Directional long drill hole bidirectional hydraulic slotting device and method

Abstract

The invention relates to the field of coal mine gas extraction, in particular to a directional long-drilling bidirectional hydraulic slotting device which comprises a drilling machine with advancing or retreating propelling capacity. The tail end of the high-pressure water conveying drill rod is connected to a drilling machine, and a channel is formed in the high-pressure water conveying drill rod. The motor is fixedly arranged at the front end of the high-pressure water conveying drill rod, a drill bit axial water outlet is formed in the front end of the cutting drill bit, and the output end of the motor faces the front of the high-pressure water conveying drill rod. The cutting drill bit is installed at the output end of the motor, and a slotting water outlet is formed in the periphery of the cutting drill bit. The high-pressure water conveying device is connected into the high-pressure water conveying drill rod and used for conveying high-pressure water to the cutting drill bit. According to the directional long drill hole two-way hydraulic slotting device, high-pressure water is used as impact power, a plurality of flat slots are formed in a coal body on the wall of a drill hole, and good conduction conditions are created for internal pressure relief, gas release and flowing of a coal seam through the slots.

Description

Technical Field

[0001] The present invention relates to the field of coal mine gas extraction, and is a directional long borehole bidirectional hydraulic slitting device and method. Background Art

[0002] With the continuous deepening of coal mining in my country, gas disaster management is particularly important. As a traditional means of gas management, pre-extraction of coal seam gas by drilling holes faces many challenges in deep mining. Due to the gradual increase in coal seam gas pressure and gas content and the gradual decrease in coal seam permeability, the pre-extraction effect is often not ideal, which manifests as low concentration and rapid attenuation of gas. Therefore, improving the permeability of coal seams through hydraulic cutting has become an important means to solve gas management. The existing hydraulic cutting method often requires the replacement of the drill bit during the drilling process and only has one type of backward cutting, which is not only time-consuming and labor-intensive, but also may face problems such as hole collapse and top drilling when re-drilling. Summary of the invention

[0003] In order to solve the above problems, the present invention proposes a directional long-hole bidirectional hydraulic slitting device, which can realize the forward or backward bidirectional drilling and cutting integrated slitting technology, and use high-pressure water as the impact power to form a plurality of flat slits in the coal (rock) body of the borehole wall, and create good conduction conditions for internal pressure relief, gas release and flow of the coal seam through the slits. The present invention is a hydraulic slitting method that uses forward or backward drilling and cutting to cut a plurality of flat slits in the coal (rock) of the borehole wall as a protective layer in a local area, increase the permeability of the coal body near the slit, and cause the coal body near the slit to shift toward the slit, thereby expanding the range of slit pressure relief and permeability enhancement, and gas emission, and providing effective facility guarantees for ensuring the efficient extraction of coal seam gas and achieving the purpose of preventing outbursts and increasing permeability.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] In the first technical solution, a directional long hole bidirectional hydraulic slotting device is characterized by: comprising

[0006] A drilling rig having a forward or reverse propulsion capability;

[0007] A high-pressure water delivery drill pipe, the tail end of which is connected to the drilling rig, and the high-pressure water delivery drill pipe has a channel inside;

[0008] A motor, wherein the motor is fixed at the front end of the high-pressure water delivery drill pipe, the front end of the cutting drill bit has an axial water outlet of the drill bit, and the output end of the motor faces the front of the high-pressure water delivery drill pipe;

[0009] A cutting drill bit, the cutting drill bit is installed at the output end of the motor, and a cutting water outlet is opened at the outer periphery of the cutting drill bit;

[0010] A high-pressure water delivery device is connected to the inside of the high-pressure water delivery drill rod and is used to deliver high-pressure water to the cutting drill bit.

[0011] In the first technical solution, preferably, the high-pressure water delivery device includes a high-pressure pump, a high-pressure hose and a high-pressure water transformer, wherein the high-pressure water transformer is installed on the high-pressure water delivery drill pipe, and the output end of the high-pressure pump is connected to the input end of the high-pressure water transformer through a high-pressure hose.

[0012] In the first technical solution, preferably, the high-pressure pump further comprises a pressure gauge for detecting the internal pressure of the high-pressure pump and a water pressure gauge for detecting the pressure of the water flow output by the high-pressure pump.

[0013] In a second technical solution, a directional long borehole bidirectional hydraulic slotting method is provided, using a directional long borehole bidirectional hydraulic slotting device as described in any one of the first technical solutions, the method comprising:

[0014] When cutting and punching coal seams, the drilling rig provides forward or backward drilling power. During normal drilling, the high-pressure water supply drill pipe is connected to the high-pressure water transformer, and the axial water outlet of the cutting drill bit discharges water normally, and the drilling is carried out to the designed cutting depth; the high-pressure water supply drill pipe is connected to the high-pressure water transformer to apply high-pressure rotating water transformer, and the high-pressure pump provides a pressure head of ≥80MPa as impact power. The high-pressure pump and the high-pressure water transformer are connected through a high-pressure hose and cooperate with each other to deliver high-pressure water to the high-pressure water supply drill pipe. The drilling rig rotates at a uniform speed to drive the integrated drilling and cutting drill bit to rotate. After the high-pressure pump is turned on, the axial water outlet of the cutting drill bit is closed, and the cutting outlet is opened. The radial high-pressure water jet is used to cut the coal wall for 5 to 10 minutes.

[0015] In the second technical solution, as a preferred method, during the cutting and punching process, the cutting and punching forms equidistant gaps with a spacing of 30m, a radius of 0.5-1m, a crack width of 15-30mm in the coal seam, and a directional long drill hole with a hole depth of not less than 300m.

[0016] In the second technical solution, as a preferred embodiment, the directional long drilling for slitting and punching is constructed in accordance with the existing technical regulations. After the drilling is completed, all the holes need to be sealed in accordance with the regulations. The sealing depth is not less than 16m, and the relevant monitoring instruments are connected.

[0017] In the second technical solution, as a preferred method, before slitting and punching are carried out in the coal seam, two drilling sites are arranged in the coal seam, and 10 directional long drill holes are constructed in the two drilling sites. Slitting and punching are carried out on 5 directional long drill holes in the first drilling site, and slitting and punching are carried out on 5 directional long drill holes in the second drilling site as comparison holes.

[0018] In the second technical solution, as a preferred option, after the construction of the two drilling sites is completed, the engineering time consumed and the hole-making effect of the two drilling sites are recorded to determine whether the hydraulic cutting is tighter in process connection and the hole is formed in one time, and the equipment is more stable and effective. On-site tests compare and analyze the effective impact radius of drilling and extraction with cutting and punching drilling and drilling without cutting and punching.

[0019] The beneficial effects of using the present invention are:

[0020] At present, the method for hydraulic slitting of long boreholes is to replace the hydraulic slitting drill bit for backward cutting when drilling to the cutting position, which is not only time-consuming and labor-intensive, but also may face problems such as hole collapse and top drilling when re-drilling. In response to this problem, a directional long borehole bidirectional hydraulic slitting device is designed, which can realize the slitting technology of forward or backward bidirectional drilling and cutting. It uses high-pressure water as impact power to sweep the coal body and discharge slag, so that multiple flat slits are formed in the coal (rock) body of the borehole wall, thereby improving the permeability of the coal seam and expanding the influence radius of the drilling extraction, so as to achieve the purpose of extracting coal seam gas in a short time and efficiently, and achieve the purpose of preventing outbursts and increasing permeability. It avoids manual replacement of drill bits and one-way slitting drilling, improves the effectiveness and diversity of hydraulic slitting, and can produce obvious economic and social benefits. It has broad application prospects in improving the permeability of coal seams in high-gas and outburst mines and expanding the influence radius of drilling extraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of a bidirectional hydraulic cutting device and method for directional long drilling in a mine

[0022] Reference numerals include:

[0023] 1-drilling rig; 2-high-pressure water delivery drill pipe; 3-high-pressure pump; 4-pressure gauge; 5-water pressure gauge; 6-high-pressure hose; 7-high-pressure water transformer; 8-motor; 9-slit water outlet; 10-drill bit axial water outlet; 11-cutting drill bit; 12-rock layer; 13-coal layer; 14-directional long drilling. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the technical solution more clear, the technical solution is further described in detail below in conjunction with specific implementation methods. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the technical solution.

[0025] In order to solve the problems in the prior art that the hydraulic cutting method is time-consuming and labor-intensive during the drilling process and re-drilling may also face the problems of hole collapse and top drilling, such as Figure 1As shown, this embodiment proposes a bidirectional hydraulic slitting device for directional long drilling 14, including a drilling rig 1, which has the ability to propel forward or backward; the tail end of a high-pressure water-transmitting drill pipe 2 is connected to the drilling rig 1, and a channel is provided inside the high-pressure water-transmitting drill pipe 2; a motor 8 is fixed at the front end of the high-pressure water-transmitting drill pipe 2, and a drill bit axial water outlet 10 is provided at the front end of the cutting drill bit 11, and the output end of the motor 8 faces the front of the high-pressure water-transmitting drill pipe 2; the cutting drill bit 11 is installed at the output end of the motor 8, and a slitting water outlet 9 is provided at the outer periphery of the cutting drill bit 11; a high-pressure water delivery device is connected to the inside of the high-pressure water-transmitting drill pipe 2, and is used to deliver high-pressure water to the cutting drill bit 11.

[0026] This directional long borehole 14 bidirectional hydraulic cutting device is mostly used in high-gas mines and outburst mines to improve the permeability of coal seams 13 and expand the impact radius of drilling and extraction, so as to achieve short-term and efficient extraction of coal seam 13 gas, thereby achieving the purpose of preventing outbursts and increasing permeability. Among them, the high-pressure pump 3 can provide a pressure head of ≥80MPa as impact power. When drilling to the required position, the motor 8 provides a rotation speed and torque to drive the drill bit to rotate and cut the coal seam 13, without the need for the drill rod to rotate. When the drilling rig 1 is performing a cutting operation, the drilling rig 1 only acts as a propulsion rotator, and there is no need to improve the performance and structure of the drilling rig 1. The high-pressure hose 6 connects the high-pressure pump 3 and the high-pressure water transformer, and the three cooperate with each other to deliver high-pressure water to the Φ73mm high-pressure water supply drill rod 2.

[0027] Preferably, the high-pressure water delivery device comprises a high-pressure pump 3, a high-pressure hose 6 and a high-pressure water transformer, wherein the high-pressure water transformer is installed on the high-pressure water delivery drill pipe 2, and the output end of the high-pressure pump 3 is connected to the input end of the high-pressure water transformer through the high-pressure hose 6. The high-pressure pump 3 also has a pressure gauge 4 for detecting the internal pressure of the high-pressure pump 3, and a water pressure gauge 5 for detecting the output water flow pressure of the high-pressure pump 3.

[0028] The directional long hole 14 bidirectional hydraulic slotting device uses forward or backward drilling mode, and the integrated drilling and cutting drill bit uses high-pressure water as impact power to perform backward or forward sweeping circle cutting and slag removal on the coal (rock) body, forming multiple flat slots in the coal (rock) body. Through slots and cracks, pressure relief and permeability enhancement are achieved, and the range of gas emission is expanded. It avoids manual replacement of drill bits and one-way slotting drilling methods, improves the effectiveness and diversity of hydraulic slotting, ensures efficient extraction of coal seam 13 gas, and achieves the purpose of preventing bursts and increasing permeability.

[0029] A pressure relief borehole is constructed in the coal (rock) layer using a drilling and cutting integrated drill bit. During the drilling process, high-pressure hydraulic power is used to perform forward equidistant sweeping circle cutting of the coal (rock) body along the hole wall, or backward equidistant sweeping circle cutting is performed when drilling to the cutting position, forming multiple flat seams in the vertical drilling direction. The seams can enhance the permeability of the coal body, create good conduction conditions for pressure relief, gas release, and flow inside the coal seam 13, and achieve the purpose of eliminating bursts and increasing permeability. Multiple flat seams are mainly formed by high-pressure hydraulic power cutting the coal wall in the borehole warp direction to form multiple equidistant flat seams. The flat seams are equivalent to mining a very thin protective layer in the local range of the coal rock body, causing the coal body near the seams to displace toward the seams, expanding the seam pressure relief and permeability enhancement, and gas emission range, thereby improving the permeability of the coal seam 13, and expanding the impact radius of the drilling extraction, achieving the purpose of extracting gas from the coal seam 13 in a short time and efficiently.

[0030] This embodiment also proposes a bidirectional hydraulic slotting method for a directional long borehole 14, using the above-mentioned bidirectional hydraulic slotting device for a directional long borehole 14, comprising the following steps:

[0031] Take a coal seam 13 in a certain mine as an example. When it is found that the permeability of the coal seam 13 is low and the pre-extraction effect is not ideal, the permeability of the coal seam 13 can be improved by hydraulic slotting, and the radius of drilling extraction can be expanded to achieve short-term and efficient extraction of gas from the coal seam 13. First, it is planned to arrange two drilling sites in the coal seam 13, and construct 10 directional long boreholes 14 in the two drilling sites. The 5 directional long boreholes 14 in the first drilling site are slotted and punched, and the 5 directional long boreholes 14 in the second drilling site are used as comparison holes without slotting and punching.

[0032] When performing slitting and punching, the drilling rig 1 provides forward or backward drilling power. During normal drilling, the operation mode remains unchanged, the Φ73mm high-pressure water supply drill pipe 2 is connected to the rotating water variable, and the axial water outlet 10 of the cutting drill bit 11 discharges water normally. After drilling to the designed cutting depth, the Φ73mm high-pressure water supply drill pipe 2 is connected to the high-pressure water variable to apply high-pressure rotating water variable, and the high-pressure pump 3 provides a pressure head of ≥80MPa as impact power. The high-pressure pump 3 and the high-pressure water variable are connected through a high-pressure hose 6 and cooperate with each other to deliver high-pressure water to the Φ73mm high-pressure water supply drill pipe 2. The drilling rig 1 rotates at a uniform speed to drive the integrated drilling and cutting drill bit to rotate. After the high-pressure pump 3 is turned on, the axial water outlet 10 of the cutting drill bit 11 is closed, and the radial high-pressure water jet nozzle (slit water outlet 9) is turned on. The radial high-pressure water jet is cut on the coal wall for 5 to 10 minutes.

[0033] After cutting and punching, equidistant gaps with a spacing of 30m, a radius of 0.5-1m, a crack width of 15-30mm, and a directional long borehole 14 with a hole depth of not less than 300m will be formed in the coal seam 13. During the cutting process, the pressure gauge 4 and the water pressure gauge 5 can display the pressure head in the high-pressure pump 3 and the high-pressure hose 6 in real time. The directional long borehole 14 without slitting and punching is constructed in accordance with the existing technical regulations. After the drilling is completed, all boreholes need to be sealed in accordance with regulations. The sealing depth is not less than 16m, and relevant monitoring instruments are connected. On-site inspection of the extraction effect of 5 directional long boreholes 14 and 5 slit punching boreholes;

[0034] The engineering time consumed and the drilling effect of the two drilling sites were recorded to determine whether hydraulic cutting was more closely connected in process and drilling was more one-time, and whether the equipment was more stable and effective. On-site tests were conducted to compare and analyze the effective impact radius of drilling with cutting and punching and drilling without cutting and punching.

[0035] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. This specification is only for a coal seam 13 in a certain mine, and the rock layer 12 above the coal seam 13 is capped. The specific construction parameters (such as gap spacing, dwell cutting time, pressure, etc.) can be adjusted according to actual conditions.

[0036] It should be noted that, in the description of the present invention, unless otherwise specified, the meaning of "multiple" is two or more; the orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. At the same time, in the description of the present invention, unless otherwise clearly specified and limited, the terms "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 directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0037] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, many changes can be made in the specific implementation methods and application scopes based on the ideas of the present technical content. As long as these changes do not deviate from the concept of the present invention, they all fall within the scope of protection of this patent.

Claims

1. A directional long hole bidirectional hydraulic slotting device, characterized in that: include A drilling rig having a forward or reverse propulsion capability; A high-pressure water delivery drill pipe, the tail end of which is connected to the drilling rig, and the high-pressure water delivery drill pipe has a channel inside; A motor, wherein the motor is fixed at the front end of the high-pressure water delivery drill pipe, the front end of the cutting drill bit has an axial water outlet of the drill bit, and the output end of the motor faces the front of the high-pressure water delivery drill pipe; A cutting drill bit, the cutting drill bit is installed at the output end of the motor, and a cutting water outlet is opened at the outer periphery of the cutting drill bit; A high-pressure water delivery device is connected to the inside of the high-pressure water delivery drill rod and is used to deliver high-pressure water to the cutting drill bit.

2. The directional long hole drilling bidirectional hydraulic slotting device according to claim 1 is characterized in that: The high-pressure water delivery device includes a high-pressure pump, a high-pressure hose and a high-pressure water transformer, wherein the high-pressure water transformer is installed on the high-pressure water delivery drill pipe, and the output end of the high-pressure pump is connected to the input end of the high-pressure water transformer through a high-pressure hose.

3. The directional long hole bidirectional hydraulic slotting device according to claim 2 is characterized in that: The high-pressure pump also has a pressure gauge for detecting the internal pressure of the high-pressure pump and a water pressure gauge for detecting the pressure of the water flow output by the high-pressure pump.

4. A directional long hole bidirectional hydraulic slotting method, using the directional long hole bidirectional hydraulic slotting device according to any one of claims 1 to 3, characterized in that: The method comprises: When cutting and punching coal seams, the drilling rig provides forward or backward drilling power. During normal drilling, the high-pressure water supply drill pipe is connected to the high-pressure water transformer, and the axial water outlet of the cutting drill bit discharges water normally, and the drilling is carried out to the designed cutting depth; the high-pressure water supply drill pipe is connected to the high-pressure water transformer to apply high-pressure rotating water transformer, and the high-pressure pump provides a pressure head of ≥80MPa as impact power. The high-pressure pump and the high-pressure water transformer are connected through a high-pressure hose and cooperate with each other to deliver high-pressure water to the high-pressure water supply drill pipe. The drilling rig rotates at a uniform speed to drive the integrated drilling and cutting drill bit to rotate. After the high-pressure pump is turned on, the axial water outlet of the cutting drill bit is closed, and the cutting outlet is opened. The radial high-pressure water jet is used to cut the coal wall for 5 to 10 minutes.

5. The method for bidirectional hydraulic slotting of directional long drilling according to claim 4 is characterized in that: During the cutting and punching process, cutting and punching form equidistant gaps with a spacing of 30m, a radius of 0.5-1m, a crack width of 15-30mm, and a directional long drill hole with a hole depth of not less than 300m in the coal seam.

6. The method for bidirectional hydraulic slotting of directional long drilling according to claim 4 is characterized in that: The directional long drilling for slitting and punching is constructed in accordance with the existing technical regulations. After the drilling is completed, all the holes need to be sealed in accordance with the regulations. The sealing depth shall not be less than 16m, and the relevant monitoring instruments shall be connected.

7. The method for bidirectional hydraulic slotting of a directional long hole according to claim 4, characterized in that: Before slitting and punching are carried out in the coal seam, two drilling sites are arranged in the coal seam. Ten directional long boreholes are constructed in the two drilling sites. Five directional long boreholes in the first drilling site are subjected to slitting and punching, and the five directional long boreholes in the second drilling site are used as comparison holes without slitting and punching.

8. The method for bidirectional hydraulic slotting of a directional long hole according to claim 7, characterized in that: After the construction of the two drilling sites was completed, the engineering time and hole-making results consumed by the two drilling sites were recorded to determine whether the hydraulic cutting was more closely connected in the process and the hole was formed in one time, and whether the equipment was more stable and effective. The on-site test compared and analyzed the effective impact radius of drilling with cutting and punching and drilling without cutting and punching.

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