A sealing buffer and over-limit protection system for underground drilling operations

Abstract

The invention discloses a sealing, buffering and over-limit prevention protection system for underground drilling construction operations, comprising an extrusion and expansion sealing device of a hole mouth, a coal and water automatic discharge sealing device, and a high-pressure gas decompression buffer device, wherein the extrusion and expansion sealing device is connected to the coal and water automatic discharge device, which is connected to the high-pressure gas shock-absorbing buffer device, and the extrusion and expansion sealing device comprises a casing and an anti-blowout cavity. The invention aims at the positions and characteristics of the blowout holes that are prone to hidden dangers of blowout holes during underground drilling construction in coal mines, and provides a drilling construction protection system that integrates the functions of sealing, buffering, automatic slag discharge, and over-limit prevention. The invention greatly reduces the number of gas over-limit times during drilling construction, and effectively avoids gas-coal impact injuries. At the same time, the invention is light and flexible, strong and wear-resistant, has reliable sealing, has the characteristics of good disassembly, and is easy to disassemble and maintain, and is very convenient to match and connect with various drilling rigs, drilling tools and other equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mining, and specifically belongs to coal mine gas control technology, drilling construction protection, and gas over-limit prevention technology. Background Art

[0002] Gas disasters are one of the most important disasters in high-gas mines and coal and gas outburst mines, and are also one of the main bottlenecks restricting their production. In coal seams that do not have the conditions for mining protective layers, pre-extraction of coal seam gas by construction drilling becomes an inevitable choice for mine gas control. During the underground construction of various coal seam drilling holes in high-gas mines, due to the high gas content and high pressure in the coal seams, it is very easy for coal dust and gas in the borehole to be continuously ejected in a short period of time. Once the control measures are not in place, it will cause the high concentration of gas to exceed the limit at the construction site, and the rapidly ejected coal dust will also cause harm to the workers, and there is also a hidden danger of causing gas accidents. Especially for single low-permeability coal seams, the gas extraction efficiency is low. Mines generally adopt hydraulic punching and hydraulic cutting to increase permeability in through-layer drilling to speed up the progress of gas control. Due to the rapid stripping of coal bodies by high-pressure water bodies, a large amount of gas and coal slag are instantly ejected from the borehole under the action of high-pressure water flow, which is very likely to cause short-term gas exceeding the limit near the borehole mouth and gas-coal impact injuries.

[0003] Therefore, during the drilling construction, safety protection measures must be taken to timely extract gas and achieve rapid separation of coal, water and gas. However, the blowout prevention device commonly used in mines at present only places a casing under the hole mouth to connect the blowout prevention device. The casing and the hole wall are not tightly sealed. During the drilling construction, gas continues to gush out from the hole mouth gap; the seal body at the connection between the rear end of the blowout prevention device and the drill rod is subject to the friction of the drill rod rotation and the extrusion of the drilling disturbance, and the gap is easy to further expand, causing the seal to fail. In addition, the slag discharge port of the coal, water and gas separation device is mostly directly open. When the instantaneous gas outflow is large, due to the limited space of the coal, water and gas separation device, the slag discharge port becomes the main channel for gas escape, which greatly reduces the effect of preventing gas from exceeding the limit. At the same time, a large amount of high-pressure gas is desorbed, released and quickly gushes out, causing an impact on the overall protection device for drilling operations. In summary, the devices currently used in mines have a relatively single function, large size, heavy weight, poor sealing effect, and unsatisfactory protection effect. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned existing devices, the present invention provides a lightweight, flexible, sturdy, wear-resistant and reliably sealed sealing and buffering anti-overlimit protection system for drilling construction operations, which integrates a hole mouth extrusion and expansion sealing device, a coal and water automatic discharge sealing device, and a high-pressure gas pressure reduction buffer device. The system comprehensively prevents gas overlimit during drilling construction and ensures the safety of construction workers.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A sealing and buffering over-limit protection system for underground drilling construction work, comprising an extrusion expansion sealing device of a hole opening, a coal and water automatic discharge sealing device, and a high-pressure gas decompression buffer device, wherein the extrusion expansion sealing device is connected to the coal and water automatic discharge sealing device, and the coal and water automatic discharge sealing device is connected to the high-pressure gas decompression buffer device, wherein the extrusion expansion sealing device comprises a casing and a blowout prevention cavity, wherein a step is provided at the front end of the casing and the outer wall is smooth, an external thread is integrally formed in the middle of the casing, and a fixed thread is provided at the rear end of the casing, wherein a polymer expansion ring, a propulsion cylinder, and a rotating handle are sequentially provided on the outside of the casing, wherein the rotating handle is threadedly connected to the middle part of the casing, and the casing is connected to the blowout prevention cavity through a fixed thread, and the polymer expansion ring, the propulsion cylinder, and the rotating handle are abutted in sequence;

[0007] The automatic coal-water discharge sealing device comprises a coal-water-gas separation box and a rotating sealing cavity. The inlet of the coal-water-gas separation box is connected with the outlet of the blowout prevention cavity. The rotating sealing cavity is arranged at the lower part of the coal-water-gas separation box. A rotating shaft is arranged inside the rotating sealing cavity. A hard rotating blade is arranged on the rotating shaft. A flexible sealing rubber pad is arranged between the rotating blade and the rotating sealing cavity. The flexible sealing rubber pad is wrapped around the rotating blade.

[0008] Furthermore, the upper and lower sides of the blowout prevention cavity are respectively integrally formed with a source extraction port and a water slag conveying port, and the rear end of the blowout prevention cavity is provided with a drill pipe sealing rotating sealing part, and the drill pipe sealing rotating sealing part includes a sealing rubber gasket, an annular brush seal, and a fixed chuck, and the sealing rubber gasket, annular brush seal, and fixed chuck are connected in sequence at the rear end of the blowout prevention cavity.

[0009] Furthermore, the outlet of the sub-source extraction port is connected to a first sub-source extraction pipe, the outlet of the first sub-source extraction pipe is connected to a temporary underground extraction pipeline, the outlet of the water-slag conveying port is connected to a water-slag conveying pipe, and the outlet of the water-slag conveying pipe is connected to the inlet of the coal-water automatic discharge sealing device.

[0010] Furthermore, a source extraction port is integrally formed on the top of the coal-water-gas separation box, the outlet of the source extraction port is connected to a second source extraction pipe, the outlet of the second source extraction pipe is connected to an underground extraction pipeline, and a conical water-slag conveying box is integrally formed on the bottom of the coal-water-gas separation box, a flange is provided at the bottom of the conical water-slag conveying box, and the conical water-slag conveying box is connected to the inlet of the rotating sealing cavity through the flange.

[0011] Furthermore, an outlet on one side of the coal-water-gas separation box is connected to an inlet of a high-pressure gas pressure reducing buffer device. The high-pressure gas pressure reducing buffer device includes a flexible buffer bag and a plurality of hard frames. The hard frames are evenly arranged in the flexible buffer bag. The inlet of the flexible buffer bag is conical, and the flexible buffer bag is made of anti-static and foldable materials.

[0012] Furthermore, there are at least three rotating blades, and the angles formed between them are consistent. A coal-water discharge port is provided at the bottom of the rotating sealing cavity, and the diameter of the coal-water discharge port is not greater than the straight-line distance between the top ends of adjacent rotating blades.

[0013] Furthermore, the rotating blade is provided with a fixing nut, and the flexible sealing rubber pad is fixedly connected to the rotating blade via the fixing nut.

[0014] By adopting the above technical scheme, the beneficial effects of the present invention are as follows: the present invention aims at the locations and characteristics of the spray holes that are prone to spray hole hazards during the drilling construction in coal mines, and provides a drilling construction protection system that integrates the functions of sealing, buffering, automatic slag discharge, and over-limit prevention. The hole mouth extrusion and expansion sealing device ensures the sealing inside the hole by rotating the rotating handle to squeeze the polymer expansion ring, eliminating the source of gas leakage at the hole mouth. It is easy to operate and has a good sealing effect. It adopts a replaceable annular brush seal to achieve a close combination with the drill rod. The coal dust in the borehole is integrated with the brush to improve the sealing performance; the coal-water automatic discharge sealing device adopts a rotating slag discharge system to ensure that the coal, water, and gas in the coal-water gas collecting box will not directly flow into the tunnel. On the basis of ensuring the sealing effect of coal-water-gas separation, it can realize the continuous and automatic discharge of coal dust, water, etc. to the external tunnel; the high-pressure gas reduction The pressure buffer device can be expanded and contracted according to the amount of gas gushing out of the borehole during drilling. Once a large amount of gas is ejected from the hole during drilling, the device can play a temporary buffering role through volume changes. The hard skeleton can prevent the device from being deformed by negative pressure due to the connection of the extraction pipeline, thereby affecting its use. The present invention greatly reduces the number of gas exceeding the limit during drilling construction, and effectively avoids gas-coal impact injuries. At the same time, the present invention is light and flexible, strong and wear-resistant, and has reliable sealing. It has the characteristics of good disassembly and easy disassembly and maintenance, and is very convenient to match and connect with various drilling rigs, drilling tools and other equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the installation and connection of the present invention;

[0016] Figure 2 A schematic cross-sectional view of the orifice extrusion expansion sealing device of the present invention;

[0017] Figure 3 It is a schematic cross-sectional view of the automatic coal-water discharge sealing device of the present invention;

[0018] Figure 4 It is a schematic diagram of fixing the flexible sealing rubber pad of the present invention;

[0019] In the figure: 1. Drill bit; 2. Drill rod; 3. Drilling rig; 4. Casing; 5. Polymer expansion ring; 6. Push cylinder; 7. Rotating handle; 8. Fixed thread; 9. Blowout prevention cavity; 10. Source extraction port; 11. Water slag conveying port; 12. Sealing pad; 13. Annular brush seal; 14. Fixed chuck; 15. First source extraction pipe; 16. Temporary extraction pipe underground; 17. Water slag conveying pipe; 18. Coal-water-gas separation box; 19. Water slag Conveying pipe connection port; 20, source extraction port; 21, coal-water automatic discharge sealing device connection port; 22, slag conveying box; 23, flange; 24, rotating sealing chamber; 25, coal-water discharge port; 26, rotating shaft; 27, rotating blade; 28, flexible sealing pad; 29, fixing nut; 30, flexible conical connection; 31, high-pressure gas pressure reducing buffer device; 32, hard skeleton; 33, second source extraction pipe; 34, underground extraction pipeline. DETAILED DESCRIPTION

[0020] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the present invention is further described below in conjunction with specific implementation methods:

[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. All other embodiments obtained by ordinary technicians in the field based on the embodiments of the present invention without making any creative work are within the scope of protection of the present invention.

[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0023] The terms “first”, “second”, “third”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0024] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly stipulated and limited, the terms "set", "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] Combination Figure 1-4As shown: a sealing buffering and over-limit protection system for underground drilling construction operations, including an extrusion expansion sealing device of the orifice, a coal-water automatic discharge sealing device, and a high-pressure gas decompression buffer device 31, wherein the extrusion expansion sealing device is connected to the coal-water automatic discharge sealing device, and the coal-water automatic discharge sealing device is connected to the high-pressure gas decompression buffer device 31, and the extrusion expansion sealing device includes a casing 4 and a blowout prevention cavity 9, wherein the front end of the casing 4 is provided with a step, and the outer wall is smooth, the middle of the casing 4 is integrally formed with an external thread, and the rear end of the casing 4 is provided with a fixed thread 8, and the outside of the casing 4 is provided with a polymer expansion ring 5, a propulsion cylinder 6, and a rotating handle 7 in sequence, and the rotating handle 7 is threadedly connected to the middle part of the casing 4, and the casing 4 is connected to the blowout prevention cavity 9 through the fixed thread 8, and the polymer expansion ring 5, the propulsion cylinder 6, and the rotating handle 7 are abutted in sequence;

[0026] The automatic coal-water discharge sealing device includes a coal-water-gas separation box 18 and a rotating sealing cavity 24. The inlet of the coal-water-gas separation box 18 is connected to the outlet of the blowout prevention cavity 9. The rotating sealing cavity 24 is arranged at the lower part of the coal-water-gas separation box 18. A rotating shaft 26 is arranged inside the rotating sealing cavity 24. A hard rotating blade 27 is arranged on the rotating shaft 26. A flexible sealing rubber pad 28 is arranged between the rotating blade 27 and the rotating sealing cavity 24. The flexible sealing rubber pad 28 is wrapped around the rotating blade 27.

[0027] In this embodiment, the upper and lower sides of the blowout prevention cavity 9 are respectively integrally formed with a source extraction port 10 and a water slag conveying port 11, and the rear end of the blowout prevention cavity 9 is provided with a drill pipe sealing rotating sealing part, and the drill pipe sealing rotating sealing part includes a sealing rubber pad 12, an annular brush seal 13, and a fixed chuck 14. The sealing rubber pad 12, the annular brush seal 13, and the fixed chuck 14 are connected in sequence at the rear end of the blowout prevention cavity 9.

[0028] In this embodiment, the outlet of the sub-source extraction port 10 is connected to the first sub-source extraction pipe 15, the outlet of the first sub-source extraction pipe 15 is connected to the underground temporary extraction pipe 16, the outlet of the water-slag conveying port 11 is connected to the water-slag conveying pipe 17, and the outlet of the water-slag conveying pipe 17 is connected to the inlet of the coal-water automatic discharge sealing device.

[0029] In this embodiment, a source extraction port 20 is integrally formed on the top of the coal-water-gas separation box 18, and the outlet of the source extraction port 20 is connected to a second source extraction pipe 33, and the outlet of the second source extraction pipe 33 is connected to an underground extraction pipe 34. A conical water-slag conveying box 22 is integrally formed on the bottom of the coal-water-gas separation box 18, and a flange 23 is provided at the bottom of the conical water-slag conveying box 22, and the conical water-slag conveying box 22 is connected to the inlet of the rotating sealing cavity 24 through the flange 23.

[0030] In this embodiment, the outlet on one side of the coal-water-gas separation box 18 is connected to the inlet of the high-pressure gas pressure reducing buffer device 31. The high-pressure gas pressure reducing buffer device 31 includes a flexible buffer bag and a plurality of hard skeletons 32. The hard skeletons 32 are evenly arranged in the flexible buffer bag. The inlet of the flexible buffer bag is conical, and the flexible buffer bag is made of anti-static and foldable materials.

[0031] In this embodiment, there are at least three rotating blades 27 , and the angles formed between them are consistent. A coal-water discharge port 25 is provided at the bottom of the rotating sealing cavity 24 , and the diameter of the coal-water discharge port 25 is not greater than the straight-line distance between the tops of adjacent rotating blades 27 .

[0032] In this embodiment, a fixing nut 29 is provided on the rotating blade 27 , and the flexible sealing rubber pad 28 is fixedly connected to the rotating blade 27 via the fixing nut 29 .

[0033] In the embodiment of the present invention, the specific implementation steps of the sealing buffer overrun protection system for underground drilling construction operations are as follows:

[0034] Before drilling construction, send the hole mouth extrusion expansion sealing device into the pre-drilled hole, turn the rotary handle 7 to push the thrust cylinder 6 forward, so that the thrust cylinder 6 abuts and squeezes the polymer expansion ring 5, causing it to expand and closely contact the hole wall. Connect the first sub-source extraction port 10 with the underground temporary extraction pipe 16 through the sub-source extraction pipe 15, connect the water slag conveying port 11 with the coal-water automatic discharge sealing device through the water slag conveying pipe 17, connect the water slag conveying pipe connection port 19 with the hole mouth extrusion expansion sealing device water slag conveying port 11 through the water slag conveying pipe 17, connect the second sub-source extraction port 20 with the underground extraction pipeline 34 through the sub-source extraction pipe 33, and connect the high-pressure gas pressure reduction buffer device 31 with the coal-water automatic discharge sealing device connection port 21 through the flexible conical connection 30;

[0035] Through the above steps, the fixed installation is completed, and the drilling rig 3 is operated to pass the drill bit 1 and the drill rod 2 through the hole extrusion expansion sealing device for drilling construction; during the drilling construction and hydraulic punching and permeability enhancement, the polymer expansion ring 5 of the front extrusion expansion sealing part of the hole extrusion expansion sealing device is in close contact with the hole wall, blocking the gap of the borehole mouth to prevent gas from pouring into the tunnel, and the sealing pad 12 and the annular brush seal 13 of the rear end drill rod rotation sealing part are combined to achieve a close combination with the drill rod during the rotary drilling of the drill rod, and the coal dust in the borehole is integrated with the brush to improve the sealing performance; part of the gas in the borehole is sucked into the underground temporary extraction pipe 16 through the first source extraction port 10, and the coal, water and part of the gas in the hole enter the coal-water automatic discharge sealing device through the water slag conveying port 11; the gas in the coal-water automatic discharge sealing device is sucked into the underground extraction pipeline 34 through the second source extraction port 20, and when the instantaneous gas outflow of the borehole is When the gas pressure is relatively large, the gas enters the high-pressure gas pressure reducing buffer device 31 through the connection port 21 of the coal-water automatic discharge sealing device. The high-pressure gas pressure reducing buffer device 31 can expand and contract according to the amount of gas gushing out of the borehole during drilling, and plays a temporary buffering role through volume change. The hard skeleton 32 prevents the device from being deformed by the negative pressure due to the connection of the extraction pipeline, thereby affecting the use; the coal-water mixture enters the rotary sealing cavity 24 through the conical water-slag conveying box 22, and the hard rotating blade 27 is driven by gravity to rotate to the lower coal-water discharge port 25 and discharged from the device; the inside of the rotary sealing device is divided into three relatively independent spaces by the hard rotating blade 27 and the flexible sealing rubber pad 28. During the rotation of the hard rotating blade 27, it is always ensured that there is at least one scraper to separate the cavity between the upper inlet and the lower coal-water discharge port 25, so as to keep the coal-water-gas separation device in a closed state.

[0036] This embodiment does not impose any formal limitation on the shape, material, structure, etc. of the present invention. Any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0037] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A sealing and buffering anti-overrun protection system for underground drilling operations, comprising an orifice extrusion expansion sealing device, a coal-water automatic discharge sealing device, and a high-pressure gas decompression buffer device, wherein the extrusion expansion sealing device is connected to the coal-water automatic discharge sealing device, and the coal-water automatic discharge sealing device is connected to the high-pressure gas decompression buffer device, characterized in that: The extrusion expansion sealing device comprises a sleeve and a blowout prevention cavity. The front end of the sleeve is provided with a step and the outer wall is smooth. The middle of the sleeve is integrally formed with an external thread. The rear end of the sleeve is provided with a fixed thread. The outside of the sleeve is provided with a polymer expansion ring, a propulsion cylinder, and a rotating handle in sequence. The rotating handle is threadedly connected to the middle of the sleeve. The sleeve is connected to the blowout prevention cavity through a fixed thread. The polymer expansion ring, the propulsion cylinder, and the rotating handle are abutted in sequence. The automatic coal-water discharge sealing device comprises a coal-water-gas separation box and a rotary sealing cavity. The inlet of the coal-water-gas separation box is connected to the outlet of the blowout prevention cavity. The rotary sealing cavity is arranged at the lower part of the coal-water-gas separation box. A rotary shaft is arranged inside the rotary sealing cavity. A hard rotary blade is arranged on the rotary shaft. A flexible sealing rubber pad is arranged between the rotary blade and the rotary sealing cavity. The flexible sealing rubber pad is wrapped around the rotary blade. There are at least three rotating blades, and the angles formed between them are consistent. A coal-water discharge port is provided at the bottom of the rotating sealing cavity, and the diameter of the coal-water discharge port is not greater than the straight-line distance between the top ends of adjacent rotating blades; The upper and lower sides of the blowout prevention cavity are respectively integrally formed with a source extraction port and a water slag conveying port. The rear end of the blowout prevention cavity is provided with a drill pipe sealing rotating sealing part, and the drill pipe sealing rotating sealing part includes a sealing rubber pad, an annular brush seal, and a fixed chuck. The sealing rubber pad, annular brush seal, and fixed chuck are connected in sequence at the rear end of the blowout prevention cavity.

2. The sealing, buffering and over-limit protection system for underground drilling operations according to claim 1 is characterized in that: The outlet of the sub-source extraction port is connected to a first sub-source extraction pipe, the outlet of the first sub-source extraction pipe is connected to a temporary underground extraction pipeline, the outlet of the water-slag conveying port is connected to a water-slag conveying pipe, and the outlet of the water-slag conveying pipe is connected to the inlet of the coal-water automatic discharge sealing device.

3. The sealing, buffering and over-limit protection system for underground drilling operations according to claim 1 is characterized in that: A source extraction port is integrally formed on the top of the coal-water-gas separation box, and the outlet of the source extraction port is connected to a second source extraction pipe, and the outlet of the second source extraction pipe is connected to an underground extraction pipeline. A conical water-slag conveying box is integrally formed on the bottom of the coal-water-gas separation box, and a flange is provided at the bottom of the conical water-slag conveying box, and the conical water-slag conveying box is connected to the inlet of the rotating sealing cavity through the flange.

4. The sealing, buffering and over-limit protection system for underground drilling operations according to claim 1 is characterized in that: The outlet on one side of the coal-water-gas separation box is connected to the inlet of the high-pressure gas decompression buffer device. The high-pressure gas decompression buffer device includes a flexible buffer bag and a plurality of hard frames. The hard frames are evenly arranged in the flexible buffer bag. The inlet of the flexible buffer bag is conical, and the flexible buffer bag is made of anti-static and foldable materials.

5. The sealing, buffering and over-limit protection system for underground drilling operations according to claim 1 is characterized in that: The rotating blade is provided with a fixing nut, and the flexible sealing rubber pad is fixedly connected to the rotating blade through the fixing nut.

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