Device and method for deep-hole pre-splitting blasting

Abstract

The present invention relates to a device for deep-hole pre-splitting blasting, comprising: a first row and a second row of initiating blast holes, each of which includes a plurality of first and second upward fan-shaped holes. Each first upward fan-shaped hole successively forms an emulsion explosive section, a stemming section, and an empty hole section from the inside to the outside. The emulsion explosive section is filled with digital electronic detonators and emulsion explosives; each second upward fan-shaped hole successively forms an emulsion explosive section, a stemming section, a pre-splitting section, and a stemming section. The emulsion explosive section is filled with digital electronic detonators and emulsion explosives. A pre-splitting device is installed in the pre-splitting section and emulsion explosive cartridges are loaded. The pre-splitting device is tied to a detonating cord, and the detonating cord connects the emulsion explosive cartridges and the digital electronic detonators; a detonator, which first detonates the pre-splitting section, then detonates the first row of initiating blast holes, and finally detonates the second row of initiating blast holes. In addition, the present invention also relates to a method for deep-hole pre-splitting blasting. The present invention can effectively block the damage of the surrounding rock of the roadway roof caused by the transfer of blasting energy during deep-hole blasting, achieving the effect of protecting the brow line and the roof.

Description

Technical Field

[0001] The present invention relates to the technical field of deep-hole blasting in mines, and more specifically, to a device and method for deep-hole presplitting blasting. Background Art

[0002] When driving the stoping roadway in an underground mine, affected by blasting vibration, the surrounding rock within a depth of two meters from the general surrounding rock is greatly affected by blasting vibration, forming a loosening circle of surrounding rock around the roadway. During subsequent blasting stoping, the surrounding rock mass within this thickness range is extremely vulnerable to damage. Deep-hole blasting is often used for ore drawing in underground mines. This blasting method has the advantages of a large amount of ore blasted in one blast and the charging construction being located under the roof, with construction safety and other advantages. However, this method has a relatively large amount of charge per section, resulting in a large vibration during blasting, which easily causes the surrounding rock within the loosening circle to be damaged by impact. And due to the large amount of charge and the downward direction of the blast holes, the energy during blasting impacts downward along the blast holes, often resulting in problems such as damage to the brow line and roof of the stoping roadway after blasting, affecting the safety of stoping operations. After the brow line is damaged, the ore will impact the roof into a slope, causing the phenomenon of buried holes. During the subsequent ore drawing process, due to the lack of the brow line, the overburden quickly mixes in, increasing the waste rock mixing rate and ore loss rate.

[0003] Based on this, a blasting device and method that can protect the integrity of the brow line, ensure the stability of the roof in the subsequent stoping area, and reduce ore loss and waste rock mixing are of great significance for solving the actual production problems in mines. Summary of the Invention

[0004] Aiming at the defects and deficiencies of the prior art and to solve the problems of damage to the brow line and roof after deep-hole blasting in underground mines, the present invention provides a device and method for deep-hole presplitting blasting to solve the damage to the brow line. The present invention charges the deep holes in sections, uses a presplitting device, and preferentially detonates the presplitting section in the second row of detonating blast holes. Before the first row of detonating blast holes is blasted, a presplitting crack is formed at the position of the loosening circle of the brow line surrounding rock, and then the first row of detonating blast holes and the second row of detonating blast holes are detonated, which can effectively block the stress propagation caused by the blasting energy during the blasting of the first row of detonating blast holes and reduce the damage of rock burst to the rear surrounding rock. The presplitting device in the present invention squeezes and fixes the explosive package on both sides of the blast hole through a spring structure, closely adhering to the wall surface of the blast hole. During blasting, the groove energy-gathering effect and interval charging of the presplitting device cause the explosive energy to propagate radially along the blast hole, achieving the presplitting blasting effect.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions:

[0006] According to one aspect of the present invention, there is provided a device for deep-hole presplitting blasting, comprising:

[0007] The first row of detonating blast holes, where the first row of detonating blast holes includes a plurality of first upward fan-shaped holes drilled in the stoping roadway. Each first upward fan-shaped hole successively forms an emulsion explosive section, a stemming section, and an empty hole section from the inside to the outside. The emulsion explosive section is loaded with digital electronic detonators and emulsion explosives;

[0008] The second row of detonating blast holes, where the second row of detonating blast holes includes a plurality of second upward fan-shaped holes drilled in the stoping roadway. Each second upward fan-shaped hole successively forms an emulsion explosive section, a stemming section, a pre-splitting section, and a stemming section from the inside to the outside. The emulsion explosive section is loaded with digital electronic detonators and emulsion explosives. A pre-splitting device is installed in the pre-splitting section and emulsion explosive cartridges are loaded. The pre-splitting device is tied to a detonating cord, the detonating cord is connected to the emulsion explosive cartridges and the detonating cord is connected to the digital electronic detonator;

[0009] A detonator, which is configured to first detonate the detonating cord through the digital electronic detonator, detonate the emulsion explosive cartridges by the detonating cord to detonate the pre-splitting device and thus detonate the pre-splitting section, then detonate the first row of detonating blast holes and finally detonate the second row of detonating blast holes.

[0010] In an embodiment of the present invention, the plurality of first upward fan-shaped holes adopt a staggered charge structure, and the plurality of second upward fan-shaped holes adopt a staggered charge structure.

[0011] In an embodiment of the present invention, the first row of detonating blast holes includes 11 first upward fan-shaped holes, and the second row of detonating blast holes includes 11 second upward fan-shaped holes.

[0012] In an embodiment of the present invention, the pre-splitting section is divided into at least three detonation batches.

[0013] In an embodiment of the present invention, the stemming sections of the first row of detonating blast holes and the two stemming sections of the second row of detonating blast holes are all stemmed with flame-retardant materials.

[0014] In an embodiment of the present invention, the emulsion explosive sections of the first row of detonating blast holes and the emulsion explosive sections of the second row of detonating blast holes both adopt full-coupling charging; the digital electronic detonators adopt bottom-hole detonation methods.

[0015] In an embodiment of the present invention, the pre-splitting device includes a pre-splitting guiding groove, a scale groove, a regulator, and a connecting groove. The pre-splitting device is composed of two relatively arranged pre-splitting guiding grooves. Each pre-splitting guiding groove has a groove side and a convex side. The groove side of the pre-splitting guiding groove abuts against the hole wall surface of the second upward fan-shaped hole. The scale grooves are spacedly arranged on the groove side of the pre-splitting guiding groove. The connecting grooves are staggeredly arranged at the head and tail of the pre-splitting guiding groove. The regulators are spacedly arranged between the convex sides of the two relatively arranged pre-splitting guiding grooves.

[0016] In one embodiment of the present invention, the regulator includes an adjusting pin, an adjusting column, and an adjusting spring. One side of the adjusting pin is connected to the protruding side of a presplitting guiding groove through the adjusting spring, the other side of the adjusting pin is connected to the adjusting column, and the adjusting column is connected to the protruding side of another presplitting guiding groove. And every two adjacent regulators are staggeredly arranged.

[0017] In one embodiment of the present invention, there are multiple emulsion explosive cartridges arranged at intervals, and each emulsion explosive cartridge can be cut open from the middle to form two split explosive cartridges, and the two split explosive cartridges are respectively loaded into the grooves on the groove sides of two presplitting guiding grooves.

[0018] In one embodiment of the present invention, the presplitting device is made of hard plastic.

[0019] According to another aspect of the present invention, there is provided a method for deep-hole presplitting blasting, comprising the following steps:

[0020] In the extraction roadway, drill multiple first upward fan-shaped holes. For each first upward fan-shaped hole, first load digital electronic detonators and emulsion explosives from the inside to the outside to form an emulsion explosive section, then plug it to form a stemming section, and the remaining empty holes form an empty hole section without loading explosives, constituting the first row of detonating blast holes;

[0021] In the extraction roadway, drill multiple second upward fan-shaped holes. For each second upward fan-shaped hole, first load digital electronic detonators and emulsion explosives from the inside to the outside to form an emulsion explosive section, then plug it to form a stemming section, then install the presplitting device and load emulsion explosive cartridges, bind the presplitting device with detonating cords and connect the detonating cords to the emulsion explosive cartridges, and connect the detonating cords to the digital electronic detonators to form a presplitting section, and finally plug it again to form a stemming section again, constituting the second row of detonating blast holes;

[0022] First, detonate the detonating cord through the digital electronic detonator, detonate the emulsion explosive cartridges by the detonating cord to detonate the presplitting device and thus detonate the presplitting section, then detonate the first row of detonating blast holes and finally detonate the second row of detonating blast holes.

[0023] In one embodiment of the present invention, the presplitting device includes presplitting guiding grooves, scale grooves, regulators, and connection grooves. The presplitting device is composed of two relatively arranged presplitting guiding grooves. Each presplitting guiding groove has a groove side and a protruding side. The groove side of the presplitting guiding groove abuts against the hole wall surface of the second upward fan-shaped hole. The scale grooves are arranged at intervals on the groove side of the presplitting guiding groove. The connection grooves are staggeredly arranged at the head and tail of the presplitting guiding groove. The regulators are arranged at intervals between the protruding sides of the two relatively arranged presplitting guiding grooves.

[0024] In one embodiment of the present invention, the regulator includes an adjusting pin, an adjusting column, and an adjusting spring. One side of the adjusting pin is connected to the protruding side of a presplitting guide groove through the adjusting spring, the other side of the adjusting pin is connected to the adjusting column, the adjusting column is connected to the protruding side of another presplitting guide groove, and every two adjacent regulators are staggered.

[0025] In one embodiment of the present invention, there are multiple emulsion explosive cartridges arranged at intervals, and each emulsion explosive cartridge can be split in the middle to form two split explosive cartridges, and the two split explosive cartridges are respectively loaded into the grooves on the concave sides of two presplitting guide grooves.

[0026] By adopting the above technical solutions, the present invention has the following advantages compared with the prior art:

[0027] By optimizing the initiation sequence and combining with the presplitting device, the present invention can effectively block the damage of the surrounding rock of the roadway roof caused by the transfer of blasting energy during deep-hole blasting, achieving the effect of protecting the brow line and the roof.

[0028] The present invention can not reduce the charge amount of the existing blast holes for ore fragmentation, can utilize the original empty hole section in the second row of initiation blast holes for presplitting design, and by using the effect of presplitting blasting, increase presplitting cracks in the surrounding rock to protect the stability of the surrounding rock of the roadway roof.

[0029] The structure of the present invention is simple, easy to manufacture, convenient for construction and installation, and can be mass-produced and practically used. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Shows a schematic structural diagram of the first row of initiation blast holes of a deep-hole presplitting blasting device provided by the present invention;

[0031] Figure 2 Shows a schematic structural diagram of the second row of initiation blast holes of a deep-hole presplitting blasting device provided by the present invention;

[0032] Figure 3 Shows a schematic diagram of the initiation sequence of a deep-hole presplitting blasting device provided by the present invention;

[0033] Figure 4 Shows Figure 2 a schematic structural diagram of the presplitting section;

[0034] Figure 5 Shows Figure 4 a schematic diagram of the charge structure of the presplitting section;

[0035] Figure 6 Shows a schematic structural diagram of the presplitting device adopted in the present invention.

[0036] LIST OF REFERENCE NUMERALS

[0037] 1. Extraction roadway, 2. First row of detonating blast holes, 3. Second row of detonating blast holes, 4. First upward fan-shaped hole, 5. Empty hole section, 6. Stemming section, 7. Emulsion explosive section, 8. Presplitting section, 9. Second upward fan-shaped hole, 10. Emulsion explosive cartridge, 11. Detonating cord, 12. Electronic detonator wire, 13. Digital electronic detonator, 14. Presplitting device, 15. Presplitting guide groove, 16. Scale groove, 17. Adjusting pin, 18. Adjusting column, 19. Adjusting spring, 20. Connecting groove, 21. Regulator. Detailed implementation manners

[0038] It should be understood that the embodiments of the present invention shown in the exemplary embodiments are merely illustrative. Although only a few embodiments of the present invention are described in detail, those skilled in the art can easily appreciate that various modifications are feasible without substantially departing from the teachings of the subject matter of the present invention. Accordingly, all such modifications should be included within the scope of the present invention. Without departing from the gist of the present invention, other substitutions, modifications, variations and deletions can be made to the design, operating conditions and parameters, etc. of the following exemplary embodiments.

[0039] As Figures 1-6 shown, the present invention provides a device for deep-hole presplitting blasting, including: the first row of detonating blast holes 2, the first row of detonating blast holes 2 includes a plurality of first upward fan-shaped holes 4 drilled in the extraction roadway 1, and each first upward fan-shaped hole 4 sequentially forms an emulsion explosive section 7, a stemming section 6, and an empty hole section 5 from inside to outside, and the emulsion explosive section 7 is loaded with digital electronic detonators 13 and emulsion explosives; the second row of detonating blast holes 3, the second row of detonating blast holes 3 includes a plurality of second upward fan-shaped holes 9 drilled in the extraction roadway 1, and each second upward fan-shaped hole 9 sequentially forms an emulsion explosive section 7, a stemming section 6, a presplitting section 8, and a stemming section 6 from inside to outside, the emulsion explosive section 7 is loaded with digital electronic detonators and emulsion explosives, the presplitting section 8 is provided with a presplitting device 14 and loaded with emulsion explosive cartridges 10, the presplitting device 14 is tied to the detonating cord 11, the detonating cord 11 is connected to the emulsion explosive cartridge 10 and the detonating cord 11 is connected to the digital electronic detonator 13; a detonator (not shown), the detonator is configured to first detonate the detonating cord 11 through the digital electronic detonator 13, detonate the emulsion explosive cartridge 10 by the detonating cord 11 to detonate the presplitting device 14 and then detonate the presplitting section 8, then detonate the first row of detonating blast holes 2 and finally detonate the second row of detonating blast holes 3.

[0040] Through the above technical solutions of the present invention, the present invention can effectively block the damage of the surrounding rock of the roadway roof caused by the transfer of blasting energy during deep-hole blasting, achieving the effect of protecting the brow line and the roof.

[0041] In the above device, as Figures 1-2 shown, a plurality of first upward fan-shaped holes 4 adopt a staggered charging structure, and a plurality of second upward fan-shaped holes 9 adopt a staggered charging structure.

[0042] In the above device, as Figures 1-2 shown, preferably, the first row of initiating blast holes includes 11 first upward fan-shaped holes, and the second row of initiating blast holes includes 11 second upward fan-shaped holes.

[0043] In the above device, as Figure 3 shown, the pre-splitting section is divided into at least three initiating batches.

[0044] In the above device, as Figures 1-2 shown, the stemming sections 6 of the first row of initiating blast holes 2 and the two stemming sections 6 of the second row of initiating blast holes 3 are all stemmed with flame-retardant materials.

[0045] In the above device, as Figures 1-2 shown, the emulsion explosive sections 7 of the first row of initiating blast holes 2 and the emulsion explosive sections 7 of the second row of initiating blast holes 3 are all charged with full-coupling. As Figure 5 shown, the digital electronic detonator 13 adopts the bottom-hole initiation method.

[0046] In the above device, as Figure 6 shown, the pre-splitting device 14 includes a pre-splitting guide groove 15, a scale groove 16, a regulator 21 and a connecting groove 20. The pre-splitting device 14 is composed of two relatively arranged pre-splitting guide grooves 15. Each pre-splitting guide groove 15 has a groove side and a convex side. The groove side of the pre-splitting guide groove 15 abuts against the hole wall surface of the second upward fan-shaped hole 9. The scale grooves 16 are arranged at intervals on the groove side of the pre-splitting guide groove 15. The connecting grooves 20 are arranged alternately at the head and tail of the pre-splitting guide groove 15. The regulators 21 are arranged at intervals between the convex sides of the two relatively arranged pre-splitting guide grooves 15.

[0047] In the above device, as Figure 6 shown, the regulator 21 includes an adjusting pin 17, an adjusting column 18 and an adjusting spring 19. One side of the adjusting pin 17 is connected to the convex side of a pre-splitting guide groove 15 through the adjusting spring 19. The other side of the adjusting pin 17 is connected to the adjusting column 18. The adjusting column 18 is connected to the convex side of another pre-splitting guide groove 15, and every two adjacent regulators 21 are arranged alternately.

[0048] In the above device, as Figures 4-5 shown, there are multiple emulsion explosive cartridges 10 arranged at intervals, and each emulsion explosive cartridge 10 can be cut open from the middle to form two split explosive cartridges, and the two split explosive cartridges are respectively loaded into the grooves on the groove sides of the two pre-splitting guide grooves 15.

[0049] In the above device, the pre-splitting device 14 is made of hard plastic.

[0050] In addition, the present invention also provides a method for deep-hole pre-splitting blasting, as Figures 1-6 shown, the method includes the following steps:

[0051] In the extraction roadway 1, multiple first upward fan-shaped holes 4 are drilled. For each first upward fan-shaped hole 4, digital electronic detonators 13 and emulsion explosives are first loaded from the inside to the outside to form an emulsion explosive section 7, and then blocked to form a stemming section 6. The remaining empty holes form an empty hole section 5 without explosives, constituting the first row of initiating blast holes 2;

[0052] In the extraction roadway 1, multiple second upward fan-shaped holes 9 are drilled. For each second upward fan-shaped hole 9, digital electronic detonators 13 and emulsion explosives are first loaded from the inside to the outside to form an emulsion explosive section 7, and then blocked to form a stemming section 6. Then, a pre-splitting device 14 is installed and emulsion explosive cartridges 10 are loaded. The pre-splitting device 14 is tied to the detonating cord 11 and the detonating cord 11 is connected to the emulsion explosive cartridge 10, and the detonating cord 11 is connected to the digital electronic detonator 13 to form a pre-splitting section 8. Finally, it is blocked again to form a stemming section 6 again, constituting the second row of initiating blast holes 3;

[0053] The detonating cord 11 is first detonated by the digital electronic detonator 13, and the emulsion explosive cartridge 10 is detonated by the detonating cord 11 to detonate the pre-splitting device 14 and detonate the pre-splitting section 8, and then the first row of initiating blast holes 2 is detonated and finally the second row of initiating blast holes 3 is detonated.

[0054] The above technical solutions of the present invention will be described in detail below through specific embodiments.

[0055] As Figures 1-6 shown, in this embodiment, the device for deep-hole pre-splitting blasting provided by the present invention includes an extraction roadway 1, a first row of initiating blast holes 2, a second row of initiating blast holes 3, first upward fan-shaped holes 4, an empty hole section 5, a stemming section 6, an emulsion explosive section 7, a pre-splitting section 8, second upward fan-shaped holes 9, emulsion explosive cartridges 10, detonating cords 11, electronic detonator wires 12, digital electronic detonators 13, and a pre-splitting device 14. The pre-splitting device 14 is composed of a pre-splitting guide groove 15, a scale groove 16, a regulator 21 (which includes an adjusting pin 17, an adjusting column 18, and an adjusting spring 19), and a connecting groove 20.

[0056] In the embodiment of the present invention, two rows of blast holes, namely the first row of initiating blast holes 2 and the second row of initiating blast holes 3, are detonated at one time in the extraction roadway 1. Both the first row of initiating blast holes 2 and the second row of initiating blast holes 3 are composed of 11 blast holes. The first row of initiating blast holes 2 is the first row of blast holes close to the extraction face, and the second row of initiating blast holes 3 is the second row of blast holes in the direction of the roadway mouth of the first row of initiating blast holes 2. In this embodiment, the diameter of the blast hole is 76 mm, the emulsion explosive cartridge is Φ32 mm, the length is 200 mm, the weight is 200 g, and the emulsion explosives are all 2# rock emulsion explosives.

[0057] In the embodiment of the present invention, the empty hole section in the second row of initiating blast holes 3 is mainly designed as a pre-splitting section. Combining with the pre-splitting device, it is initiated prior to the first row of initiating blast holes 2 to form a pre-splitting crack, blocking the stress wave generated by the blasting of the first row of initiating blast holes 2. As Figures 1-6 shown, the specific implementation steps are as follows:

[0058] (1) In the stoping roadway 1, the first upward fan-shaped hole 4 and the second upward fan-shaped hole 9 are respectively drilled. First, digital electronic detonators 13 and emulsion explosives are loaded into the first upward fan-shaped hole 4 to form an emulsion explosive section 7. Subsequently, the blast hole is blocked with stemming to form a stemming section 6, and the remaining empty hole forms an empty hole section 5 without loading explosives. After the work is completed, the first row of initiating blast holes 2 is formed. The specific structure is as Figure 1 shown.

[0059] (2) Digital electronic detonators 13 and emulsion explosives are loaded into the second upward fan-shaped hole 9 to form an emulsion explosive section 7. Subsequently, the blast hole is blocked with stemming to form a stemming section 6. The emulsion explosive cartridge 10 is split in the middle to form two split explosive cartridges (each 100 g and 200 mm long). The detonating cord 11 and the pre-splitting device 14 are respectively tied together with adhesive tape at the designed spacing. The spacing of the emulsion explosive cartridges 10 varies from 500 mm to 600 mm. Multiple pre-splitting devices 14 are connected together with adhesive tape through the connecting grooves 20 on the device to form an uncoupled charge structure required for pre-splitting blasting, forming a pre-splitting section 8. Then, the blast hole is blocked with stemming again to form a stemming section 6. After the work is completed, the second row of initiating blast holes 3 is formed. The specific structure is as Figure 2 and 4 shown.

[0060] (3) The emulsion explosive sections 7 of the above two rows of initiating blast holes are directly initiated by the digital electronic detonators 13. For the pre-splitting section 8, the digital electronic detonator 13 first initiates the detonating cord 11, and then the detonating cord 11 initiates the emulsion explosive cartridge 10. Finally, the wires 12 of the detonated electronic detonators are unified and assembled, and are initiated uniformly from the initiation point.

[0061] (4) During initiation, according to the detonator delay as Figure 3 shown, the pre-splitting section 8 is initiated first, so as to form a pre-splitting crack between the first row of initiating blast holes 2 and the roadway surrounding rock, blocking the stress propagation. Then, the first row of initiating blast holes 2 is initiated, and finally the second row of initiating blast holes 3.

[0062] In the above specific implementation steps, preferably, as Figures 1-2 shown, the first upward fan-shaped hole 4 adopts a staggered charge structure, and the charge lengths of the blast holes at the same positions (such as blast holes 6-1# and 6-2#, blast holes 5-1# and 5-2#) as those of the second upward fan-shaped hole 9 also form a stagger.

[0063] In the above specific implementation steps, preferably, as Figure 3In the shown initiation sequence diagram, the presplitting section 8 can be divided into 3 initiation batches, with the sequence being (YL-5, YL-6, YL-7) — (YL-1, YL-2, YL-3, YL-4) — (YL-8, YL-9, YL-10, YL-11), and the detonator delay times for separate initiations are 10 ms, 15 ms, and 20 ms respectively.

[0064] In the above specific implementation steps, preferably, as Figure 3 shown in the initiation sequence diagram. After the presplitting section 8 completes blasting, the first row of initiation blast holes 2 is initiated, with the initiation sequence being (6-1#) — (5-1#) — (7-1#) …… — (1-1#) — (11-1#). After the first row of initiation blast holes 2 completes blasting, the second row of initiation blast holes 3 is initiated in sequence, with the initiation sequence being (6-2#) — (5-2#) — (7-2#) …… — (1-2#) — (11-2#). The millisecond interval between every two adjacent holes is 25 ms.

[0065] In the above specific implementation steps, preferably, the stemming section 6 is stemmed with a flame-retardant material, and the effective stemming length should be ≥500 mm.

[0066] In the above specific implementation steps, as Figure 1 shown, preferably, the first upward fan-shaped hole 4 is divided into an emulsion explosive section 7, a stemming section 6, and an empty hole section 5. The length of the empty hole section 5 is 2 - 6 m, at least not less than 1 / 10 of the total length of the first upward fan-shaped hole 4 and at most not exceeding 1 / 2 of the total length of the first upward fan-shaped hole 4.

[0067] In the above specific implementation steps, preferably, the emulsion explosive section 7 uses full-coupling charging, and the digital electronic detonator 13 uses the bottom-hole initiation method.

[0068] In the above specific implementation steps, as Figure 2 shown, preferably, the presplitting section 8 uses an uncoupled charging structure. Each emulsion explosive cartridge 10 in each section is split into two halves, and each half is connected in series with an emulsion explosive cartridge using a detonating cord 11. The detonating cord 11 is initiated at the hole mouth using a digital electronic detonator 13.

[0069] In the above specific implementation steps, as Figure 2 shown, preferably, the first emulsion explosive cartridge in the emulsion explosive cartridges 10 of the presplitting section 8 should be kept at a distance greater than 100 mm from the stemming section 6.

[0070] In the above specific implementation steps, as Figure 2As shown, preferably, when the hole section length of the pre-splitting section 8 is greater than 5m, the spacing between the end emulsion explosive cartridges 10 is less than 500mm. After charging to exceed the stemming section 6 of the adjacent blast holes, the spacing increases to 600mm, and the maximum spacing shall not be greater than 800mm. When the hole section length of the pre-splitting section 8 is less than 5m, the spacing of the charge with full interval is less than 500mm, and the minimum spacing shall not be less than 350mm.

[0071] In the above specific implementation steps, preferably, as Figure 5 shown in the structural schematic diagram of the pre-splitting section, the pre-splitting device 14 should be in the same plane as the other blast holes of the second upward fan-shaped hole 9. The pre-splitting guiding groove 15 is closely attached to the hole wall surface to ensure that the blasting energy on both adjacent sides converges on one plane during blasting, so as to form a pre-splitting crack.

[0072] In the above specific implementation steps, preferably, as Figure 6 shown in the pre-splitting device, the pre-splitting device is composed of two pre-splitting guiding grooves 15, with a single length of 500mm, a guiding groove diameter of 35mm, and a scale groove 16 is arranged at an interval of 50mm, with a groove depth of 3mm; at the head and tail of the pre-splitting guiding groove 15, connecting grooves 20 with a length of 25mm are arranged in a staggered manner as the connecting ends of multiple pre-splitting guiding grooves 15, and adhesive tape is used for binding during connection.

[0073] In the above specific implementation steps, preferably, as Figure 6 shown, a regulator 21 is arranged at a spacing of 100mm on the convex side (ridge part) of the pre-splitting guiding groove 15: it is composed of an adjusting pin 17, an adjusting column 18 and an adjusting spring 19. The inner diameter of the adjusting pin 17 is 10mm and the length is not greater than 100mm. The outer diameter of the adjusting column 18 is 9.5mm and the length is not greater than 100mm; during installation, a 35mm long adjusting spring 19 is installed in the adjusting pin 17, with a spring diameter of 9mm and a spring Hooke's coefficient greater than 200N / m. Two pre-splitting guiding grooves 15 are combined into an independent pre-splitting device 14. A pre-splitting section 8 can be composed of multiple pre-splitting devices 14 connected together, and multiple pre-splitting devices 14 are connected through the connecting grooves 20 arranged in a staggered manner at the head and tail.

[0074] In the above specific implementation steps, preferably, according to the hole diameter situation, the adjusting pin 17 and the adjusting column 18 can be shortened. In the 76mm blast hole of this example, the lengths of the adjusting pin 17 and the adjusting column 18 can be reduced to 30mm.

[0075] In the above specific implementation steps, preferably, the material of the pre-splitting device 14 is made of hard plastic, and the shell thickness shall not be less than 2mm to ensure strength.

[0076] It can be seen that through the above technical solutions of the present invention, the present invention can effectively block the damage of the surrounding rock of the roadway roof caused by the transmission of blasting energy during deep-hole blasting, achieving the effect of protecting the brow line and the roof. The present invention can not reduce the amount of explosive charged for ore fragmentation in the existing blast holes, can utilize the original empty hole section in the second row of detonating blast holes for presplitting design, and by using the effect of presplitting blasting, presplitting cracks can be added in the surrounding rock to protect the stability of the surrounding rock of the roadway roof.

[0077] The above are only the preferred embodiments of the present invention and are not used to limit the scope of implementation of the present invention; any modification or equivalent replacement made to the present invention without departing from the spirit and scope of the present invention shall be covered by the protection scope of the claims of the present invention.

Claims

1. A device for deep-hole pre-splitting blasting, characterized in that, Including: The first row of detonating blast holes, the first row of detonating blast holes includes a plurality of first upward fan-shaped holes drilled in the stoping roadway, each of the first upward fan-shaped holes sequentially forms an emulsion explosive section, a stemming section, and an empty hole section from the inside to the outside, the emulsion explosive section is filled with digital electronic detonators and emulsion explosives, wherein, a plurality of the first upward fan-shaped holes adopt a staggered charging structure; The second row of detonating blast holes, the second row of detonating blast holes includes a plurality of second upward fan-shaped holes drilled in the stoping roadway, each of the second upward fan-shaped holes sequentially forms an emulsion explosive section, a stemming section, a pre-splitting section, and a stemming section from the inside to the outside, the emulsion explosive section is filled with digital electronic detonators and emulsion explosives, a pre-splitting device is installed in the pre-splitting section and filled with emulsion explosive cartridges, the pre-splitting device is tied with a detonating cord, the detonating cord is connected to the emulsion explosive cartridge and the detonating cord is connected to the digital electronic detonator, wherein, a plurality of the second upward fan-shaped holes adopt a staggered charging structure; A detonator, the detonator is configured to first detonate the detonating cord through the digital electronic detonator, detonate the emulsion explosive cartridge by the detonating cord to detonate the pre-splitting device to detonate the pre-splitting section, then detonate the first row of detonating blast holes and finally detonate the second row of detonating blast holes; Wherein, the pre-splitting device includes a pre-splitting guiding groove, a scale groove, a regulator, and a connecting groove, the pre-splitting device is composed of two oppositely arranged pre-splitting guiding grooves, each pre-splitting guiding groove has a groove side and a convex side, the groove side of the pre-splitting guiding groove abuts against the hole wall surface of the second upward fan-shaped hole, the scale groove is spacedly arranged on the groove side of the pre-splitting guiding groove, the connecting groove is staggeredly arranged at the head and tail of the pre-splitting guiding groove, and the regulator is spacedly arranged between the convex sides of two oppositely arranged pre-splitting guiding grooves.

2. The device for deep-hole pre-splitting blasting according to claim 1, characterized in that, The pre-splitting section is divided into at least three detonation batches.

3. The device for deep-hole pre-splitting blasting according to claim 1, characterized in that, The regulator includes an adjusting pin, an adjusting column, and an adjusting spring, one side of the adjusting pin is connected to the convex side of one pre-splitting guiding groove through the adjusting spring, the other side of the adjusting pin is connected to the adjusting column, the adjusting column is connected to the convex side of the other pre-splitting guiding groove, and every two adjacent regulators are staggeredly arranged.

4. The device for deep-hole pre-splitting blasting according to claim 3, characterized in that, There are a plurality of the emulsion explosive cartridges and they are spacedly arranged, and each emulsion explosive cartridge can be cut in half from the middle to form two split explosive cartridges, and the two split explosive cartridges are respectively loaded into the grooves on the groove sides of the two pre-splitting guiding grooves.

5. A method for deep-hole pre-splitting blasting, characterized in that, Including the following steps: Drill a plurality of first upward fan-shaped holes in the stoping roadway, first load digital electronic detonators and emulsion explosives into each first upward fan-shaped hole from the inside to the outside to form an emulsion explosive section, then plug it to form a stemming section, and the remaining empty holes form an empty hole section and are not filled with explosives, constituting the first row of detonating blast holes; In the extraction roadway, drill holes to form a plurality of second upward fan-shaped holes. For each second upward fan-shaped hole, first load digital electronic detonators and emulsion explosives from the inside to the outside to form an emulsion explosive section, then plug it to form a stemming section. Next, install a pre-splitting device and load emulsion explosive cartridges, tie the pre-splitting device to a detonating cord and connect the detonating cord to the emulsion explosive cartridges, and connect the detonating cord to the digital electronic detonator to form a pre-splitting section. Finally, plug it again to form a stemming section again, constituting the second row of initiating blast holes; First, the digital electronic detonator detonates the detonating cord, the detonating cord detonates the emulsion explosive cartridges to detonate the pre-splitting device to detonate the pre-splitting section, then detonate the first row of initiating blast holes and finally detonate the second row of initiating blast holes; Wherein, the pre-splitting device includes a pre-splitting guiding groove, a scale groove, a regulator and a connecting groove. The pre-splitting device is composed of two oppositely arranged pre-splitting guiding grooves. Each pre-splitting guiding groove has a groove side and a convex side. The groove side of the pre-splitting guiding groove abuts against the hole wall surface of the second upward fan-shaped hole. The scale groove is arranged at intervals on the groove side of the pre-splitting guiding groove. The connecting grooves are arranged alternately at the head and tail of the pre-splitting guiding groove. The regulator is arranged at intervals between the convex sides of the two oppositely arranged pre-splitting guiding grooves.

6. The method for deep-hole pre-splitting blasting according to claim 5, characterized in that, The regulator includes an adjusting pin, an adjusting column and an adjusting spring. One side of the adjusting pin is connected to the convex side of one pre-splitting guiding groove through the adjusting spring. The other side of the adjusting pin is connected to the adjusting column, and the adjusting column is connected to the convex side of the other pre-splitting guiding groove, and every two adjacent regulators are arranged alternately.

7. The method of deep-hole pre-splitting blasting according to claim 6, characterized in that, There are a plurality of emulsion explosive cartridges arranged at intervals, and each emulsion explosive cartridge can be cut in half from the middle to form two half explosive cartridges, and the two half explosive cartridges are respectively loaded into the grooves on the groove sides of the two pre-splitting guiding grooves.

Images