CN109238056B - Charging hole sealing method for top plate deep hole presplitting blasting - Google Patents
Charging hole sealing method for top plate deep hole presplitting blasting Download PDFInfo
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- CN109238056B CN109238056B CN201811318308.5A CN201811318308A CN109238056B CN 109238056 B CN109238056 B CN 109238056B CN 201811318308 A CN201811318308 A CN 201811318308A CN 109238056 B CN109238056 B CN 109238056B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
- F42D1/08—Tamping methods; Methods for loading boreholes with explosives; Apparatus therefor
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D1/00—Blasting methods or apparatus, e.g. loading or tamping
- F42D1/08—Tamping methods; Methods for loading boreholes with explosives; Apparatus therefor
- F42D1/18—Plugs for boreholes
Abstract
The invention discloses a charging hole sealing method for top plate deep hole presplitting blasting, which comprises a rubber hole sealing device, an anchor rod anchoring agent, explosive roll groups, explosive rolls, a push rod and an initiator, wherein a secondary detonating cord and a plastic-sealed steel wire rope are installed at the tail end of explosive in the last explosive roll of each explosive roll group, the plastic-sealed steel wire rope transversely penetrates through a winding drum, each secondary detonating cord is connected with a main detonating cord in parallel, the head and the tail ends of the main detonating cord are respectively bound on the first explosive roll of the first explosive roll group and the last explosive roll of the last explosive roll group, an electric detonator is installed at the tail end of the explosive in the last explosive roll of the last explosive roll group, the electric detonator is connected with an explosion bus, and the explosion bus sequentially penetrates through the anchor rod anchoring agent and the capsule hole sealing device to be led out of a blast hole and is. The invention has the advantages of less material consumption, less time and less labor consumption for charging and sealing, recoverable pressure relief of the capsule hole sealing device after blasting, low cost, and good hole sealing effect due to the occurrence of the phenomena of hole pulling and perforation.
Description
Technical Field
The invention relates to the technical field of top plate deep hole pre-splitting blasting hole sealing, in particular to a charging hole sealing method for top plate deep hole pre-splitting blasting.
Background
With the successive deep mining of coal mines in China, the intensity and frequency of dynamic disasters of the coal mine roof are obviously increased due to the complex deep mechanical environment and the change of the mechanical properties of coal rocks. According to relevant data statistics, the percentage of the number of the top plate accidents and the number of dead people in all kinds of accidents in coal mines is large, and the top plate accidents and the dead people are key prevention and control objects in the coal mine accidents.
With the increase of the coal mining intensity and the increase of the range of the underground stope, if the hard roof above the coal seam can not be pushed along with the working face to collapse in time, the hard top plate bends and sinks under the self-weight action of the overlying rock stratum, and due to the supporting action of the coal wall of the working surface, the conversion from potential energy to kinetic energy is completed in the processes of slow bending sinking and breaking and caving, and the conversion acts on a supporting point close to the goaf, so that large stress concentration is generated in the coal wall close to the working surface, under the action of concentrated stress, the three-dimensional stress balance state inherent in the coal body is changed, when the coal body in the coal wall of the working face is seeking new balance, because the concentrated stress is far greater than the supporting capacity of the coal body, and the free surface of the working surface or the roadway cannot effectively restrict the internal movement of the coal body, the coal body can be quickly thrown out to the working surface or the roadway instantly to form rock burst. In order to reduce the danger of rock burst and avoid the occurrence of rock burst, the condition that the top plate accumulates energy needs to be changed or the continuous energy transmission capacity of the top plate needs to be damaged, a top plate deep hole pre-splitting blasting means is adopted, a plurality of blasting holes are constructed, after explosives are filled in the blasting holes, the explosives are sealed outside the explosives, then the explosives in the holes are detonated, the blasting pressure relief of the top plate is realized, and the danger of the rock burst is reduced.
The traditional explosive charging and hole sealing process is to charge explosive and then to charge sealing material. The method comprises the steps of firstly loading an explosive into a specified position in a blast hole, connecting the explosive with a detonating cord, then loading a plugging material and tamping, wherein the plugging material is clay, cement, an anchor rod anchoring agent and the like, the plugging length is not less than one third of the hole depth, one end of the detonating cord penetrates through the plugging material and is led out of the blast hole opening, an electric detonator is installed 1m inwards from the blast hole opening and is sealed by sealing the hole with the clay, a leg wire of the electric detonator is connected with an initiator positioned outside the blast hole, and the initiator is detonated after being electrified. However, in the hole sealing mode, all the plugging materials are used for sealing holes, if the plugging materials are used as anchor rod anchoring agents, 1 blast hole with the diameter of 89mm and the hole depth of 35m is sealed, 6 boxes of anchor rod anchoring agents (25 kg/box) are needed, 5 workers use the hole sealing method for about 80min, the labor efficiency is low, and the cost is high. In addition, water flows out of the blasting holes due to the fact that water tricks on the top plate in drilling of the individual sandstone top plate, and the traditional hole sealing mode that all the plugging materials are used for sealing holes easily causes the phenomenon of hole punching by pulling out the blasting holes, namely, the blasting materials do not penetrate out of the holes from the blasting holes to crush the burst surrounding rocks due to insufficient plugging resistance when the explosives explode, and the explosives do not play a blasting role in the surrounding rocks in the plugging areas, so that the hole sealing effect is poor.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides the charging and hole sealing method for the top plate deep hole presplitting blasting, which has the advantages of less charging and hole sealing materials, less time and less labor, can reduce the production cost, avoids the phenomenon of hole sealing by pulling out a gun, and has good hole sealing effect.
In order to achieve the purpose, the invention provides a charging hole sealing method for top plate deep hole presplitting blasting, which comprises a rubber hole sealing device, an anchor rod anchoring agent, explosive roll groups, explosive rolls, a push rod and an initiator, wherein each explosive roll group consists of a plurality of explosive rolls, each explosive roll consists of a roll and explosive filled in the roll, one end of each roll is provided with a threaded inner hole, the other end of each roll is provided with an external thread, and the explosive rolls are assembled and connected end to end through the threaded inner holes and the external threads, and the method specifically comprises the following steps:
a, prefabricating a plurality of cartridges with matched sizes and explosive dosages according to the aperture of construction blasting and the selected explosive type;
b, a plurality of cartridges are connected end to end through threaded inner holes and external threads to form a cartridge group, a steel wire rope and an auxiliary detonating cord are installed in the tail end of explosive in the last cartridge of each cartridge group, the steel wire rope transversely penetrates through the winding drum, each auxiliary detonating cord is connected in parallel to a main detonating cord, the head end of the main detonating cord is bound to the first cartridge of the first cartridge group, and the tail end of the main detonating cord is bound to the last cartridge of the last cartridge group;
c, arranging an electric detonator in the last explosive roll of the last group of explosive roll groups, wherein the electric detonator is connected with the head end of the blasting bus;
d, pushing the explosive roll group to a specified depth of the blasting hole by using a push rod, clamping the explosive roll group in the blasting hole through a plastic-sealed steel wire rope to prevent the explosive roll group from sliding downwards, fixing the position of the explosive roll group, and leading the tail end of a blasting bus out of the blasting hole and connecting the tail end of the blasting bus with an initiator positioned outside the blasting hole;
e, a plurality of rolls of anchor rod anchoring agent are taken as a group, the anchor rod anchoring agent is put into water for soaking after being bundled, the anchor rod anchoring agent is sent into the blast hole by a push rod and tamped after the soaking is finished, and at the moment, the last roll of the last group of roll groups is connected with the anchor rod anchoring agent;
and F, placing the rubber hole packer into the blast hole, connecting the rubber hole packer with a hydraulic pipeline, connecting a pressure relief valve and a pressure gauge for observing pressure change of the hole packer at the front end of a liquid supply valve of the hydraulic pipeline, injecting and pressurizing the rubber hole packer to carry out hole sealing, and detonating after the anchor rod anchoring agent is solidified for 90 min.
Compared with the prior art, the invention has the following advantages:
1. the method adopts the anchor rod anchoring agent to be matched with the rubber hole sealing device for hole sealing, the use amount of the anchor rod anchoring agent is reduced due to the use of the rubber hole sealing device, 6 boxes of anchor rod anchoring agent are needed to be used in the traditional method, while only 2 boxes of anchor rod anchoring agent are needed to be used in the method, the use cost of the anchor rod anchoring agent and the field labor intensity of workers are reduced, if 1 blast hole with the diameter of 89mm and the hole depth of 35m is plugged, 3 workers are needed for single hole sealing, and each worker saves 35min compared with the traditional hole sealing method, the time cost and the production cost of an enterprise are greatly saved, and the economic benefit of the enterprise is effectively improved.
2. According to the invention, the hole sealing is carried out by adopting the anchor rod anchoring agent to cooperate with the hole sealing of the rubber hole sealing device, the explosive and the rubber hole sealing device are separated by the anchor rod anchoring agent, the detonating cord is only used within the length range of the explosive cartridge group and does not pass through the rubber hole sealing device, but the detonating cord is replaced by the blasting bus to pass through a gap between the rubber hole sealing device and the hole wall, so that the capsule and the iron end enclosure of the rubber hole sealing device are effectively prevented from being exploded and deformed by the explosive and the detonating cord, the capsule and the iron end enclosure of the rubber hole sealing device are protected, and the rubber hole sealing device and the blasting bus subjected to pressure relief after blasting can be recycled, so that the production; meanwhile, the phenomenon of gun pulling and perforation is avoided, and the hole sealing effect is good. If one hole packer seals 6 holes, the cost of the single-hole sealing is reduced by 4.3% by the rubber hole packer matching with the anchoring agent sealing method compared with the traditional all-anchoring agent sealing method, and if the reuse times are more, the economic benefit is improved more obviously.
3. After the explosive is filled, only 2 boxes of anchor rod anchoring agent are needed to be filled and tamped, and then the anchor rod anchoring agent is filled into the rubber hole sealing device to seal holes.
Drawings
FIG. 1 is a schematic representation of the use of the present invention;
in the figure: 1. the explosive cartridge comprises a main detonating cord, 2 explosive cartridges, 3 auxiliary detonating cords, 4 anchor rod anchoring agents, 5 electric detonators, 6 rubber hole packers, 7 blasting buses, 8 hydraulic pipelines and 9 blasting holes.
Detailed Description
The invention will be further explained with reference to the drawings.
The diameter of the top plate pre-splitting blasting hole 9 is 89mm, and the hole depth is 35 m.
As shown in fig. 1, a charging hole sealing method for roof deep hole presplitting blasting comprises a rubber hole sealing device 6, explosive cartridge groups, explosive cartridges 2, an anchor rod anchoring agent 4 and an initiator, wherein each explosive cartridge group consists of a plurality of explosive cartridges 2, each explosive cartridge 2 consists of a drum and explosive filled in the drum, one end of each drum is provided with a threaded inner hole, the other end of each drum is provided with an external thread, and the explosive cartridges 2 are assembled and connected end to end through the threaded inner holes and the external threads, wherein the explosive is a secondary coal mine allowable water-gel explosive, the electric detonator 5 is a coal mine allowable millisecond delay electric detonator, the rubber hole sealing device 6 is a coal safety type FKSL-90/16 water injection rubber hole sealing device which is 2000mm in length, 51 +/-0.5 mm in inner diameter, 69 +/-2 mm in outer diameter, 110mm in free state expansion range and 25mm in maximum compressive strength, the anchor rod anchoring agent 4 is JDMSS cement anchor rod anchoring agent (225 mm in length, diameter 32 mm).
The method comprises the following specific steps:
the size and the dosage of the A prefabricated medicated roll 2 are as follows: length, diameter, weight, 300mm, 60mm, 0.8Kg, single-hole loading of 32Kg, and loading length of 12 m;
b, every 5 cartridges 2 are connected end to end through threaded inner holes and external threads to form a cartridge group, a plastic-sealed steel wire rope and an auxiliary detonating cord 3 are installed in the explosive tail end (the lower part in a figure 1 is the tail end) in the last cartridge 2 in each cartridge group, the plastic-sealed steel wire rope is a plastic-sealed steel wire rope with the diameter of 6mm and the length of 110mm, the plastic-sealed steel wire rope transversely penetrates through a winding drum and can be clamped in a detonating hole 9, each auxiliary detonating cord 3 is 200mm in length and is connected to a main detonating cord 1 in parallel, the head end of the main detonating cord 1 is bound to the first cartridge 2 in the first cartridge group, the tail end of the main detonating cord 1 is bound to the last cartridge 2 in the last cartridge group, and the main detonating cord 1 and the auxiliary detonating cord 3 are fastened to the cartridges 2 through adhesive tapes;
c, arranging an electric detonator 5 in the last explosive roll 2 of the last group of explosive roll groups, wherein the electric detonator 5 is connected with the head end of a blasting bus 7;
d, pushing the explosive coil group to a specified depth of the blasting hole 9 by using a push rod, clamping the explosive coil group in the blasting hole 9 through a plastic-sealed steel wire rope, fixing the position of the explosive coil group, and leading the tail end of the blasting bus 7 out of the blasting hole 9 and connecting the blasting bus with an initiator positioned outside the blasting hole 9;
e, every 5 rolls of anchor rod anchoring agents 4 are taken as one group, 28 groups of anchor rod anchoring agents are needed, the anchor rod anchoring agents are tied up by using transparent adhesive tapes and are placed into water to be soaked for 40s, after the soaking is finished, the anchor rod anchoring agents 4 are sent into the blasting holes 9 by using a push rod and are tamped, the total length after the tamping is 2m, and at the moment, the last explosive roll 2 of the last group of explosive rolls is connected with the anchor rod anchoring agents 4;
f, placing the rubber hole packer 6 into the blast hole 9, connecting the rubber hole packer with the hydraulic pipeline 8, connecting a pressure relief valve and a pressure gauge for observing pressure change of the hole packer at the front end of a liquid supply valve of the hydraulic pipeline 8, injecting liquid into the rubber hole packer 6 for pressurization, stopping when the pressure reaches 18Mpa, and detonating the electric detonator 5 and detonating explosive through the detonator after the anchor rod anchoring agent is solidified for 90 min.
The charging hole sealing method effectively avoids the occurrence of gun-pulling perforation phenomenon, simultaneously effectively avoids explosion deformation of a capsule and an iron end socket of the rubber hole sealing device 6 caused by a detonating cord, the pressure relief of the rubber hole sealing device 6 after explosion can be recycled, and one hole sealing device can be recycled for at least 6 times according to a field hole sealing experiment.
From the benefit analysis view: the traditional hole sealing method needs 6 boxes of anchor rod anchoring agent 4, the time for filling 6 boxes of anchor rod anchoring agent 4 in the traditional hole sealing mode is 1.33 hours, the hole sealing method needs 2 boxes of anchor rod anchoring agent 4, the time for filling 2 boxes of anchor rod anchoring agent 4 is about 30-33 minutes, the time for installing a connecting pipeline of a rubber hole sealing device 6 to a specified position and the time for pressing the connecting pipeline to 18Mpa is 8-12 minutes, the total time is 0.75 hour, and the further analysis is as follows:
the traditional hole sealing method of all the anchoring agents has the following cost:
6 boxes 70 elements/box +3 people 45 elements/hour 1.33 hours 600 elements
Wherein, 1.33 hours is the time for filling 6 boxes of anchoring agent in the traditional hole sealing mode.
According to 6 times of calculation of recycling of one rubber hole packer 6, the hole sealing method of the rubber hole packer 6 with the anchoring agent has the following single-hole sealing cost:
2 boxes 70 elements/box +3 people 45 elements/man-hour 0.75 hour +2000 elements/6 times 574 elements
Wherein, 0.75 hour is the time for loading the 2-box anchor rod anchoring agent and the rubber hole packer, and 2000 yuan is the price of the rubber hole packer.
Compared with the traditional hole sealing method of all the anchoring agents, the hole sealing method of the rubber hole sealing device 6 with the anchoring agent has the advantages that the single hole sealing cost is reduced by 26 yuan, and the cost is reduced by 4.3%.
If the time cost is considered, the value created by saving 35min for 3 workers is far more than 40 yuan; and the labor intensity of filling the anchoring agent on the site by 3 workers is greatly reduced.
Claims (6)
1. The utility model provides a powder charge hole sealing method for roof deep hole presplitting blasting, including rubber hole packer (6), stock anchor (4), cartridge group, cartridge (2), push rod and detonator, every cartridge group comprises a plurality of cartridges (2), cartridge (2) comprise the reel and fill the explosive in the reel, reel one end is provided with the screw thread hole, the other end is provided with the external screw thread, head and the tail are through screw thread hole, external screw thread be assembled between a plurality of cartridges (2), its characterized in that, specifically include following step:
a, prefabricating a plurality of cartridges (2) with matched sizes and explosive dosages according to the aperture of construction blasting and the selected explosive type;
b, a plurality of cartridges (2) are connected end to end through threaded inner holes and external threads to form a cartridge group, a plastic-sealed steel wire rope and an auxiliary detonating cord (3) are installed in the tail end of explosive in the last cartridge (2) of each cartridge group, the plastic-sealed steel wire rope transversely penetrates through a winding drum, each auxiliary detonating cord (3) is connected in parallel to a main detonating cord (1), the head end of the main detonating cord (1) is bound on the first cartridge (2) of the first cartridge group, and the tail end of the main detonating cord is bound on the last cartridge (2) of the last cartridge group;
c, arranging an electric detonator (5) in the last explosive roll (2) of the last group of explosive roll groups, wherein the electric detonator (5) is connected with the head end of a blasting bus;
d, pushing the explosive roll group to a specified depth of the blasting hole (9) by using a push rod, clamping the explosive roll group in the blasting hole (9) through a plastic-sealed steel wire rope to prevent the explosive roll group from sliding downwards, fixing the position of the explosive roll group, and leading the tail end of a blasting bus (7) out of the blasting hole (9) and connecting the tail end of the blasting bus (7) with an initiator positioned outside the blasting hole (9);
e, a plurality of rolls of anchor rod anchoring agents (4) are taken as a group, the anchor rod anchoring agents (4) are placed into water for soaking after being bundled, the anchor rod anchoring agents (4) are sent into the blast hole (9) by a push rod and tamped after soaking is finished, and at the moment, the last explosive roll (2) of the last group of explosive rolls is connected with the anchor rod anchoring agents (4);
f, placing the rubber hole packer (6) into the blast hole (9) and connecting the rubber hole packer with the hydraulic pipeline (8), connecting a pressure relief valve and a pressure gauge for observing pressure change of the hole packer at the front end of a liquid supply valve of the hydraulic pipeline (8), injecting liquid into the rubber hole packer (6) for pressurization to seal holes, and detonating a detonator and detonating explosive after the anchor rod anchoring agent (4) is solidified for 90 min.
2. A charging and hole sealing method for roof deep hole presplitting blasting according to claim 1, characterized in that the secondary detonating cord (3) and the primary detonating cord (1) are fastened on the cartridge (2) by using adhesive tape.
3. The method for charging and sealing the top plate deep hole pre-splitting blasting according to the claim 1 or 2, wherein in the step (D), the soaking time of the anchor rod anchoring agent (4) is 35s-40 s.
4. A charging and sealing method for the top plate deep hole presplitting blasting according to the claim 3, characterized in that in the step (E), the sealing is carried out by injecting liquid and pressurizing the rubber hole packer (6), and the sealing is stopped when the pressure reaches 18 Mpa.
5. The charging and sealing method for the top plate deep hole presplitting blasting according to the claim 3, characterized in that the rubber hole packer (6) is a coal safety FKSL-90/16 type rubber hole packer for water injection, the length of the hole packer is 2000mm, the inner diameter is 51 +/-0.5 mm, the outer diameter is 69 +/-2 mm, the expansion range in a free state is 110mm, and the maximum compressive strength is 25 MPa.
6. A charging and hole sealing method for top plate deep hole presplitting blasting according to claim 3, characterized in that the explosive is a secondary coal mine permitted water gel explosive, and the electric detonator is a coal mine permitted millisecond delay electric detonator.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811318308.5A CN109238056B (en) | 2018-11-07 | 2018-11-07 | Charging hole sealing method for top plate deep hole presplitting blasting |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811318308.5A CN109238056B (en) | 2018-11-07 | 2018-11-07 | Charging hole sealing method for top plate deep hole presplitting blasting |
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| CN109238056B true CN109238056B (en) | 2021-03-30 |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110274530B (en) * | 2019-07-18 | 2022-07-22 | 陕西正通煤业有限责任公司 | Method for sealing coal mine roof blast hole |
| CN112665473A (en) * | 2020-12-10 | 2021-04-16 | 中煤科工开采研究院有限公司 | Blasting hole sealing method |
| CN114441347B (en) * | 2021-12-29 | 2024-02-23 | 陕西正通煤业有限责任公司 | Method for measuring crack development radius of top plate deep hole pre-splitting blast hole |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US4660644A (en) * | 1986-01-31 | 1987-04-28 | Richard Egnor | Inflatable rubber blasting hole plug |
| CN201764916U (en) * | 2010-06-12 | 2011-03-16 | 中铁十六局集团有限公司 | Blast hole sealing plug |
| CN105066804B (en) * | 2015-07-16 | 2017-01-25 | 湖南辰州矿业有限责任公司 | Mine water stemming bag and application of mine water stemming bag in borehole blockage |
| CN108007288B (en) * | 2017-12-29 | 2019-06-28 | 煤炭科学技术研究院有限公司 | Powder charge method for sealing for underground coal mine deep hole top plate presplit blasting |
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