CN102735121A - Annular linear energy-accumulation cutter - Google Patents
Annular linear energy-accumulation cutter Download PDFInfo
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- CN102735121A CN102735121A CN201210230068XA CN201210230068A CN102735121A CN 102735121 A CN102735121 A CN 102735121A CN 201210230068X A CN201210230068X A CN 201210230068XA CN 201210230068 A CN201210230068 A CN 201210230068A CN 102735121 A CN102735121 A CN 102735121A
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Abstract
The invention belongs to the technical field of engineering blasting and discloses an annular linear energy-accumulation cutter. The annular linear energy-accumulation cutter comprises a restraining shell, explosives, liners and a detonation device, wherein the restraining shell is a columnar pipe; a plurality of semi-circular tubular linear liners are arranged inside the shell; notches of the pipes all face towards and are in contact with the inner wall surface of the shell; the outer walls of each two adjacent semi-circular tubes are in tangent mutually; the length of each tube is the same as the length of the restraining shell, and the axes of each tube and the restraining shell are in parallel; a middle space surrounded by the liners is filled with the explosives and is provided with a detonating fuse; the axis of the middle space is coincided with the axis of the restraining shell; the restraining shell and the liners are made of metal materials or plastic materials; and the explosives are common industrial explosives. The annular linear energy-accumulation cutter reasonably utilizes the energy of the explosives and can be used in excavating operation in coals or rocks and generate a plurality of cracks in the coals or the rocks; and the annular linear energy-accumulation cutter is particularly applicable to middle and deep hole pre-cracking blasting of coal seams and can effectively reduce or eliminate the danger of gas burst in the coal seams and prevent or reduce severe mining safety accidents such as gas burst or fire hazard.
Description
Technical field:
The invention belongs to the engineering explosion technical field.
Background technology:
The coal in China reserves are abundant, and distributed areas are wide, and geological conditions is relatively complicated, and the higher coalfield of gas bearing capacity is more.The colliery in the process of digging, in the very short time (several minutes), from rib inside to getting working face suddenly the phenomenon of a large amount of coals of ejection and gas be called coal and gas is given prominence to.It is fierce mine gas dynamic phenomenon, can spray a large amount of gas and coal petrography, can destroy the roadway facility, the personnel that cause suffocate, destroy mine ventilation system, even possibly cause great mine safety accidents such as gas explosion and fire incident.
Along with coal mining is extended to the deep, the gas bearing capacity in the coal seam is increasing, and the gas permeability in coal seam is reducing, and coal-bed gas is mobile obstructed in the extraction process, causes coal body gas to be difficult to leak, and makes coal body possibly keep higher gas pressure.If, will give prominence to probably in case expose suddenly.Therefore; When the coal seam of the high gas bearing capacity of low-permeable is exploited; It is outstanding to prevent that gas takes place in the getting working face progradation, and this just requires to change working face the place ahead stress in coal bed and distributes, and keeps the sufficiently long pressure zone that unloads; Improve simultaneously the gas permeability of coal body as far as possible, make coal-bed gas be able to abundant walkthrough.
People pass through test and research many times, have taked various outburst prevention measures.Major measure has: hydraulic flushing in hole, high-pressure hydraulic slot, the explosion of coal body water, leading major diameter bleeder off hole, metallic framework, remote shock blasting (inducing outstanding) draw out methane, measures such as cantilever timbering, deep hole standing.
Deep hole presplitting control standing can effectively reduce or eliminate the coal-bed gas outburst hazard.The purpose of in the coal containing methane gas body, carrying out deep hole presplitting control standing is crack length and scope in order to increase coal body, to improve the gas permeability of explosion coal body.Therefore, it is not only required in, and the line direction forms through crack between adjacent holes, and requires in other direction generation as much as possible crack, and making interior the formation with the big gun hole of coal body is the fracture network that the center is interconnected.
Deep hole presplitting control standing has obtained extensive use in coal mining.For example: provided a kind of coal mine gas extraction explosion powder column that is applicable to deep hole standing under the coal mine among the ZL200920173412.X; It is by the body of interior coaling ore deposit permitted explosive, primacord be connected plug and constitute, it is inconvenient that it has overcome the powder charge in deep hole blasting of existing permitted explosive for coal mine, the insecure shortcoming of propagation of explosion; Have detonate with explosion transfer performance reliable; Characteristics such as easy to operate, but this powder column explosive payload is big, can not make full use of the explosion energy of explosive.
Provided a kind of continuous multi-directional concentrated energy perforating bullet among the ZL201010182436.9, it uses conical liner, and blast back produces jet, can realize continuous multi-directional concentrated energy perforating easily, has the large aperture, height is worn dark advantage.But, do not help digging operation owing to can only in the coal seam, form hole.
Summary of the invention:
The objective of the invention is to,, hoop linear shaped cutter in a kind of hole that is made up of hoop linear shaped charge constitution is provided to the deficiency in the existing medium-length hole Pre-splitting Blasting Technique.It is easy to use, and explosive payload is little, and explosion energy is big, can artificially control the blast crack, the demolition effect that obtains expecting.
The object of the invention is realized by following technical scheme:
Hoop linear shaped cutter of the present invention comprises constraint shell, explosive, cavity liner and apparatus to cause bursting, it is characterized in that said constraint shell is a cylindrical tube, in cylindrical tube constraint shell, is provided with the linear cavity liner of a plurality of semicircle tubuloses; The breach of each semicircular pipe all retrains the internal face of shell towards cylindrical tube; Its breach end face contacts with the internal face of cylindrical tube constraint shell; Two adjacent semicircular pipe outer walls are tangent to each other, and the length of each semicircular pipe is identical with cylindrical tube constraint shell, and axis is parallel to each other; In the central space that cavity liner surrounded, be filled with explosive, and be provided with the primacord that apparatus to cause bursting is installed, the axis of this primacord coincides with the axis of constraint shell; Said constraint shell and cavity liner are processed by metal material or plastic material; The explosive of said filling is an industry explosive commonly used.
In practical application; The linear cavity liner of said semicircle tubulose also can be replaced by round tubular linear cavity liner; The external cylindrical surface of its pipe contacts with the internal face of cylindrical tube constraint shell; Adjacent pipe is tangent to each other, and the length of each round tube is identical with cylindrical tube constraint shell, and axis is parallel to each other.
When making hoop linear shaped cutter, according to the needs of use occasion confirm required constraint housing diameter, length and cavity liner quantity earlier in reality, confirm the cavity liner diameter according to cavity liner quantity then, confirm explosive payload at last again.Under common situation, the cavity liner quantity of use is more than or equal to 3, and its wall thickness is between 0.6-2mm.Before the filling explosive, should fix the position of each cavity liner earlier, guarantee that cavity liner can not move to guarantee the uniformity of filling explosive in the filling process.
The abundant reasonable use of hoop linear shaped cutter of the present invention explosive energy, it can satisfy the needs of different engineerings, for example the digging operation of coal body or rock.Its operation principle is: when adopting metal semicircle pipe or metal circular tube as cavity liner, explosive charge acts on cavity liner, makes its formation bullet and medium around the hoop is cut and form many linear holes with certain depth and width.This is because after detonating in the explosive center; Detonation wave is to propagating all around; Affact on the cumulative cavity liner; Cavity liner is crushed rapidly and to plane of symmetry motion, on the plane of symmetry, is formed the blade-like bullet of one high-speed motion, and whole jet cutter will form the blade-like bullet of a plurality of high-speed motions simultaneously.Hoop linear shaped cutter is exactly to utilize many hoops high speeds that produced, the blade-like metal bullet high-speed impact coal body or the rock of energy density to the effect of coal body or rock; In coal body or rock, forming with the big gun hole is many crackles at center; Reduced the pulverizing district that in coal body or rock, forms owing to explosive charge, thereby made demolition effect reach more excellent.When adopting plastics semicircle pipe or plastic round tube as cavity liner; Explosive converges to the plane of symmetry rapidly with the plastic round tube fusing, and with detonation gas after detonating; Produce the high-speed and high-temperature air-flow; Whole jet cutter will produce many coal body or the rocks around the high speed explosive gas wedge bump big gun hole simultaneously, forms many crackles at coal body or rock, thereby reaches the demolition effect of expection.
Jet cutter of the present invention uses explosive charge few, and the explosive utilization rate is high, and explosive can be fully used its detonation energy to circumferentially tangent semicircle tubulose cavity liner effect when producing detonative action.And the constraint shell not only can the fixing internal powder charge, and can play sealing process, thereby to prevent that corrosive substance from getting into the cavity liner inwall and it is produced to destroy reducing cumulative action.
Hoop linear shaped cutter of the present invention can be used in the digging operation of coal body or rock, forms many crackles at coal body or rock.Be specially adapted to the medium-length hole presplit blasting in coal seam, can effectively reduce or eliminate the coal-bed gas outburst hazard, prevent or reduce the generation of great mine safety accidents such as gas explosion and fire incident.
Below in conjunction with the accompanying drawing and the specific embodiment the present invention is further described.
Description of drawings
Fig. 1 be of the present invention have from all directions to semicircular rings to the embodiment of linear shaped cutter sketch map.
Fig. 2 is the vertical view of Fig. 1.
Fig. 3 is that the semicircular rings with ten directions of the present invention is to the embodiment of linear shaped cutter sketch map.
Fig. 4 is Fig. 3 vertical view.
Fig. 5 be of the present invention have from all directions to circular rings to the embodiment of linear shaped cutter sketch map.
Fig. 6 is the vertical view of Fig. 5.
Fig. 7 is that the circular rings with 12 directions of the present invention is to the embodiment of linear shaped cutter sketch map.
Fig. 8 is the vertical view of Fig. 7.
The specific embodiment
Referring to Fig. 1 and Fig. 2, constraint shell 1 is the plastic cylinder shape pipe of Φ 40mm, wall thickness 1mm, long 75mm, put into successively on the shell inner rim 8 with retrain the isometric red copper semicircle pipe 2 of shell, the diameter of every red copper semicircle pipe is Φ 16mm, thickness of pipe wall is 1mm.The centre of 8 red copper semicircle pipes is nitrolites 3, and its degree of packing is at 1.6g/cm
3-1.7g/cm
3In the scope.Detonator 4 is installed in the middle of the nitrolite, and the axis of this primacord coincides with the axis of constraint shell.
Eight of present embodiment is cut the 45# steel ingot to semicircle pipeline jet cutter to be tested: the processing diameter is the deep hole of 60mm on the 45# steel ingot; Above-mentioned this jet cutter is placed in the middle of this hole and detonates; The result is that to be formed uniformly the degree of depth on the hole wall of 45# steel ingot be 15mm, and diameter is 8 linear holes of 9mm.
Embodiment 20 to semicircular rings to the linear shaped cutter
Referring to Fig. 3 and Fig. 4, constraint shell 1 is Φ 50mm, thick 1mm, the plastic cylinder shape of long 75mm pipe is put into 10 Φ 16mm successively on the shell inner rim, thick 0.6mm, and with retrain the isometric plastic round tube of shell.With ammonium nitrate-fuel oil mixture 3 as main charge.Detonator 4 is installed in the middle of the ammonium nitrate-fuel oil mixture, and the axis of this detonator coincides available primacord direct initiation with the axis of constraint shell.
Ten of present embodiment is cut the 45# steel ingot to semicircle pipeline jet cutter to be tested: the processing diameter is the deep hole of 60mm on the 45# steel ingot; Above-mentioned this jet cutter is placed in the middle of this hole and detonates; The result is that on the hole wall of 45# steel ingot, to be formed uniformly the degree of depth be 13mm, and diameter is 10 linear holes of 7mm.
Referring to Fig. 5 and Fig. 6, constraint shell 1 is Φ 60mm, thick 0.7mm, the plastic cylinder shape of long 70mm pipe is put into 8 Φ 16mm successively on the shell inner rim, thick 1mm, and with retrain the isometric red copper pipe 2 of shell.With emulsion 3 as main charge.Detonator 4 is installed in the middle of the emulsion, and the axis of this detonator coincides available primacord 4 direct initiations with the axis of constraint shell.
Eight of present embodiment is cut the 45# steel ingot to circular rings to the linear shaped cutter to be tested: the processing diameter is the deep hole of 70mm on the 45# steel ingot; Above-mentioned this jet cutter is placed in the middle of this hole and detonates; The result is that on the hole wall of 45# steel ingot, to be formed uniformly the degree of depth be 23mm, and diameter is 8 linear holes of 12mm.
Embodiment 40 two to circular rings to the linear shaped cutter
Make hoop linear shaped cutter by Fig. 7 and Fig. 8, at Φ 50mm, thick 1.5mm puts into 12 Φ 10mm on plastic housing 1 inner rim of long 80mm successively, thick 1.5mm, and with constraint shell isometric plastic round tube 2.With emulsion 3 as main charge.Detonator 4 is installed in the middle of the emulsion, and the axis of this detonator coincides available primacord 4 direct initiations with the axis of constraint shell.
12 of present embodiment is cut the 45# steel ingot to circular rings to the linear shaped cutter to be tested: the processing diameter is the deep hole of 60mm on the 45# steel ingot; Above-mentioned this jet cutter is placed in the middle of this hole and detonates; The result is that on the hole wall of 45# steel ingot, to be formed uniformly the degree of depth be 16mm, and diameter is 12 linear holes of 7mm.
Above embodiment explanation, hoop linear shaped cutter of the present invention can normally detonate, and reaches the demolition effect of expection.Used various explosive for industrial (nitrolite, ammonium nitrate-fuel oil mixture, emulsion) are directly buied by market among the embodiment.
Claims (3)
1. a hoop linear shaped cutter comprises constraint shell, explosive, cavity liner and apparatus to cause bursting, it is characterized in that said constraint shell is a cylindrical tube, in cylindrical tube constraint shell, is provided with the linear cavity liner of a plurality of semicircle tubuloses; The breach of each semicircular pipe all retrains the internal face of shell towards cylindrical tube; Its breach end face contacts with the internal face of cylindrical tube constraint shell; Two adjacent semicircular pipe outer walls are tangent to each other, and the length of each semicircular pipe is identical with cylindrical tube constraint shell, and axis is parallel to each other; In the central space that cavity liner surrounded, be filled with explosive, and be provided with the primacord that apparatus to cause bursting is installed, the axis of this primacord coincides with the axis of constraint shell; Said constraint shell and cavity liner are processed by metal material or plastic material; The explosive of said filling is an industry explosive commonly used.
2. hoop linear shaped cutter as claimed in claim 1; It is characterized in that; The linear cavity liner of said semicircle tubulose is replaced by round tubular linear cavity liner, and the external cylindrical surface of its pipe contacts with the internal face of cylindrical tube constraint shell, and adjacent pipe is tangent to each other; The length of each round tube is identical with cylindrical tube constraint shell, and axis is parallel to each other.
3. hoop linear shaped cutter as claimed in claim 1 is characterized in that the cavity liner quantity of said use is more than or equal to 3, and its wall thickness is between 0.6-2mm.
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| CN201210230068XA CN102735121A (en) | 2012-07-05 | 2012-07-05 | Annular linear energy-accumulation cutter |
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| CN201210230068XA CN102735121A (en) | 2012-07-05 | 2012-07-05 | Annular linear energy-accumulation cutter |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103321669A (en) * | 2013-07-08 | 2013-09-25 | 中国矿业大学(北京) | Method for increasing permeability of low-permeability coal seam by means of deep-hole directional pre-splitting blasting |
| CN106767182A (en) * | 2017-03-23 | 2017-05-31 | 中国科学技术大学 | A kind of explosion switch based on multiaspect energy-gathering jetting |
| CN107726936A (en) * | 2017-11-08 | 2018-02-23 | 中国科学技术大学 | Self-enclosed spiral shape cumulative joint-cutting device |
| CN108225140A (en) * | 2018-02-09 | 2018-06-29 | 惠州市兴鲁节能科技有限公司 | A kind of parallel connection troughs for collecting energy double focusing energy means for loading |
| CN108759596A (en) * | 2018-05-25 | 2018-11-06 | 中国矿业大学 | A kind of flexibility cumulative charge pipe device and its application method |
| CN108867416A (en) * | 2018-07-04 | 2018-11-23 | 中国人民解放军陆军工程大学 | The large-scale circumferential cutter device of steel bridge cable member Double-layer flexible explosion |
| CN109099781A (en) * | 2018-11-08 | 2018-12-28 | 陕西沣采能源材料科技有限公司 | A kind of cumulative waterpower control explosion powder stick |
| CN109780952A (en) * | 2019-03-29 | 2019-05-21 | 中国人民解放军陆军工程大学 | Underwater explosion cumulative blasting device |
| CN109813191A (en) * | 2019-04-01 | 2019-05-28 | 中国矿业大学 | Coal petrography deep hole jet stream composite explosion protection pressure break integrated pipe and its application |
| CN115289926A (en) * | 2022-04-21 | 2022-11-04 | 北方爆破科技有限公司 | Assembled multidirectional energy-gathering cover and mounting method thereof |
| CN115289926B (en) * | 2022-04-21 | 2024-05-31 | 北方爆破科技有限公司 | Assembled multidirectional energy gathering cover and installation method thereof |
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Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103321669B (en) * | 2013-07-08 | 2015-05-27 | 中国矿业大学(北京) | Method for increasing permeability of low-permeability coal seam by means of deep-hole directional pre-splitting blasting |
| CN103321669A (en) * | 2013-07-08 | 2013-09-25 | 中国矿业大学(北京) | Method for increasing permeability of low-permeability coal seam by means of deep-hole directional pre-splitting blasting |
| CN106767182A (en) * | 2017-03-23 | 2017-05-31 | 中国科学技术大学 | A kind of explosion switch based on multiaspect energy-gathering jetting |
| CN106767182B (en) * | 2017-03-23 | 2018-07-03 | 中国科学技术大学 | A kind of explosion switch based on multi-panel energy-gathering jetting |
| CN107726936B (en) * | 2017-11-08 | 2023-08-29 | 中国科学技术大学 | Self-closing spiral energy-gathering joint cutter |
| CN107726936A (en) * | 2017-11-08 | 2018-02-23 | 中国科学技术大学 | Self-enclosed spiral shape cumulative joint-cutting device |
| CN108225140A (en) * | 2018-02-09 | 2018-06-29 | 惠州市兴鲁节能科技有限公司 | A kind of parallel connection troughs for collecting energy double focusing energy means for loading |
| CN108759596A (en) * | 2018-05-25 | 2018-11-06 | 中国矿业大学 | A kind of flexibility cumulative charge pipe device and its application method |
| CN108867416A (en) * | 2018-07-04 | 2018-11-23 | 中国人民解放军陆军工程大学 | The large-scale circumferential cutter device of steel bridge cable member Double-layer flexible explosion |
| CN109099781A (en) * | 2018-11-08 | 2018-12-28 | 陕西沣采能源材料科技有限公司 | A kind of cumulative waterpower control explosion powder stick |
| CN109780952A (en) * | 2019-03-29 | 2019-05-21 | 中国人民解放军陆军工程大学 | Underwater explosion cumulative blasting device |
| CN109780952B (en) * | 2019-03-29 | 2023-09-29 | 中国人民解放军陆军工程大学 | Underwater explosion energy-collecting cutting device |
| CN109813191A (en) * | 2019-04-01 | 2019-05-28 | 中国矿业大学 | Coal petrography deep hole jet stream composite explosion protection pressure break integrated pipe and its application |
| CN109813191B (en) * | 2019-04-01 | 2023-10-24 | 中国矿业大学 | Coal and rock deep hole jet flow composite explosion fracturing integrated pipe and application thereof |
| CN115289926A (en) * | 2022-04-21 | 2022-11-04 | 北方爆破科技有限公司 | Assembled multidirectional energy-gathering cover and mounting method thereof |
| CN115289926B (en) * | 2022-04-21 | 2024-05-31 | 北方爆破科技有限公司 | Assembled multidirectional energy gathering cover and installation method thereof |
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Application publication date: 20121017 |