A method for preventing the return of powder in the hole during the charging of a powder explosive

Abstract

The present application relates to a method for preventing powder explosives from returning when charging in a hole, which comprises the following steps: firstly, cutting a PVC pipe as a charging end; then, installing a circle of hard plastic blades which can rotate up and down on the inner and outer walls of the PVC pipe at the same position in the axial direction, and connecting the inner and outer blades at the same position in the radial direction by an arc metal rod which penetrates the wall of the PVC pipe; finally, connecting the PVC pipe with the hard plastic blades to the powder explosives delivery pipe, inserting into the bottom of the rock drilling hole, and withdrawing the charging pipe while injecting the powder explosives into the rock drilling hole. During the above charging process, the injection charging pressure will make the blades inside the PVC pipe turn up, and at the same time, the blades outside the PVC pipe will be turned down and unfolded by the arc metal rod, so as to close the gap between the charging pipe and the wall of the rock drilling hole, reduce the returning of the powder explosives during the charging process, improve the charging utilization rate of the powder explosives, improve the charging site environment, and improve the rock blasting effect.

Description

Technical Field

[0001] This invention relates to a method for charging explosives in rock blasting, and more particularly to a method for preventing powder from returning to the hole when charging powdered explosives. Technical Background

[0002] Deep-hole blasting is a crucial technology for efficient mining in my country's metal mines. With the rapid development of my country's economy and society, the demand for metal mineral resources is gradually increasing, necessitating a shift towards large-scale and high-efficiency metal mining. Blasting drilling parameters are a significant factor affecting the production capacity and efficiency of metal mines. Drilling blasting holes within rock masses, especially the frequent switching of drilling rigs between holes, greatly increases the ineffective operating time of the drilling rig, wasting considerable time, manpower, and electricity. Therefore, deep-hole drilling and deep-hole blasting can effectively extend the continuous working time of the drilling rig, reducing the number of blasting holes required for the same blasting volume. This eliminates the need for time, manpower, and electricity wasted during hole switching, thereby improving the drilling efficiency of the rig and the blasting efficiency of the holes.

[0003] The backflow phenomenon of powdered explosives during deep-hole loading is a significant factor restricting deep-hole blasting. Rock powdered explosives are excellent industrial explosives, characterized by high explosive power, high construction efficiency, low toxic gas content, and safe storage, transportation, and use, making them widely used in my country's metal mines. These bulk explosives are typically injected into rock boreholes using air pressure. However, due to their dispersed nature, the high loading pressure during loading causes explosive powder to overflow through the gap between the loading tube and the borehole wall, resulting in a "backflow" phenomenon. This backflow is more severe when loading into deep holes, not only reducing the density of the powdered explosive within the borehole but also decreasing the loading efficiency, leading to explosive waste and adverse loading conditions, significantly limiting the advantages of deep-hole blasting. Summary of the Invention

[0004] To improve the efficiency of deep-hole charging of powdered explosives and leverage the advantages of intensive and efficient deep-hole blasting, this invention proposes a method to prevent powder backflow during deep-hole charging. This method utilizes internally and externally linked blades at the end of the powdered explosive charging tube. During charging, the internal blades flip upwards while the external blades unfold downwards, sealing the gap between the charging tube wall and the borehole wall. This effectively reduces powder backflow during deep-hole charging, thereby improving the charging efficiency and blasting effect.

[0005] The technical solution adopted by this invention to solve its technical problem is as follows:

[0006] ① First, cut a section of PVC pipe as the loading end;

[0007] ② Install a ring of hard plastic blades that can rotate up and down on the inner and outer pipe walls at the same position in the axial direction of the PVC pipe's loading end.

[0008] ③ Connect the inner and outer blades at the same radial position of the PVC pipe loading end with an arc-shaped metal rod that penetrates the PVC pipe wall.

[0009] ④ After connecting the PVC pipe charging end with hard plastic blades to the powdered explosive delivery pipe, insert it into the bottom of the rock borehole. While injecting powdered explosive into the rock borehole, gradually withdraw the charging pipe until the entire rock borehole is filled with powdered explosive.

[0010] The PVC pipe charging end in section ① must have anti-static properties. In order to facilitate the subsequent installation of the return powder blade, the length of the PVC pipe charging end should be 200-400mm, the outer diameter should be half the diameter of the blasting borehole in the rock mass, and the pipe wall thickness should be greater than 5mm.

[0011] The location for installing the plastic blade in step ② should preferably be in the middle of the axial direction of the PVC pipe loading end. The hard plastic blade must have anti-static function, the outer blade is rectangular, the inner blade is arc-shaped triangular, and the angle of the inner blade is θ = , where n = 5-10, and n is an integer. The specific value of n is determined by factors such as the outer diameter of the PVC pipe loading end, the hardness and strength of the blade.

[0012] The center angle of the arc-shaped metal rod in section ③ is 90°, ensuring that the two blades on the inner and outer sides of the PVC pipe's loading end wall are always perpendicular to each other, and that the metal rod can slide freely within the PVC pipe's loading end wall.

[0013] The inner diameter of the powdered explosive conveying pipe in section ④ should be equal to the outer diameter of the PVC pipe loading end for easy connection.

[0014] Before the connected powdered explosive charging tube in step ④ is inserted into the rock borehole, a portion of powdered explosive should be pre-placed above the inner blades of the PVC tube charging end. The weight of this portion of powdered explosive is used to ensure that the inner blades of the PVC tube charging end are in a horizontal position and the outer blades of the PVC tube charging end are in a vertical position close to the tube wall, so that the entire charging tube can be smoothly inserted into the rock borehole.

[0015] In step ④, during the process of loading explosives into the rock borehole, the injection pressure causes the blades located on the inner side of the PVC pipe loading end to flip upwards. At the same time, the curved metal rod drives the blades on the outer side of the PVC pipe loading end to flip downwards and unfold, sealing the gap between the PVC pipe loading end and the borehole wall of the rock mass, thus reducing the backflow of powder during the loading process of the powdered explosives.

[0016] The beneficial effects of this invention are as follows: the method for preventing powder backflow during the loading of powdered explosives into the borehole uses internal and external linkage blades set at the loading end of the PVC pipe. During loading, the internal blades flip upwards while the external blades unfold downwards, sealing the gap between the wall of the powdered explosive loading pipe and the wall of the rock borehole. This effectively reduces the degree of powder backflow during the loading of powdered explosives into the borehole and improves the loading efficiency and blasting effect of the powdered explosives. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings:

[0018] Figure 1 This diagram shows the positions of the inner and outer blades of the PVC pipe's loading end before loading.

[0019] Figure 2 This is a schematic diagram illustrating the linkage principle of the inner and outer blades at the end of a PVC pipe used for loading medicine.

[0020] Figure 3 This diagram shows the positions of the inner and outer blades of the PVC pipe's loading end during the loading process.

[0021] Figure 4 This diagram shows the connection between the PVC pipe charging end and the powdered explosive delivery pipe.

[0022] Figure 5 This is a schematic diagram showing the loading of explosives into a rock mass hole after the PVC pipe loading end is connected to the powdered explosive delivery pipe.

[0023] In the figure, 1. PVC pipe charging end, 2. outer blade, 3. inner blade, 4. metal connecting rod connecting the inner and outer blades, 5. powdered explosive delivery pipe, 6. powdered explosive, 7. rock borehole. Specific implementation methods

[0024] In the diagram, the steps for preventing powdered explosives from returning to the hole during loading are as follows:

[0025] ① First, cut a section of PVC pipe as the loading end 1;

[0026] ② Install a ring of hard plastic blades 2 and 3 that can rotate up and down on the inner and outer pipe walls at the same position in the axial direction of the PVC pipe loading end 1.

[0027] ③ Connect the inner and outer blades 2 and 3 at the same position in the radial direction of the PVC pipe loading end 1 with an arc-shaped metal rod 4 that penetrates the wall of the PVC pipe.

[0028] ④ After connecting the PVC pipe charging end 1 with hard plastic blades 2 and 3 to the powdered explosive delivery pipe 5, insert it into the bottom of the rock borehole 6. While injecting powdered explosive 7 into the rock borehole 6, gradually withdraw the charging pipe until the entire rock borehole 6 is filled with powdered explosive 7.

[0029] The PVC pipe charging end 1 in section ① must have anti-static function. In order to facilitate the subsequent installation of return powder blades 2 and 3, the length of the PVC pipe charging end 1 should be 200-400mm, the outer diameter should be half the diameter of the rock borehole 6, and the pipe wall thickness should be greater than 5mm.

[0030] The positions for installing the hard plastic blades 2 and 3 in step ② should preferably be selected at the middle of the axial direction of the PVC pipe loading end 1. The hard plastic blades 2 and 3 must have anti-static function, the outer blade 2 is rectangular in shape, the inner blade 3 is arc-shaped triangular in shape, and the angle θ of the inner blade 3 is , where n = 5-10, and n is an integer. The specific value of n is determined by factors such as the outer diameter of the PVC pipe loading end 1, the hardness and strength of the blades 2 and 3.

[0031] The center angle of the arc-shaped metal rod 4 in ③ is 90°, which ensures that the two blades 2 and 3, which are opposite each other inside and outside the PVC pipe loading end 1, are always perpendicular to each other, and the metal rod 4 can slide freely in the PVC pipe loading end 1.

[0032] The inner diameter of the powdered explosive conveying pipe 5 in section ④ should be equal to the outer diameter of the PVC pipe loading end 1 for easy connection.

[0033] Before the connected powdered explosive charging tube in step ④ is inserted into the rock borehole 7, a portion of powdered explosive 6 should be pre-placed above the inner blade 3 of the PVC pipe charging end 1. The weight of this portion of powdered explosive 6 is used to ensure that the inner blade 3 of the PVC pipe charging end is in a horizontal position and the outer blade 2 of the PVC pipe charging end 1 is in a vertical position close to the pipe wall, so that the entire charging tube can be smoothly inserted into the rock borehole 7.

[0034] In the process of loading explosives into the rock borehole 7, the injection pressure will cause the blade 3 located on the inner side of the PVC pipe loading end 1 to flip upwards. At the same time, the arc-shaped metal connecting rod 4 will drive the outer blade 2 of the PVC pipe loading end 1 to flip downwards and unfold, sealing the gap between the PVC pipe loading end 1 and the borehole wall of the rock borehole 7, and reducing the backflow of powder during the loading of the powdered explosive 6.

Claims

1. A method for preventing powder from returning to the hole during the loading of powdered explosives; characterized in that, Includes the following steps: First, cut a section of PVC pipe as the PVC pipe loading end (1). Then, a ring of hard plastic blades that can rotate up and down are installed on the inner and outer pipe walls at the same position in the axial direction of the PVC pipe loading end (1). The hard plastic blades include an outer blade (2) and an inner blade (3). Then, the outer blade (2) and inner blade (3) at the same position in the radial direction of the PVC pipe charging end (1) are connected by an arc-shaped metal rod (4) that penetrates the PVC pipe wall. The center angle of the arc-shaped metal rod (4) is 90°, ensuring that the outer blade (2) and inner blade (3) that are opposite to each other on the inner and outer sides of the PVC pipe charging end (1) are always perpendicular to each other, and the arc-shaped metal rod (4) can slide freely in the PVC pipe charging end (1) wall. Finally, the PVC pipe charging end (1) with the outer blade (2) and inner blade (3) installed is connected to the powdered explosive delivery pipe (5) and inserted into the bottom of the rock borehole (7). While injecting powdered explosive (6) into the rock borehole (7), the charging pipe is gradually withdrawn until the entire rock borehole (7) is filled with powdered explosive (6). Before the connected powdered explosive charging tube is inserted into the rock borehole (7), a portion of powdered explosive (6) should be pre-placed above the inner blade (3) of the PVC pipe charging end (1). The weight of this portion of powdered explosive (6) ensures that the inner blade (3) of the PVC pipe charging end (1) is in a horizontal position and the outer blade (2) of the PVC pipe charging end (1) is in a vertical position close to the pipe wall, so that the entire charging tube can be smoothly inserted into the rock borehole (7). During the loading of explosives into the borehole (7) in the rock mass, the injection pressure causes the inner blade (3) to flip upwards. At the same time, the outer blade (2) of the PVC pipe loading end (1) is flipped downwards and unfolded through the arc-shaped metal connecting rod (4), sealing the gap between the PVC pipe loading end (1) and the borehole wall (7) in the rock mass, thereby reducing the back-powdering phenomenon during the loading of powdered explosives (6).

2. A method for preventing powder backflow during the loading of powdered explosives into the hole, as described in claim 1; characterized in that: The PVC pipe charging end (1) has an anti-static function. The length of the PVC pipe charging end (1) is 200-400mm, the outer diameter is half the diameter of the rock borehole (7), and the pipe wall thickness is greater than 5mm.

3. A method for preventing powder backflow during the loading of powdered explosives into the hole, as described in claim 1; characterized in that: The hard plastic blade is located in the middle of the axial direction of the PVC pipe loading end (1), and the hard plastic blade has anti-static function. The outer blade (2) is rectangular in shape and the inner blade (3) is triangular in shape.

4. A method for preventing powder backflow during the loading of powdered explosives into the hole, as described in claim 1; characterized in that: The inner diameter of the powdered explosive delivery pipe (5) is equal to the outer diameter of the PVC pipe loading end (1).

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