CN113738270B - Directional drilling device and method for pre-weakened coal rock induced mechanical drilling - Google Patents
Directional drilling device and method for pre-weakened coal rock induced mechanical drilling Download PDFInfo
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- CN113738270B CN113738270B CN202110857304.XA CN202110857304A CN113738270B CN 113738270 B CN113738270 B CN 113738270B CN 202110857304 A CN202110857304 A CN 202110857304A CN 113738270 B CN113738270 B CN 113738270B
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- 238000005553 drilling Methods 0.000 title claims abstract description 96
- 239000003245 coal Substances 0.000 title claims abstract description 57
- 239000011435 rock Substances 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims abstract description 16
- 230000006698 induction Effects 0.000 claims description 7
- 230000003313 weakening effect Effects 0.000 description 9
- 238000010586 diagram Methods 0.000 description 4
- 238000000605 extraction Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000005299 abrasion Methods 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009933 burial Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001066 destructive effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009532 heart rate measurement Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B44/00—Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
- E21B7/04—Directional drilling
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
Abstract
The invention discloses a directional drilling device and a directional drilling method for pre-weakened coal rock induced mechanical drilling. The mechanical drilling system comprises a drilling machine, an auger stem and a drill bit. The plasma discharge system includes a plasma generator, a positive electrode, a negative electrode, and an insulating plate. The directional control system comprises a hydraulic pushing rod controller, a hydraulic pushing rod, a rotating shaft controller and an electric rotating shaft. The invention utilizes the rotating shaft control system to drive the positive electrode and the negative electrode to rotate, so that the electrodes and the coal rock wall surface form different discharge angles, further mechanical drilling is induced, and the problem of difficult control of the long-distance drilling direction can be effectively solved.
Description
Technical Field
The invention relates to the field of directional drilling of long-distance drilling in a coal rock body, in particular to a directional drilling device and a directional drilling method for pre-weakening coal rock induced mechanical drilling.
Background
The coal seam burial conditions in China are complex and changeable, most mines have the typical characteristics of high gas pressure, high ground stress, high temperature and low permeability, accurate extraction of gas by using drill holes is one of important ways for solving coal mine gas disasters, and directional and controllable drilling of the drill holes can provide an efficient way for gas extraction.
In recent years, in order to solve the directional drilling problem of long-distance drilling, related scholars develop a comb-shaped drilling directional drilling technology, a mud pulse measurement while drilling directional drilling technology, an electromagnetic wave measurement while drilling air directional drilling technology and the like, the drilling depth and the pore-forming rate are improved to a certain extent, but the methods still have the problems that the drilling direction is difficult to control and the positioning is inaccurate in the drilling process, so that the gas extraction effect is poor.
Therefore, the invention provides a directional drilling device and a directional drilling method for plasma pre-weakened coal rock induced mechanical drilling aiming at the problems, so as to overcome the defects in the existing drilling method.
Disclosure of Invention
The invention aims to solve the technical problems of the prior art and provides a directional drilling device and a directional drilling method for inducing mechanical drilling by pre-weakening coal rock.
In order to solve the technical problems, the invention adopts the technical scheme that:
a directional drilling device for pre-weakening coal rock induction mechanical drilling comprises a mechanical drilling system, a plasma discharge system and a directional control system.
The mechanical drilling system comprises a drilling machine, an auger stem and a drill bit.
One end of the spiral drill rod is connected with the drilling machine, and the other end of the spiral drill rod is connected with the drill bit.
The plasma discharge system includes a plasma generator, a positive electrode, a negative electrode, and an insulating plate.
The positive electrode, the negative electrode and the insulating plate are arranged inside the drill bit; the positive electrode and the negative electrode are arranged in parallel and fixed on the insulating plate.
The plasma discharge system further comprises a positive electrode cable and a negative electrode cable which are arranged inside the spiral drill rod.
The positive end of the plasma generator is connected with the positive electrode through a positive electrode cable; the negative end of the plasma generator is connected with the negative electrode through a negative electrode cable.
The directional control system comprises a hydraulic pushing rod controller, a hydraulic pushing rod, a rotating shaft controller and an electric rotating shaft.
The hydraulic pushing rod is arranged inside the spiral drill rod; one end of the hydraulic pushing rod is connected with the insulating plate, and the other end of the hydraulic pushing rod is connected with the hydraulic pushing rod controller.
The electric rotating shaft is arranged on the hydraulic pushing rod; the rotating shaft controller is connected with the electric rotating shaft.
Preferably, the plasma discharge system further comprises a high-voltage discharge switch arranged between the positive terminal and the positive electrode of the plasma generator.
Preferably, a positive electrode cable hole for laying a positive electrode cable and a negative electrode cable hole for laying a negative electrode cable are arranged in the spiral drill rod.
Preferably, as an improvement of the invention, an electrode movable cavity is arranged in the drill bit.
As an improvement and optimization of the invention, the angle range of the rotation of the electric rotating shaft control electrode in the orientation control system is-90 degrees.
A directional drilling method for pre-weakening coal rock induction mechanical drilling comprises the following steps:
s1, operating a hydraulic push rod controller, controlling a hydraulic push rod, and drilling in the coal rock to a certain distance;
s2, operating a rotating shaft controller, and controlling the electric rotating shaft to enable the positive electrode and the negative electrode to form a drilling angle with the target coal rock wall surface, wherein the angle range is-90 degrees;
s3, starting the plasma generator, and closing the high-voltage discharge switch;
s4, the plasma discharge system discharges the wall surface of the coal rock for multiple times to form cracks with communicated cracks, and pre-weakened coal rock is formed between the positive electrode and the negative electrode;
and S5, the auger stem drives the drill bit to follow the drilling direction of the positive electrode and the negative electrode, and the weakened coal rock interface is continuously drilled to realize directional drilling.
The invention has the following beneficial effects:
1. the device realizes the contact of the discharge electrode and the coal rock wall surface at different angles by operating the hydraulic control system and the rotating shaft control system, then utilizes the directional discharge of the plasma, shock waves and expansion stress with the order of magnitude of several to dozens of megapascals can be generated in the channel in the plasma discharge process under different voltages, the acting force acts on the coal rock wall surface, and pre-weakened coal rock mass is formed between the positive electrode and the negative electrode, so that weak surfaces at different angles are realized in front of a drill hole, the mechanical drilling direction is induced, and the directional drilling is realized.
2. By pre-weakening the coal rock mass, the strength of the coal rock mass is reduced, the abrasion of the mechanical drill bit is effectively reduced, and the service life of the drill bit is prolonged.
3. The method is simple to operate, safe and reliable, effectively solves the problems of large resistance and difficult direction control of long-distance drilling, provides an effective way for gas extraction, and has wide practical value in the technical field.
Drawings
FIG. 1 is a schematic structural diagram of a directional drilling device for induced mechanical drilling of pre-weakened coal rocks according to the invention.
Fig. 2 is a schematic long-distance straight drilling diagram of the directional drilling device for pre-weakened coal rock induced mechanical drilling.
Fig. 3 is a schematic diagram of a directional drilling device for induced mechanical drilling of pre-weakened coal rocks according to the invention in an angular inclined drilling state 1.
Fig. 4 is a schematic diagram of a directional drilling device for induced mechanical drilling of pre-weakened coal rocks according to the invention in an angled inclined drilling state 2.
Among them are: 10. a mechanical drilling system; 11. a drilling machine; 12. a auger stem; 13. a drill bit; 131. an electrode active cavity; 20. a plasma discharge system; 21. a plasma generator; 22. a positive electrode; 23. a negative electrode; 24. an insulating plate; 25. a positive electrode cable; 251. a positive electrode cable hole; 26. a negative electrode cable; 261. a negative electrode cable hole; 27. a high voltage discharge switch; 30. a directional control system; 31. a hydraulic push rod controller; 32. a hydraulic push rod; 33. a rotating shaft controller; 34. an electric rotating shaft.
Detailed Description
The present invention will be described in further detail with reference to the drawings and specific preferred embodiments.
In the description of the present invention, it is to be understood that the terms "left side", "right side", "upper part", "lower part", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and that "first", "second", etc., do not represent an important degree of the component parts, and thus are not to be construed as limiting the present invention. The specific dimensions used in the present example are only for illustrating the technical solution and do not limit the scope of protection of the present invention.
A directional drilling device for pre-weakening coal rock induction mechanical drilling comprises a mechanical drilling system 10, a plasma discharge system 20 and a directional control system 30.
The plasma discharge system 20 can provide 0-200 kJ electric energy and can instantly apply huge electric energy on the wall surface of the coal rock through the discharge electrode, the plasma discharge system 20 is connected with the mechanical drilling system 10 so as to weaken the strength of the coal rock by utilizing strong destructive power generated by plasma discharge, the directional control system 30 is connected to the plasma discharge system 20, the directional control system 30 is utilized to realize control of different angles of the electrode and the coal rock interface, and the coal rock is directionally weakened.
As shown in fig. 1, mechanical drilling system 10 includes a drill 11, an auger stem 12, and a drill bit 13.
The auger stem 12 is connected at one end to the drill 11 and at the other end to the drill bit 13.
An electrode active cavity 131 is provided in the drill bit 13.
The plasma discharge system 20 includes a plasma generator 21, a positive electrode 22, a negative electrode 23, and an insulating plate 24;
the positive electrode 22, the negative electrode 23, and the insulating plate 24 are disposed inside the drill 13; the positive electrode 22 and the negative electrode 23 are arranged in parallel, and the positive electrode 22 and the negative electrode 23 are fixed on the insulating plate 24.
The plasma discharge system 20 further includes a positive electrode cable 25 and a negative electrode cable 26 disposed inside the auger stem 12.
The positive terminal of the plasma generator 21 is connected with the positive electrode 22 through a positive electrode cable 25; the negative end of the plasma generator 21 is connected to the negative electrode 23 through a negative electrode cable 26.
The energy emitted by the plasma generator 21 can be determined by the conductivity of the coal rock and the diameter of the drilled hole.
The plasma generator 21 is used for pre-weakening the coal rock mass, so that the strength of the coal rock mass is reduced, the abrasion of the mechanical drill bit is effectively reduced, and the service life of the drill bit is prolonged.
A positive electrode cable hole 251 for routing the positive electrode cable 25 and a negative electrode cable hole 261 for routing the negative electrode cable 26 are provided in the auger stem 12.
The directional control system 30 includes a hydraulic push rod controller 31, a hydraulic push rod 32, a rotating shaft controller 33, and an electric rotating shaft 34.
The hydraulic push rod 32 is arranged inside the auger stem 12; one end of the hydraulic pushing rod 32 is connected with the insulating plate 24, and the other end is connected with the hydraulic pushing rod controller 31.
The electric rotating shaft 34 is arranged on the hydraulic pushing rod 32; the rotating shaft controller 33 is connected to the electric rotating shaft 34.
The plasma discharge system further comprises a high voltage discharge switch 27 arranged between the positive terminal of the plasma generator 21 and the positive electrode 22.
The angle range of the electric rotating shaft 34 in the orientation control system for controlling the rotation of the electrode is-90 degrees.
As a preferred embodiment of the present invention, as shown in fig. 2, a directional drilling method for pre-weakening coal rock induced mechanical drilling includes the steps of:
s1, operating the hydraulic push rod controller 31, controlling the hydraulic push rod 32 to drill in the coal rock to a certain distance;
s2, operating the rotating shaft controller 33 to control the electric rotating shaft 34 to enable the positive electrode 22 and the negative electrode 23 to be vertical to the coal rock wall surface;
s3, starting the plasma generator 21, and closing the high-voltage discharge switch 27;
s4, the plasma discharge system 20 discharges the coal rock wall surface for multiple times to form cracks with communicated cracks, and pre-weakened coal rock is formed between the positive electrode and the negative electrode;
s5, the auger stem 12 drives the drill bit 13 to follow the drilling direction of the positive electrode 22 and the negative electrode 23, and the weakened coal rock interface is drilled continuously to realize directional drilling.
As a second preferred embodiment of the present invention, as shown in fig. 3 and 4, a directional drilling method for pre-weakening coal rock induced mechanical drilling includes the following steps:
s1, operating the hydraulic push rod controller 31, controlling the hydraulic push rod 32 to drill a certain distance in the coal rock;
s2, operating the rotating shaft controller 33 to control the electric rotating shaft 34 to enable the positive electrode 22 and the negative electrode 23 to always keep an angle of 10 degrees with the coal rock wall surface;
s3, starting the plasma generator 21, and closing the high-voltage discharge switch 27;
s4, the plasma discharge system 20 discharges for multiple times on the coal rock wall surface to form cracks with mutually communicated cracks, and pre-weakened coal rock is formed between the positive electrode and the negative electrode;
s5, the auger stem 12 drives the drill bit 13 to follow the drilling direction of the positive electrode 22 and the negative electrode 23, and the weakened coal rock interface is drilled continuously to realize directional drilling.
Although the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the details of the embodiments, and various equivalent modifications can be made within the technical spirit of the present invention, and the scope of the present invention is also within the scope of the present invention.
Claims (6)
1. The utility model provides a weaken coal petrography induced mechanical drilling's directional drilling device in advance which characterized in that: comprises a mechanical drilling system (10), a plasma discharge system (20) and a directional control system (30);
the mechanical drilling system (10) comprises a drilling machine (11), an auger stem (12) and a drill bit (13);
one end of the spiral drill rod (12) is connected with the drilling machine (11), and the other end of the spiral drill rod is connected with the drill bit (13);
the plasma discharge system (20) comprises a plasma generator (21), a positive electrode (22), a negative electrode (23) and an insulating plate (24);
the positive electrode (22), the negative electrode (23) and the insulating plate (24) are arranged inside the drill bit (13); the positive electrode (22) and the negative electrode (23) are arranged in parallel, and the positive electrode (22) and the negative electrode (23) are fixed on the insulating plate (24);
the plasma discharge system (20) further comprises a positive electrode cable (25) and a negative electrode cable (26) which are arranged inside the auger stem (12);
the positive end of the plasma generator (21) is connected with the positive electrode (22) through a positive electrode cable (25); the negative end of the plasma generator (21) is connected with the negative electrode (23) through a negative electrode cable (26);
the directional control system (30) comprises a hydraulic pushing rod controller (31), a hydraulic pushing rod (32), a rotating shaft controller (33) and an electric rotating shaft (34);
the hydraulic push rod (32) is arranged inside the auger stem (12); one end of the hydraulic pushing rod (32) is connected with the insulating plate (24), and the other end of the hydraulic pushing rod is connected with the hydraulic pushing rod controller (31);
the electric rotating shaft (34) is arranged on the hydraulic pushing rod (32); the rotating shaft controller (33) is connected with the electric rotating shaft (34).
2. The directional drilling device for pre-weakened coal rock induction mechanical drilling as claimed in claim 1, wherein: the plasma discharge system also comprises a high-voltage discharge switch (27) arranged between the positive terminal and the positive electrode (22) of the plasma generator (21).
3. The directional drilling device for pre-weakened coal rock induction mechanical drilling as claimed in claim 2, wherein: a positive electrode cable hole (251) for arranging a positive electrode cable (25) and a negative electrode cable hole (261) for arranging a negative electrode cable (26) are formed in the spiral drill rod (12).
4. The directional drilling device for pre-weakened coal rock induction mechanical drilling as claimed in claim 2, wherein: an electrode movable cavity (131) is arranged in the drill bit (13).
5. The directional drilling device for pre-weakened coal rock induction mechanical drilling as claimed in claim 2, wherein: the angle range of the electric rotating shaft (34) in the orientation control system for controlling the rotation of the electrode is-90 degrees.
6. The directional drilling method of the directional drilling device for pre-weakened coal rock induced mechanical drilling is based on any one of claims 2 to 5, and is characterized in that: the method comprises the following steps:
s1, operating a hydraulic push rod controller (31) to control a hydraulic push rod (32) to drill in the coal rock to a certain distance;
s2, operating a rotating shaft controller (33) and controlling an electric rotating shaft (34) to enable a drilling angle to be formed between a positive electrode (22) and a negative electrode (23) and the wall surface of the target coal rock, wherein the angle range is-90 degrees;
s3, starting the plasma generator (21), and closing the high-voltage discharge switch (27);
s4, the plasma discharge system (20) discharges the coal rock wall surface for multiple times to form cracks with communicated cracks, and pre-weakened coal rock is formed between the positive electrode and the negative electrode;
s5, the auger stem (12) drives the drill bit (13) to follow the drilling direction of the positive electrode (22) and the negative electrode (23), the weakened coal rock interface is drilled continuously, and directional drilling is achieved.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202110857304.XA CN113738270B (en) | 2021-07-28 | 2021-07-28 | Directional drilling device and method for pre-weakened coal rock induced mechanical drilling |
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| CN202110857304.XA CN113738270B (en) | 2021-07-28 | 2021-07-28 | Directional drilling device and method for pre-weakened coal rock induced mechanical drilling |
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| CN113738270A CN113738270A (en) | 2021-12-03 |
| CN113738270B true CN113738270B (en) | 2022-08-26 |
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Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2420358B (en) * | 2004-11-17 | 2008-09-03 | Schlumberger Holdings | System and method for drilling a borehole |
| CN101737009B (en) * | 2009-12-01 | 2012-11-14 | 中国石油集团长城钻探工程有限公司 | Liquid-gas phase drilling medium rotary table driving geosteering drilling system |
| US20130032399A1 (en) * | 2011-08-02 | 2013-02-07 | Halliburton Energy Services, Inc. | Systems and Methods for Directional Pulsed-Electric Drilling |
| CN107816317B (en) * | 2017-11-22 | 2019-02-22 | 中国矿业大学 | A kind of fast drilling device and method that high electric field pulse is mutually cooperateed with power auger |
| CN109577859B (en) * | 2018-07-03 | 2020-04-07 | 西南石油大学 | Continuous tube high-voltage electric pulse-mechanical composite rock breaking drilling method |
| CN110388206B (en) * | 2019-06-13 | 2020-11-27 | 太原理工大学 | Method and device for plasma uplink fracturing of residual coal pillar in residual mining area |
| CN112412425B (en) * | 2020-11-19 | 2021-11-09 | 中国矿业大学 | Electric pulse prefabricated crack directional hydraulic fracturing integrated method |
| CN112523695B (en) * | 2020-12-04 | 2022-09-02 | 北京建工环境修复股份有限公司 | Drilling directional mechanism and drilling and production equipment of coiled tubing |
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