CN113266367B - Automatic roof cutting method for hydraulic rod of hard roof roadway - Google Patents
Automatic roof cutting method for hydraulic rod of hard roof roadway Download PDFInfo
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- CN113266367B CN113266367B CN202110605807.8A CN202110605807A CN113266367B CN 113266367 B CN113266367 B CN 113266367B CN 202110605807 A CN202110605807 A CN 202110605807A CN 113266367 B CN113266367 B CN 113266367B
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- 238000005520 cutting process Methods 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 14
- 239000007788 liquid Substances 0.000 claims abstract description 47
- 238000005065 mining Methods 0.000 claims abstract description 29
- 239000003245 coal Substances 0.000 claims abstract description 28
- 239000000839 emulsion Substances 0.000 claims abstract description 20
- 230000000694 effects Effects 0.000 claims abstract description 9
- 238000005553 drilling Methods 0.000 claims abstract description 7
- 238000004364 calculation method Methods 0.000 claims abstract description 6
- 239000010720 hydraulic oil Substances 0.000 claims abstract description 6
- 230000001276 controlling effect Effects 0.000 claims abstract description 4
- 238000003825 pressing Methods 0.000 claims abstract description 4
- 230000001105 regulatory effect Effects 0.000 claims abstract description 4
- 238000004088 simulation Methods 0.000 claims abstract description 3
- 239000011435 rock Substances 0.000 claims description 21
- 238000005086 pumping Methods 0.000 claims description 6
- 238000009434 installation Methods 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 description 4
- 238000005422 blasting Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 230000002045 lasting effect Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
Classifications
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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
- E21D9/001—Improving soil or rock, e.g. by freezing; Injections
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Soil Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
Abstract
The invention belongs to the field of mining engineering, and particularly relates to an automatic roof cutting method for a hydraulic rod of a roadway with a hard roof. S1-constructing a theoretical calculation model of the hard roof of the roadway, determining the arrangement distance and the hole depth of the fracturing holes of the hard roof by combining numerical simulation calculation results, and making a roof cutting operation rule. S2, installing a coal pillar stress monitor. S3, installing a liquid supply system: and installing a mining hydraulic oil pump on the roadway floor. S4, drilling a fracturing hole and installing a hydraulic rod. S5, detecting the tightness of the pipeline of the hydraulic system. S6, pressing the hydraulic rod by adopting a mining emulsion pump. S7, regulating and controlling the pressure of the hydraulic rod. S8, circularly operating the steps until the top of all branches of the roadway is cut. The method can realize the universality of roof cutting operation of the hard roof roadway of the coal seam with all occurrence characteristics; realize the manual control of cutting the top effect, avoid causing blind cutting the top.
Description
Technical Field
The invention belongs to the field of mining engineering, and particularly relates to an automatic roof cutting method for a hydraulic rod of a roadway with a hard roof.
Background
In underground coal mining, the stability of surrounding rock of a stoping roadway is severely affected by mining activities of a working face. The hard roof roadway is a roadway which is characterized in that the roof is a layer of stratum with strong hardness, large thickness and crack development degree. When the tunnel roof is a hard roof, the stress of surrounding rock of the tunnel is more easily concentrated, and rock burst accidents are easily caused, so that casualties and economic losses are caused. Meanwhile, if the hard roof roadway is combined with the gob-side entry driving or the gob-side entry retaining coal mining method, roof cutting operation is carried out on the hard roof so as to avoid stress concentration in the hard roof of the roadway and rock burst accidents. The main methods of roof cutting of the existing hard roof roadway in China are technologies such as blasting roof cutting, hydraulic fracturing and the like, the blasting roof cutting technology has high requirements on occurrence conditions of mine coal beds, the mine coal beds cannot be popularized in all mines, the hydraulic fracturing technology has strict requirements on technical equipment and roof lithology, and the defects severely limit the roof cutting operation effect of the hard roof roadway.
Disclosure of Invention
Based on the defects of the rock burst prevention measures, the invention provides an automatic roof cutting method for a hydraulic rod of a hard roof roadway. The hydraulic rod is used for pressurizing to carry out in-situ fracturing on the hard roof, so that cracks in surrounding rock of the roof are developed, the strength of the roof is reduced, and roof cutting operation of a roadway is realized.
The invention adopts the following technical scheme: an automatic roof cutting method for a hydraulic rod of a hard roof roadway comprises the following steps.
S1, constructing a theoretical calculation model of the hard roof of the roadway, determining the arrangement interval and the hole depth of the fracturing holes of the hard roof by combining numerical simulation calculation results, and making a roof cutting operation rule.
S2, installing a coal pillar stress monitor: and (3) taking 1.5m as a distance, installing a coal pillar stress monitor in the coal pillar of the roadway, and monitoring the internal stress of the coal pillar.
S3, installing a liquid supply system: and installing a mining hydraulic oil pump on the roadway floor.
S4-fracturing hole drilling and hydraulic rod installation: and drilling a fracturing hole in a side roof of the goaf of the hard roof roadway, and placing the cast hydraulic rod into the fracturing hole.
S5, connecting a liquid inlet of the hydraulic rod with a liquid outlet of the mining emulsion pump by adopting a liquid inlet pipeline, connecting the liquid outlet of the hydraulic rod with the liquid inlet of the mining emulsion pump by using a liquid return pipeline, installing a pressure relief valve on a pressure relief pipeline of the hydraulic rod, and detecting the tightness of a pipeline of a hydraulic system.
S6, pressing the hydraulic rod by adopting a mining emulsion pump until the pressure reaches 80MPa, prefabricating cracks are carried out on a hard roof of a roadway, if the roof of surrounding rock of the roadway is extremely hard, namely the single-pumping compressive strength of a roof stratum is more than 100 MPa, increasing the initial hydraulic pressure supply until the initial hydraulic pressure is equal to the single-pumping compressive strength of the roof stratum, increasing the fracturing time, and circularly loading and unloading the hydraulic rod at intervals of 5h.
S7, regulating and controlling the pressure of the hydraulic rod.
S8, circularly operating the steps until the top of all branches of the roadway is cut.
In the step S1, taking a roof rock sample from an underground roadway, and measuring uniaxial compressive strength P of a hard rock layer of the roadway roof in a laboratory, wherein if P is more than 60MPa, the arrangement interval of fracturing holes of the hard roof is determined to be 0.5m, and the hole depth is determined to be three fourths of the thickness of the hard rock layer; if P is less than or equal to 60MPa, determining that the arrangement interval of the fracturing holes of the hard top plate is 1.0m, and the depth of the holes is half of the thickness of the hard rock layer.
In step S7, observing the indication of the coal pillar stress monitor, if the indication of the monitor is stable, the hard roof stratum is not destroyed, a roof cutting effect is not formed, at the moment, the liquid supply pressure of the mining emulsion pump is increased, the internal pressure of the hydraulic rod is increased to 100MPa, and the pressure is continuously applied until the indication of the monitor is suddenly reduced; if the display number of the monitor is rapidly reduced and tends to 0MPa, the hard top plate is successfully pre-cracked, and the roadway roof cutting operation is completed; if the monitor gauge is reduced but does not trend toward 0MPa, indicating that the hard top plate is breaking, the hydraulic rod internal 80 MPa pressure should be maintained until the monitor gauge data trend toward 0 MPa.
The hydraulic rod may be replaced with a hydraulic mount.
Compared with the prior art, after the hydraulic rod is placed in the fracturing hole in the hard roof, the hydraulic rod can be pressurized through the mining emulsion pump, so that the inner wall of the fracturing hole is subjected to larger pressure, cracks are generated in the hard roof and further develop, and a roof cutting effect is formed; realizing manual control of the roof cutting effect, and avoiding blind roof cutting; the automation of the bisection roof operation flow is realized, and the heavy work of a line of workers is avoided; the safety operation in the process of roof cutting operation is ensured to a great extent; meanwhile, the technology can be widely applied to roof-hanging roof-falling of an end face roof, roof-cutting of a gob-side entry retaining roof and roof-cutting of a roof coal prefabricating crack in fully mechanized mining.
Drawings
FIG. 1 is a schematic diagram of an embodiment of the present invention;
FIG. 2 is a general assembly view of the present invention;
FIG. 3 is a front view of a hydraulic stick;
FIG. 4 is a left side view of the hydraulic stick;
FIG. 5 is a bottom view of a hydraulic stick;
In the figure, a roadway bottom plate, a 2-coal bed, a 3-roadway top plate, a 4-roadway, a 5-anchor rod, a 6-hydraulic rod, a 7-mining hydraulic oil pump, an 8-hydraulic rod pressure relief valve, a 9-hydraulic rod liquid inlet, a 10-liquid inlet pipeline, a 11-mining hydraulic oil pump liquid outlet, a 12-hydraulic rod liquid outlet, a 13-liquid return pipeline, a 14-mining emulsion pump liquid inlet, a 15-goaf, a 16-coal pillar and a 17-coal pillar stress monitor are shown.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Referring to fig. 1, in order to achieve the above object, the present invention provides an automatic roof cutting device for hydraulic rods of a hard roof roadway. The hydraulic rod fracturing system comprises a hydraulic rod liquid supply system and a hydraulic rod fracturing system; the hydraulic rod liquid supply system comprises a mining emulsion pump 7, a liquid inlet pipeline 10 and a liquid return pipeline 13, and the hydraulic rod fracturing system comprises a hydraulic rod 6 and a hydraulic rod pressure relief valve 8. The hydraulic rod 6 is arranged in a fracturing hole drilled on the hard top plate 3, a hydraulic rod liquid inlet 9, a hydraulic rod pressure relief valve 8 and a hydraulic rod liquid return port 12 are arranged on the outer side of the hydraulic rod, the mine emulsion pump 7 is arranged on the roadway bottom plate 1, the hydraulic rod liquid inlet 9 is connected with a mine emulsion pump liquid outlet 14 through a liquid inlet pipeline 10, the hydraulic rod liquid return port 12 is connected with a mine emulsion pump liquid return port 11 through a liquid return pipeline 13, and a coal pillar stress monitor 17 is arranged inside a roadway coal pillar 16.
Further, the spacing of the fracture holes drilled in the hard roof is determined by the uniaxial compressive strength of the hard roof formation.
Further, the hydraulic rod is integrally cast by stainless steel with the thickness of 5mm, the ultimate strength is 120MPa, the diameter is 5cm, the length is 3m, meanwhile, a liquid inlet 9, a liquid return port 12 and a pressure relief pipe are cast on the outer side of the hydraulic rod, the pressure relief valve 8 is arranged on the pressure relief pipe, and the pressure relief pipe is connected to the mining emulsion pump 7 through a liquid inlet pipeline 10 and a liquid return pipeline 13. The hydraulic rod can also be replaced by a hydraulic bracket.
In order to achieve the purpose, the invention provides an automatic roof cutting device for a hydraulic rod of a roadway with a hard roof and a using method thereof, comprising the following steps:
S1-taking a roof rock sample from an underground roadway, measuring uniaxial compressive strength P of a hard rock layer of the roadway roof in a laboratory, and if P is more than 60MPa, determining that the arrangement interval of fracturing holes of the hard roof is 0.5m and the depth of the holes is three fourths of the thickness of the hard rock layer; if P is less than 60MPa, the arrangement interval of the fracturing holes of the hard top plate is determined to be 1.0m, and the depth of the holes is half of the thickness of the hard rock stratum.
S2, installing a coal pillar stress monitor: and (3) taking 1.5m as a distance, installing a coal pillar stress monitor in the coal pillar of the roadway, and monitoring the internal stress of the coal pillar.
S3, installing a liquid supply system: and installing a mining hydraulic oil pump on the roadway floor.
S4-fracturing hole drilling and hydraulic rod installation: drilling a fracturing hole in a side roof of a goaf of a hard roof roadway, and placing a cast hydraulic rod into the fracturing hole;
S5, connecting a hydraulic rod liquid inlet 9 with a mining emulsion pump liquid outlet 11 by adopting a liquid inlet pipeline 10, connecting a hydraulic rod liquid outlet 12 with a mining emulsion pump liquid inlet 14 by using a liquid return pipeline 13, installing a pressure relief valve on a hydraulic rod pressure relief pipeline, and detecting the tightness of a hydraulic system pipeline;
s6, pressing the hydraulic rod by adopting a mining emulsion pump until the pressure reaches 80MPa, and lasting the pressure time of 80MPa for 2 hours, so as to realize the effect of prefabricating cracks on the hard top plate of the roadway; if the roadway surrounding rock roof is extremely hard, namely the roof strata single-pumping compressive strength is greater than 100 MPa, increasing the initial supply pressure to be equal to the roof strata single-pumping compressive strength, increasing the fracturing time, and circularly loading and unloading the hydraulic rod at intervals of 5h until the indication number of the coal pillar stress monitor tends to 0MPa.
S7, regulating and controlling the pressure of the hydraulic rod: observing the indication of the coal pillar stress monitor, if the indication of the monitor is stable, indicating that the hard roof stratum is not destroyed and a roof cutting effect is not formed, increasing the liquid supply pressure of the mining emulsion pump, increasing the internal pressure of the hydraulic rod to 100MPa, and continuously applying the pressure until the indication of the monitor is suddenly reduced; if the display number of the monitor is rapidly reduced and tends to 0MPa, the hard top plate is successfully pre-cracked, and the roadway roof cutting operation is completed; if the monitor gauge is reduced but does not trend toward 0MPa, indicating that the hard top plate is breaking, the hydraulic rod internal 80 MPa pressure should be maintained until the monitor gauge data trend toward 0 MPa.
S8, circularly operating the steps until the top of all branches of the roadway is cut.
Claims (3)
1. An automatic roof cutting method for a hydraulic rod of a hard roof roadway is characterized by comprising the following steps of: comprises the steps of,
S1, constructing a theoretical calculation model of the hard roof of the roadway, determining the arrangement interval and the hole depth of the fracturing holes of the hard roof by combining the numerical simulation calculation result, and making a roof cutting operation rule;
s2, installing a coal pillar stress monitor: a coal pillar stress monitor is installed in a roadway coal pillar at a distance of 1.5m to monitor the internal stress of the coal pillar;
s3, installing a liquid supply system: a mining hydraulic oil pump (7) is arranged on a roadway bottom plate (1);
s4-fracturing hole drilling and hydraulic rod (6) installation: drilling a fracturing hole in a side roof of a goaf of a hard roof roadway, and placing a cast hydraulic rod (6) into the fracturing hole;
S5-connecting a liquid inlet (9) of a hydraulic rod with a liquid inlet (11) of the mining emulsion pump by adopting a liquid inlet pipeline (10), connecting a liquid outlet (12) of the hydraulic rod with a liquid inlet (14) of the mining emulsion pump by using a liquid return pipeline (13), installing a pressure relief valve on a pressure relief pipeline of the hydraulic rod, and detecting the tightness of a pipeline of a hydraulic system;
S6, pressing the hydraulic rod by adopting a mining emulsion pump until the pressure reaches 80MPa, prefabricating cracks on a hard roof of a roadway, if the roof of surrounding rock of the roadway is extremely hard, namely the single-pumping compressive strength of a roof stratum is more than 100 MPa, increasing the initial hydraulic pressure until the initial hydraulic pressure is equal to the single-pumping compressive strength of the roof stratum, increasing the fracturing time, and circularly loading and unloading the hydraulic rod at intervals of 5 h;
s7, regulating and controlling the pressure of the hydraulic rod;
In step S7, observing the indication of the coal pillar stress monitor, if the indication of the monitor is stable, the hard roof stratum is not destroyed, a roof cutting effect is not formed, at the moment, the liquid supply pressure of the mining emulsion pump is increased, the internal pressure of the hydraulic rod is increased to 100MPa, and the pressure is continuously applied until the indication of the monitor is suddenly reduced; if the display number of the monitor is rapidly reduced and tends to 0MPa, the hard top plate is successfully pre-cracked, and the roadway roof cutting operation is completed; if the monitor gauge is reduced but does not trend toward 0MPa, indicating that the hard top plate is breaking, the hydraulic rod internal 80 MPa pressure should be maintained until the monitor gauge data trend toward 0 MPa;
s8, circularly operating the steps until the top of all branches of the roadway is cut.
2. The automated roof cutting method for a hydraulic rod of a hard roof roadway of claim 1, wherein: in the step S1, taking a roof rock sample from an underground roadway, and measuring the uniaxial compressive strength P of a hard rock layer of the roadway roof in a laboratory, wherein if P is more than 60MPa, the arrangement interval of fracturing holes of the hard roof is determined to be 0.5m, and the depth of the holes is determined to be three fourths of the thickness of the hard rock layer; if P is less than or equal to 60MPa, determining that the arrangement interval of the fracturing holes of the hard top plate is 1.0m, and the depth of the holes is half of the thickness of the hard rock layer.
3. The automated roof cutting method for a hydraulic rod of a hard roof roadway of claim 1, wherein: the hydraulic rod is replaced by a hydraulic support.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110605807.8A CN113266367B (en) | 2021-05-31 | 2021-05-31 | Automatic roof cutting method for hydraulic rod of hard roof roadway |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110605807.8A CN113266367B (en) | 2021-05-31 | 2021-05-31 | Automatic roof cutting method for hydraulic rod of hard roof roadway |
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| Publication Number | Publication Date |
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| CN113266367A CN113266367A (en) | 2021-08-17 |
| CN113266367B true CN113266367B (en) | 2024-05-14 |
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| CN202110605807.8A Active CN113266367B (en) | 2021-05-31 | 2021-05-31 | Automatic roof cutting method for hydraulic rod of hard roof roadway |
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Citations (6)
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|---|---|---|---|---|
| JPS56124707A (en) * | 1980-02-01 | 1981-09-30 | Gewerk Eisenhuette Westfalia | Liquid feeder |
| JPH03271495A (en) * | 1990-03-22 | 1991-12-03 | Toda Constr Co Ltd | Monitor device in muddy water type shield chamber |
| CN102720518A (en) * | 2012-06-18 | 2012-10-10 | 太原理工大学 | Double-U ventilation system for fully-mechanized caving coal working face |
| CN108691545A (en) * | 2018-03-30 | 2018-10-23 | 张卫东 | A kind of continuous tunneling construction method of bolting with wire mesh adapting to Complex Roof shape |
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Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105545307A (en) * | 2015-12-11 | 2016-05-04 | 大同煤矿集团有限责任公司 | Method for over-pit and under-pit cooperative control of roofs of far and near fields of extra-large stoping space |
| CN107083961B (en) * | 2017-05-10 | 2019-04-26 | 中国矿业大学 | Laneway stress transfer method is pressed by force based on pressure break circle |
-
2021
- 2021-05-31 CN CN202110605807.8A patent/CN113266367B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56124707A (en) * | 1980-02-01 | 1981-09-30 | Gewerk Eisenhuette Westfalia | Liquid feeder |
| JPH03271495A (en) * | 1990-03-22 | 1991-12-03 | Toda Constr Co Ltd | Monitor device in muddy water type shield chamber |
| CN102720518A (en) * | 2012-06-18 | 2012-10-10 | 太原理工大学 | Double-U ventilation system for fully-mechanized caving coal working face |
| CN108691545A (en) * | 2018-03-30 | 2018-10-23 | 张卫东 | A kind of continuous tunneling construction method of bolting with wire mesh adapting to Complex Roof shape |
| CN108894784A (en) * | 2018-07-20 | 2018-11-27 | 中铁十九局集团矿业投资有限公司 | A kind of tight roof orientation acid fracturing control top pressure relief method |
| CN110529142A (en) * | 2019-07-30 | 2019-12-03 | 太原理工大学 | Deep tunnel pucking control device and method based on intelligent hydraulic bag |
Non-Patent Citations (1)
| Title |
|---|
| 多倾角加长工作面液压支架适用性研究;王仲伦等;《煤炭技术》;20171231;第36卷(第12期);第249-251页 * |
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| CN113266367A (en) | 2021-08-17 |
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