CN109211037B - Underwater explosive cutter assembly and underwater explosive cutting method - Google Patents
Underwater explosive cutter assembly and underwater explosive cutting method Download PDFInfo
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- CN109211037B CN109211037B CN201811054980.8A CN201811054980A CN109211037B CN 109211037 B CN109211037 B CN 109211037B CN 201811054980 A CN201811054980 A CN 201811054980A CN 109211037 B CN109211037 B CN 109211037B
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- explosive
- cutter
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- underwater
- cutter assembly
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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
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
- F42B3/00—Blasting cartridges, i.e. case and explosive
- F42B3/22—Elements for controlling or guiding the detonation wave, e.g. tubes
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42D—BLASTING
- F42D3/00—Particular applications of blasting techniques
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
Abstract
The invention discloses an underwater explosive cutter assembly which comprises a plurality of explosive cutters and a waterproof inflatable rubber air bag, wherein each explosive cutter consists of a cutter shell, a metal energy-gathering cover and a high-energy explosive. The metal energy concentrating hood separates the interior of the cutter housing into an explosive chamber and an air chamber filled with high explosive. Its application method is also disclosed. The invention improves the practicability and flexibility of the explosive cutter and can be flexibly assembled aiming at the blasted object. The water-proof inflatable rubber bag is adopted to discharge water in the energy-gathering holes, so that the problem of poor energy-gathering cutting effect caused by the existence of water in underwater cutting blasting is solved. The energy-gathering cutter has the excellent characteristics of low cost, high efficiency, stability, reliability, convenience and flexibility, can effectively exert the advantages of the energy-gathering cutter, improves the working efficiency and reduces the construction cost.
Description
Technical Field
The invention relates to an underwater combined explosive cutter and a using method thereof, belonging to the field of engineering blasting and special blasting.
Background
The energy-gathering effect is that the energy of explosive detonation is gathered in the direction of a cavity by utilizing the cavity (also called energy-gathering cavity) at one end of an explosive package so as to improve the local destruction effect of the explosive. After the energy-gathered explosive bag is exploded, detonation products are gathered to the axis position of a cavity to form a high-speed, high-pressure and high-density energy-gathered jet flow, the speed of the jet flow can reach 1500-3000 m/s, the high-speed jet flow is up to pressure of hundreds of thousands to millions of atmospheres, and the target plate can be instantaneously damaged. Shaped charges have long been used to produce a wide variety of projectiles with high killing power. Then the energy-gathering effect is more and more widely applied to civil engineering. Shaped charges such as in oil perforation; energy-gathered blasting shock-excitation bomb in seismic exploration; linear shaped cutters for cutting sheet metal, cutting hulls when fishing sunken vessels, and the like.
The linear cutter develops from the initial military application to the civil economic construction, and particularly shows the advantages of high efficiency, quick operation, large cutting depth and strong safety in the demolition work of large steel structure buildings. At present, due to the demands of civil blasting engineering and military engineering, linear energy-gathering cutters are more and more widely applied underwater, such as the dismantling of an underwater drilling platform, the salvage of a sunken ship, the dismantling of an underwater structure of a steel structure bridge, the solving of the problem of drill sticking by blasting of an underwater blasting cutting bullet, and the like. However, due to the particularities of aqueous media, underwater application of a cumulative cutter is much more difficult than in air. Because parameters such as density, heat transfer speed, viscosity and the like of water are much larger than those of air, when the jet flow moves in water at high speed, the friction resistance is larger, the energy is more dispersed, and the speed of the head of the jet flow is lower than that of the air; the water has the functions of blocking and cooling the metal jet flow, and can also reduce the kinetic energy and the temperature of the jet flow and weaken the penetration capability of the jet flow. Another problem in underwater operations is how to attach the shaped charges to the object to be blasted, and due to the large differences in the various engineering conditions, the target geometry of the object to be blasted may be circular, square or elliptical, and the same shapes may also be of different sizes. Therefore, when construction is carried out, the traditional energy gathering cutting joint is redesigned aiming at specific engineering, the underwater blasting cutting operation efficiency and effect are reduced due to the problems, and the construction cost is increased.
In view of the above problems, the underwater explosive cutter should consider certain waterproof and pressure-resistant measures, so that the cutter is isolated from water, the pressure-resistant characteristic of the cutter and the like are also considered along with the difference of water depth, the diversity of field construction is also considered, the underwater explosive cutter also has strong applicability and flexibility, the advantages of the energy-gathering cutter can be effectively played, the working efficiency is improved, and the construction cost is reduced.
Disclosure of Invention
The invention aims to solve the problems that the defects in the prior art are overcome, the underwater explosion cutter assembly can be assembled according to different working conditions, the underwater explosion cutting operation difficulty is reduced, the underwater cutting performance is enhanced, the working period can be shortened and the workload is reduced in the large-scale steel structure dismantling operation. The invention also discloses a method for carrying out underwater explosive cutting by using the underwater explosive cutter assembly.
The invention relates to an underwater explosive cutter assembly which comprises a plurality of explosive cutters and a waterproof inflatable rubber air bag. The method is characterized in that: the explosive cutter consists of a cutter shell, a metal energy gathering cover and high-energy explosive.
The cutter shell is a door-shaped cross section profile, two front bottom corners are provided with serial positioning grooves, the serial positioning grooves are provided with inner serial positioning holes, two rear bottom corners are externally connected with serial positioning plates, and the serial positioning plates are provided with outer serial positioning holes.
The metal energy gathering cover is a V-shaped or W-shaped cross section profile, and is as long as the cutter shell. The metal energy-gathering cover is arranged in the cutter shell, the cutter shell is inverted in a V shape or a W shape (namely the sharp angle of the V shape or the W shape points to the top of the door shape of the cutter shell), the metal energy-gathering cover divides the interior of the cutter shell into an upper space and a lower space, the upper space is an explosive chamber and is filled with high-energy explosives, and the lower space is an inflation chamber (energy-gathering cavity in the general sense).
The top of the metal shell door-shaped cross section is a cone angle of 60-120 degrees.
The cross section of the metal energy gathering cover is V-shaped, the V-shaped vertex angle is 60-120 degrees, the height h is 10-100 mm, the width w is 6-170 mm, and the length l is 50-300 mm.
The metal energy gathering cover is made of copper, aluminum, tungsten-copper alloy or tungsten-nickel alloy.
The high-energy explosive should be TNT, or PBX, COMB, RDX, emulsion explosive and other high-energy density explosives with high detonation velocity and high brisance, and copper should ensure high charge density.
The high-energy explosive is pre-pressed and molded according to the shape and the size of the explosive chamber, and a preformed hole for installing a detonating cord is reserved at the top of the explosive during molding.
The method for implementing underwater explosion cutting by using the underwater explosion cutter assembly comprises the following steps: firstly, winding the waterproof inflatable rubber air bag on an object to be blasted; then, the explosive cutters are spliced to surround the object to be blasted and penetrate through a waterproof safety detonating cord, the plenum chamber covers of the explosive cutters are buckled on the waterproof inflatable rubber air bags, the waterproof inflatable rubber air bags are clamped into the plenum chambers of the explosive cutters, and the underwater explosive cutter assembly is assembled; the underwater explosion cutter assembly is sunk into a set explosion position along an object to be exploded by being suspended by a steel wire rope; inflating the waterproof inflatable rubber air bag until the inside of the inflatable chamber of the explosive cutter is filled; and finally, carrying out detonation operation.
The specific operation process of the underwater explosive cutter assembly used on site is as follows:
(1) assembling in a factory: according to the shape and the size of an object to be blasted in a construction site, selecting explosion cutters with proper size, determining the number of the explosion cutters required for surrounding the object to be blasted for one circle according to the diameter of the object to be blasted, and carrying out early-stage assembly on the explosion cutters, namely, firstly, according to half of the number of the explosion cutters required for surrounding the object to be blasted for one circle, serially connecting the explosion cutters into an explosion cutter group (namely, placing the serially connected positioning plate of one explosion cutter into the serially connected positioning groove corresponding to the other explosion cutter, and serially connecting the inner serially connected positioning hole and the outer serially connected positioning hole corresponding to the position by using a bolt), so that the explosion cutters are conveniently sleeved on the object to be.
(2) Field installation: the method comprises the steps of winding a circle of waterproof inflatable rubber air bag on an object to be blasted, connecting inflation pipes, connecting two groups of explosive cutter groups in series around the object to be blasted, covering an inflation chamber of each explosive cutter on the waterproof inflatable rubber air bag, and clamping the waterproof inflatable rubber air bag into the inflation chamber of the explosive cutter. And after the underwater explosion cutter assembly is assembled, the waterproof safety detonating cord is penetrated, and a steel wire rope is hung.
(3) And (3) sinking and fixing: and sinking the underwater explosive cutter assembly into a set position along the object to be blasted through a steel wire rope, and fixing the steel wire rope.
(4) And (3) inflation connection: and inflating the waterproof inflatable rubber air bag through the inflation tube, stopping inflating and plugging the inflation inlet after the waterproof inflatable rubber air bag is expanded to fully fill the inside of the inflation chamber of the explosive cutter, and connecting the detonating cord with the initiator.
(5) And (3) detonating operation: and detonating after the safety of the operation site is confirmed.
The underwater explosive cutter assembly and the underwater explosive cutting method have the advantages that: by adopting a combined design method, the practicability and the flexibility of the explosive cutter are improved, and the explosive cutter can be flexibly assembled aiming at the blasted objects with different shapes and sizes. The water-proof inflatable rubber bag is adopted to discharge water in the energy-gathering holes, so that the problem of poor energy-gathering cutting effect caused by the existence of water in underwater cutting blasting is solved. In conclusion, the underwater combined explosive cutter is an improvement on the structure of the traditional energy-gathering cutter and an innovation on the method, has the excellent characteristics of low cost, high efficiency, stability, reliability, convenience and flexibility, can effectively exert the advantages of the energy-gathering cutter, improves the working efficiency and reduces the construction cost.
Drawings
Fig. 1 is a front view of the detonation cutter of the present invention.
Fig. 2 is an isometric view of the detonation cutter of the present invention.
FIG. 3 is a schematic view of the waterproof inflatable rubber airbag of the present invention.
FIG. 4 is an assembly view of the explosive cutter assembly according to the present invention (the waterproof inflatable rubber airbag is not shown).
FIG. 5 is a schematic diagram of the application of the underwater combined explosion cutter in underwater explosion cutting of steel pipes.
Detailed Description
The embodiments of the present invention will be described in detail below with reference to the accompanying drawings by way of a preferred example.
Example (b): the invention relates to an underwater explosion cutter assembly and application thereof in underwater explosion cutting of a cylindrical steel pipe.
The embodiment takes the cylindrical steel pipe underwater explosion cutting as an example. The cylindrical steel pipe is used in underwater drilling platform, steel structure bridge, etc. and needs to be dismantled because the oil life reaches the design life. The outer diameter of the steel pipe 12 cut by the method is 300mm, the wall thickness is 10 mm, and the steel pipe is positioned underwater and needs to be subjected to underwater explosion cutting. According to the outer diameter of the steel pipe, 10 explosive cutters with the length of 10cm are selected.
The explosive cutter consists of a cutter shell 1, a metal energy gathering cover 2 and a high-energy explosive 3. The cutter shell 1 is a section bar with a door-shaped cross section, the top of the door-shaped cross section of the metal shell is a cone angle of 80 degrees, two front bottom corners of the metal shell 1 are provided with serial connection positioning grooves 5, the serial connection positioning grooves are provided with inner serial connection positioning holes, two rear bottom corners are externally connected with serial connection positioning plates 6, and the serial connection positioning plates are provided with outer serial connection positioning holes.
The metal energy-gathering cover 2 is a V-shaped cross section profile, the length of the profile is equal to that of the cutter shell (10 cm), the metal energy-gathering cover is made of copper, the thickness of the metal energy-gathering cover is 4 mm, the V-shaped vertex angle of the metal energy-gathering cover is 80 degrees, and the height of the metal energy-gathering cover is 50 mm. The metal energy-gathering cover is arranged in the cutter shell, the V shape is inverted (namely the V-shaped sharp angle points to the top of the door shape of the cutter shell), and the bottom of the metal energy-gathering cover extends outwards by 2-5 mm horizontally and is used for being fixed on the cutter shell 1.
The metal energy-gathering cover 2 divides the interior of the cutter shell 1 into an upper space and a lower space, wherein the upper space is an explosive chamber filled with high-energy explosives, and the lower space is a plenum chamber (energy-gathering cavity in the general sense). The high-energy explosive can be TNT, PBX, COMB, RDX, emulsion explosive and other high-energy density explosives. The high-energy explosive used in this example was selected to have a density of 1.63g/cm3TNT explosives. The high-energy explosive is pre-pressed and formed according to the shape and the size of the explosive chamber, and a reserved hole 4 for installing a detonating cord is reserved at the top of the explosive during forming.
Firstly, assembling 5 explosive cutters according to design parameters to form two explosive cutter groups respectively consisting of 5 explosive cutters. Namely: the tandem locating plate 6 of one explosive cutter is placed into the corresponding tandem locating groove 5 of the other explosive cutter, and the inner tandem locating hole and the outer tandem locating hole which correspond to each other in position are in tandem connection through the bolt 10. And secondly, winding a circle of water-proof inflatable rubber bag 7 on an exploded steel pipe 12, connecting an inflation pipe 11 on an inflation hole 8 of the water-proof inflatable rubber bag 7, sleeving the two groups of explosion cutter groups combined in the first step on the steel pipe 12, then connecting the two groups of explosion cutter groups, ensuring that the water-proof inflatable rubber bag 7 is positioned in an inflation chamber (energy-gathering hole) during connection, connecting and hanging steel wires on two sides of each explosion cutter group, and penetrating a waterproof safety detonating cord 13 to complete the assembly of the underwater explosion cutter assembly. The third step: the underwater explosion cutter assembly is sunk to a preset explosion position through a steel wire 9, and the upper end of the steel wire rope is fixed. Fourthly, the waterproof inflatable rubber air bag 7 is inflated through the inflation tube 11, and after the waterproof inflatable rubber air bag is expanded to fully fill the energy-gathering holes of the explosive cutter, the waterproof inflatable rubber air bag stops inflating and blocks the inflation port, and the detonating cord and the initiator are connected. Fifthly, detonating after the safety of the operation site is confirmed. After explosion, the steel pipe is cut and disconnected along the annular direction under the action of the energy-gathered jet flow, and the purpose of cutting the steel pipe from a preset position is achieved.
It should be understood that the illustrated embodiments are merely exemplary of the invention, and not all embodiments. All other embodiments that can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort fall within the protection scope of the present invention.
Claims (7)
1. An underwater detonation cutter assembly comprises a plurality of detonation cutters and a waterproof inflatable rubber air bag; the method is characterized in that: the explosion cutter consists of a cutter shell, a metal energy gathering cover and a high-energy explosive;
the cutter shell is a door-shaped cross section profile, two front bottom corners are provided with serial positioning grooves, the serial positioning grooves are provided with inner serial positioning holes, two rear bottom corners are externally connected with serial positioning plates, and the serial positioning plates are provided with outer serial positioning holes;
the metal energy gathering cover is a V-shaped or W-shaped cross section profile, and is as long as the cutter shell; the metal energy-gathering cover is arranged in the cutter shell, the cutter shell is inverted in a V or W shape, the metal energy-gathering cover divides the interior of the cutter shell into an upper space and a lower space, the upper space is an explosive chamber filled with high-energy explosives, and the lower space is a plenum chamber;
the explosive cutters are spliced to form a shape surrounding an exploded object, the plenum chamber covers of the explosive cutters are buckled on the waterproof inflatable rubber air bags, and the waterproof inflatable rubber air bags are clamped into the plenum chambers of the explosive cutters.
2. The underwater detonation cutter assembly of claim 1, wherein: the top of the door-shaped cross section is a cone angle of 60-120 degrees.
3. The underwater blast cutter assembly of claim 1 or 2, wherein: the cross section of the metal energy-gathering cover is V-shaped, the V-shaped vertex angle is 60-120 degrees, and the height h is 10-100 mm.
4. The underwater blast cutter assembly of claim 1 or 2, wherein: the metal energy gathering cover is made of copper, aluminum, tungsten-copper alloy or tungsten-nickel alloy.
5. The underwater detonation cutter assembly of claim 1, wherein: the high-energy explosive is TNT, PBX, COMB, RDX or emulsion explosive.
6. The underwater blast cutter assembly of claim 1 or 5, wherein: the high-energy explosive is pre-pressed and molded according to the shape and the size of the explosive chamber, and a preformed hole for installing a detonating cord is reserved at the top of the explosive during molding.
7. A method of performing underwater explosive cutting with the underwater explosive cutter assembly of any of claims 1 to 6, comprising the steps of: firstly, winding the waterproof inflatable rubber air bag on an object to be blasted; then, the explosive cutters are spliced to surround the object to be blasted and penetrate through a waterproof safety detonating cord, the plenum chamber covers of the explosive cutters are buckled on the waterproof inflatable rubber air bags, the waterproof inflatable rubber air bags are clamped into the plenum chambers of the explosive cutters, and the underwater explosive cutter assembly is assembled; the underwater explosion cutter assembly is sunk into a set explosion position along an object to be exploded by being suspended by a steel wire rope; inflating the waterproof inflatable rubber air bag until the inside of the inflatable chamber of the explosive cutter is filled; and finally, carrying out detonation operation.
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| CN201811054980.8A CN109211037B (en) | 2018-09-11 | 2018-09-11 | Underwater explosive cutter assembly and underwater explosive cutting method |
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| CN201811054980.8A CN109211037B (en) | 2018-09-11 | 2018-09-11 | Underwater explosive cutter assembly and underwater explosive cutting method |
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| CN109211037B true CN109211037B (en) | 2020-08-07 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| 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 |
| CN110004960A (en) * | 2019-05-11 | 2019-07-12 | 四川公路桥梁建设集团有限公司 | A kind of method for dismounting for the cutting of deep water Double-Wall Steel Boxed Cofferdam detonation cumulative penetration |
| CN110836621A (en) * | 2019-10-21 | 2020-02-25 | 四川航天川南火工技术有限公司 | Flexible energy-gathering cutting rope |
| CN112432567B (en) * | 2020-11-23 | 2023-05-05 | 浙江科技学院 | Energy-gathering electric blasting boulder method |
| CN113137894A (en) * | 2021-05-20 | 2021-07-20 | 中国人民解放军火箭军工程设计研究院 | Energy-containing composite shaped charge liner cutter structure |
| CN113188393A (en) * | 2021-05-20 | 2021-07-30 | 中国人民解放军火箭军工程设计研究院 | Prefabricated cutting body gathers can charge structure |
| CN113137893B (en) * | 2021-05-20 | 2022-08-02 | 中国人民解放军火箭军工程设计研究院 | Energy-containing special shaped charge cover cutter structure |
| CN113405420B (en) * | 2021-06-09 | 2022-09-27 | 南京君缘科爆工程技术有限公司 | Boundary control cutter and blasting device and method for nuclear power foundation pit energy-gathered cutting |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202239882U (en) * | 2011-07-06 | 2012-05-30 | 中国海洋石油总公司 | Underwater energy-accumulating blasting external cutting device |
| CN102494570B (en) * | 2011-12-06 | 2013-12-25 | 兰州大学 | Energy collecting blasting and smooth surface blasting combined control blasting method |
| US9822617B2 (en) * | 2012-09-19 | 2017-11-21 | Halliburton Energy Services, Inc. | Extended jet perforating device |
| CN203908426U (en) * | 2014-05-26 | 2014-10-29 | 葛洲坝易普力股份有限公司 | Circular jet cutter |
| CN104101273A (en) * | 2014-07-21 | 2014-10-15 | 中国船舶重工集团公司第七○二研究所 | Underwater explosion technology based novel explosion clearing device |
| CN104289755A (en) * | 2014-10-13 | 2015-01-21 | 中石化胜利油建工程有限公司 | Underwater steel pipe cutting device |
| CN204565434U (en) * | 2015-04-24 | 2015-08-19 | 河南省现代爆破技术有限公司 | A kind of blast jet cutter |
| CN105444623A (en) * | 2015-12-15 | 2016-03-30 | 中国石油天然气集团公司 | Energy-gathered cutting device for all-size gas blasting test of gas transmission steel pipe |
| CN107218862A (en) * | 2017-07-09 | 2017-09-29 | 贵州大学 | A kind of underwater demolition cumulative bullet and distribution method |
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