Blowout prevention structure for drilling gas hole in coal mine

Abstract

The utility model relates to the technical field of coal mine gas mining equipment, in particular to a blowout prevention structure for drilling a gas hole in a coal mine, which comprises an in-hole sealing element, a dust catching component, a pumping and discharging pipe, a dust falling component and a buffer cylinder provided with a sensor which are communicated in sequence, and is characterized in that a connecting pipe is arranged between the tail end of the in-hole sealing element and the dust catching component; a quick pipe for directly communicating the connecting pipe with the buffer cylinder is arranged on the connecting pipe, and a pressure valve capable of sealing the quick pipe is arranged on the quick pipe. The quick pipe bypasses the dust removal structure and is directly communicated with the buffer cylinder, and the technical problems that in the prior art, a blowout prevention structure for coal mine gas hole drilling lags behind and cannot respond in time are solved.

Description

Technical Field

[0001] The utility model relates to the field of coal mine gas mining equipment, in particular to a blowout prevention structure for drilling gas holes in coal mines. Background Art

[0002] Currently, during coal mining, coal rock releases gas. This gas is formed during the coal's formation and metamorphism. Because the gas generated during underground coal mining mixes with air and forms a flammable gas, it poses a significant safety hazard. Therefore, it is necessary to drill holes in the coal mine and seal them with extraction and drainage pipes to bring the gas deep within the mine to the surface, enabling gas extraction and treatment to ensure mining safety.

[0003] However, the gas in coal mines is unevenly distributed, so small-scale gas outbursts may occur during the drilling process. Gas outburst refers to the instantaneous outburst of a large amount of gas under the action of pressure. Therefore, when a gas outburst occurs, the pressure in the extraction pipe that guides the gas to the ground will suddenly increase. However, the cross-section of the pipe for extracting gas is constant, and the range of flow increase is limited. When the amount of gas gushing out during the gas outburst is greater than the flow rate of the gas extraction pipe, the gas pressure acts on the coal mine layer, destroying the structure of the coal mine layer. Although small-scale gas outbursts are not very destructive in a single instance, if no intervention is taken, multiple outbursts will form a cumulative effect, which will form a large number of small cracks in the structure of the coal rock mass, and then cause the coal rock mass to collapse, resulting in coal mine collapse accidents, which poses a great safety hazard to coal mine production.

[0004] To address this small-scale gas outburst problem, conventional techniques typically incorporate extraction equipment into the pneumatic slag removal system used to drill gas holes in coal mines. This extraction equipment is equipped with a negative pressure device, which activates when a gas outburst occurs, generating negative pressure. The pressure differential between the gas outburst and the negative pressure device is then used to rapidly extract the gas, quickly returning the pressure within the coal mine to normal. For example, patent application number CN202410136409.X discloses a blowout prevention and dust suppression device for gas hole drilling in coal mines. The device is equipped with a negative pressure motor for rapid extraction.

[0005] However, this method of using a negative pressure device to generate negative pressure for rapid extraction requires the detection of gas bulges first. However, the working environment of coal mining is a flammable and explosive working environment. It is required to minimize electrical equipment on site. In coal seam drilling, which is a working condition that comes into direct contact with gas, live equipment must be eliminated. Therefore, the electronic sensor for detecting gas bulges cannot be installed at the drill rod position of the borehole. It can only be installed at the buffer cylinder or wind tube position at the outer end of the extraction pipe of the wind slag discharge device. However, this installation method makes it impossible to detect gas bulges in time when they occur in the borehole. The bulging gas gas needs to pass through multiple dust removal devices such as the sealed dust collection components, slag discharge pipes, and dust reduction components in the hole and reach the buffer cylinder before it is detected. At this time, the equipment that creates negative pressure starts to create negative pressure, which has a lag and cannot respond in time. Utility Model Content

[0006] The purpose of the utility model is to provide a blowout prevention structure for drilling gas holes in coal mines, so as to solve the technical problem that the blowout prevention structure for drilling gas holes in coal mines in the prior art mentioned above has a lag and cannot respond in time.

[0007] In order to solve the above problems, the technical solution adopted by the utility model is as follows: a blowout prevention structure for gas drilling holes in coal mines, including an in-hole seal, a dust collecting component, an exhaust pipe, a dust reduction component and a buffer cylinder equipped with a sensor, which are connected in sequence. A connecting pipe is provided between the end of the in-hole seal and the dust collecting component. The connecting pipe is provided with a quick pipe that directly connects the connecting pipe and the buffer cylinder. The quick pipe is provided with a pressure valve that can close the quick pipe.

[0008] The beneficial effects of this embodiment are:

[0009] 1. Due to the flammable and explosive working environment of coal mining, electrical and electronic components cannot be installed. Therefore, the existing technology installs the gas detection sensor in the borehole at the buffer cylinder or wind tube position at the outer end of the extraction pipe. Because a large amount of coal powder is generated during the drilling process and needs to be discharged, during normal drilling, the coal powder needs to be separated from the gas and then the gas is extracted and discharged to the outside. Therefore, in-hole seals, dust collection components, extraction pipes, dust reduction components and other structures are set between the extraction pipe and the buffer cylinder to remove dust and separate coal powder. However, these structures cause the gas to slow down in the pipe, and it also takes a certain amount of time for the gas to reach the buffer cylinder. When a gas outburst occurs during the coal mine drilling process, it is impossible to respond in time. However, the present application uses a quick pipe to directly connect the connecting pipe and the buffer cylinder. When a gas outburst occurs, the gas can reach the buffer cylinder, making the response quick.

[0010] Furthermore, a blowout prevention hole is opened on the connecting pipe, the connecting pipe is connected to a blowout prevention pipe via the blowout prevention hole, and the connecting pipe is connected to the quick pipe via the blowout prevention pipe.

[0011] Furthermore, the blowout preventer is provided with a blowout preventer joint, the blowout preventer joint is provided with threads, and the blowout preventer is detachably connected to the quick hose via the threads.

[0012] Furthermore, the pressure valve is arranged in the blowout preventer to open and close the blowout preventer hole.

[0013] Furthermore, the pressure valve includes a fixed rod fixedly connected to the blowout preventer, a sliding groove is opened on the fixed rod, a sliding rod is slidably connected in the sliding groove, a spring is sleeved on the outer periphery of the sliding rod, and a sealing plate is fixedly connected to the end of the sliding rod away from the fixed rod, which can close the blowout preventer hole under the action of the spring.

[0014] Furthermore, the sealing plate is an arc-shaped plate with the same curvature as the outer periphery of the connecting rod, and the arc-shaped plate is covered with rubber. The arc-shaped structure fits the connecting rod better, and the elasticity of the rubber better covers the anti-spray hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the overall structure of the utility model.

[0016] Figure 2 This is a schematic diagram of the connection between the connecting pipe and the quick pipe of the utility model.

[0017] Figure 3 This is a schematic diagram of the connection position of the pressure valve and the connecting pipe of the utility model.

[0018] Figure 4 This is a schematic structural diagram of the pressure valve of the utility model. DETAILED DESCRIPTION

[0019] The following is further described in detail through specific implementation methods:

[0020] The reference numerals in the drawings of the specification include: in-hole seal 1, connecting pipe 11, blowout prevention hole 111, blowout prevention pipe 12, top plate 121, fixing rod 122, sliding rod 123, sealing plate 124, spring 125, blowout prevention joint 13, quick pipe 14, dust collecting component 2, exhaust pipe 3, dust reduction component 4, control box 5, buffer cylinder 6.

[0021] Implementation example Figure 1-4 As shown: a blowout prevention structure for gas drilling holes in coal mines, comprising an in-hole seal 1, a connecting pipe 11, a dust collecting component 2, a suction and exhaust pipe 3, a dust suppression component 4, and a buffer cylinder 6 which are connected in sequence.

[0022] like Figure 1As shown, the in-hole seal 1 is a metal tube with an annular airbag covering the outer circumference. By blowing air into the airbag, the airbag expands and seals the coal mine borehole. This prevents the particles and gas in the hole from escaping through the gap between the borehole and the seal, and can only flow outward from the metal tube of the in-hole seal, thus preventing excessive gas or coal dust from entering the coal mining tunnel. The rear end of the in-hole seal 1 is usually connected to the connecting pipe 11, and the rear end of the connecting pipe 11 is connected to the dust collecting component 2. The dust collecting component 2 is a three-way structure, and the end of its straight pipe portion is provided with a rotating sealing component. The rotating sealing component is used to perform a rotary seal on the straight pipe portion, so that the drill bit can pass through the dust collecting component 2 and the in-hole seal 1 to drill the coal mine, and the coal dust and gas generated by drilling cannot escape through the straight pipe portion. The inclined tube portion of the dust-collecting component 2 is directly connected to the extraction pipe 3, allowing coal dust to flow along the extraction pipe. The extraction pipe 3 is connected to the dust suppression component 4, which is equipped with a water mist nozzle. Therefore, the coal dust in the gas hole drilled in the coal mine is sprayed with water and gas by the water mist nozzle at the dust suppression component 4, which attaches to the dust suppression component 4, increasing its mass and separating it from the gas. It is then discharged into a conical slag discharge tube connected to the dust suppression component 4. The upper end of the conical slag discharge tube is connected to a buffer tube 6. The buffer tube 6 has a relatively large diameter and is connected to a negative pressure motor installed in the control box 5. The negative pressure motor generates a negative pressure, providing a pressure differential between the coal mine gas hole and the buffer tube. The buffer tube 6 is equipped with a carbon monoxide sensor and a laser methane sensor. These sensors detect the carbon monoxide and methane content in the exhaust gas and thus determine the gas content. During a gas outburst, they can detect a rapid increase in gas concentration and provide a signal to the negative pressure motor, causing it to create a higher negative pressure environment and rapidly extract the gas from the hole. However, when gas bursts, the coal powder and gas in the gas hole drilled in the coal mine need to flow through the seal 1 in the hole through the dust collecting component 2, the exhaust pipe 3, and the dust reduction component 4 before reaching the buffer cylinder 6. Therefore, when a small-scale gas burst occurs, the negative pressure motor cannot respond in time.

[0023] In this application, a blowout preventer 12 is provided at the upper end of the connecting pipe 11 between the end of the in-hole seal 1 and the dust collecting component 2. Figure 2 As shown, the lubricator 12 is a cylindrical structure with a sealed upper end. An integral blowout preventer joint 13 is provided at the right end of the lubricator 12. This joint 13 serves as the sole outlet for the lubricator 12. The right end of the joint 13 is threaded, allowing it to be removably and sealedly connected to a quick-release hose 14 using the threads and a gasket. The other end of the quick-release hose 14 is connected to the buffer cylinder 6, which also has a threaded joint for a sealed connection with the quick-release hose 14 (not shown).

[0024] like Figure 3 、 Figure 4As shown, the connecting pipe 11 and the lubricator 12 are directly connected through the lubricator hole 111, but a pressure valve is provided in the lubricator 12. The pressure valve includes a top plate 121, a fixed rod 122, a sliding rod 123, and a sealing plate 124. The top plate 121 of the pressure valve is welded to the inner wall of the upper end of the lubricator 12. The fixed rod 122 and the top plate 121 are an integral structure. A sliding groove with the same diameter as the sliding rod 123 is opened on the central axis of the fixed rod 122. The sliding rod 123 and the fixed rod 122 are slidably connected by the sliding groove. Therefore, part of the rod body of the sliding rod 123 can slide into the sliding groove and overlap with the fixed rod 122, thereby reducing the total length of the fixed rod 122 and the sliding rod 123. A sealing plate 124 is welded to the lower end of the sliding rod. The sealing plate 124 can completely seal the lubricating hole 111, so that the connecting pipe 11 and the lubricator 12 are no longer connected. A spring 125 is installed between the fixed rod 122 and the sliding rod 123. Under the action of the spring 125, the sliding rod 123 is pushed out of the sliding groove of the fixed rod 122, pressing the sealing plate 124 against the blowout prevention hole 111 to seal it. To ensure a good seal, the sealing plate 124 is a curved plate with a curvature that matches the outer circumference of the connecting tube 11, so that it fits tightly against the outer circumference of the connecting tube 11. The side of the sealing plate 124 closest to the connecting tube 11 is covered with rubber, which can be used to achieve a good sealing effect by utilizing the deformation force of the rubber.

[0025] During normal drilling, the elastic force of spring 123 pushes sliding rod 123 outward, driving sealing plate 124 to completely seal blowout prevention hole 111 on connecting rod 11. The coal dust and gas generated during drilling then flow normally through dust collection component 2, extraction pipe 3, and dust suppression component 4 to buffer cylinder 6, where they are separated and discharged. If a gas outburst occurs, the massive outflow of gas causes a sudden increase in pressure within the connecting pipe. This pressure exceeds the deformation force of spring 125, forcing part of sliding rod 123 to slide into the chute on fixed rod 122. This lifts sealing plate 124, allowing a large amount of gas to enter blowout prevention hole 12 and, via quick-release pipe 14, into buffer cylinder 6. This gas is detected by the carbon monoxide sensor and laser methane sensor, triggering the negative pressure motor to generate even greater negative pressure and rapidly extract the gas from the borehole. After gas extraction is complete, the pressure in the borehole returns to normal, and spring 125 returns to its original shape, resealing blowout prevention hole 111.

[0026] The above is only an embodiment of the present invention, and the commonly known specific structures and characteristics of the scheme are not described in detail here. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, and these should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection claimed by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A blowout prevention structure for gas drilling holes in coal mines, comprising a hole seal, a dust collecting component, a suction and exhaust pipe, a dust suppression component, and a buffer cylinder equipped with a sensor, which are connected in sequence, and is characterized by: A connecting pipe is provided between the end of the inner hole sealing member and the dust collecting component. The connecting pipe is provided with a quick pipe which directly connects the connecting pipe with the buffer cylinder. The quick pipe is provided with a pressure valve which can close the quick pipe.

2. The anti-blowout structure for gas drilling in coal mines according to claim 1, characterized in that: The connecting pipe is provided with a blowout prevention hole, the connecting pipe is connected to a blowout prevention pipe via the blowout prevention hole, and the connecting pipe is connected to a quick pipe via the blowout prevention pipe.

3. The anti-blowout structure for gas drilling in coal mines according to claim 2, characterized in that: The anti-blowout pipe is provided with an anti-blowout joint, and the anti-blowout joint is provided with threads. The anti-blowout pipe is detachably connected to the quick hose by using the threads.

4. The anti-blowout structure for gas drilling in coal mines according to claim 3, characterized in that: The pressure valve is arranged in the blowout preventer to open and close the blowout preventer hole.

5. The anti-blowout structure for gas drilling in coal mines according to claim 4, characterized in that: The pressure valve includes a fixed rod fixedly connected to the blowout preventer, a sliding groove is opened on the fixed rod, a sliding rod is slidably connected in the sliding groove, a spring is sleeved on the outer circumference of the sliding rod, and a sealing plate is fixedly connected to the end of the sliding rod away from the fixed rod, which can close the blowout preventer hole under the action of the spring.

6. The anti-blowout structure for gas drilling in coal mines according to claim 5, characterized in that: The sealing plate is an arc-shaped plate having the same arc as the outer periphery of the connecting rod, and the arc-shaped plate is covered with rubber.

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