CN110260733B

CN110260733B - Hard rock one-time pit forming device and method for multidirectional energy-gathering hydraulic blasting

Info

Publication number: CN110260733B
Application number: CN201910602113.1A
Authority: CN
Inventors: 钟明寿; 谢兴博; 李兴华; 纪冲; 刘影; 杨贵丽; 赵杰
Original assignee: Army Engineering University of PLA
Current assignee: Army Engineering University of PLA
Priority date: 2019-07-05
Filing date: 2019-07-05
Publication date: 2023-06-20
Anticipated expiration: 2039-07-05
Also published as: CN110260733A

Abstract

The invention discloses a hard rock one-time pit forming device and method for multi-directional energy-gathering hydraulic blasting, wherein the blasting device comprises a detonation component, an upper explosive column unit, an explosion isolation tube, a lower explosive column unit and a throwing unit which are sequentially arranged from top to bottom; after the detonation component detonates, the upper charging unit is detonated, and then the lower charging unit is detonated after a period of time is delayed through the explosion isolation pipe, so that secondary rock blasting and broken stone cleaning are realized. Wherein the outer ring of the medicine tube shell is cylindrical, a plurality of V-shaped bulges are uniformly arranged on the inner ring, triangular columns are arranged between the adjacent V-shaped bulges, the upper end and the lower end of each triangular column are sealed, and the inside is filled with water. According to the invention, by researching the explosive-proof mechanism, the long-time separate detonation of the upper and lower charges in the hard hole is realized, and the primary detonation and the secondary throwing are formed, so that the pit meeting the requirement of the size parameter is better formed, and meanwhile, the blasting structure of the energy-gathering water pressure is more beneficial to the formation and the breaking of rock cracks and enlarges the forming size.

Description

Hard rock one-time pit forming device and method for multidirectional energy-gathering hydraulic blasting

Technical Field

The invention belongs to the technical field of blasting, and relates to a multidirectional water cutting energy gathering blasting device and method for performing one-step forming and stone breaking and throwing cleaning of special V-shaped pits on hard rock.

Background

In the fields of mining, construction and military applications, a special pit body with a V-shaped cross section is usually required to be cut out on hard rock, as shown in fig. 1, the V-shaped pit body is a V-shaped pit with a wide upper part and a narrow lower part, the opening d of the pit body is smaller than the depth h and has a certain inclination angle requirement, so-called a variant funnel is commonly used for cutting. Fig. 2 shows a conventional layered blasting forming method of V-shaped pits, firstly, a plurality of cut holes are drilled on the upper layer of rock, wherein the cut holes comprise a center hole and an edge hole, and the positions of the cut holes are shown as a hole position schematic diagram below fig. 2. And installing small equivalent explosive in each hole, removing slag after the first layer of explosion, repeating the steps, performing blasting slag removal of the second layer, and finally forming the pit body through multiple blasting operations. The method has the problems of large drilling quantity, long operation time and high explosive consumption, and is difficult to meet the requirement of rapid forming in military application occasions.

Disclosure of Invention

The invention aims to provide a blasting device and a blasting method for preparing special V-shaped pits in one-step forming of rock.

The specific technical scheme of the invention is as follows:

a hard rock one-time pit forming device for multidirectional energy-gathering hydraulic blasting is characterized in that: the blasting device comprises a detonation component, an upper explosive column unit, a detonation isolation pipe, a lower explosive column unit and a throwing unit which are sequentially arranged from top to bottom, the blasting device is placed in a prefabricated hole on the rock, after the detonation component detonates, the upper explosive column unit is detonated to blast the upper part of the rock for the first time, the lower explosive column unit is detonated to blast the lower part of the rock for the second time after a period of time is delayed by the detonation isolation pipe, and finally the throwing unit is detonated to perform throwing cleaning on broken stones in a pit body.

The upper explosive column unit and the lower explosive column unit are internally provided with an upper explosive tube and a lower explosive tube respectively, the upper explosive tube and the lower explosive tube are made of nonmetallic materials, the outer ring of the shell is cylindrical, the inner ring is uniformly provided with a plurality of V-shaped bulges, and the top angles of the V-shaped bulges are opposite to the central line of the explosive column; a triangular column body is arranged between the adjacent V-shaped bulges, the upper end and the lower end of the triangular column body are sealed, water is filled in the triangular column body, and the vertex angle of the triangular column body is opposite to the center line of the explosive column.

In the hard rock one-time pit forming device for multi-directional energy-gathering hydraulic blasting, the explosion isolation pipe comprises an upper connecting terminal and a lower connecting terminal which are movably connected through threads; the upper connecting terminal is of a flange structure, and an upper medicine tube of the upper medicine column unit is connected to the flange structure of the upper connecting terminal through threads; a first buffer cushion is arranged between the upper medicine tube and the flange structure; the first buffer cushion is of a hollow structure, and a second flexible detonating cord is arranged in the central through hole of the first buffer cushion; the outer side of the first buffer pad is provided with an annular groove and a straight groove which is communicated with the annular groove and the central through hole, and the annular groove and the straight groove are internally provided with a first flexible detonating cord; the first flexible detonating cord is contacted with the second flexible detonating cord;

the upper end of the lower connecting terminal is a sleeve, an inner sleeve and an outer sleeve are arranged outside the sleeve, a plurality of cascaded annular metal expansion pipes are arranged between the inner sleeve and the outer sleeve, the lower end of the lower connecting terminal is a flange, and the lower medicine pipes of the lower medicine column units are connected to the flange through threads; a lower layer of explosive column is arranged in the lower explosive tube, a second buffer cushion is arranged between the lower layer of explosive column in the lower explosive tube and the flange, the second buffer cushion is of a hollow structure, and a baffle delay detonator is arranged in the hollow part;

the throwing unit comprises a second metal expansion pipe and a bottom cover; the second metal expansion pipe is internally provided with a third buffer cushion, a metal bulging block and a throwing medicament from top to bottom in sequence, and the throwing medicament is blocked in the second metal expansion pipe by a bottom cover; the second metal expansion pipe is connected with the lower medicine pipe through threads, the third buffer pad is arranged between the metal expansion block and the lower medicine column, the third buffer pad and the metal expansion block are of hollow structures, a third flexible detonating cord is arranged in the middle of the third buffer pad, and the third flexible detonating cord stretches into the throwing medicine.

In the hard rock one-time pit forming device for multi-directional energy-gathering hydraulic blasting, a notch is formed in the inner ring of the annular metal expansion pipe, straight grooves are formed in the inner sleeve and the sleeve at positions corresponding to the notches, a fourth flexible detonating cord is arranged in the annular metal expansion pipe, coiled in the pipe of the annular metal expansion pipe and the straight grooves, and is in contact with the second flexible detonating cord; the annular metal expansion pipe is filled with explosive.

In the hard rock one-time pit forming device for multi-directional energy-gathering hydraulic blasting, a first metal expansion pipe is arranged in the tail end of the upper medicine pipe; the first metal expansion pipe is provided with internal threads and is connected with external threads on the flange structure of the upper connecting terminal.

In the hard rock one-time pit forming device for multi-directional energy-gathering hydraulic blasting, the inner wall of the second metal expansion pipe is of a cone structure with a large upper diameter and a small lower diameter, and the cone angle is 5-15 degrees.

In the hard rock one-time pit forming device for multidirectional energy-gathering hydraulic blasting, the detonation component comprises a detonation detonator, a plug and a sealing cover, wherein the detonation detonator is fixed on the plug through a detonator connector, and the sealing cover is arranged at the uppermost end of the detonation component.

In the hard rock one-time pit forming device for multi-directional energy-gathering hydraulic blasting, the upper explosive column in the upper explosive column unit is blocked inside the upper explosive tube by the plug of the detonation component.

In the hard rock one-time pit forming device for multi-directional energy-gathering hydraulic blasting, the upper medicine tube is made of PVC material; the inner sleeve and the outer sleeve are both made of silicon rubber.

In the hard rock one-time pit forming device for the multidirectional energy-gathering hydraulic blasting, the throwing agent is ammonium nitrate explosive, and the upper explosive column and the lower explosive column are TNT explosives.

The method for rapidly forming and throwing cleaning blasting the V-shaped pits on the rock is characterized by comprising the following steps of:

【1】 Drilling a straight hole with the diameter slightly larger than that of the medicine tube on the center of the designated area of the rock, and placing the assembled blasting device in the hole;

【2】 Igniting a detonating primer to cause the upper explosive column to explode, wherein the explosion shock wave forms an energy gathering effect along the V-shaped bulge of the explosive tube, and the explosion shock wave is combined with the water cutting shock effect of the triangular column body to carry out primary explosion on the rock;

performing first blasting on the rock;

【3】 The detonating primer initiates the upper explosive column to explode, so as to initiate the second flexible detonating cord to detonate;

【4】 After the second flexible detonating cord is detonated, the first flexible detonating cord is initiated, the first metal bulging tube is bulged, and the first buffer pad and the first metal bulging tube perform comprehensive action to buffer and separate the first explosion wave.

【5】 The second flexible detonating cord triggers the fourth flexible detonating cord and explosive filler in the cascaded annular metal expansion tube to explode, and the combined action of the inner sleeve, the outer sleeve, the upper connecting terminal, the lower connecting terminal, the second buffer pad and the annular metal expansion tube buffers and blocks the first explosion wave again;

【6】 The second flexible detonating cord triggers the baffle delay detonator, and after hundreds of milliseconds, the baffle delay detonator triggers the lower explosive column to detonate, the explosion shock wave forms an energy gathering effect along the V-shaped bulge of the explosive tube, and the second explosion is carried out on the rock by combining the water cutting impact effect of the triangular column, and meanwhile, the third flexible detonating cord is triggered to detonate;

【7】 And the third flexible detonating cord triggers the explosion of the throwing agent to throw and clean broken stone in the formed pit body.

The beneficial technical effects of this project are as follows:

1. according to the invention, through researching the hard rock blasting mechanism, the traditional rock drilling and kettle expanding blasting operation is simplified into one-time drilling, and then the modularized blasting device is directly placed into a prefabricated hole for one-time blasting pit body forming, so that the number of drilling holes is greatly reduced, meanwhile, the filling time is greatly shortened, and then the action of a throwing agent is combined, the slag is thrown by using the explosive energy, so that the manual slag removal workload is reduced, the forming efficiency is improved, and the requirement of rapid pit body forming in military application is met. Meanwhile, by adopting the measures of upper and lower charging and middle delay explosion isolation, the upper charging explodes to form a new free surface, thereby creating conditions for the lower small-dosage charging to be thrown into a pit again with high efficiency, limiting the breaking range of the next charging for the clamp production of the upper inverted cone-shaped explosion pit, realizing the control of the shape of the explosion pit, and finally forming the V-shaped pit meeting the size requirement by one-time ignition.

2. The grain shell adopts a structure of a energy-gathering cover and a triangular water cutter, a plurality of V-shaped bulges are arranged in the shell, and a plurality of triangular columns filled with water are arranged between the V-shaped bulges. Energy in explosion can be converged along the energy gathering hole to generate high-speed energy gathering jet flow to penetrate rock near a blast hole, so that a large number of cracks are generated on the hole wall in advance, gas generated by explosion can impact the cracks in a short time, the cracks are widened outwards continuously, the impact crushing of the rock is enhanced by the incompressibility of water, the water can be quickly vaporized under the action of high temperature and high pressure, the gas pressure of a blasting area is increased, the destructive effect of blasting gas is improved, the formation and crushing of rock cracks are facilitated, and the forming size is enlarged.

3. According to the invention, the explosion isolation pipe is arranged between the upper explosive unit and the lower explosive unit, so that the upper explosive unit is detonated and then the lower explosive unit is detonated after a period of time is delayed, and the secondary explosion of rock explosion is realized. When the upper explosive charge is exploded, the upper rock can be thrown off, a free surface is created for the lower explosive charge, and the blasting effect of the lower explosive charge is improved; simultaneously, the two-section type charging structure enables the upper charging to create a free surface for the lower charging, reduces the minimum resistance line of two charging blasting, and achieves one-time rapid forming of the V-shaped pit by using fewer charging.

4. In the implementation of the invention, detonation of the upper charge is converted into detonation energy of the lower charge, the lower charge is detonated after long delay, and energy control is one of the key problems of the project. The lower charge can be directly detonated due to the too small energy attenuation, and the lower charge cannot be detonated due to the too large energy attenuation, so that the explosion rejection is caused. The invention adopts methods of hard isolation, soft clipping, gradual reduction of impact energy and the like to block the explosion induction of the upper charge to the lower charge by designing the explosion isolation pipe structure, and realizes smooth propagation. Firstly, adopting polymer material polyurethane with clipping at the front end and the rear end of a connecting terminal for reducing the intensity of detonation wave; secondly, an annular groove structure with a built-in flexible detonating cord is added into the buffer pad at the front end, so that detonation energy is prevented from spreading downwards; finally, two annular metal expansion pipes with explosive fillers are arranged in the middle of the explosion isolation pipe, expand under the action of detonation waves, further fill blast holes, block downward movement of detonation products, block propagation of the detonation waves, and prevent the lower cartridge from being impacted, destroyed and detonated after the explosive column on the upper part explodes through the comprehensive explosion isolation function.

5. The explosion device and the detonation component, the connecting terminal and the upper and lower powder tubes are connected by screw threads, so that the on-site rapid assembly can be realized, meanwhile, in order to ensure the safety and reliability of products, in the process of transporting and storing the products, the explosive filled in each part is subjected to physical isolation measures with detonators, ignitors and the like with the detonating performance, even if the ignitors and the detonators are ignited and detonated accidentally, the explosive can not be initiated, and the components of the explosion device can be connected together rapidly by screw threads before use.

Drawings

FIG. 1 is a schematic diagram of an ideal V-shaped dimple configuration;

FIG. 2 is a schematic diagram of a blasting forming step of a V-shaped pit in the prior art;

FIG. 3 is a schematic diagram of the rapid prototyping blasting apparatus layout of the present invention;

FIG. 4 is a schematic view of the composition of the blasting apparatus of the present invention;

FIG. 5 is a schematic diagram of the detonation unit of the blasting apparatus of the present invention;

FIG. 6 is a schematic view of a slinging unit of the blasting device of the present invention;

FIG. 7 is a schematic view of a detonation isolating tube of the blasting apparatus of the present invention;

FIG. 8 is a cross-sectional view of the structure of FIG. 7 A-A in accordance with the present invention;

FIG. 9 is a cross-sectional view of the structure of FIG. 7B-B in accordance with the present invention;

FIG. 10 is a schematic view of the structure of the bulkhead delay detonator of the present invention;

FIG. 11 is a schematic illustration of a grain structure with a energy concentrating cap in accordance with a preferred embodiment of the present invention;

fig. 12 is a schematic illustration of a grain structure with a focus cap and water cutter in accordance with a preferred embodiment of the present invention.

The reference numerals are: 1-a bottom cover; 2-a second metal expanded tube; 3-slinging the medicament; 4-a metal bulging block; 5-a third cushion pad; 6-lower layer of grains; 7-lower medicine tube; 8, a partition board delay detonator; 9-an annular metal expansion tube; 10-an outer sleeve; 11-upper connection terminals; 12-a first flexible detonating cord; 13-a first cushion pad; 14-a second flexible detonating cord; 15-upper layer grain; 16-upper cartridge; 17-detonating primer; 18-plugs; 19-detonator joint; 20-sealing cover; 21-an initiating component; 22-an upper cartridge unit; 23-explosion isolation pipe; 24-a lower cartridge unit; 25-a slinging unit; 31-a second cushion pad; 33-a flange; 34-a sleeve; 35-inner sleeve; 36-lower connection terminals; 41-a first metal expanded tube; 43-a third flexible detonating cord; 44-a fourth flexible detonating cord; 45-explosive filling; 51—a central through hole; 52-an annular groove; 53-straight grooves; 54-a drug core; 55-the crust; 61-notch; 71-a housing; 72-explosive; 73-V-shaped protrusions; 74-triangular columns; 81-delay detonator; 82-connecting a fire tube; 83-a baffle igniter; 91-detonator leads; 92-prefabricating holes; 93-blasting device; 94-upper explosion pit; 95-lower explosion pit; 96-rock.

Detailed Description

The invention aims to obtain V-shaped pits with special dimensions by one-time blasting forming on hard rock, improve pit forming efficiency, avoid operation dangers caused by secondary explosive filling blasting construction, adopt the scheme that a blasting device for two-section explosive is filled after drilling holes on the rock, and delay between an upper explosive and a lower explosive is controlled, so that the upper explosive is filled to create a free surface for the lower explosive, the minimum resistance line of two explosive blasting is reduced, and a larger throwing effect is achieved by using fewer explosive, thereby realizing one-time blasting rapid forming of the pit.

As shown in fig. 3, the main technical route of the present invention is as follows: firstly, a handheld drilling machine is used for drilling a blast hole 92 in the vertical direction in a rock 96, then a blasting device 93 integrated with an up-and-down charging and delay explosion transfer unit, namely a cylindrical explosion pit device, is placed into the blast hole 92 according to the set height for detonation, and is blasted for a long distance through a detonator lead 91, so that the first layer of charging close to the ground surface breaks the rock, throws slag, an inverted conical upper explosion pit 94 is formed on the ground surface, and a new free surface is created for the next layer of charging. The next layer of charge with delayed detonation is blasted again at a certain distance below the upper blasting pit 94 to form a lower blasting pit 95, and the pit bottom rock is thrown to achieve the purpose of rapid blasting by one-time ignition to form a V-shaped pit.

Because the time-delay blasting is carried out in the rock prefabricated blast hole, detonation waves generated when the upper charge is blasted are downwards spread along with the hard hole wall, the lower charge is directly induced to be blasted when the detonation waves are propped against the lower charge, and in addition, in order to achieve the best effect, hundreds of milliseconds are required to be delayed after the upper charge is blasted, so that the detonation of the lower charge becomes the technical problem faced by the invention.

The traditional explosion mode also has a scheme of intermittent explosion in the upper and lower explosive column explosion. For example, an explosion-proof material is arranged between two explosion devices to perform explosion isolation, and the explosion-proof material generally only plays a role of blocking shock waves, so that the explosion delay between an upper charging unit and a lower charging unit can not be accurately controlled in explosion, and the requirement of providing a free surface for lower charging by upper charging is met; secondly, the invention needs to ensure the shape and the size of the V-shaped pit, and a blast hole with the diameter slightly larger than that of the blasting device is drilled on hard rock in advance, so that the whole two-stage blasting is carried out in a rock hole of a closed space, and the lower explosive is detonated by the detonation shock wave energy of the upper layer at the same time when in blasting, so that the effect of delay blasting cannot be achieved. Only by overcoming the problems, the rapid forming of the V-shaped pits on the hard rock can be finally realized.

As shown in fig. 4, the rock blasting apparatus of the present invention includes a detonation module 21, an upper grain unit 22, a shock insulator 23, a lower grain unit 24, and a slinging unit 25, which are sequentially disposed from top to bottom; after the detonation assembly 21 detonates, the upper explosive column unit 22 detonates the upper layer rock Dan Di once, and detonates the lower explosive column unit 24 to detonate the lower layer rock for the second time after a period of time is delayed by the explosion isolation tube 23, so that a special V-shaped pit meeting the size requirement is formed, and finally the detonation throwing unit 25 throws broken stone in the explosion pit.

As shown in fig. 4 and 5, the upper grain unit 22 includes an upper grain 16 and an upper grain 15 provided inside the upper grain 16, the upper grain 15 being blocked inside the upper grain 16 by a plug 18 of the initiation assembly 21; the upper tube 16 is made of PVC material and is primarily of reduced weight.

The detonation assembly 21 comprises a detonation cap 17, a plug 18 and a sealing cover 20, wherein the detonation cap 17 is used for detonating an upper explosive, and is connected with a detonating cord and a pulling method fire cap in series (not shown in the figure) and is stored separately at ordinary times for safety. The detonating primer 17 is fixed on the plug 18 through a primer connector 19, and the plug 18 is made of plastic and plays a role in plugging the upper explosive column and fixing the primer connector. The uppermost end of the initiation assembly 21 is provided with a flap 20. The flap 20 provides sealing, waterproofing, dust-proofing and protection. The detonator connector 19 ensures that the detonator is quickly plugged into place but cannot be pulled out, and the connection is convenient and quick.

Fig. 6 shows a schematic of the construction of the slinging unit 25 and the lower grain unit 24 of the blasting device of the present invention, the lower grain unit 24 comprising a lower grain tube 7 and an internally mounted lower grain 6. The lower tube 7 is made of cold drawn steel, and is used for preventing explosion isolation on one hand and resisting explosion generated when the upper tube is used for resisting the upper tube to generate impact on the lower tube. The slinging unit 25 comprises a second metal expanded tube 2 and a bottom cover 1; the bottom cover is made of plastic and is used for plugging the medicament in the lower medicament tube 7 and playing an anti-collision role.

The second metal expanded pipe 2 is internally provided with a third buffer cushion 5, a metal bulging block 4 and a throwing medicament 3 from top to bottom in sequence, and the throwing medicament 3 is blocked in the second metal expanded pipe 2 by a bottom cover 1; the second metal expanded tube 2 is connected with the lower medicine tube 7 through threads, a lower medicine column 6 is arranged in the lower medicine tube 7, a third buffer cushion 5 is arranged between the metal expanded block 4 and the lower medicine column 6, the third buffer cushion 5 and the metal expanded block 4 are hollow structures, a third flexible detonating cord 43 is arranged in the middle of the third buffer cushion 5 and the metal expanded block 4, and the third flexible detonating cord 43 stretches into the throwing medicine 3.

Wherein the second metal expansion tube 2 is a cone structure with a large upper diameter and a small lower diameter and is made of cold drawn steel, and the cone angle is preferably 5-15 degrees. The metal bulging block 4 moves downwards under the explosion extrusion effect of the lower explosive column 6 to radially expand the second metal bulging pipe 2 from inside to outside, so that the lower explosive tube 7 is prevented from downwards punching the top, and the effect of diffusing explosion waves to the periphery is achieved. The throwing agent 3 is ammonium nitrate explosive, the lower explosive column is TNT explosive, the detonation wave speed of the ammonium nitrate explosive is smaller than that of the TNT explosive during explosion, and the gas for throwing broken stone is easier to generate than TNT, so that the metal expanded tube 2 is presplit, and meanwhile, the ammonium nitrate explosive is used for blasting broken stone after blasting, so that broken stone cleaning in a pit is realized.

Fig. 7 to 10 show the structure of the explosion proof tube of the blasting apparatus of the present invention, the explosion proof tube 23 includes an upper connection terminal 11 and a lower connection terminal 36, and the connection terminals function to connect the upper and lower

explosive units

22 and 24 and function to transmit explosion, block and support, etc.

In fig. 7 and 8, the upper connection terminal 11 has a flange structure, and the upper medicine tube 16 of the upper medicine column unit 22 is coupled to the flange structure of the upper connection terminal 11 by screw threads; preferably, the interior of the trailing end of the upper tube 16 is provided with a first metal bulb 41; the first metal bulge tube 41 is provided with an internal thread, which is coupled with an external thread on the flange structure of the upper connection terminal 11.

A first cushion 13 is provided between the upper cartridge 16 and the flange structure. The first buffer pad 13 is of a hollow structure, and the second flexible detonating cord 14 passes through the central through hole 51; an annular groove 52 and a straight groove 53 which is communicated with the annular groove 52 and the central through hole 51 are arranged on the outer side of the first cushion pad 13, and the first flexible detonating cord 12 is arranged in the annular groove 52 and the straight groove 53. The middle part of the first flexible detonating cord 12 is wound in the annular groove 52, and both ends are arranged in the straight groove 53. The detonating cord of fig. 8 includes a core 54 and a sheath 55. The core 54 and sheath 55 of the first flexible detonating cord 12 are in secure contact with the outer sheath of the second flexible detonating cord 14, ensuring secure detonation. The second flexible detonating cord 14 mainly plays a role in explosion propagation, reliably detonates the first flexible detonating cord 12 and the rear partition delay detonator 8, and plugs the first metal expansion tube 41 to prevent the first metal expansion tube from moving downwards after explosion. The first metal expansion tube 41 is used for connecting the upper explosive unit 22 and the upper connecting terminal 11, and is internally provided with a buffer cushion, so that the detonation energy of the upper explosive unit 22 can be effectively attenuated and transmitted downwards. The buffer cushion is made of polyurethane, so that impact and damage caused by detonation of the upper explosive can be attenuated, the safety of the lower-layer medicament and other related components is protected, and the metal connecting terminal is prevented from losing the functions of blocking and supporting due to impact damage.

As shown in fig. 7 and 9, the upper end of the lower connecting terminal 36 is a sleeve 34, an inner sleeve 35 and an outer sleeve 10 are arranged outside the sleeve 34, the inner sleeve 35 and the outer sleeve 10 are made of silicone rubber, and an annular metal expansion tube 9 is arranged between the inner sleeve 35 and the outer sleeve 10. The inner sleeve 35 is of a hollow structure, the second flexible detonating cord 14 passes through the central through hole, a notch 61 is formed in the inner ring of the annular metal expansion tube 9, a straight groove 53 is formed in the positions, corresponding to the notch 61, of the inner sleeve 35 and the sleeve 34, the fourth flexible detonating cord 44 is arranged in the annular metal expansion tube 9, the fourth flexible detonating cord 44 is coiled in the tube of the annular metal expansion tube 9 and the straight groove 53, and the fourth flexible detonating cord 44 is reliably contacted with the second flexible detonating cord 14, so that reliable detonation is ensured. In addition, the inside of the annular metal expansion pipe 9 is filled with explosive filler 45, the explosive filler 45 is made of explosive, and can be detonated by the detonating cord 44, so that an acting force is generated on the annular metal expansion pipe 9 during explosion, the annular metal expansion pipe 9 is radially expanded, the annular metal expansion pipe 9 is embedded in the outer sleeve 10 made of silicon rubber, the outer diameter expansion of the sleeve after explosion is increased, the sleeve is tightly attached to the wall of a rock hole for blocking, and meanwhile, after the explosive filler 45 in the inner part is exploded, the explosive filler plays a role in blocking detonation waves which are transmitted after the upper explosive unit 22 is exploded, so that detonation energy of the upper explosive unit is prevented from being transmitted downwards, and the lower explosive pipe is caused to be subjected to transitional impact, damage and explosion or top impact. The purpose of the explosive filler 45 is to overcome the defect that the conventional detonating cord has small explosive power and is insufficient to ensure the effective expansion of the annular metal expansion tube 9, ensure that the explosion has enough expansion force and play a role in blocking the damage caused by downward transmission of the upper explosive.

The lower end of the lower connecting terminal 36 is a flange 33, and the lower medicine tube 7 of the lower medicine column unit 24 is connected to the flange 33 through threads; a second buffer cushion 31 is arranged between the lower explosive column 6 and the flange 33, the second buffer cushion 31 is of a hollow structure, and a baffle delay detonator 8 is arranged in the hollow part; the partition delay detonator 8 can block the energy of the detonating cord on one hand, and can play a role in starting up and down without influencing the delay time and detonation at the other end of the partition on the other hand.

In fig. 10, the partition board delay detonator 8 is composed of a delay detonator 81, a connecting fire tube 82 and a partition board igniter 83, and the partition board igniter 83 is screwed on the internal thread of the central through hole of the lower connecting terminal 36 through the external thread of the head part and is in butt joint with the second flexible detonating cord 14. The baffle igniter is used for igniting the delay powder of the baffle delay detonator 8 by rotating and burning detonation, so as to realize delayed detonation.

As shown in fig. 11, in order to further improve detonation power, the upper layer grain 15 and the lower layer grain 6 of the invention are changed from the common cylindrical charging in fig. 1 to a multidirectional shaped charging structure, in fig. 11, the shells 71 of the first medicine tube 16 and the second medicine tube 7 are made of lead-antimony alloy or steel and other metals, the explosive 72 is arranged inside the shells 71, the outer ring of the shells 71 is cylindrical, and a plurality of V-shaped protrusions 73 are uniformly arranged on the inner ring, and the number of the V-shaped protrusions is 4-8. The V-shaped projections 73 have a symmetrical triangular configuration in cross section with a vertex angle facing the centre line of the grain, the angle of the vertex angle being 30-60 °, preferably 45 °.

Explosion theory research shows that by adopting the blasting device with the multidirectional shaped charge structure, shock waves in explosion form energy gathering cavities at the positions of V-shaped protruding points, and the whole structure can form the multidirectional shaped charge blasting device. After the device is detonated, explosion energy is converged along the energy gathering hole to generate high-speed energy gathering jet flow to penetrate rock near a blast hole, so that a large number of cracks are generated on the hole wall in advance, and gas generated by explosion can impact the cracks in a short time, so that the cracks are widened outwards continuously, and the formation and crushing of rock cracks and the expansion of forming size are facilitated. The energy-gathering structure is not only suitable for soft rock, but also suitable for hard rock, and can greatly improve the blasting efficiency and reduce the dosage.

Fig. 12 shows a modification of fig. 11, except that the energy-gathering cover is made of a nonmetallic PVC material, and a plurality of triangular columns 74 are added between the V-shaped protrusions 73, the triangular columns 74 are also made of PVC material, the upper and lower ends are sealed, the inside is filled with water in advance, and the apex angle of the triangle is opposite to the center line of the grain. In addition to the cutting effect of the energy gathering cover, the incompressibility of water is utilized to strengthen impact crushing of rock, and the water can be quickly vaporized under the action of high temperature and high pressure, so that the gas pressure of a blasting area is increased, the destructive effect of blasting gas is improved, and the formation and crushing of rock cracks are facilitated, and the forming size is enlarged.

In practice, the second flexible detonating cord 14 is detonated after the explosion impact of the upper explosive column 15, the second flexible detonating cord 14 detonates the explosive at the input ends of the first flexible detonating cord 12, the fourth flexible detonating cord 44 and the partition board igniter 83, and then the explosive is detonated by the explosive of the connecting fire tube 82 to detonate the delay detonator 81, and after the time is delayed for a set time, the lower explosive column 6 is detonated. The baffle delay detonator 8 adopts the conventional prior art, the delay time can be customized by products to ensure the time length precision, and the delay time of the baffle delay detonator 8 in the project is about 500 milliseconds.

The whole blasting device of the invention is assembled and detonated as follows: before use, the detonation component 21 is mounted on the upper explosive tube 16, the upper explosive tube 16 is screwed with the upper connecting terminal 11, the lower explosive tube 7 of the lower explosive column unit 24 is screwed with the lower connecting terminal 36, the two ends of a blast hole are plugged, a detonator wire is taken out, the detonation wire is connected, the wire length is not less than 100 meters, the wire is pulled to a safe position, a special detonator is connected, and the detonation is performed under the condition that personnel and equipment are not needed in the detonation site.

The following describes the design of the blasting device and the principle of one shot blasting forming of V-shaped pits.

V-shaped pit requirement

As shown in FIG. 1, the V-shaped pit is of an inverted cone structure, the depth of the pit body is not less than 110 cm, the bottom width is 50 cm, and the caliber is not less than 65 cm. Basically is a cone with wide upper part and narrow lower part, and can be also called as a variable type blasting funnel; no concave-convex and unstable rock exists in the explosion pit after explosion, and meanwhile, the rock blocks in the pit are convenient for manual cleaning.

(II) parameter design

The parameters of the whole blasting device are as follows: the upper charge tube is made of PVC material, the size is 250mm multiplied by phi 70mm, the upper charge is 1.01 kg, and the weight of the component is less than 1.5kg; the explosion isolation tube is made of an expansion material, the size is less than 200mm multiplied by phi 70mm, and the weight is less than 1.2kg; the lower charge tube is made of A3 steel with better ductility, the size is less than 300mm multiplied by phi 70mm, the lower charge is 1.2kg, and the weight of the part is less than 2.0kg. The flameproof delay time of the upper and lower medicine pipes is not less than 500ms.

(III) one-step Forming principle of V-shaped pit

The explosion principle of the explosion device of the invention is as follows:

【1】 Firstly, drilling a prefabricated hole with the diameter slightly larger than that of a medicine tube on rock by adopting a hand-held drilling machine, and then placing the assembled blasting device in the hole;

【2】 The detonation detonator 17 is ignited to cause the upper explosive column 15 to explode, the explosion shock wave forms an energy gathering effect along the V-shaped bulge 73 of the explosive tube, and the water cutting impact effect of the triangular column 74 is combined to explode the rock for the first time;

【3】 The detonating primer 17 triggers the second flexible detonating cord 14 to detonate or triggers the second flexible detonating cord 14 to detonate after the upper explosive column 15 explodes;

【4】 After the second flexible detonating cord 14 is detonated, the first flexible detonating cord 12 is initiated to detonate, the first metal expansion tube 41 is expanded, and the first buffer pad 13 and the first metal expansion tube 41 perform combined action to buffer and block primary explosion waves;

【5】 The second flexible detonating cord 14 initiates the explosion of the fourth flexible detonating cord 44 and the explosion filler 45 in the cascaded annular metal expansion tube 9, and the primary explosion wave is buffered and blocked again under the combined action of the inner sleeve 35, the outer sleeve 10, the upper connecting terminal 11, the lower connecting terminal 36, the second buffer pad 31 and the annular metal expansion tube 9;

【6】 The second flexible detonating cord 14 triggers the baffle delay detonator 8, and after hundreds of milliseconds, the baffle delay detonator 8 triggers the lower explosive column 6 to detonate, the explosion shock wave forms an energy gathering effect along the V-shaped bulge 73 of the explosive tube, and the water cutting impact effect of the triangular column 74 is combined to perform secondary explosion on the rock;

【7】 Meanwhile, the third flexible detonating cord 43 is initiated by the partition delay detonator 8 or the third flexible detonating cord 43 is initiated by the explosion of the lower explosive column 6;

【8】 The third flexible detonating cord 43 triggers the throwing unit 25 to throw and clean broken stone in the formed pit body.

The invention can implement the one-time blasting forming of V-shaped pits with the depth of more than 1.1 m on hard rock, and can also be used for blasting forming of other special pits on the rock.

Claims

1. A hard rock one-time pit forming device for multidirectional energy-gathering hydraulic blasting is characterized in that: the blasting device (93) comprises a detonation component (21), an upper explosive column unit (22), a detonation isolation tube (23), a lower explosive column unit (24) and a throwing unit (25) which are sequentially arranged from top to bottom, the blasting device (93) is placed in a prefabricated hole (92) on a rock (96), after the detonation component (21) detonates, the upper explosive column unit (22) detonates the upper part of the rock (96) for the first time, and after a period of time is delayed by the detonation isolation tube (23), the lower explosive column unit (24) detonates the lower part of the rock (96) for the second time, and finally the throwing unit (25) detonates to clean broken stones in a pit body;

the upper explosive column unit (22) and the lower explosive column unit (24) are respectively provided with an upper explosive tube (16) and a lower explosive tube (7), the upper explosive tube (16) and the lower explosive tube (7) are made of nonmetallic materials, the outer ring of the shell (71) is cylindrical, the inner ring is uniformly provided with a plurality of V-shaped bulges (73), and the top angles of the V-shaped bulges (73) are right opposite to the central line of the explosive column; a triangular column body (74) is arranged between the adjacent V-shaped bulges (73), the upper end and the lower end of the triangular column body (74) are sealed, water is filled in the triangular column body, and the vertex angle of the triangular column body (74) is opposite to the central line of the medicine column;

the explosion isolation tube (23) comprises an upper connecting terminal (11) and a lower connecting terminal (36) which are movably connected through threads; the upper connecting terminal (11) is of a flange structure, and an upper medicine tube (16) of the upper medicine column unit (22) is connected to the flange structure of the upper connecting terminal (11) through threads; a first buffer pad (13) is arranged between the upper medicine tube (16) and the flange structure; the first buffer pad (13) is of a hollow structure, and a second flexible detonating cord (14) is arranged in the central through hole (51) of the first buffer pad; an annular groove (52) and a straight groove (53) which is communicated with the annular groove (52) and the central through hole (51) are formed in the outer side of the first buffer pad (13), and a first flexible detonating cord (12) is arranged in the annular groove (52) and the straight groove (53); the first flexible detonating cord (12) is contacted with the second flexible detonating cord (14);

the upper end of the lower connecting terminal (36) is provided with a sleeve (34), an inner sleeve (35) and an outer sleeve (10) are arranged outside the sleeve (34), a plurality of cascaded annular metal expansion pipes (9) are arranged between the inner sleeve (35) and the outer sleeve (10), the lower end of the lower connecting terminal (36) is provided with a flange (33), and a lower medicine pipe (7) of the lower medicine column unit (24) is connected to the flange (33) through threads; a second buffer pad (31) is arranged between the lower layer grain (6) and the flange (33) in the lower medicine tube (7), the second buffer pad (31) is of a hollow structure, and a partition delay detonator (8) is arranged in the hollow part;

the throwing unit (25) comprises a second metal expanded pipe (2) and a bottom cover (1); the second metal expanded pipe (2) is internally provided with a third buffer cushion (5), a metal bulging block (4) and a throwing medicament (3) from top to bottom in sequence, and the throwing medicament (3) is blocked inside the second metal expanded pipe (2) by a bottom cover (1); the second metal expansion pipe (2) is connected with the lower medicine pipe (7) through threads, a third buffer pad (5) is arranged between the metal expansion block (4) and the lower medicine column (6), the third buffer pad (5) and the metal expansion block (4) are hollow structures, a third flexible detonating cord (43) is arranged in the middle of the third buffer pad, and the third flexible detonating cord (43) stretches into the throwing medicine (3);

the detonation assembly (21) comprises a detonation detonator (17), a plug (18) and a sealing cover (20), wherein the detonation detonator (17) is fixed on the plug (18) through a detonator connector (19), and the sealing cover (20) is arranged at the uppermost end of the detonation assembly (21).

2. The multi-directional energy-gathering hydraulic blasting hard rock primary pit forming device according to claim 1, wherein: the inner ring of the annular metal expansion pipe (9) is provided with a notch (61), the positions of the inner sleeve (35) and the sleeve (34) corresponding to the notch (61) are provided with straight grooves (53), a fourth flexible detonating cord (44) is arranged in the annular metal expansion pipe (9), and the fourth flexible detonating cord (44) is coiled in the pipe of the annular metal expansion pipe (9) and the straight grooves (53) and is contacted with the second flexible detonating cord (14); the annular metal expansion pipe (9) is filled with explosive.

3. The multi-directional energy-gathering hydraulic blasting hard rock primary pit forming device according to claim 1, wherein: a first metal expansion tube (41) is arranged in the tail end of the upper medicine tube (16); the first metal expansion pipe (41) is provided with internal threads and is connected with external threads on the flange structure of the upper connecting terminal (11).

4. The multi-directional energy-gathering hydraulic blasting hard rock primary pit forming device according to claim 1, wherein: the inner wall of the second metal expansion tube (2) is of a cone structure with a large upper diameter and a small lower diameter, and the cone angle is 5-15 degrees.

5. The multi-directional energy-gathering hydraulic blasting hard rock primary pit forming device according to claim 1, wherein: the upper explosive column (15) in the upper explosive column unit (22) is blocked inside the upper explosive tube (16) by a plug (18) of the detonating assembly (21).

6. The multi-directional energy-gathering hydraulic blasting hard rock primary pit forming device according to claim 1, wherein: the upper medicine tube (16) is made of PVC material; the inner sleeve (35) and the outer sleeve (10) are both made of silicon rubber.

7. The multi-directional energy-gathering hydraulic blasting hard rock primary pit forming device according to claim 1, wherein: the throwing agent (3) is ammonium nitrate explosive, and the upper explosive column (15) and the lower explosive column (6) are TNT explosive.

8. A method of blasting hard rock primary pit forming device by using a multidirectional energy-gathering hydraulic blasting according to any one of claims 1 to 7, comprising the steps of:

【2】 The detonation detonator (17) is ignited to cause the upper explosive column (15) to explode, the explosion shock wave forms an energy gathering effect along the V-shaped bulge (73) of the explosive tube, and the water cutting impact effect of the triangular column (74) is combined to explode the rock for the first time;

【3】 The detonation detonator (17) causes the upper explosive column (15) to explode, thereby triggering the second flexible detonating cord (14) to detonate;

【4】 After the second flexible detonating cord (14) detonates, the first flexible detonating cord (12) is initiated, the first metal expanded tube (41) is expanded, the first buffer pad (13) and the first metal expanded tube (41) act comprehensively, and the first explosion wave is buffered and blocked;

【5】 The second flexible detonating cord (14) causes the fourth flexible detonating cord (44) and the explosion filler (45) in the cascaded annular metal expansion tube (9) to explode, and the first explosion wave is buffered and blocked again under the combined action of the inner sleeve (35), the outer sleeve (10), the upper connecting terminal (11), the lower connecting terminal (36), the second buffer pad (31) and the annular metal expansion tube (9);

【6】 The second flexible detonating cord (14) triggers the baffle delay detonator (8), after hundreds of milliseconds, the baffle delay detonator (8) triggers the lower explosive column (6) to detonate, the explosion shock wave forms an energy gathering effect along the V-shaped bulge (73) of the explosive tube, and the water cutting impact effect of the triangular column (74) is combined to perform secondary blasting on the rock, and meanwhile, the third flexible detonating cord (43) is triggered to detonate;

【7】 And the third flexible detonating cord (43) triggers the explosion of the throwing agent (3) to throw and clean broken stone in the formed pit.