CN114198101A - Mobile water jet cutting continuous top cutting method for mine - Google Patents
Mobile water jet cutting continuous top cutting method for mine Download PDFInfo
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- CN114198101A CN114198101A CN202111384589.6A CN202111384589A CN114198101A CN 114198101 A CN114198101 A CN 114198101A CN 202111384589 A CN202111384589 A CN 202111384589A CN 114198101 A CN114198101 A CN 114198101A
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- 238000005520 cutting process Methods 0.000 title claims abstract description 119
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 76
- 238000000034 method Methods 0.000 title claims abstract description 49
- 239000011435 rock Substances 0.000 claims abstract description 32
- 238000005553 drilling Methods 0.000 claims abstract description 28
- 239000003245 coal Substances 0.000 claims abstract description 18
- 230000000694 effects Effects 0.000 claims abstract description 15
- 238000005065 mining Methods 0.000 claims abstract description 9
- 208000008918 voyeurism Diseases 0.000 claims abstract description 7
- 230000005641 tunneling Effects 0.000 claims description 18
- 238000010276 construction Methods 0.000 claims description 8
- 239000004576 sand Substances 0.000 claims description 7
- 125000004122 cyclic group Chemical group 0.000 claims description 4
- 238000009412 basement excavation Methods 0.000 claims description 3
- 239000000126 substance Substances 0.000 abstract description 6
- 239000000463 material Substances 0.000 abstract description 3
- 238000011084 recovery Methods 0.000 abstract 1
- 238000005516 engineering process Methods 0.000 description 6
- 206010017076 Fracture Diseases 0.000 description 4
- 238000005422 blasting Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000005755 formation reaction Methods 0.000 description 2
- 244000144985 peep Species 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 230000003631 expected effect Effects 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C41/00—Methods of underground or surface mining; Layouts therefor
- E21C41/16—Methods of underground mining; Layouts therefor
- E21C41/18—Methods of underground mining; Layouts therefor for brown or hard coal
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- Mining & Mineral Resources (AREA)
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- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
Abstract
The invention provides a mobile water jet cutting continuous roof cutting method for a mine, and belongs to the technical field of coal mining. The method comprises the steps of firstly analyzing mechanical properties of a top plate through drilling coring, determining water jet parameters, then cutting the top plate in a roadway of a working face along a drilling connection line, simultaneously observing cutting depth and effect by using a deep hole peeping instrument, dynamically adjusting the parameters, finally supporting the top plate after the top cutting is finished, recovering the working face, and processing a recovery roadway of the next working face. The invention can continuously and completely cut the roof, has controllable direction and does not change the physical and chemical properties of the coal rock mass; the material is safe in nature, does not generate harmful substances, and does not induce derived disasters; the method is safe and environment-friendly, high in top cutting speed and high in efficiency, can adapt to top cutting work under various complex conditions, can well solve disasters caused by inherent properties of thick and hard top plates, and has certain safety and economic benefits.
Description
Technical Field
The invention relates to the technical field of coal mining, in particular to a mobile water jet cutting continuous top cutting method for a mine.
Background
Along with the continuous increase of the mining depth and strength of mines in China, disasters caused by inherent properties of hard roofs, such as impact roof fall, large-range roof collapse and the like, are frequently generated under coal mines, and the nature of the disasters is that the thick hard roof is not easy to damage, destroy and collapse, so that the disasters have strong energy storage characteristics. When the suspended area of the top plate reaches the limit, the elastic energy stored in the rock stratum is easily released suddenly, so that the disaster of the top plate is caused; or the released energy acts on the surrounding coal rock mass to cause derivative disasters. Therefore, special pre-splitting or top breaking techniques are required for mining faces with thick hard formations above, especially low-lying thick hard formations.
At present, deep hole blasting, directional hydraulic fracturing, drilling and topping and other technologies achieve great results in rock stratum collapse control. However, these top plate treatments have certain limitations: under the influence of primary fractures, bedding, structure and the like, hydraulic fracturing fractures tend to turn in a short distance and are difficult to crack in a preset direction, or no fracturing process is caused by water leakage of the primary fractures of the coal rock body, so that the application range of the hydraulic fracturing fractures is limited; the safety management difficulty of the blasting pre-splitting technology is high, other disasters may be induced by harmful gas, sparks or vibration generated in the blasting process, and certain influence is exerted on the production environment and safety of mines; the drilling and roof cutting technology has the advantages of more drilling number, high cost, high construction strength and long time consumption in construction. Therefore, a new water jet continuous roof cutting method for mines is urgently needed to be proposed.
According to the existing water jet cutter specification, the pressure of the sand-adding water jet cutter can exceed 400MPa, the range under the unobstructed condition exceeds 400m, and the top plate with the depth of tens of meters can be cut under the circular reciprocating cutting. Therefore, the invention provides a method for cutting the top by using a self-moving high-pressure water jet cutter, which adopts a high-pressure water jet cutter cutting technology, continuously and completely cuts the top, has controllable direction and does not change the physical and chemical properties of the coal rock mass; the material is safe in nature, does not generate harmful substances, and does not induce derived disasters; the method is safe and environment-friendly, high in top cutting speed and high in efficiency, can adapt to top cutting work under various complex conditions, and can well solve disasters caused by inherent properties of thick hard top plates.
Disclosure of Invention
The invention provides a mobile water jet cutting continuous top cutting method for a mine, which aims to effectively solve the problems of limited application range and non-ideal top cutting effect of the existing top cutting method.
The method comprises the following steps:
s1: according to the field requirement, core drilling holes are constructed on the tunneling working face, the distance and the diameter of the drilling holes are determined according to the field geological conditions, the angle and the length of the drilling holes are consistent with those required by roof cutting, and the mechanical property of the rock mass cored by the drilling holes is identified;
s2: adopting a movable water jet cutting continuous topping process to cut the top plate in the working face excavation roadway along the drilling connecting line, and adjusting the caliber and angle of the cutter head and the pressure, flow and water-sand ratio of water flow according to the mechanical property of the top plate rock mass obtained in S1;
s3: in the top cutting process, a deep hole peeping instrument is used for observing the cutting depth and effect, and revision parameters are provided for the next step of circular cutting and the next step of cutting;
s4: after the top cutting work of the stage is finished, supporting the top plate of the stage, and then tunneling the next stage, after the tunneling, the top cutting and the supporting of the roadway are finished, stoping the working face, and meanwhile, processing the stoping roadway of the next working face;
s5: and (5) circulating construction until the coal seam mining is finished.
The mechanical property identification in S1 includes uniaxial tensile strength, uniaxial compressive strength, elastic modulus, Poisson' S ratio, fracture toughness and the like.
The cutting pitch cut in S2 is the tunneling footage.
The water jet cutter head used in the S2 is a telescopic cutter head, the cutting caliber of the water jet cutter is larger than that of the cutter head, and the cutter head penetrates into the cutting gap in the cutting process to carry out the next stage of circular cutting.
In S2, according to the mechanical properties of a roof rock mass, if the rock stratum belongs to a thick hard rock stratum (generally, the compressive strength of a single shaft exceeds 60Mpa, and the thickness exceeds 10m), and the shock resistance is strong, a small-caliber cutter head is used to increase the water flow pressure, reduce the cutting angle and avoid a step-type lower layer of the hard rock stratum after cutting is finished; otherwise, the soft rock stratum is thin and the texture is weak, the large-caliber cutter head is used, the water flow pressure is reduced, the cutting angle is increased, and the cutting tool naturally collapses.
Wherein, the caliber of the water jet cutter head is generally 0.25-1 mm, the caliber of the small caliber is generally not more than 0.5mm, the water flow pressure is generally 200-400 MPa, the cutting angle is generally 45-90 degrees, for thick and hard rock strata, the cutting angle is generally not more than 60 degrees, and for soft rock strata is generally more than 60 degrees.
And S3, the drilling peeping instrument is placed in the core drilling hole to observe the vertex depth and the vertex effect. If the top cutting depth and the effect are not expected, revising parameters by adopting a relevant adjusting method aiming at the thick and hard rock stratum; if the cutting effect exceeds the expectation, revising the parameters by adopting a relevant adjusting method aiming at the weak rock stratum; if the expected effect is met, the parameter is continuously used. The process is a dynamic adjustment process, and may need to be dynamically adjusted several times to achieve the desired effect.
The tunneling-roof cutting-supporting in the S4 process is a complete sequence process.
S2, S4 and S5 are a cyclic reciprocating process until the coal seam is completely mined.
In the continuous roof cutting method, after a working face roadway is tunneled to complete a footage, the working face is constructed, water jet cutting and roof cutting are carried out on the working face, then supporting is carried out, and the tunneling footage completion construction is completed, and the continuous roof cutting method is a sequential process: the water jet cutting top technology is used for continuously cutting the top plate and can perform circular reciprocating cutting according to a real-time observation result until the cutting depth is reached.
The technical scheme of the invention has the following beneficial effects:
in the scheme, the self-moving high-pressure water jet cutting method is adopted, so that the roof can be continuously and completely cut, the direction is controllable, and the physical and chemical properties of the coal rock mass are not changed; the material is safe in nature, does not generate harmful substances, and does not induce derived disasters; the method is safe and environment-friendly, high in top cutting speed and high in efficiency, can adapt to top cutting work under various complex conditions, and can well solve disasters caused by inherent properties of thick hard top plates.
Drawings
FIG. 1 is a schematic diagram showing the effect of the mobile water jet cutting continuous top cutting method for mines according to the invention;
FIG. 2 is a schematic cross-sectional view of the effect of the topping method of the present invention;
FIG. 3 is a schematic view of the topping process of the present invention;
fig. 4 is a schematic structural view of a water jet cutter according to the present invention.
Wherein: 1-self-moving water jet cutting equipment; 2, a self-moving water jet equipment crawler; 3, a self-moving water jet equipment control platform; 4, a water jet cutter head of the self-moving water jet cutter device; 5, a bottom plate; 6-coal bed; 7-a top plate; 8, cutting a gap by a water jet; 9, tunneling a roadway; 10, coring and drilling; 11, repeatedly and circularly cutting the top plate by self-moving water jet equipment; 12-roadway driving direction; 13-cutting the gap in the unfinished cutting area; 14-a water tank; 15-an accumulator; 16-a controller; 17-a supercharger; 18-high pressure water flow; 19-a high pressure pump; 20-a sand adding device; 21-a hydraulic device; 22-pressure gauge; 23-water flow line.
Detailed Description
In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.
The invention provides a mobile water jet cutting continuous top cutting method for a mine.
The method comprises the following steps:
s1: constructing a plurality of core drill holes on a tunneling working face, determining the distance and the diameter of the drill holes according to field geological conditions, and identifying the mechanical properties of the rock mass cored by the drill holes, wherein the angles and the lengths of the drill holes are consistent with those required by roof cutting;
s2: a working face is tunneled, a movable water jet cutting continuous topping process is adopted to cut the top plate along a drilling connecting line, and the caliber and the angle of a cutter head and the pressure, the flow and the water-sand ratio of water flow are adjusted according to the mechanical property of the top plate;
s3: in the top cutting process, a deep hole peeping instrument is used for observing the cutting depth and effect, and revision parameters are provided for the next step of circular cutting and the next step of cutting; observing whether the cutting height reaches a preset height according to the drilling peeking result, and adjusting parameters such as pressure, water-sand ratio and the like in the next stage or during circular cutting to strive to achieve the most economical and practical purposes;
s4: after the top cutting work of the stage is finished, supporting the top plate of the stage, and then tunneling the next stage, after the tunneling, the top cutting and the supporting of the roadway are finished, stoping the working face, and meanwhile, processing the stoping roadway of the next working face;
s5: and (5) circulating construction until the coal seam mining is finished.
The following description is made with reference to specific embodiments.
As shown in fig. 1 and fig. 2, the method comprises the following steps:
s1: constructing a plurality of core drill holes 10 in a tunneling roadway 9 of a coal seam 6, determining the distance and the diameter of the core drill holes 10 according to site geological conditions, and identifying the mechanical properties of the rock mass cored by the core drill holes 10, wherein the angle and the length of the core drill holes 10 are consistent with those required by roof cutting;
it is noted that the coring drilling intervals are typically multiples of the cutting stage interval, with the coal seam 6 being the roof 7 and floor 5 respectively above and below. Generally, in order to find out the distribution condition of thick and hard rock stratums in a top plate, the coring and drilling construction depth is large, the vertical distance generally exceeds 100m, the position of the thick and hard rock stratum (generally, a plurality of thick and hard rock stratums) is found through the coring and drilling imaging technology and the rock mechanical property test, and the height of the generally uppermost thick and hard rock stratum is the water jet cutting depth; for thick and hard rock strata, the cutting angle of the water jet cutter is 60 degrees; conversely, the cutting angle may be increased appropriately. The spacing of the core drill holes is not fixed, the core drill holes are constructed in the area with large structural or geological condition change, generally one core drill hole is constructed at intervals of 300m, or the spacing can be reduced for better verifying the cutting effect, or small-spacing drill hole observation can be concentrated in a special area.
S2: a working face excavation roadway 9 cuts a top plate 7 by adopting a continuous topping process of a self-moving water jet device 1 along a connecting line of core drilling holes 10, and parameters such as the caliber and the angle of a cutter head and the pressure, the flow, the water-sand ratio and the like of water flow are adjusted according to the mechanical properties of the top plate;
the topping parameters can be revised and adjusted in real time and can be adjusted according to the mechanical properties of the rock measured in S1 and the condition of the coring drill hole 10 in S3; for a thick and hard rock stratum (the compressive strength of a common single shaft exceeds 60MPa, the thickness exceeds 10m), the shock resistance is strong, a small-caliber cutter head (generally 0.25-0.5 mm) is used, the water flow pressure is increased (generally not less than 300MPa), the cutting angle is reduced (generally 45-60 degrees), and a step-type lower layer of the hard rock stratum after cutting is avoided; otherwise, the weak rock stratum uses a large-caliber cutter head (generally not less than 0.5mm), reduces the water flow pressure (generally not more than 300MPa), increases the cutting angle (generally 60-90 degrees), and naturally collapses. The used water jet scalpel head is a telescopic scalpel head, the cutting caliber of a common water jet scalpel is slightly larger than that of the scalpel head, and the scalpel head can penetrate into the cutting gap 13 of the unfinished cutting area in the cutting process to perform the next-stage circular cutting.
And (3) repeatedly and circularly cutting the top plate 11 by the self-moving water jet equipment along the roadway tunneling method 12.
S3: in the top cutting process, a deep hole peeping instrument is used for observing the water jet cutting gap 8 and the effect, and revision parameters are provided for the next step of circular cutting and the next stage of cutting work;
the drilling peep instrument is used for observing the depth and the effect of the top plate 7 in the core drilling hole 10, namely the core drilling hole is the peep drilling hole.
S4: after the top cutting work of the stage is finished, supporting the top plate of the stage, and then tunneling the next stage, after the tunneling, the top cutting and the supporting of the roadway are finished, stoping the working face, and meanwhile, processing the stoping roadway of the next working face;
s5: and (5) circulating construction until the coal seam mining is finished.
In S4, roadway tunneling, roof cutting and supporting are a complete sequential process; s2, S4 and S5 are a cyclic reciprocating process until the coal seam is completely mined.
As shown in fig. 3, in the specific topping control, the water tank 14 is connected to the high-pressure pump 19 through the water flow line 23, the high-pressure pump 19 is connected to the self-moving water jet device water jet head 4 through the energy accumulator 15 and the controller 16, meanwhile, the hydraulic device 21 is connected to the self-moving water jet device water jet head 4 through the supercharger 17, the sand adding device 20 is connected to the self-moving water jet device water jet head 4, and the high-pressure water flow 18 is ejected from the self-moving water jet device water jet head 4. Wherein, the hydraulic device 21 is provided with a pressure gauge 22.
As shown in fig. 4, the self-moving water jet cutting equipment crawler 2 is arranged at the lower part of the self-moving water jet cutting equipment related by the invention, the self-moving water jet cutting equipment control platform 3 is arranged above the self-moving water jet cutting equipment crawler 2, and the self-moving water jet cutting equipment control platform 3 is connected with the self-moving water jet cutting equipment head 4.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (7)
1. A mobile water jet cutting continuous top cutting method for a mine is characterized by comprising the following steps:
s1: according to the field requirement, core drilling holes are constructed on the tunneling working face, the distance and the diameter of the drilling holes are determined according to the field geological conditions, the angle and the length of the drilling holes are consistent with those required by roof cutting, and the mechanical property of the rock mass cored by the drilling holes is identified;
s2: adopting a movable water jet cutting continuous topping process to cut the top plate in the working face excavation roadway along the drilling connecting line, and adjusting the caliber and angle of the cutter head and the pressure, flow and water-sand ratio of water flow according to the mechanical property of the top plate rock mass obtained in S1;
s3: in the top cutting process, a deep hole peeping instrument is used for observing the cutting depth and effect, and revision parameters are provided for the next step of circular cutting and the next step of cutting;
s4: after the top cutting work of the stage is finished, supporting the top plate of the stage, and then tunneling the next stage, after the tunneling, the top cutting and the supporting of the roadway are finished, stoping the working face, and meanwhile, processing the stoping roadway of the next working face;
s5: and (5) circulating construction until the coal seam mining is finished.
2. The mobile water jet continuous topping method for mine of claim 1 wherein the mechanical property identification in S1 comprises uniaxial tensile strength, uniaxial compressive strength, elastic modulus, poisson' S ratio, fracture toughness.
3. The mobile water jet continuous topping method for mine according to claim 1, wherein the cutting pitch of the cutting in S2 is a tunneling cut.
4. The method for continuous mining with a movable water jet cutter according to claim 1, wherein the water jet cutter head used in S2 is a retractable cutter head, the cutting diameter of the water jet cutter is larger than that of the cutter head, and the cutter head is inserted into the cutting gap during cutting to perform the next stage of cyclic cutting.
5. The mobile water jet continuous topping method for mine according to claim 1, wherein the drill hole peeping instrument in S3 is placed in a core drill hole to observe the topping depth and effect.
6. The mobile water jet continuous topping method for mine according to claim 1, wherein the roadway driving-topping-supporting in S4 is a complete sequential process.
7. The mobile water jet continuous topping method for mine according to claim 1 wherein, the steps S2, S4, S5 are a cyclic reciprocating process until the coal seam is completely mined.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111384589.6A CN114198101A (en) | 2021-11-19 | 2021-11-19 | Mobile water jet cutting continuous top cutting method for mine |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111384589.6A CN114198101A (en) | 2021-11-19 | 2021-11-19 | Mobile water jet cutting continuous top cutting method for mine |
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| CN114198101A true CN114198101A (en) | 2022-03-18 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1642012A1 (en) * | 1989-05-29 | 1991-04-15 | Ленинградский горный институт им.Г.В.Плеханова | Method of supporting a development working |
| CN104625970A (en) * | 2014-12-20 | 2015-05-20 | 天津艾浮瑞特科技有限公司 | Mining mobile type power-supply-free water cutter |
| CN107816352A (en) * | 2017-10-16 | 2018-03-20 | 安徽理工大学 | A kind of method of the hard thick top plate pressure relief erosion control of waterpower cutting |
| CN112081570A (en) * | 2020-10-23 | 2020-12-15 | 河南理工大学 | Coal seam roof directional joint cutting equipment based on hydraulic cutting technology |
| CN112901166A (en) * | 2021-03-29 | 2021-06-04 | 中国矿业大学 | Thick coal seam hydraulic fracturing roof cutting gob-side entry retaining method |
-
2021
- 2021-11-19 CN CN202111384589.6A patent/CN114198101A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1642012A1 (en) * | 1989-05-29 | 1991-04-15 | Ленинградский горный институт им.Г.В.Плеханова | Method of supporting a development working |
| CN104625970A (en) * | 2014-12-20 | 2015-05-20 | 天津艾浮瑞特科技有限公司 | Mining mobile type power-supply-free water cutter |
| CN107816352A (en) * | 2017-10-16 | 2018-03-20 | 安徽理工大学 | A kind of method of the hard thick top plate pressure relief erosion control of waterpower cutting |
| CN112081570A (en) * | 2020-10-23 | 2020-12-15 | 河南理工大学 | Coal seam roof directional joint cutting equipment based on hydraulic cutting technology |
| CN112901166A (en) * | 2021-03-29 | 2021-06-04 | 中国矿业大学 | Thick coal seam hydraulic fracturing roof cutting gob-side entry retaining method |
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