wall of the impact tube is equipped with a booster for activating the trigger pin. The booster includes a support base and a booster housing. Inside the booster housing are a booster input end, a booster roller, a booster output end, and an impact inclined block. The booster input end is connected to the compressed air source in the coal mine. The booster input end, booster roller, booster output end, and impact inclined block are connected in sequence. The impact inclined block is pushed out by compressed air, thereby pressing the trigger pin and pushing out the spring limit block, so that the impact cylinder pops out under the action of the impact spring, and the impact cone impacts the collapsed coal body.

[0012] Furthermore, the tail end of the impact cylinder is provided with a reset traction rope, which is used to pull the impact cylinder back so that the spring limit block is embedded in the trigger limit port, thereby resetting the impact cylinder.

[0013] Furthermore, a limiting pawl is hinged to the wall of the limiting tube, and a support spring is also included. One end of the support spring is connected to the limiting tube, and the other end is connected to the limiting pawl. A drag rope is connected to the limiting pawl.

[0014] Furthermore, the outer impact tube is provided with an impact limiting port, which is used to limit the displacement of the impact cone and impact cylinder when they impact the coal body at the collapse site, and to prevent the impact cylinder from popping out.

[0015] Furthermore, the booster input end of the booster is provided with an inclined surface at an angle of A, and the booster output end is provided with an inclined surface at an angle of B. The pressure from the underground compressed air source in the coal mine acting on the booster input end can be transmitted to the impact block at the tail of the booster output end through the inclined surface of the booster input end, the roller, and the inclined surface at the end of the booster output end. The force transmission relationship is as follows:

[0016] F2 = F1 × tan(B) / tan(A)

[0017] Where A is the slope angle at the tail of the boost input terminal, and B is the slope angle at the end of the boost output terminal, where A <B。

[0018] Furthermore, if A = 15° and B = 75°, then F2 = 14F1, thus increasing the gas pressure of the underground compressed air source in the coal mine by 14 times through the action of the booster.

[0019] The beneficial effects of this invention are as follows:

[0020] This invention proposes a method for repairing boreholes in soft coal seams for gas drainage based on pressurized transmission of impact energy. This method solves the problem of borehole blockage caused by conventional borehole collapse during gas drainage in soft, low-permeability coal seams, which negatively impacts gas drainage efficiency. By connecting an underground compressed air source to a booster, the impact block contacts a trigger pin, pushing the trigger pin so that its bottom cone contacts an impact spring. This causes the spring's limiting block to disengage from the trigger limiting port, allowing the impact cone and impact cylinder to impact the collapsed coal under the action of an impact spring until the coal scatters. Compared with previous gas drainage methods, this method for repairing boreholes in soft coal seams based on pressurized transmission of impact energy has the following advantages:

[0021] (1) The unique method of repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy in this invention does not require the construction of new boreholes and will not damage the sealing structure of gas drainage boreholes. It uses underground compressed air source in coal mines as power to impact the coal body at the collapse site, thereby repairing the blocked gas drainage boreholes, which has extremely significant technical benefits.

[0022] (2) The method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy provided by the present invention uses a combination of limiting pawls and support springs to constrain the impact repair device and PE pipe to move toward the gas drainage borehole opening during operation, effectively ensuring the safety of operators and the repair effect of the drainage borehole; and the limiting pipe can be retrieved and reused multiple times by pulling the tow rope, which has extremely significant economic benefits.

[0023] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0024] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0025] Figure 1 This diagram illustrates the apparatus used in a method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy.

[0026] Reference numerals: 1. Impact cone; 2. Impact outer tube; 21. Trigger limiting port; 3. Impact cylinder; 31. Fixing pin; 4. Impact spring; 5. Impact spring sheet; 51. Spring sheet limiting block; 6. Trigger chamber; 61. Trigger pin; 62. Reset spring; 7. Intensifier; 71. Support base; 72. Intensifier housing; 73. Intensifier input end; 74. Intensifier roller; 75. Intensifier output end; 76. Impact inclined block; 8. Hose; 9. Reset traction rope; 10. Limiting tube; 11. Limiting pawl; 12. Support spring; 13. Drag rope. Detailed Implementation

[0027] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0028] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0029] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0030] Please see Figure 1This invention provides a method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy. The repair is performed using an impact repair device, which includes an impact cone 1, an impact outer tube 2, an impact cylinder 3, an impact spring 4, an impact spring 5, a trigger chamber 6, and a pressure booster 7. The impact cylinder 3 is located inside the impact outer tube 2, with one end connected to the impact cone 1. The impact spring 4 connects the impact outer tube 2 and the impact cylinder 3. One side of the impact cylinder 3 is equipped with an impact spring 5, which applies force to the inner wall of the impact outer tube 2, via a fixing pin 31. The end of the impact spring 5 is equipped with a spring limiting block 51. The wall of the impact outer tube 2 has a trigger limiting port 21 that cooperates with the spring limiting block 51. A trigger chamber 6 is located outside the trigger limiting port 21. The device includes a trigger pin 61 and a return spring 62 for ejecting the spring clip limiting block 51. A booster 7 for activating the trigger pin is located on the outer wall of the impact tube. The booster 7 includes a support base 71 and a booster housing 72. Inside the booster housing 72 are a booster input end 73, a booster roller 74, a booster output end 75, and an impact inclined block 76. The booster input end 73 is connected to the underground compressed air source via a hose 8. The booster input end 73, booster roller 74, booster output end 75, and impact inclined block 76 are connected sequentially. Compressed air ejects the impact inclined block 76, thereby pressing the trigger pin 61 and ejecting the spring clip limiting block 51. This causes the impact cylinder 3 to spring out under the action of the impact spring 4, impacting the collapsed coal mass using the impact cone 1. A return traction rope 9 is located at the tail end of the impact cylinder 3 to pull it back, causing the spring clip limiting block 51 to engage with the trigger limiting port 21, thus resetting the impact cylinder 3. A limiting pawl 11 is hinged to the wall of the limiting tube 10, and a support spring 12 is also included. One end of the support spring 12 is connected to the limiting tube 10, and the other end is connected to the limiting pawl 11. A drag rope 13 is connected to the limiting pawl 11. An impact limiting port 22 is provided on the impact outer tube 2 to limit the displacement of the impact cone 1 and the impact cylinder 3 when they impact the coal body at the collapse site, and to prevent the impact cylinder 3 from popping out. The booster input end 73 is connected to the underground compressed air source in the coal mine, and can transmit the pressure of the underground compressed air source to the tail of the booster input end. An inclined surface with an inclination angle of 15° is provided at the tail of the booster input end. The end of the booster output end 75 is also an inclined surface with an inclination angle of 75°. The pressure from the underground compressed air source acting on the booster input end 73 can be transmitted through the inclined surface of the booster input end 73, the booster roller 74, and the inclined surface at the end of the booster output end 75 to the impact block 76 at the tail of the booster output end 75. The force transmission relationship is as follows:

[0031] F2 = F1 × tan(B) / tan(A)

[0032] A: Incline angle of the ramp at the tail of the boost input terminal 73. B: Incline angle of the ramp at the end of the boost output terminal 75.

[0033] A = 15°; B = 75°, then F2 = 14F1

[0034] It can be seen that the gas pressure of the underground compressed air source in the coal mine is increased by 14 times through the action of the booster 7.

[0035] This method includes the following steps:

[0036] S1: Using appropriate drilling equipment, construct a gas drainage borehole within the coal seam. After sealing the borehole, insert a drainage pipe and connect it to the underground gas drainage pipeline, thus connecting the borehole to the underground gas drainage network. Then, monitor the gas concentration and extraction volume from the borehole daily. If the gas concentration and extraction volume of the borehole approach zero, and the gas concentration and extraction volume of adjacent boreholes are within the normal range, it can be determined that the borehole has collapsed. In this case, disconnect the gas drainage pipe from the underground gas drainage pipeline.

[0037] S2: Then, the impact repair device is connected to the PE pipe through the first flange, and the impact repair device is sent to the location where the gas drainage borehole has collapsed; the PE pipe is connected to the limiting pipe through the second flange. During the process of sending the impact repair device, the limiting pawl set on the wall of the limiting pipe can contact the inner wall of the drainage pipe under the action of the supporting spring, and can restrict the impact repair device and the PE pipe from moving towards the gas drainage borehole opening; then the limiting pipe is connected to the gas transmission pipe through the third flange; the gas transmission pipe is connected to the compressed air source in the coal mine.

[0038] S3: Then, the compressed air source in the coal mine is turned on to allow high-pressure gas to enter the gas delivery pipe. Then, through the hose, the booster input end is pushed towards the bottom of the gas drainage borehole, and its inclined surface contacts the booster roller, so that the booster output end also moves towards the bottom of the gas drainage borehole. Finally, the impact block hits the inclined surface at the top of the trigger pin. Then, under this action, the trigger pin moves towards the axis of the impact surface, and finally the spring limit block moves downward. Thus, the impact cone and impact cylinder impact the coal body at the collapse site under the action of the impact spring, so that the coal body at the collapse site scatters.

[0039] S4: Then, disconnect the gas delivery pipe from the underground compressed air source of the coal mine, and manually or mechanically drag the reset traction rope to compress the impact spring, thereby placing the spring limit block within the trigger limit port, thus constraining the movement of the impact cone and impact cylinder in the axial direction of the gas drainage borehole; then, pull the drag rope set on the limit pawl to move the impact repair device, PE pipe and limit pipe toward the gas drainage borehole opening; then remove the quick connector on the PE pipe, add a new PE pipe, and reconnect the quick connector, and then repeat S2 to S3 until there is no obstruction in the gas drainage borehole when the impact repair device connected to the PE pipe is input, which indicates that the coal body at the collapse site has been completely impacted and scattered;

[0040] S5: Then pull the tow rope to remove the impact repair device, PE pipe, and limit pipe, and connect the extraction pipe to the underground gas extraction pipeline in the coal mine. Then the gas extraction operation can continue.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy, characterized in that: Repair is performed using an impact repair device, which includes an impact cone, an impact outer tube, an impact cylinder, an impact spring, an impact spring sheet, a trigger chamber, and a booster. The impact cylinder is located inside one end of the impact outer tube and connected to the impact cone. The impact spring connects the impact outer tube and the impact cylinder. An impact spring sheet, which applies force to the inner wall of the impact outer tube, is located on one side of the impact cylinder via a fixing pin. A spring sheet limiting block is located at the end of the impact spring sheet, and a trigger limiting port that mates with the spring sheet limiting block is located on the wall of the impact outer tube. A trigger chamber is located outside the limiting port, containing a trigger pin and a return spring for ejecting the spring clip limiting block. A booster is located on the outer wall of the impact outer tube for activating the trigger pin. The booster includes a support base and a booster housing. Inside the booster housing are a booster input end, a booster roller, a booster output end, and an impact inclined block. The booster input end is connected to a compressed air source in the coal mine via a flexible hose. The booster input end, booster roller, booster output end, and impact inclined block are connected sequentially. Compressed air ejects the impact inclined block, thereby pressing down... A trigger pin pushes out the spring-loaded limiting block, causing the impact cylinder to spring out under the action of the impact spring, using the impact cone to impact the collapsed coal body; the tail end of the impact cylinder is equipped with a reset traction rope for pulling the impact cylinder back, causing the spring-loaded limiting block to engage with the trigger limiting port, thereby resetting the impact cylinder; a limiting pawl is hinged to the wall of the limiting tube; it also includes a support spring, one end of which is connected to the limiting tube and the other end to the limiting pawl, which is connected to a drag rope; the outer impact tube is equipped with an impact limiting port for... This design restricts the displacement of the impact cone and impact cylinder when they impact the collapsed coal, preventing the impact cylinder from ejecting. The booster input end is connected to the underground compressed air source in the coal mine, transmitting the pressure from the underground compressed air source to the tail of the booster input end, which is equipped with an inclined surface. The end of the booster output end is also an inclined surface, and the pressure from the underground compressed air source acting on the booster input end is transmitted through the inclined surface of the booster input end, the booster roller, and the inclined surface at the end of the booster output end to the impact block at the tail of the booster output end. The method includes the following steps: S1: Connect the impact repair device to the PE pipe through the first flange, and send the impact repair device to the location where the gas drainage borehole has collapsed; connect the PE pipe to the limiting pipe through the second flange. During the process of sending the impact repair device in, the limiting pawl set on the wall of the limiting pipe can contact the inner wall of the drainage pipe under the action of the supporting spring, and can restrict the impact repair device and the PE pipe from moving towards the gas drainage borehole opening; then connect the limiting pipe to the gas transmission pipe through the third flange; connect the gas transmission pipe to the compressed air source in the coal mine. S2: Open the compressed air source in the coal mine to allow high-pressure gas to enter the gas delivery pipe. Through the hose, the booster input end moves towards the bottom of the gas drainage borehole, and then its inclined surface contacts the booster roller, causing the booster output end to also move towards the bottom of the gas drainage borehole. Finally, the impact block hits the inclined surface at the top of the trigger pin, and the trigger pin moves towards the axis of the impact outer tube. Finally, the spring limit block moves downward, so that the impact cone and impact cylinder impact the coal body at the collapse site under the action of the impact spring, causing the coal body at the collapse site to scatter. S3: Disconnect the gas delivery pipe from the underground compressed air source in the coal mine, drag the reset traction rope to compress the impact spring, causing the spring plate limit block to be in the trigger limit port, thus constraining the movement of the impact cone and impact cylinder in the axial direction of the gas drainage borehole; pull the drag rope set on the limit pawl to move the impact repair device, PE pipe and limit pipe toward the gas drainage borehole opening; then remove the quick connector on the PE pipe, add a new PE pipe and reconnect the quick connector, repeat S1~S2 until there is no obstruction in the gas drainage borehole when the impact repair device connected to the PE pipe is input, indicating that the coal body at the collapse site has been completely impacted and scattered. S4: Then pull the tow rope to remove the impact repair device, PE pipe, and limit pipe, connect the extraction pipe to the underground gas extraction pipeline of the coal mine, and continue the gas extraction operation.

2. The method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy according to claim 1, characterized in that: Before step S1, a gas drainage borehole is first constructed in the coal seam using appropriate drilling equipment. After sealing the borehole, a drainage pipe is inserted and connected to the underground gas drainage pipeline of the coal mine, so that the gas drainage borehole and the underground gas drainage pipeline network are connected and connected. Then, the gas concentration and gas volume extracted from the gas drainage borehole are observed daily. If the gas concentration and gas volume extracted from the borehole are found to be close to 0, and the gas concentration and gas volume extracted from adjacent boreholes are within the normal range, it is determined that the borehole has collapsed. At this time, the connection between the drainage pipe and the underground gas drainage pipeline of the coal mine is removed, and step S1 is executed.

3. The method for repairing gas drainage boreholes in soft coal seams based on pressurized transmission of impact energy according to claim 1, characterized in that: The booster input end of the booster is provided with an inclined surface at an angle of A, and the end of the booster output end is provided with an inclined surface at an angle of B. The pressure from the underground compressed air source in the coal mine acting on the booster input end can be transmitted to the impact block at the tail of the booster output end through the inclined surface of the booster input end, the roller, and the inclined surface at the end of the booster output end. The force transmission relationship is as follows: Where A is the slope angle at the tail of the boost input terminal, and B is the slope angle at the end of the boost output terminal, where A <B。

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