CN111810164B - Hard roof cutting method based on perforation and hydraulic fracturing - Google Patents
Hard roof cutting method based on perforation and hydraulic fracturing Download PDFInfo
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- CN111810164B CN111810164B CN202010669563.5A CN202010669563A CN111810164B CN 111810164 B CN111810164 B CN 111810164B CN 202010669563 A CN202010669563 A CN 202010669563A CN 111810164 B CN111810164 B CN 111810164B
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- 238000005520 cutting process Methods 0.000 title claims abstract description 43
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000005553 drilling Methods 0.000 claims description 23
- 238000007789 sealing Methods 0.000 claims description 16
- 239000002360 explosive Substances 0.000 claims description 15
- 239000004480 active ingredient Substances 0.000 claims description 4
- 230000035945 sensitivity Effects 0.000 claims description 3
- 239000003814 drug Substances 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 238000005086 pumping Methods 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 claims 1
- 230000001154 acute effect Effects 0.000 claims 1
- 239000010959 steel Substances 0.000 claims 1
- 238000005422 blasting Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000011435 rock Substances 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
- 238000005065 mining Methods 0.000 description 3
- 239000003245 coal Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000005755 formation reaction Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
- E21D9/006—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries by making use of blasting methods
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D3/00—Particular applications of blasting techniques
- F42D3/04—Particular applications of blasting techniques for rock blasting
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
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- General Engineering & Computer Science (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
Abstract
The invention belongs to the technical field of hard roof cutting, in particular to a hard roof cutting method based on perforation and hydraulic fracturing, which solves the technical problems in the background technology.
Description
Technical Field
The invention belongs to the technical field of hard roof cutting, and particularly relates to a hard roof cutting method based on perforation and hydraulic fracturing.
Background
Coal is a main primary energy source in China, so safe and efficient mining of mines is particularly important. There are many factors that affect the normal production of coal mines, such as gas, water, fire, etc. Among these factors, the problem of strong mine pressure caused by hard roof panels is very prominent. The hard top plate can be suspended in a large area in the process of mining on the working face, and after the critical breaking step distance is reached, the hard top plate collapses in a large area, so that impact mine pressure and gas are instantly pressed out, and huge hidden dangers are brought to safe and efficient mining of a mine. Aiming at the problem of hard top plates, two means of hydraulic fracturing or energy-gathering blasting are generally adopted in China. The crack propagation of hydraulic fracturing is along the direction of the maximum principal stress, the form of the crack is difficult to control, the roof cutting effect has randomness, the disturbance of energy-gathered blasting to surrounding rocks of a roadway is large, and the maintenance of the roadway is influenced to a certain extent, so that a roof cutting method which can control the roof cutting direction and has small disturbance to the surrounding rocks is urgently needed at present.
Disclosure of Invention
The invention aims to solve the technical problems in the background art and provides a hard top plate cutting method based on perforation and hydraulic fracturing.
The technical means for solving the technical problems of the invention is as follows: a hard top plate cutting method based on perforation and hydraulic fracturing is characterized by comprising the following steps:
the method comprises the following steps: drilling on one side of the tunnel, wherein the inclined angle of the drill and the horizontal plane is theta, and the diameter of the drill is D1A first bore of depth H, wherein the first bore has a diameter D1The uniaxial compressive strength σ of the hard top plate is related to: d1≥D0σ/σ0In the formula, σ0Is the coefficient of sensitivity, σ, of the borehole to uniaxial compressive strength of the hard top plate0Is a constant, σ0＝5.0MPa， D0Is the standard borehole diameter, D0＝4.5mm；
Step two: will have a width L1Height of L2The joint cutting gun is pushed into the bottom of the first drilling hole, and meanwhile, the perforating direction of a medicine cover opening of the joint cutting gun is ensured to be parallel to the central line of the roadway;
step three: leading the detonating cord of the joint cutting gun out of the first drill hole, and then sealing the hole;
step four: exciting a detonating cord to detonate the joint-cutting explosive;
step five: drilling a hole sealing section with the diameter D2The second drilling hole keeps the axis of the second drilling hole coincident with the axis of the first drilling hole, and meanwhile, the second drilling hole penetrates through the hole sealing section;
Step six: putting the hydraulic fracturing gun into the first drilling hole through the second drilling hole, and sealing the second drilling hole;
step seven: fracturing by adopting a high-pressure pump station with pressure P, and stopping fracturing when the pressure of the high-pressure pump station is suddenly reduced;
step eight: and (5) translating the tunnel to the other end of the tunnel, repeating the first step to the seventh step, and cutting the next wheel top plate.
Preferably, the lancing gun is of a long strip structure with an X-shaped longitudinal section, the left side and the right side of the lancing gun are both provided with acute-angle explosive cover openings which are sunken inwards, explosive is filled in the lancing gun, and a detonating cord is led out of the explosive. The construction of the lancing gun can also be other constructions known in the art.
Preferably, the angle θ of inclination of the first bore to the horizontal is in the range of 65 ° to 75 °. Within this angle range, the fracturing effect is good, and within this range, the hard roof disturbance can be reduced as much as possible.
Preferably, the first drilling depth H ensures that the first drilling end is at a vertical distance of 0.5m to 0.8m from the top of the hard roof. This is to ensure that the fracture penetrates the hard roof as far as possible without any further fluid leakage between the formations.
Preferably, the width L of the lance gun1Is a first bore diameter D 10.85 to 0.95 times of the total weight of the composition. This is to ensure that the lance can produce as deep a crack as possible and also to facilitate the installation of the lance.
Preferably, the lance height L2Is the width L of the cutting lance10.4 to 0.5 times of the amount of the active ingredient. The joint cutting gun is used for ensuring that the size of a crack formed by blasting can meet the requirement of follow-up fracturing, meanwhile, the damage to surrounding rocks is reduced, the crack expansion is prevented from being difficult to control, and the liquid leakage phenomenon is avoided.
Preferably, the diameter D of the second bore hole2Is the first bore diameter D10.3 to 0.4 times of the amount of the active ingredient. The second borehole is thinner than the first borehole because the second borehole is drilled in the sealing section of the first borehole, and D for subsequent continued sealing2Is D1Preferably 0.3 to 0.4 times of the total amount of the above-mentioned components.
Preferably, the pressure P of the high-pressure pumping station is related to the coefficient of prestige f of the hard roof: when 0 is present<f<4, P is greater than or equal to 40MPa but less than 60 MPa; when f is more than or equal to 4<When 8, P is more than or equal to 60 MPa; when f is more than or equal to 8, P is 60+ (f-8) P0Above, P0Is a standard pressure, P05.6 MPa. The cost is too high and waste exists due to the fact that the pressure of the high-pressure pump station is too high; the pressure of the pump station is small, the hard roof cannot be pressed, so the pressure P of the high-pressure pump station is set according to the correlation between the pressure P of the high-pressure pump station and the coefficient f of the hard roof, and the fracturing effect is good.
Preferably, in the sixth step, the second drill hole is sealed by rubber, and the sealing effect of the rubber is good, so that side leakage of water flow is not easy to cause.
Preferably, the translation distance S in the step eight is 2.5-3 m, which is to ensure that the adjacent drill space cracks penetrate through.
In the method of the invention, the first drilling diameter D of the first step1This, in relation to the uniaxial compressive strength σ of the hard top plate, ensures that subsequent lancing guns can produce cracks of a certain depth.
The invention has the beneficial effects that: the method is easy to operate and low in cost; the problems that the form of a crack is difficult to control when hydraulic fracturing is only adopted and disturbance on surrounding rocks of a roadway is large when energy-gathered blasting is only adopted are solved; the method comprises the steps of firstly adopting a lancing gun to orient lancing to provide a foundation for controlling the cutting direction of the hard top plate, secondly adopting a fracturing gun to perform hydraulic fracturing to increase crack expansion and reduce disturbance of the hard top plate, and mutually matching the orienting lancing and the hydraulic fracturing in time and space to finish oriented weak disturbance cutting of the hard top plate.
Drawings
Fig. 1 is a cutting arrangement diagram of a temporary roadway lancing gun in the implementation of the hard roof cutting method based on perforation and hydraulic fracturing.
FIG. 2 is a cross-sectional view taken along line I-I of FIG. 1.
Fig. 3 is a schematic view of the construction of the lance.
Fig. 4 is a fracture diagram of an adjacent empty roadway when the hard roof cutting method based on perforation and hydraulic fracturing is implemented.
In the figure: 1-near-empty roadway, 2-first drilling, 3-joint cutting gun, 4-explosive cover opening, 5-roadway central line, 6-detonating cord, 7-explosive, 8-hole sealing section, 9-second drilling, 10-hydraulic fracturing gun, 11-rubber and 12-high-pressure pump station.
Detailed Description
A hard roof cutting method based on perforation and hydraulic fracturing according to the present invention will be described in detail with reference to fig. 1, 2, 3 and 4.
Example (b): a hard top plate with the thickness of 8m is arranged 20m above an adjacent empty roadway 1 of a certain mine. The uniaxial compressive strength sigma of the hard top plate is 90MPa, and the coefficient f of the Pouleian coefficient is 9; the method for cutting the hard top plate based on perforation and hydraulic fracturing comprises the following specific steps:
the method comprises the following steps: drilling a side of the blank roadway 1, wherein the inclination angle theta of the drill to the horizontal plane is 65 DEG, and the diameter D of the drill is D1A first bore 2 of 81mm and a depth H of 31.5m, wherein the first bore 2 has a diameter D1The uniaxial compressive strength σ of the hard top plate is related to: d 1≥D0σ/σ0In the formula, σ0Is the coefficient of sensitivity, σ, of the borehole to uniaxial compressive strength of the hard top plate0Is a constant, σ0＝5.0MPa，D0Is the standard borehole diameter, D04.5 mm; the depth H of the first drill hole 2 meets the requirement that the vertical distance between the tail end of the first drill hole 2 and the top of the hard top plate is 0.5-0.8 m; as shown in particular in fig. 1;
step two: will have a width L1Is 72.9mm and has a height L2A 29.2mm cutting gun 3 is pushed into the bottom of the first drilling hole 2, and meanwhile, the perforating direction of the explosive cover opening 4 is ensured to be parallel to the central line of the temporary roadway 1; width L1Diameter D of the first bore 210.9 times of (C), height L2Is a width L10.4 times higher as shown in fig. 2; the lancing gun 3 is of a long-strip-shaped structure with an X-shaped longitudinal section, the left side and the right side of the lancing gun 3 are both provided with acute-angle explosive cover openings (4) which are sunken inwards, the inside of the lancing gun 3 is filled with explosive 7, an explosion fuse 6 is led out from the explosive 7, and the structure of the lancing gun 3 is shown in figure 3;
step three: leading the detonating cord 6 of the joint cutting gun 3 out of the first drilling hole 2, and then sealing the hole;
step four: the detonating cord 6 is excited to detonate the joint-cutting explosive 7;
step five: drilling a diameter D on the hole sealing section 82A second bore 9 of 24mm, the second bore 9 being maintained coincident with the axis of the first bore 2, while the second bore 9 penetrates the hole sealing section 8; diameter D of second bore 9 2About 0.3 times the diameter of the first bore 2; as shown in fig. 4;
step six: placing a hydraulic fracturing gun 10 into the first borehole 2 through the second borehole 9, and sealing the second borehole 9; as shown in fig. 4;
step seven: fracturing by adopting a high-pressure pump station 12 with the pressure P of 65.6MPa, and stopping fracturing when the pressure of the high-pressure pump station 12 is suddenly reduced; because the coefficient of prev f is 9, the correlation between the pressure P of the high-pressure pump station 12 and the coefficient of prev f of the hard roof can be obtained as follows: when f is more than or equal to 8, P is 60+ (f-8) P0Above, P0Is a standard pressure, P05.6MPa, i.e., P60 + (9-8) × 5.6 ═ 65.6 MPa;
step eight: and (5) translating the other end of the adjacent empty roadway 1 for 3m, repeating the steps from the first step to the seventh step, and cutting the top plate of the next wheel.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. A hard top plate cutting method based on perforation and hydraulic fracturing is characterized by comprising the following steps:
The method comprises the following steps: drilling a side of the blank roadway (1) to form an inclined angle theta with the horizontal plane and a diameter D1A first bore (2) of depth H, wherein the first bore (2) has a diameter D1The uniaxial compressive strength σ of the hard top plate is related to: d1≥D0σ/σ0In the formula, σ0Is the coefficient of sensitivity, σ, of the borehole to uniaxial compressive strength of the hard top plate0Is a constant, σ0＝5.0MPa，D0Is the standard borehole diameter, D0＝4.5mm；
Step two: will have a width L1A height of L2The lancing gun (3) is pushed into the bottom of the first drilling hole (2), and meanwhile, the perforating direction of a medicine cover opening (4) of the lancing gun (3) is ensured to be parallel to the central line of the adjacent empty roadway (1);
step three: leading the detonating cord (6) of the joint cutting gun (3) out of the first drilling hole (2), and then sealing the hole;
step four: the detonating fuse (6) is excited to detonate the explosive (7) of the kerf gun (3);
step five: drilling a hole sealing section (8) with the diameter D2Keeping the second bore (9) coincident with the axis of the first bore (2) while the second bore (9) penetrates the hole sealing section (8);
step six: placing the hydraulic fracturing gun (10) into the first borehole (2) through the second borehole (9), and sealing the second borehole (9);
step seven: fracturing by adopting a high-pressure pump station (12) with pressure P, and stopping fracturing when the pressure of the high-pressure pump station (12) is suddenly reduced;
Step eight: and (5) translating the steel plate to the other end of the adjacent empty roadway (1), repeating the steps from the first step to the seventh step, and cutting the top plate of the next wheel.
2. A hard roof cutting method based on perforation and hydraulic fracturing, according to the claim 1, characterized in that the slit gun (3) is a long strip structure with the longitudinal section of "X", the left side and the right side of the slit gun (3) are provided with acute angle explosive cover openings (4) which are concave inwards, the inside of the slit gun (3) is filled with explosive (7), and the explosive (7) leads out a detonating cord (6).
3. A method of cutting a hard top plate based on perforation and hydraulic fracturing as claimed in claim 1, characterized in that the first perforations (2) are inclined by an angle θ of 65 ° to 75 ° to the horizontal plane.
4. A method for cutting a hard roof based on perforation and hydraulic fracturing, according to claim 1, characterized in that the depth H of the first borehole (2) ensures that the end of the first borehole (2) is at a vertical distance of 0.5m to 0.8m from the top of the hard roof.
5. A method of hard roof cutting based on perforation and hydraulic fracturing as per claim 1, characterized by the width L of the lance (3)1Is the diameter D of the first bore hole (2)10.85 to 0.95 times of the total weight of the composition.
6. A method of hard roof cutting based on perforation and hydraulic fracturing as per claim 1, characterized by that, the height L of the lance (3) 2Is the width L of the cutting lance (3)10.4 to 0.5 times of the amount of the active ingredient.
7. A method for cutting a hard roof based on perforation and hydraulic fracturing, according to claim 1, characterized in that the diameter D of the second borehole (9)2Is the diameter D of the first bore hole (2)10.3 to 0.4 times of the amount of the active ingredient.
8. A method of hard roof cutting based on perforation and hydraulic fracturing according to any of the claims 1-7, characterized in that the pressure P of the high pressure pumping station (12) is related to the Pyth coefficient f of the hard roof: when 0 is present<f<4, P is greater than or equal to 40MPa but less than 60 MPa; when f is more than or equal to 4<When 8, P is more than or equal to 60 MPa; when f is more than or equal to 8, P is 60+ (f-8) P0Above, P0Is a standard pressure, P0＝5.6MPa。
9. A hard roof cutting method based on perforation and hydraulic fracturing, according to claim 8, characterized in that in step six the second borehole (9) is sealed with rubber (11).
10. A hard roof cutting method based on perforation and hydraulic fracturing is characterized in that the translation distance S in the step eight is 2.5-3 m.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010669563.5A CN111810164B (en) | 2020-07-13 | 2020-07-13 | Hard roof cutting method based on perforation and hydraulic fracturing |
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| CN202010669563.5A CN111810164B (en) | 2020-07-13 | 2020-07-13 | Hard roof cutting method based on perforation and hydraulic fracturing |
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| CN111810164B true CN111810164B (en) | 2022-05-31 |
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| CN112696185A (en) * | 2021-01-28 | 2021-04-23 | 太原理工大学 | Composite blasting high-energy gas directional accurate fracturing method |
| CN114033375A (en) * | 2021-11-26 | 2022-02-11 | 重庆大学 | Hydraulic grooving and high-pressure splitting coupled hard top plate seam forming method |
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| CN103527198A (en) * | 2013-10-21 | 2014-01-22 | 中国矿业大学 | Hydraulic fracturing control method of cut tight roof/top coal |
| CN107091600A (en) * | 2017-04-07 | 2017-08-25 | 安徽理工大学 | A kind of linear orientation jet cutter |
| CN207377560U (en) * | 2017-09-06 | 2018-05-18 | 河南省生产力促进中心 | A kind of orientation hydraulic fracturing overhead caving device |
| CN108843320A (en) * | 2018-06-12 | 2018-11-20 | 王帆 | Shift to an earlier date outburst elimination method in the tunnel of coal mine tight roof full face |
| CN109339855A (en) * | 2018-11-27 | 2019-02-15 | 中煤科工集团西安研究院有限公司 | Continuous pipe perforation staged fracturing method in coal mine gas extraction jumping chisel hole sleeve |
| CN109958421A (en) * | 2019-03-19 | 2019-07-02 | 中国矿业大学(北京) | Top relief construction method and drilling machine are cut in a kind of precracking hydraulic fracturing |
| CN110259447A (en) * | 2019-06-07 | 2019-09-20 | 太原理工大学 | Underground coal mine oriented perforating pressure break cuts top release shield lane method |
| CN110410053A (en) * | 2019-08-29 | 2019-11-05 | 重庆科技学院 | Coal mine roof plate pressure relief method based on eyelet supporting |
-
2020
- 2020-07-13 CN CN202010669563.5A patent/CN111810164B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103527198A (en) * | 2013-10-21 | 2014-01-22 | 中国矿业大学 | Hydraulic fracturing control method of cut tight roof/top coal |
| CN107091600A (en) * | 2017-04-07 | 2017-08-25 | 安徽理工大学 | A kind of linear orientation jet cutter |
| CN207377560U (en) * | 2017-09-06 | 2018-05-18 | 河南省生产力促进中心 | A kind of orientation hydraulic fracturing overhead caving device |
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