Protective structure for gas extraction borehole and method thereof

Abstract

The present application relates to the technical field of coal mine safety protection, and discloses a protection structure and method of gas extraction drilling, which comprises a box, a four-way pipe and an air bag. Two through holes are formed in the upper part of the box, one of which is connected with a second pipeline. The other end of the second pipeline is used for being connected with a negative pressure pipeline, so that gas is sucked into the negative pressure pipeline. The four-way pipe is connected above the box. The lower end of the four-way pipe is connected with the other through hole of the box through a first pipeline. One of the transverse ports of the four-way pipe is sealingly connected with a hole sealing pipe at the outlet of the drilling. The other transverse port is connected with a sealing sleeve for sealing the gap between the drilling tool. The air bag is connected with the four-way pipe. One side opening of the air bag is connected with the top longitudinal port of the four-way pipe through a third pipeline. The other side opening of the air bag is connected with a fourth pipeline for being connected with the negative pressure pipeline. With the ejection of gas, coal residue and coal residue water, the three are respectively introduced into the box and the air bag through the four-way pipe.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mine safety protection, and particularly relates to a protection structure of a gas extraction drilling hole and a method thereof. BACKGROUND

[0002] Due to the gas contained in the coal seam, with the production activities such as coal mining and tunneling, the coal body is broken, and the gas is accelerated to flow out, which may cause serious accidents such as gas explosion and personnel suffocation. The most effective gas control measure at present is to construct a gas extraction drilling hole in the coal seam before the production activities start, so as to extract the gas in the coal seam and release the gas pressure in the coal body in advance. The gas content is greatly reduced, and the coal body after gas extraction will not cause a large amount of gas to be released, which affects the safety. The current method is to first use a reamer to ream a hole in the coal wall (the depth of the reaming section is generally 6m to 15m), then a hole sealing pipe is inserted into the reaming section, a hole sealing material is filled between the hole sealing pipe and the hole wall, and then a drill smaller than the hole sealing pipe is used to pass through the hole sealing pipe to continue to construct the gas extraction drilling hole.

[0003] In the existing extraction and tunneling device, the gas extraction is usually provided with an extraction device at the hole sealing pipe. The device usually includes a negative pressure pipeline and a rotor induced fan in communication with the negative pressure pipeline. The high-speed rotation of the rotor induced fan generates negative pressure in the negative pressure pipeline, so that the gas leaked from the outer wall of the reaming hole in the coal body is quickly sucked. When the drill continues to tunnel, the drill inserted into the drilling hole is provided with a water outlet hole to cool the drill. The cooling water leaks from the drill to the bottom of the hole outside the pool. Because the pressure of the gas in the coal body at different depths is different, the speed of the coal slag and coal slag water flowing into the pool is also different. In order to prevent the coal slag and coal slag water from splashing on the drilling equipment, the current extraction and tunneling device usually provides a blocking plate at the position of the pool close to the hole sealing pipe, which can block the splashing and impact of the coal slag and coal slag water.

[0004] However, when the drilling depth of the existing extraction and tunneling device approaches 100 meters, the innermost space of the drilling hole is narrow, which often causes poor drainage of the slag and water, and easily causes the accumulation of coal slag and water, so that the gas pressure can continue to accumulate. When the gas pressure exceeds the limit, a large amount of coal slag and coal slag water is easily ejected from the drilling hole, so that the blocking plate is difficult to completely block the coal slag and coal slag water ejected from the hole. The coal slag and water carrying the coal slag will cause the personnel to be injured, the drilling machine to be covered with coal mud, and even the destruction of the working environment. Moreover, the rapidly ejected leaked gas will mix with water and slag, and the negative pressure pipeline is difficult to quickly suck the gas from the mixed gas, water and slag, thereby causing the leakage of gas in the mine, which seriously threatens the safety of personnel. SUMMARY

[0005] The application provides a gas extraction drilling protection structure and method, which can avoid the coal residue and water carrying the coal residue from rebounding and splashing to injure people and avoid the massive leakage of gas.

[0006] The application provides a gas extraction drilling protection structure, which comprises a box body, a four-way pipe and an air bag.

[0007] Preferably, the two openings of the air bag are opposite, and a transverse screen pipe is connected between the two opposite openings of the air bag.

[0008] Preferably, a blocking net is arranged at the position of the screen pipe close to the fourth pipe to prevent the coal residue from entering the fourth pipe.

[0009] Preferably, a through hole is further arranged in the lower side wall of the box body, and an opening is further arranged in the lower part of the air bag.

[0010] Preferably, pneumatic valves are connected between the box body and the second pipe and between the air bag and the fourth pipe to realize remote control of the opening and closing of the second pipe and the fourth pipe.

[0011] Preferably, considering the suddenness of the occurrence of the drilling jet, there has been a lack of monitoring means in the past, and only the drilling depth when the jet occurs can be recorded, and it is difficult to analyze the jet occurrence law, therefore, the box is connected with a control terminal, the control terminal includes a data processing unit and a control unit, two pneumatic valves and two control valves are electrically connected with the control unit, the data processing unit of the control terminal is used for input analysis of the drill bit, gas pressure, gas concentration, drill rod displacement and other parameters, to automatically control the remote automatic opening and closing of each pneumatic valve and each control valve through the control unit.

[0012] Preferably, the control terminal further includes a transceiver unit for data reception and transmission, the top of the four-way pipe is provided with three through holes, and a gas concentration sensor for detecting gas concentration, a pressure sensor for detecting gas pressure and a visual recognition camera for monitoring the horizontal displacement state of the drill rod are respectively inserted and sealingly connected in the three through holes, and the gas concentration sensor, the pressure sensor and the visual recognition camera are electrically connected with the transceiver unit of the control terminal.

[0013] Preferably, the air bag is made of rubber or waterproof canvas material and can deform when inflated.

[0014] Preferably, the third pipeline and the fourth pipeline are both sleeved with a fixing sleeve, the fixing sleeve is fixedly connected with the top coal body through a lifting chain, and the top of the air bag is fixedly connected with a plurality of ear hooks.

[0015] The application also includes a protection method of the protection structure of the gas extraction drilling, comprising the following steps:

[0016] S1, control the drill bit of the drill to pass through one side of the sealing sleeve into the four-way pipe until the drill bit passes through the four-way pipe into the hole sealing pipe, and control the rotation and feeding of the drill rod;

[0017] S2, as the gas, coal ash and coal ash water are sprayed out at high speed, the gas concentration sensor and the pressure sensor sense in advance and send data to the transceiver unit of the control terminal, the data processing unit converts the signal received by the transceiver unit into a control signal and transmits it to the control unit, the control unit remotely fully opens the pneumatic valve, and controls the control valve to be in a closed state;

[0018] S3, as the gas, coal ash and coal ash water enter into the four-way pipe, a large amount of gas gas preferentially flows into the air bag to make the air bag rapidly expand, and is sucked into the second pipeline and the fourth pipeline under the action of negative pressure suction force until being sucked away by the negative pressure pipeline, the coal ash and the coal ash water preferentially enter into the box relying on gravity and settle.

[0019] Compared with the prior art, the beneficial effects of the present application are that: the present application can realize closed treatment of gas, coal cinder and coal cinder water when the gas, coal cinder and coal cinder water occur to be jetted out, so as to avoid the leakage of gas, water carrying coal cinder and coal cinder, the injury of personnel, the covering of drilling machine by coal sludge and the damage of working environment, and solve the problem that the gas is difficult to be sucked by the negative pressure pipeline when the gas is under high pressure and contains a large amount, and finally causes a large amount of gas leakage. The present application also utilizes the characteristics that the gas is light and the coal cinder and coal cinder water are heavy, so as to realize the effect of classified treatment of gas, coal cinder and coal cinder water. Specifically, the gas is filled by using the air bag as the core, and the deformation and expansion of the air bag are utilized to cope with the high pressure and large amount of gas, so as to play a buffering effect for the gas suction, and the negative pressure pipeline can realize the separate and rapid suction of most of the gas mixed in the jet hole, so as to avoid the leakage of gas in the mine and ensure the safety of personnel. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 A structure diagram of a protection structure of a gas extraction drilling hole provided by the embodiment of the present application is shown in the figure.

[0021] Figure 2 A structure diagram of a protection structure of a gas extraction drilling hole provided by the embodiment of the present application is shown in the figure. Figure 1 A partial enlarged view of part A in the figure.

[0022] Figure 3 A structure diagram of a protection structure of a gas extraction drilling hole provided by the embodiment of the present application is shown in the figure.

[0023] Figure 4 A structure diagram of a protection structure of a gas extraction drilling hole provided by the embodiment of the present application is shown in the figure.

[0024] Figure 5 A principle diagram of a BP network prediction of a jet hole occurrence probability of a protection structure of a gas extraction drilling hole provided by the embodiment of the present application is shown in the figure.

[0025] Figure 6 A method flow chart of a protection structure of a gas extraction drilling hole provided by the embodiment of the present application is shown in the figure.

[0026] BRIEF DESCRIPTION OF DRAWINGS

[0027] 1, four-way pipe; 2, sealing sleeve; 3, box; 4, first pipeline; 5, second pipeline; 6, air bag; 7, third pipeline; 8, fourth pipeline; 9, control valve; 10, screen pipe; 11, screen hole; 12, barrier net; 13, fifth pipeline; 14, pneumatic valve; 15, control terminal; 16, gas concentration sensor; 17, pressure sensor; 18, visual identification camera; 19, fixing sleeve; 20, hoisting chain; 21, hanging ear; 22, hoisting chain. DETAILED DESCRIPTION

[0028] One specific embodiment of the present application will be described in detail below with reference to the accompanying drawings, but it should be understood that the scope of protection of the present application is not limited by the specific embodiment.

[0029] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the technical solutions of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0030] Reference Figure 1 , Figure 2 and Figure 3 , the present application provides a kind of protection structure of gas extraction drilling, comprising: box 3, four-way pipe 1, air bag 6, box 3 upper portion is provided with two through holes, one of which is communicated with second pipeline 5, the other end of second pipeline 5 is used to be communicated with the negative pressure pipeline of suction gas gas, so that gas is sucked into negative pressure pipeline, four-way pipe 1 is connected to the upper portion of box 3, the lower end of four-way pipe 1 is communicated with the other through hole of box 3 by first pipeline 4, one of the transverse ports of four-way pipe 1 is sealingly connected with the sealing pipe at the outlet of drilling, the other transverse port is connected with sealing sleeve 2 for blocking the gap between drilling tool, air bag 6 is connected to the upper portion of four-way pipe, air bag 6 is provided with two openings, one side opening is communicated with the top longitudinal port of four-way pipe 1 by third pipeline 7, the other side opening of air bag 6 is communicated with fourth pipeline 8 for being communicated with negative pressure pipeline, with the ejection of gas, coal dregs and coal dregs water, all of them are respectively entered into box 3 and air bag 6 through four-way pipe 1, the amount of gas in air bag 6 is greater than that in box 3, the amount of coal dregs and coal dregs water in box 3 is greater than that in air bag 6.

[0031] In the above embodiment, the four-way pipe 1, the box body 3, the air bag 6, the first pipeline 4 and the third pipeline 7 are arranged, so that the closed treatment of the gas, the coal cinder and the coal cinder water can be realized when the gas, the coal cinder and the coal cinder water are sprayed, the leakage of the gas in the mine is avoided as much as possible, the situation that the personnel are injured, the drilling machine is covered by the coal sludge and the working environment is damaged due to the rebound and the splashing of the water and the coal cinder carrying the coal cinder is avoided, the problem that the gas is difficult to be sucked by the negative pressure pipeline due to the high pressure and the large amount of the gas is solved, the gas, the coal cinder and the coal cinder water can be classified and treated according to the characteristics that the gas is light in weight and the coal cinder and the coal cinder water are heavy in weight, the air bag 6 is used as the core to fill the gas, the deformation and expansion of the air bag 6 are used to deal with the high pressure and the large amount of the gas, so that the buffering effect of the gas suction is realized, the negative pressure pipeline can quickly suck most of the gas from the mixed gas, water and cinder after the spraying, the leakage of the gas in the mine is avoided, and the safety of the personnel is ensured, the sealing sleeve 2 is made of high molecular polyethylene material, and the sealing ring is arranged in the sealing sleeve 2.

[0032] Further, referring to Figure 4 , the two openings of the air bag 6 are opposite to each other, the transverse sieve pipe 10 is connected between the two opposite openings of the air bag 6, the two ends of the sieve pipe 10 are respectively communicated with the two openings of the air bag 6, and the two ends of the sieve pipe 10 are respectively inserted and fixed in the third pipeline 7 and the fourth pipeline 8, and a plurality of sieve holes 11 are formed in the sieve pipe 10 in the circumferential direction.

[0033] In the above embodiment, the sieve pipe 10 is arranged, so that the two openings of the air bag 6 can be assisted and supported, the high-speed splashing coal cinder and coal cinder water can be prevented from entering the air bag 6, and the inner wall of the air bag 6 is prevented from being damaged, and the sieve holes 11 are used to make the coal cinder and the coal cinder water fall to the bottom of the air bag 6.

[0034] Further, referring to Figure 4 , a through hole is further formed in the lower side wall of the box body 3, an opening is further formed in the lower portion of the air bag 6, the opening in the bottom of the air bag 6 and the through hole in the bottom of the box body 3 are connected with control valves 9, the other ends of the two control valves 9 are respectively communicated with fifth pipelines 13, the two fifth pipelines 13 are used to be communicated with the slag discharge pipeline, the other ends of the two control valves 9 are respectively communicated with fifth pipelines, the two fifth pipelines are used to be communicated with the slag discharge pipeline, and the sieve pipe 10 is provided with a blocking net 12 for blocking the coal cinder at the position close to the fourth pipeline 8.

[0035] In the above embodiment, the fifth pipeline 13 is arranged, so that the coal cinder water and the coal cinder can be uniformly discharged, and the blocking net 12 is arranged, so that the coal cinder and the coal cinder water can be prevented from flowing into the fourth pipeline 8.

[0036] Further, referring to Figure 1 The other end of the two control valves 9 is communicated with the fifth pipeline 13, and the two fifth pipelines 13 are communicated with the residue discharge pipeline.

[0037] Further, referring to Figure 1 The pneumatic valve 14 is connected between the box body 3 and the second pipeline 5 and between the air bag 6 and the fourth pipeline 8.

[0038] In the above embodiment, the pneumatic valve 14 is arranged to realize remote control of the opening and closing of the second pipeline 5 and the fourth pipeline 8. Specifically, the electromagnetic valve is used to control the opening and closing of the air path, and the opening of the pneumatic valve 14 is controlled.

[0039] Further, referring to Figure 1 and Figure 2 Considering the suddenness of the occurrence of the drilling orifice, there has been a lack of monitoring means in the past, and only the drilling depth when the orifice occurs can be recorded, and it is difficult to analyze the orifice occurrence law. Therefore, the control terminal 15 is connected to the box body 3, the control terminal 15 includes a data processing unit and a control unit, the two pneumatic valves 14 and the two control valves 9 are electrically connected to the control unit, and the data processing unit of the control terminal 15 is used to analyze the input parameters of the drill bit, gas pressure, gas concentration, drill rod displacement and the like. The control unit is used to automatically control the remote automatic opening and closing of each pneumatic valve 14 and each control valve 9.

[0040] The control terminal 15 further includes a transceiver unit for data receiving and sending, three through holes are formed in the top of the four-way pipe 1, and a gas concentration sensor 16 for detecting gas concentration, a pressure sensor 17 for detecting gas pressure and a visual recognition camera 18 for monitoring the horizontal displacement state of the drill rod are respectively inserted and sealingly connected in the three through holes. The gas concentration sensor 16, the pressure sensor 17 and the visual recognition camera 18 are electrically connected to the transceiver unit of the control terminal 15.

[0041] In the above embodiments, the present application inputs the data information of the drilling aperture, drill bit diameter, drill rod diameter, and drilling inclination angle into the data processing unit of the control terminal 15 before drilling construction, and records the drilling depth, orifice gas pressure, and gas concentration during the drilling construction process. Specifically, the reason for recording the pressure and concentration simultaneously is that the orifice four-way pipe 1 belongs to a semi-closed space, and the sealing degree thereof is closely related to the gap between the four-way cross pipe outer sealing sleeve 2 and the drill rod. However, the sealing sleeve 2 is essentially made of hard plastic or rubber material, and the degree of wear and the timeliness of replacement thereof are often unstable due to the judgment of the site operation personnel. The use of the concentration and pressure dual indicators can effectively offset the impact caused by different sealing degrees. If the sealing sleeve 2 is worn seriously, the four-way pipe 1 has poor sealing performance, and then the jet hole occurs, because it is connected with the outside world, the pressure is not easy to accumulate rapidly, and the pressure data is relatively lagging in judging the jet hole. However, because it is connected with the outside world, the gas concentration in the four-way pipe 1 is low, and once the jet hole occurs, the concentration will immediately rise significantly, which can effectively determine the jet hole. If the sealing sleeve 2 is replaced in time, the gap between the sealing sleeve 2 and the drill rod is small, and the sealing degree of the four-way pipe 1 is high, so that the four-way pipe 1 has a high gas concentration under normal circumstances. After the jet hole occurs, the concentration in the four-way pipe 1 does not rise significantly, and the concentration is lagging as a judgment index. However, because the sealing degree is high, the pressure is easy to accumulate, and the pressure can be used as an effective and sensitive index for judging the jet hole. Through the control terminal 15, a big data analysis model for the jet hole in the drilling construction can be established, and the mechanism and law of the jet hole can be more accurately determined.

[0042] At the same time, the data processing unit prediction model combines the real-time recorded data of the gas concentration, gas pressure, and drilling depth by the gas concentration sensor 16, the pressure sensor 17, and the visual recognition camera 18. Once the jet hole occurs, if the change amplitude of the gas pressure and concentration or the absolute value of the concentration reaches the set value within a short time, the set value is initially set according to the gas pressure and gas content of the drilled coal seam, and the subsequent recommended value is determined according to the big data analysis model, then it is immediately determined that the jet hole occurs. Through the control unit, the closing of the control valve 9 is realized, so that the opening of the pneumatic valve 14 is realized. In this way, the jet hole can be quickly responded to, the gas can be pumped out, the safety can be ensured, and the control valve 9 can be closed in time after the jet hole is over, so as to avoid the negative pressure suction effect of the extraction system. After the jet hole is over, the control valve 9 is opened, so that the coal slag and coal slag water can be effectively discharged. This design effectively avoids the situation that the coal slag water and coal slag fill the box 3 or the air bag 6, causing the subsequent water and coal slag to enter the second pipeline 5 or the fourth pipeline 8, reduces the risk of blockage and interruption, and improves the extraction efficiency.

[0043] The use of the visual recognition camera 18 not only improves the accuracy of the drilling depth calculation, but also provides more data support for the establishment of the jet hole model. Meanwhile, the application of the fusion algorithm makes the drilling construction process more transparent, which is convenient for examination and management, and improves the standardization and efficiency of the operation.

[0044] Specifically, the present application establishes a jet hole degree evaluation model according to the drilling hole diameter, drill bit diameter, drill rod diameter, drilling angle, drilling depth, orifice gas pressure, and orifice gas concentration by using a BP neural network. When the jet hole degree evaluation is higher than the set threshold, it is determined that jet hole occurs. In this way, the jet hole can be quickly responded to, the gas can be pumped out, the safety can be ensured, and the valves can be opened and closed in time after the jet hole is over.

[0045] Specifically, as shown in Figure 5 , the input layer data is , which respectively represents the drilling hole diameter, drill bit diameter, drill rod diameter, drilling angle, drilling depth, orifice gas pressure, and orifice gas concentration.

[0046] The middle calculation process has two hidden layers, which are respectively named . The data is linearly transformed by weight value and bias term, and then passes through the activation layer to obtain the output of the hidden layer, that is, the input of the next layer.

[0047] The parameters of the input layer to the hidden layer are , wherein is the weight value, is the bias term; the parameters of the hidden layer to the hidden layer are , wherein is the weight value, is the bias term; the parameters of the hidden layer to the output layer are , wherein is the weight value, is the bias term. The activation function is , , . Therefore, the model layers are set as follows:

[0048]

[0049]

[0050]

[0051] All data input forms in the calculation process are vectors.

[0052] In the above formula, is the transpose of the vector, is the output of the hidden layer ( ), is the output of the hidden layer ( ), is the model output, i.e., the probability of the model predicting the occurrence of the orifice:

[0053]

[0054] where the activation function , is the ReLU (Rectified Linear Unit) function:

[0055]

[0056]

[0057]

[0058] In the formula, the weight value is the coefficient of the connection between neurons (neurons are represented by circular symbols).

[0059] In this model, the weight determines the degree of influence of the input parameters on the output result (i.e., the predicted probability). The weight is constantly adjusted during the training process to make the model's prediction results as accurate as possible.

[0060] The bias term is an additional parameter for the neuron output, which provides a fixed offset when there is no input.

[0061] The bias term can make the model's activation function better fit the training data, thereby improving the model's prediction ability.

[0062] The activation function , , in the model is a crucial component that introduces nonlinearity, enabling the model to better learn and represent complex data relationships.

[0063] Further, referring to Figure 1 , the air bag 6 is made of rubber or waterproof canvas material.

[0064] In the above embodiments, by limiting the air bag 6 to be made of rubber or waterproof canvas material, it can deform when inflated to cope with high-pressure and large-volume gas, thereby playing a buffering effect for gas suction.

[0065] Further, referring to Figure 1The third pipeline 7 and the fourth pipeline 8 are sleeved with fixing sleeves 19, the fixing sleeves 19 are fixed to the top coal body through hoisting chains 20, the top of the air bag 6 is fixed with a plurality of hanging ears 21, and the hanging ears 21 are fixed to the top coal body through hoisting chains 22.

[0066] In the above embodiment, the fixing sleeves 19 are fixed to the third pipeline 7 and the fourth pipeline 8.

[0067] Further, referring to Figure 6 The application also includes a protection method of the protection structure of the gas extraction drilling hole, which comprises the following steps:

[0068] S1, the drill bit of the drilling tool is controlled to pass into the four-way pipe 1 from one side of the sealing sleeve 2 in a transverse direction until the drill bit passes through the four-way pipe 1 and enters the hole sealing pipe, and the rotation and feeding of the drill rod are controlled;

[0069] S2, as the gas, coal slag and coal slag water are sprayed outwards at a high speed, the gas concentration sensor 16 and the pressure sensor 17 sense in advance and send data to the transceiving unit of the control terminal 15, the data processing unit converts the signal received by the transceiving unit into a control signal and transmits the control signal to the control unit, the control unit remotely opens the pneumatic valve 14 completely, and the control valve 9 is in a closed state;

[0070] S3, as the gas, coal slag and coal slag water enter the four-way pipe 1, a large amount of gas preferentially flows into the air bag 6 to make the air bag 6 expand rapidly, and the gas is sucked into the second pipeline 5 and the fourth pipeline 8 under the action of the negative pressure suction force until the gas is sucked away by the negative pressure pipeline, the coal slag and the coal slag water preferentially enter the box body 3 under the action of gravity and are settled.

[0071] Specifically, in the normal state without the occurrence of the blowout phenomenon, the pneumatic valve 14 connected with the gas bag 6 is closed, the two control valves 9 are opened, the cinder and the cinder water are affected by gravity and enter the box body 3, the gas is discharged from the pneumatic valve 14 of the box body 3, and the water cinder is discharged from the control valve 9, while a large amount of gas is accompanied by the water cinder to enter the four-way pipe 1, and the gas is sprayed outwards at a high speed along with the gas, the cinder and the cinder water, the gas concentration sensor 16 and the pressure sensor 17 are sensed in advance, and data is sent to the transceiving unit of the control terminal 15, the data processing unit converts the signal received by the transceiving unit into a control signal and transmits it to the control unit, the control unit remotely and completely opens the pneumatic valve 14, and controls the control valve 9 to be in a closed state, at this time, the gas with a large amount of pressure enters the gas bag 6 through the third pipeline 7 and enters the screen pipe 10 to release the pressure on the gas bag 6, the gas bag 6 can play a good buffering effect due to its material characteristics, the water cinder is discharged by the control valve 9 after sinking to the gas bag 6, and the high-pressure gas is discharged to the fourth pipeline 8 through the pneumatic valve 14, then the pneumatic valve 14 connected with the box body 3 is opened and the pneumatic valve 14 connected with the gas bag 6 is closed when the blowout pressure and concentration detected by the gas concentration sensor 16 and the pressure sensor 17 tend to be stable, so as to avoid the emptying phenomenon of the drainage pipeline, since the visual recognition camera 18 is arranged in the four-way pipe 1, the device can realize real-time visual recognition of the rod insertion and rod withdrawal of the drill rod in a dark environment, accurately record the rod insertion and rod withdrawal times, and can assist in judging the blowout through deep learning and image characteristics of the blowout.

[0072] In summary, the present application can ensure the blowout prevention and avoid gas leakage, and through the technical features of accurate prediction, rapid response, effective separation and discharge, intelligent monitoring and deep calculation, the safety and efficiency of the coal mine gas extraction drilling operation are significantly improved, and a powerful guarantee is provided for the safety production of coal mines.

[0073] The above disclosure is only some specific embodiments of the present application, but the embodiments of the present application are not limited thereto, and any changes that can be thought of by those skilled in the art shall fall within the protection scope of the present application.

Claims

1. A protective structure for a gas extraction borehole, characterized in that, include: The box body (3) has two through holes on the upper part, one of which is connected to a second pipe (5), and the other end of the second pipe (5) is used to connect to a negative pressure pipe for absorbing gas. Four-way pipe (1) is connected to the top of the box (3). The lower end of the four-way pipe (1) is connected to another through hole of the box (3) through the first pipe (4). One of the horizontal ports of the four-way pipe (1) is sealed to the sealing pipe at the borehole outlet, and the other horizontal port is connected to a sealing sleeve (2) for sealing the gap between the pipe and the drill bit. An airbag (6) is connected to the top of a four-way pipe. The airbag (6) has two openings. One opening is connected to the top longitudinal port of the four-way pipe (1) via a third pipe (7). The other opening of the airbag (6) is connected to a fourth pipe (8) for connecting to the negative pressure pipe. As gas, coal ash, and coal ash water are ejected, they all enter the box (3) and the airbag (6) respectively through the four-way pipe (1). The amount of gas in the airbag (6) is greater than the amount of gas in the box (3). The amount of coal ash and coal ash water in the box (3) is greater than the amount of coal ash and coal ash water in the airbag (6). The two openings of the airbag (6) are connected to the top longitudinal port of the four-way pipe (1) via a third pipe (7). The two openings on the sides of the airbag (6) are connected by a transverse sieve tube (10). The two ends of the sieve tube (10) are respectively connected to the two openings of the airbag (6). The two ends of the sieve tube (10) are respectively inserted and fixed in the third pipeline (7) and the fourth pipeline (8). The sieve tube (10) has multiple sieve holes (11) along its circumference. The lower side wall of the box (3) also has a through hole. The lower part of the airbag (6) also has an opening. The opening at the bottom of the airbag (6) and the through hole at the bottom of the box (3) are both connected to control valves (9). The other side of the two control valves (9) Each end is connected to a fifth pipeline (13), and the two fifth pipelines (13) are used to connect to the slag discharge pipeline. Pneumatic valves (14) are connected between the box (3) and the second pipeline (5), and between the airbag (6) and the fourth pipeline (8). A control terminal (15) is connected to the box (3). The control terminal (15) includes a data processing unit and a control unit. The two pneumatic valves (14) and the two control valves (9) are electrically connected to the control unit. The data processing unit of the control terminal (15) is used to analyze the input parameters of the drill bit, gas pressure, gas concentration, and drill rod displacement, and the data is processed by the control unit. The remote automatic opening and closing of each pneumatic valve (14) and each control valve (9) is controlled respectively. The control terminal (15) also includes a transceiver unit for data reception and transmission. The top of the four-way pipe (1) has three through holes. The three through holes are respectively inserted and sealed to a gas concentration sensor (16) for detecting gas concentration, a pressure sensor (17) for detecting gas pressure, and a visual recognition camera (18) for monitoring the horizontal displacement of the drill rod. The gas concentration sensor (16), pressure sensor (17) and visual recognition camera (18) are all electrically connected to the transceiver unit of the control terminal (15).

2. The protective structure for a gas extraction borehole as described in claim 1, characterized in that, The screen tube (10) is provided with a barrier net (12) for blocking coal slag near the fourth pipeline (8).

3. The protective structure for a gas extraction borehole as described in claim 1, characterized in that, The airbag (6) is made of rubber or waterproof canvas.

4. The protective structure for a gas extraction borehole as described in claim 1, characterized in that, The third pipeline (7) and the fourth pipeline (8) are both fitted with a fixing sleeve (19). The top of the fixing sleeve (19) is fixed to the top coal body by a hoisting chain (20). The top of the airbag (6) is fixed with multiple hanging ears (21), and the hanging ears (21) are fixed to the top coal body by a hoisting chain (22).

5. A protection method for the protective structure of a gas drainage borehole as described in claim 1, characterized in that, Includes the following steps: S1. As the gas, coal slag and coal slag water are ejected outward at high speed, the gas concentration sensor (16) and pressure sensor (17) sense in advance and send the data to the transceiver unit of the control terminal (15). The data processing unit converts the signal received by the transceiver unit into a control signal and transmits it to the control unit. The control unit remotely fully opens the pneumatic valve (14) and controls the control valve (9) to be in the closed state. S2. As the gas, coal slag and coal slag water enter the four-way pipe (1), a large amount of gas will preferentially flow into the air bag (6) to make the air bag (6) expand rapidly. Under the action of negative pressure suction, it will be drawn into the second pipe (5) and the fourth pipe (8) respectively until it is drawn away by the negative pressure pipe. The coal slag and coal slag water will preferentially enter the box (3) by gravity and settle down.

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