Pre-splitting blasting device for surface mine

Abstract

The utility model provides a pre-splitting blasting device for a surface mine, which aims to effectively protect a non-excavation area and improve the pre-splitting blasting effect during pre-splitting blasting of the surface mine, and comprises an explosive charging pipe shell, an explosive discharging pipe shell and a pre-splitting blasting pipe shell, the explosive charging pipe shell is filled with explosives, and a friction part is arranged on the outer wall of the explosive charging pipe shell; the detonator is arranged in the charging tube shell; the buffer layer is arranged between the non-excavation area and the charging tube shell, the buffer layer comprises a gravel layer and a separation net layer, the gravel layer is arranged on the side, close to the non-excavation area, of the charging tube shell, and the separation net layer is arranged between the gravel layer and the non-excavation area; the plugging layer is arranged above the charging tube shell, the axial stability of the charging tube shell can be effectively improved through the arrangement of the friction part, the probability that blasting energy is not uniformly dispersed due to the position deviation of a blasting point caused by the displacement of the charging tube shell during blasting is reduced, and the blasting pre-splitting effect is improved; and the buffer layer can be supported and fixed in an auxiliary mode, and then a certain fixing effect on the charging tube shell is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of mine pre-splitting blasting, in particular to an open-pit mine pre-splitting blasting device. Background Art

[0002] In open-pit mining, pre-splitting blasting is a widely used technology that aims to separate and crush rock by precisely controlling the release of explosive energy. Traditional pre-splitting blasting methods usually involve directly loading explosives into drill holes and using detonators to detonate them to achieve the crushing effect.

[0003] In the prior art, the inventor has improved the pre-splitting blasting device and declared a pre-splitting blasting device with publication number CN212843221U, which mainly includes a PVC pipe, rock explosives filled inside the PVC pipe, and a detonating detonator pre-buried inside the rock explosive. One side of the PVC pipe is close to the excavation area, and a buffer layer is filled between the other side of the PVC pipe and the non-excavation area. A sealing layer is provided above the PVC pipe. Pre-splitting blasting is carried out through the device, and coupled charging is carried out through the PVC pipe, which improves the charging efficiency. Electronic detonators are used for detonation and ordinary rock explosives are used for blasting, which reduces blasting costs and is simple to operate. In addition, a buffer layer is provided between the PVC pipe and the non-excavation area to absorb the energy generated during blasting, reduce the hardness of the non-excavation area, and ensure the integrity of the non-excavation area.

[0004] However, during the construction of the above structure, the following problems were found:

[0005] 1) Using PVC pipes for coupled charging and uncoupled charging with the drilled hole can cause axial displacement of the PVC pipes due to the blasting effect, causing the detonator position to shift and the detonation point to no longer be in the ideal position, resulting in uneven distribution of blasting energy and ultimately abnormal crack morphology.

[0006] 2) Using a single layer of crushed stone as a buffer layer results in uneven energy attenuation, making it difficult to fully absorb the blast energy and resulting in unsatisfactory disturbance control effects in the trenchless area.

[0007] 3) A coupled charge structure is used between the excavation area and the PVC pipe. The shock wave generated by the explosion acts directly on the rock of the hole wall. However, due to the lack of effective guidance, the crack expansion is poorly controlled. If a conventional uncoupled charge structure is used, the amount of explosives used may increase, thereby increasing construction costs. Utility Model Content

[0008] The utility model provides an open-pit mine pre-splitting blasting device to effectively protect the non-excavation area during pre-splitting blasting in open-pit mines and improve the pre-splitting blasting effect. In order to achieve the above-mentioned purpose, the technical solution adopted is as follows:

[0009] An open-pit mine pre-splitting blasting device, characterized by comprising:

[0010] A charge shell is filled with explosives and has a friction portion on its outer wall;

[0011] Detonator, set in the charge tube shell;

[0012] A buffer layer is provided between the trenchless area and the charge shell, the buffer layer comprising a crushed stone layer and a mesh layer. The crushed stone layer is provided on the side of the charge shell close to the trenchless area, and the mesh layer is provided between the crushed stone layer and the trenchless area.

[0013] The sealing layer is arranged above the charge tube shell.

[0014] Furthermore, the friction portion is a friction stripe or protrusion provided on the outer wall of the charge tube shell.

[0015] Furthermore, the gravel layer includes a small-size gravel layer, a medium-size gravel layer and a large-size gravel layer which are arranged adjacent to each other in sequence. The small-size gravel layer is arranged on the side of the charging shell close to the non-excavation area, and the large-size gravel layer is arranged.

[0016] Furthermore, the particle size of the small-size crushed stone layer is 3-5 mm, the particle size of the medium-size crushed stone layer is 10-15 mm, and the particle size of the powerful diamond crushed stone layer is 20-30 mm.

[0017] Furthermore, the charge shell consists of an outer tube and an inner tube coaxially arranged inside the outer tube. The interior of the inner tube is a first cavity for filling explosives. A partition is fixedly connected between the outer tube and the inner tube. The partition divides the cavity between the outer tube and the inner tube into a second cavity and a third cavity. The second cavity is an air cavity and is close to the non-excavation area. The third cavity is a water cavity and is close to the excavation area. The friction part is arranged on the outer wall of the outer tube.

[0018] The utility model is beneficial in that:

[0019] 1. By setting a friction part on the outer wall of the charge shell, the friction between the charge shell and the hole wall and the buffer layer can be increased, the possibility of displacement of the charge shell can be reduced, thereby reducing the probability of the detonation point shifting during the blasting process and improving the crack morphology;

[0020] 2. The gravel layer in the buffer layer adopts a multi-level buffer structure, which can achieve graded and progressive energy attenuation, effectively reducing the damage to the non-excavation area. The setting of the isolation layer can not only help disperse the impact force of the explosion, but also play a role in supporting and fixing the gravel layer, and can indirectly fix the charge shell;

[0021] 3. The side of the charge shell close to the non-excavation area uses air medium to realize an uncoupled charge structure with the borehole. The characteristics of the uncoupled charge structure are used to reduce the disturbance to the non-excavation area. On the side close to the excavation area, a water medium cavity is set to form an uncoupled charge structure. The characteristics of the water medium can more effectively conduct the explosive energy. In addition, the pressure of the water medium blasting on the hole wall is relatively uniform, and the crack expansion is better controlled, thereby improving the accuracy of the pre-cracking effect. In addition, the uncoupled charge structure using water medium can effectively improve the crushing efficiency of the target rock mass and reduce construction costs compared with the air medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of the utility model

[0023] Figure 2 A top view of the charge shell structure

[0024] Figure 3 The main view of the charge shell

[0025] Among them: 1-charge shell, 101-inner tube, 102-outer tube, 103-partition, 104-first cavity, 105-second cavity, 106-third cavity, 107-friction part;

[0026] 2-gravel layer, 201-small-size gravel layer, 202-medium-size gravel layer, 203-large-size gravel layer;

[0027] 3-interval layer;

[0028] 4- sealing layer;

[0029] 5-detonator;

[0030] 6- rock explosives;

[0031] 7-foot line;

[0032] 8- Trenchless area;

[0033] 9- Excavation area. DETAILED DESCRIPTION

[0034] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0035] In the description of the utility model, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the viewing direction or position relationship, and are only for the convenience of describing the utility model, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0036] like Figure 1-Figure 3 The open-pit mine pre-splitting blasting device shown in FIG. 1 includes a charge shell 1, a buffer layer, and a blocking layer 4. A friction portion 107 is provided on the outer wall of the charge shell 1. In this embodiment, as shown in FIG. Figure 3 As shown, the friction portion 107 adopts friction stripes spirally distributed along the outer wall of the charge shell 1, and the buffer layer is composed of a crushed stone layer 2 and a mesh layer 3. The crushed stone layer 2 is arranged on the side of the charge shell 1 close to the non-excavation area 8, and the mesh layer 3 is arranged between the crushed stone layer 2 and the non-excavation area 8. The blocking layer 4 is arranged above the charge shell 1, and the upper ends of the crushed stone layer 2 and the mesh layer 3 are distributed higher than the charge shell 1.

[0037] By setting friction stripes on the outer wall of the charge tube shell 1, the friction between the charge tube shell 1 and the inner wall of the pre-crack hole and the buffer layer can be increased, reducing the probability that the detonation point is not in the ideal position due to displacement caused by blasting vibration and other reasons during the blasting process, improving the stability and positioning accuracy of the charge tube shell 1, and thus improving the effect of pre-crack blasting; and the setting of the buffer layer can absorb and disperse the impact force generated during blasting through the gravel layer 2, reducing the impact on the non-excavation area 8, and the isolation layer 3 connects the interface between the gravel layer 2 and the non-excavation area 8, which can not only assist in absorbing and dispersing the shock wave generated during the explosion, but also provide overall support for the buffer layer 3, preventing the gravel layer 2 from displacing or splashing during blasting, reducing the impact on the non-excavation area 8, and ensuring the effectiveness of the buffer layer. At the same time, the fixation of the position of the gravel layer 2 also indirectly realizes the positioning of the axial position of the charge tube shell 1.

[0038] Gravel layer 2 Figure 1As shown, it consists of a small-size crushed stone layer 201, a medium-size crushed stone layer 202 and a large-size crushed stone layer 203. The small-size crushed stone layer 201 is arranged on the side of the charging shell 1 close to the non-excavation area 8, and its particle size is 3-5 mm. The large-size crushed stone layer 203 is distributed close to the non-excavation area 8, and its particle size is 20-30 mm. The medium-size crushed stone layer 202 is arranged between the small-size crushed stone layer 201 and the large-size crushed stone layer 203, and its particle size is 10-15 mm. The small-size crushed stone layer 201 first contacts the explosion shock wave. The smaller particle size can increase the contact area with the shock wave, effectively absorbing and dispersing the explosion energy. The remaining energy is gradually attenuated through the medium-size crushed stone layer 202 and the large-size crushed stone layer 203. By setting up a multi-stage buffer crushed stone layer, the explosion shock wave can be effectively absorbed and dispersed, the damage to the non-excavation area 8 is reduced, and the pre-splitting blasting effect is improved.

[0039] Furthermore, it should be noted that the screen layer 3 in this embodiment is a metal screen with a pore size slightly smaller than that of the large-size crushed stone layer 203 , so as to reduce the impact of the crushed stones driven by the shock wave on the non-excavation area 8 during blasting.

[0040] In addition, in this embodiment, the charge shell 1 adopts a non-coupled charge structure with different media, specifically, Figure 1 and Figure 2 As shown, the charge shell 1 consists of an inner tube 101, an outer tube 102 and a partition 103, all of which are made of PVC. The outer tube 102 is coaxially arranged on the outside of the inner tube 101. The first cavity 104 in the inner tube 101 is used to hold rock explosives 6, and the detonator 5 is also arranged inside the first cavity 104. The leg line 7 of the detonator 5 passes upward through the sealing layer 4 and is led out to the outside. The partition 103 is symmetrically arranged between the cavity formed by the two, and the cavity between the inner tube 101 and the outer tube 102 is divided into a second cavity 105 and a third cavity 106 by the partition 103, wherein the second cavity 105 is close to the non-excavation area 8, and an air medium is arranged inside it. The third cavity 106 is arranged on the side close to the excavation area 9, and a water medium is arranged inside it.

[0041] The charge shell 1 uses an inner tube 101 for coupled charging, which improves the charging efficiency. Air is used as the medium on the side between the inner tube 101 and the outer tube 102 close to the non-excavation area 8, and the characteristics of uncoupled charging are used to reduce the disturbance to the surrounding rocks; water is used as the medium to form an uncoupled charge on the side close to the excavation area 9. Compared with coupled charging, the pressure exerted on the hole wall by water medium blasting is relatively uniform, and the crack expansion is better controlled, thereby improving the accuracy of the pre-cracking effect. Moreover, water medium has a stronger ability to transmit explosion pressure than air medium. The energy utilization rate of water medium explosives is higher, which can enhance the crushing effect on the target rock mass and improve the blasting efficiency. While achieving the same blasting effect, the charging density can be reduced, or in other words, under the same charging conditions, the blasting pre-cracking effect of water medium is better, thereby reducing construction costs.

[0042] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements can be made without departing from the principles of the present invention. These improvements should also be regarded as within the scope of protection of the present invention.

Claims

1. A pre-splitting blasting device for open-pit mines, characterized in that: include: A charge shell is filled with explosives and has a friction portion on its outer wall; Detonator, set in the charge tube shell; A buffer layer is provided between the trenchless area and the charge shell, the buffer layer comprising a crushed stone layer and a mesh layer. The crushed stone layer is provided on the side of the charge shell close to the trenchless area, and the mesh layer is provided between the crushed stone layer and the trenchless area. The sealing layer is arranged above the charge tube shell.

2. The open-pit mine pre-splitting blasting device according to claim 1, characterized in that: The friction portion is a friction stripe or protrusion arranged on the outer wall of the charge shell.

3. The open-pit mine pre-splitting blasting device according to claim 1, characterized in that: The crushed stone layer includes a small-size crushed stone layer, a medium-size crushed stone layer and a large-size crushed stone layer which are arranged adjacent to each other in sequence. The small-size crushed stone layer is arranged on the side of the charging shell close to the non-excavation area, and the large-size crushed stone layer is arranged.

4. The open-pit mine pre-splitting blasting device according to claim 3, characterized in that: The particle size of the small-size crushed stone layer is 3-5 mm, the particle size of the medium-size crushed stone layer is 10-15 mm, and the particle size of the large-size crushed stone layer is 20-30 mm.

5. The open-pit mine pre-splitting blasting device according to claim 1 or 2, characterized in that: The charge shell consists of an outer tube and an inner tube coaxially arranged inside the outer tube. The interior of the inner tube is a first cavity for filling explosives. A partition is fixedly connected between the outer tube and the inner tube. The partition divides the cavity between the outer tube and the inner tube into a second cavity and a third cavity. The second cavity is an air cavity and is close to the non-excavation area. The third cavity is a water cavity and is close to the excavation area. The friction part is arranged on the outer side wall of the outer tube.

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