Directional gas fracturing pipe and working method thereof

Abstract

The invention belongs to the technical field of geotechnical engineering and gas blasting, and provides a directional gas fracturing pipe and a working method thereof.The directional gas fracturing pipe comprises an inner pipe and an outer pipe arranged on the inner pipe in a sleeving mode; a guide assembly is arranged in a part of area of the outer pipe; the guide assembly comprises a guide area arranged on the outer pipe and an air guide hole formed in the guide area. The wall thickness of the guide area on the outer pipe is smaller than the wall thickness of other areas on the outer pipe; after the gas in the inner pipe is detonated, part of the gas escapes along the gas guide holes, the remaining gas expands and explodes outwards in the guide area, directional gas blasting is conducted on the rock area in the guide area, control over the gas fracturing rock direction is achieved, the phenomenon that the whole outer pipe is damaged due to gas blasting expansion is avoided, and recycling of the outer pipe is achieved.

Description

Technical Field

[0001] This invention belongs to the fields of geotechnical engineering and gas blasting technology, and particularly relates to a directional gas fracturing tube and its working method. Background Technology

[0002] Gas fracturing tube blasting is a novel blasting method for breaking rocks, replacing traditional explosive blasting. Current gas fracturing tubes typically consist of an outer tube, an inner tube filled with liquid gas, a heat-conducting mechanism, and an electric ignition head.

[0003] The current fracturing tube has the following two problems: First, the fracturing direction is difficult to control: The outer wall thickness of the fracturing tube is uniform and the strength of each area is consistent, which leads to a strong randomness in the location of the tube wall failure when the liquid gas expands due to heat, making it impossible to control the direction of the gas explosion. Second, the fracturing effect is difficult to achieve as expected: Due to the inability to control the fracturing direction, there is a phenomenon where the gas breaks up the rock but does not occur at the bottom of the hole or in the expected rock breaking area, which makes it impossible to complete the rock breaking work on time and in the required quantity, making it difficult to achieve the expected fracturing effect, requiring repeated work, and increasing the economic and time costs of the project. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a directional gas fracturing tube and its operating method. A guiding component is provided in a portion of the outer tube. The guiding component includes a guiding region on the outer tube and a gas guide hole opened within the guiding region. The wall thickness of the outer tube in the guiding region is less than the wall thickness of other regions on the outer tube. After the gas in the inner tube is detonated, some of the gas escapes along the gas guide hole, while the remaining gas expands and explodes outward within the guiding region, performing directional gas blasting on the rock area at the guiding region, thereby controlling the direction of gas-induced rock fracturing.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a directional gas fracturing tube, employing the following technical solution: A directional gas fracturing tube includes an inner tube and an outer tube sleeved on the inner tube; A guide component is provided on a portion of the outer tube; the guide component includes a guide area set in a preset area on the outer tube, and a gas guide hole opened in the guide area; the wall thickness of the guide area is less than the wall thickness of other areas on the outer tube; after the gas in the inner tube is detonated, part of the gas escapes along the gas guide hole, and the remaining gas expands and explodes outward in the guide area, performing directional gas blasting on the rock area at the guide area.

[0006] Furthermore, multiple air guide holes are uniformly arranged in an array within the guiding area; the air guide holes penetrate the inner tube and the outer tube.

[0007] Furthermore, the guide area is configured as a groove arranged along the axial direction of the outer tube, with openings at both ends of the groove, and the openings at both ends of the groove are flush with the two end faces of the outer tube.

[0008] Furthermore, a guide region with a wall thickness smaller than that of other parts is provided at the bottom end of the outer tube, and an air guide hole is opened in the guide region.

[0009] Furthermore, the vent is equipped with a plug to prevent the liquid gas in the inner tube from leaking out before detonation. At the same time, after detonation, as the internal pressure of the vent increases, the plug is pushed out.

[0010] Furthermore, the sealing component includes a sealing post and a first sealing ring disposed on the sealing post; the sealing post is inserted into the air guide hole, and the first sealing ring is located between the sealing post and the air guide hole after being compressed; the sealing post is an elastic post, and the outer diameter of the sealing post is larger than the inner diameter of the air guide hole.

[0011] Furthermore, a cap is provided at one end of the inner tube and the outer tube, and an electric ignition head, a feed pipe, and an exhaust pipe are respectively provided at three different positions on the cap; the electric ignition head is connected to a heat-conducting strip; the feed pipe, the exhaust pipe, and the heat-conducting strip all extend into the inner tube; the cap is divided into three areas, and the electric ignition head, the feed pipe, and the exhaust pipe are eccentrically positioned and located in the three areas respectively; the heat-conducting strip is located in the area close to the guide area 303, and the heat-conducting strip is close to the guide assembly inside the tube.

[0012] Furthermore, the inner wall of the end of the outer tube is provided with an internal thread, the plug is provided with an external thread that mates with the internal thread, and a second sealing ring is provided between the plug and the outer tube.

[0013] Furthermore, one end of the feed pipe extends to the bottom of the inner tube, and one end of the exhaust pipe is located at the top of the inner tube; the heat-conducting strip is located near the center of the area where the rock is to be broken.

[0014] To achieve the above objectives, in a second aspect, the present invention also provides a method for operating a directional gas fracturing tube, employing the following technical solution: A method for operating a directional gas fracturing tube, using the directional gas fracturing tube as described in the first aspect, includes: after the gas in the inner tube is detonated, a portion of the gas escapes along the gas guide hole, and the remaining gas expands and explodes outward in the guiding area, performing directional gas blasting on the rock area at the guiding area; when determining the directional blasting force, the relationship between the directional blasting force and the initial liquid gas pressure, the gas pressure after blasting, the surface area and thickness of the weak area, and the number of holes is as follows:

[0015]

[0016] Among them, F rock P1 is the explosive force for breaking rocks; P2 is the stress after the liquid gas explodes into gas upon heating; P0 is the initial stress of the liquid gas; A is the area of ​​the guiding region; K is the reduction coefficient of the hole; N is the number of holes; A s ρ is the lateral area of ​​a single hole. L V is the density of the liquid gas. L R is the volume of the liquid gas; T is the gas constant; K is the temperature at the time of explosion; and M is the molar mass of the gas.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a guiding component in a portion of the outer tube; the guiding component includes a guiding area on the outer tube and a gas guide hole opened in the guiding area; the wall thickness of the outer tube in the guiding area is less than the wall thickness of other areas on the outer tube; after the gas in the inner tube is detonated, part of the gas escapes along the gas guide hole, and the remaining gas expands and explodes outward in the guiding area, performing directional gas blasting on the rock area in the guiding area, thereby controlling the direction of gas-induced rock fracturing and avoiding the phenomenon of overall damage to the outer tube caused by gas blasting and expansion. Attached Figure Description

[0018] The accompanying drawings, which form part of this embodiment, are used to provide a further understanding of this embodiment. The illustrative embodiments and their descriptions are used to explain this embodiment and do not constitute an improper limitation of this embodiment.

[0019] Figure 1 This is a schematic diagram of the directional gas fracturing tube structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the air guide hole in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the sealing component according to Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the feed pipe and exhaust pipe of Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the cap structure in Embodiment 1 of the present invention; Figure 6 This is a schematic diagram showing the position of the guide component in Embodiment 2 of the present invention; Figure 7 This is a schematic diagram of the air guide hole in Embodiment 2 of the present invention; Among them, 1. Inner tube; 2. Outer tube; 201. Internal thread; 3. Guide assembly; 301. Air vent; 302. Sealing component; 3021. Sealing column; 3022. First sealing ring; 303. Guide area; 4. Plug cap; 401. Second sealing ring; 402. External thread; 403. Internal thread; 5. Electric ignition head; 6. Heat-conducting strip; 7. Feed pipe; 8. Exhaust pipe; 9. Steel wire clamp. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0022] Example 1: In the current field of underground engineering, blasting is frequently used for rock excavation. However, traditional blasting methods are criticized for being difficult to control and causing significant pollution. Gas fracturing tube blasting is a novel method for breaking rocks, intended to replace traditional explosive blasting. Current gas fracturing tubes typically consist of an outer tube, an inner tube filled with liquid gas, a heat-conducting mechanism, and an electric ignition head.

[0023] However, two problems remain unresolved regarding gas fracturing tubes in related technologies: First, the fracturing direction is difficult to control: Currently, the outer wall thickness of fracturing tubes is uniform, and the strength is consistent throughout. This leads to a highly random location of damage to the tube wall when the liquid gas expands due to heat, making it difficult to control the fracturing direction of the gas explosion. Moreover, the expansion of the gas explosion can also cause overall damage to the outer tube, making it unrecyclable and increasing costs. Second, the fracturing effect is difficult to achieve as expected: Due to the uncontrollable fracturing direction, there are instances where gas-induced rock fracturing does not occur at the bottom of the borehole or in the expected rock fracturing area. This results in the rock fracturing work not being completed on time and in sufficient quantity, failing to achieve the expected fracturing effect, requiring repeated work, and increasing both economic and time costs.

[0024] To solve the above problems, such as Figure 1 , Figure 2 and Figure 3 As shown, this embodiment provides a directional gas fracturing tube, including an inner tube 1, an outer tube 2, a guide assembly 3, a plug 4, an electric ignition head 5, a heat-conducting strip 6, a feed pipe 7, and an exhaust pipe 8, etc.

[0025] The inner tube 1 is mainly used to fill liquid gas; the feed pipe 7, the exhaust pipe 8 and the heat-conducting strip 6 all extend into the inner tube 1.

[0026] The outer tube 2 is sleeved on the inner tube 1; the outer tube 2 is on the outermost side of the fracture tube and is a measure to protect the inner tube from being damaged inside the borehole.

[0027] The guiding component 3 is disposed in a portion of the outer tube 2; optionally, the guiding component 3 includes a guiding region 303 disposed on the outer tube 2 and a gas guide hole 301 opened in the guiding region 303; the wall thickness of the outer tube 2 located in the guiding region 303 is less than the wall thickness of other regions on the outer tube 2; after the gas in the inner tube 1 is detonated, part of the gas escapes along the gas guide hole 301, and the remaining gas expands and explodes outward in the guiding region 303, performing directional gas blasting on the rock area at the guiding region 303.

[0028] Understandably, the wall thickness of the outer tube 2 located in the guide region 303 is less than the wall thickness of other regions on the outer tube 2. After the gas is detonated, it expands. Because the wall thickness of the guide region 303 is smaller, the expanding gas preferentially expands and explodes in the guide region 303. Other regions of the outer tube 2, due to their larger wall thickness, will not expand and explode. This not only achieves directional blasting in the guide region 303, but also ensures the integrity of other regions of the outer tube 2, enabling recycling.

[0029] The vent 301 can penetrate both the inner tube 1 and the outer tube 2, ensuring that some gas escapes along the vent 301. Based on the vent 301, during operation, after the gas in the inner tube 1 is detonated, some gas escapes along the vent, providing initial guidance for the blasting direction; then, the remaining gas expands and explodes outward within the guiding area, achieving directional gas blasting of the rock area in the guiding region.

[0030] Optionally, multiple air guide holes 301 are uniformly arranged in an array within the guide area 303. After the gas is detonated, it expands, and some of the gas escapes simultaneously from the multiple air guide holes 301. This ensures the uniformity of the expansion force acting on each point within the entire guide area 303, and ensures the uniformity of the blasting impact force distribution throughout the entire guide area 303. This improves the effect on the blasted rock area and avoids the problem of uneven blasting degree within the blasted rock area.

[0031] The guide region 303 is configured as a groove along the axial direction of the outer tube 2, with openings at both ends, flush with the end faces of the outer tube 2. When the bottom surface of the guide region 303 is impacted by expanding gas, the outer tube 2 ruptures within the guide region 303, forming an opening. During the gas explosion, the portions of the outer tube 2 located on both sides of the opening undergo outward overall deformation, ensuring the overall structural integrity of the outer tube 2 and preventing excessive local deformation caused by excessive local stress. This ensures the overall structural integrity of the outer tube 2 and facilitates recycling. However, if the groove is not open at both ends, when the bottom surface of the guide region 303 is impacted by expanding gas, the outer tube 2 ruptures within the guide region 303. During the gas explosion, the outer tube 2 also undergoes significant deformation along the periphery of the guide region 303, causing the overall structure of the outer tube 2 to become distorted or affecting overall deformation, thus failing to guarantee the overall structural integrity of the outer tube 2.

[0032] In summary, in order to achieve directional rock breaking, a certain number of vent holes 301 are drilled on the pipe wall surface in the area where the rock needs to be broken, so that the gas can escape from here by explosion. At the same time, the pipe wall thickness in the rock breaking area is relatively thinner than in other places. This double protection measure is conducive to the expansion gas expanding outward and exploding through the weak point of the pipe wall. It can not only achieve the purpose of directional rock breaking, but also ensure the recycling and reuse of the fracturing pipe, thereby reducing costs.

[0033] In this embodiment, the vent 301 is provided with a sealing element 302. The sealing element 302 is provided to prevent the liquid gas in the inner tube 1 from overflowing before detonation. At the same time, after detonation, as the internal pressure of the vent 301 increases, the sealing element 302 can be pushed out, thus ensuring the guiding effect of the expanding gas.

[0034] The sealing component 302 includes a sealing post 3021 and a first sealing ring 3022 disposed on the sealing post 3021. The sealing post 3021 is inserted into the air guide hole 301 to perform a sealing function. After being squeezed, the first sealing ring 3022 is located between the sealing post 3021 and the air guide hole 301, which improves the sealing performance and prevents the leakage of liquid gas in the inner tube 1 before detonation.

[0035] Optionally, the sealing post 3021 is an elastic post, and the outer diameter of the sealing post 3021 is larger than the inner diameter of the gas guide hole 301. The sealing post 3021 can be stably set in the gas guide hole 301 through elasticity, with good sealing performance. After the gas is ignited, under the action of gas expansion force, the elastic property of the sealing post 3021 allows it to be smoothly moved out of the gas guide hole 301.

[0036] In summary, the sealing element 302 can ensure that there is a certain pressure inside the inner tube 1; the main function of the sealing element 302 is to seal the gas guide hole 301 while filling with liquid gas to prevent liquid and gas leakage; when the gas is heated and explodes, due to the excessive internal pressure, the sealing element 302 is pushed out, guiding the explosive gas to directionally explode the expected rock along the gas guide hole 301.

[0037] A plug 4 is provided at one end of the inner tube 1 and the outer tube 2, so that a sealed space is formed inside the inner tube 1; one end of the inner tube 1 is closed, and the other end is open for installing the plug 4.

[0038] Optionally, the inner wall of the end of the outer tube 2 is provided with an internal thread 201, and the plug cap 4 is provided with an external thread 402 that mates with the internal thread 201. A second sealing ring 401 is provided between the plug cap 4 and the outer tube 2. The engagement of the internal thread 201 and the external thread 402 ensures a tight connection between the plug cap 4 and the outer tube 2, while the addition of the second sealing ring 401 ensures a tight seal. Figure 4 and Figure 5 As shown, an electric ignition head 5, a feed pipe 7, and an exhaust pipe 8 are respectively provided at three different positions on the plug cap 4; the electric ignition head 5 is connected to a heat-conducting strip 6; the feed pipe 7, the exhaust pipe 8, and the heat-conducting strip 6 all extend into the inner tube 1.

[0039] Understandably, the plug cap 4 is divided into three zones, with the electric ignition head 5, the feed pipe 7, and the exhaust pipe 8 eccentrically positioned within each zone; correspondingly, the heat-conducting strip 6 is located near the guide zone 303. One end of the feed pipe 7 extends to the bottom of the inner tube 1, and one end of the exhaust pipe 8 is located at the top of the inner tube 1. The feed pipe 7 ensures that liquid gases, such as liquid oxygen or liquid nitrogen, can be smoothly filled into the fracturing tube; the exhaust pipe 8 ensures that the gas in the inner tube 1 is completely discharged, guaranteeing the purity of the liquid gas and maximizing the efficiency of the fracturing tube.

[0040] The electric ignition head 5 is connected to an external electrification structure, transferring heat to the heat-conducting strip 6, causing the internal liquid gas to expand instantaneously, achieving the purpose of explosion. In this embodiment, the electric ignition head 5 and the heat-conducting strip 6 are eccentrically positioned, so that the heat-conducting strip 6 is close to the guide component 3 inside the tube. The eccentric position of the heat-conducting strip 6 in the inner tube 1 will facilitate directional explosion. Optionally, depending on the location and size of the directional blasting rock area, the circumference of the inner tube 1 can be divided into 3 or 4 blocks, with the heat-conducting strip 6 positioned close to the center of the expected rock-breaking area, i.e., eccentric. The number and length of the heat-conducting strip 6 can also vary with the size of the area. With this arrangement, when the gas is heated and explodes, the gas in different blocks will be detonated sequentially, thereby ensuring directional rock breaking.

[0041] The directional gas fracturing tube used in this implementation is a reusable device for directional rock fracturing, which can be selectively filled with liquid media such as liquid nitrogen or liquid oxygen. It is particularly suitable for scenarios with high requirements for blasting efficiency and controllability, such as rock anchor beam blasting removal, mining, and tunnel construction. A directional gas fracturing tube that can achieve directional fracturing, improve fracturing efficiency, ensure efficient blasting of rock within the expected area, and be recyclable after completing the fracturing task is of great importance.

[0042] The air guide holes 301 are located at the bottom of the outer tube 2 and at the connection point of the outer tube 2, radially distributed along the fracturing tube. The hole spacing and width can be adjusted according to the strength of the rock. The sealing post 3021 structure of the sealing component 302 seals the air guide holes 301, reducing the manpower required for the sealing process, saving time, and improving efficiency. This embodiment ensures that the expanding gas is released from the air guide holes 301, precisely and directionally destroying the rock. Steel wire clamps 9 are applied to areas of the outer tube 2 where fracturing is not required. Optionally, multiple steel wire clamps 9 are arranged axially on the outer tube 2 for local and / or overall reinforcement, and to solve the problem that the gas cannot meet the blasting requirements of some tunnels. The two ends of the steel wire of the steel wire clamp 9 can be equipped with knobs, buckles, or other quick-connection methods to ensure that the steel wire clamp 9 is quickly installed on the outer tube 2.

[0043] One working process or principle of this embodiment is as follows: With the help of the external filling structure, liquid gas is filled into the inner tube 1 through the feed pipe 7, and the internal air is discharged through the exhaust pipe 8. The entire fracturing tube is sealed with the plug cap 4 structure. A closed space is formed inside the inner tube 1. The heat is then conducted to the heat conduction strip 6 through the electric ignition head 5, causing the internal liquid gas to burn or expand and explode into a large amount of gas. The gas enters the gap between the fracturing tube and the rock through the guide component 3, achieving the purpose of directional rock fracturing.

[0044] Example 2: like Figure 6 and Figure 7 As shown, this embodiment provides a directional gas fracturing tube. Unlike embodiment 1, the guide component 3 in this embodiment is not disposed on the side wall of the outer tube 2, but is disposed at the bottom end of the entire directional gas fracturing tube. Optionally, the inner tube 1 extends the outer tube 2 from the bottom end of the directional gas fracturing tube, and the extension section serves as a guide area 303. A gas guide hole 301 is provided in the extension section. In this case, the guide area 303 does not need to be opened on the outer tube 2, the wall thickness of the entire outer tube 2 is uniform, and the heat-conducting strip 6, the feed pipe 7, and the exhaust pipe 8 do not need to be eccentrically disposed.

[0045] Alternatively, a guide region 303 with a wall thickness smaller than that of other parts is provided at the bottom end of the outer tube 2, and an air guide hole 301 is opened in the guide region 303.

[0046] Example 3: This embodiment provides a method for operating a directional gas fracturing tube, which uses a directional gas fracturing tube as described in Embodiment 1 or Embodiment 2, including: after the gas in the inner tube 1 is detonated, part of the gas escapes along the gas guide hole 301, and the remaining gas expands and explodes outward in the guide area 303, thereby performing directional gas blasting on the rock area at the guide area 303.

[0047] During blasting, it is necessary to determine the theoretical directional blasting force to make a preliminary judgment on whether the directional blasting force is satisfied. In this implementation, when determining the directional blasting force, the relationship between the directional blasting force and the initial liquid gas pressure, the gas pressure after blasting, the surface area and thickness of the weak area, and the number of holes is as follows:

[0048]

[0049] Among them, F rock P1 is the explosive force for breaking rocks, in Newtons (N); P2 is the stress of the liquid gas after being heated and exploding into gas, in Pascals (Pa); P0 is the initial stress of the liquid gas, in Pascals (Pa); A is the area of ​​the guiding region, in square meters (㎡); K is the reduction coefficient of the holes, generally taken as 0.1~0.5 (the more holes, the larger the value); N is the number of holes; A s ρ is the lateral area of ​​a single hole, in square meters (㎡); L The density of liquid gases is typically 1140 kg / m³ for liquid oxygen and 808 kg / m³ for liquid nitrogen; V L R is the volume of the liquid gas, in cubic meters (m³); R is the gas constant, 8.314 J / (mol). K); T is the temperature at the time of explosion; K is the gas molar mass.

[0050] The above description is merely a preferred embodiment of this practice and is not intended to limit the scope of this practice. Various modifications and variations can be made to this practice by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this practice should be included within the protection scope of this practice.

Claims

1. A directional gas fracturing tube, characterized in that, It includes an inner tube and an outer tube fitted onto the inner tube; A guide component is provided on a portion of the outer tube; the guide component includes a guide area set in a preset area on the outer tube, and a gas guide hole opened in the guide area; the wall thickness of the guide area is less than the wall thickness of other areas on the outer tube; after the gas in the inner tube is detonated, part of the gas escapes along the gas guide hole, and the remaining gas expands and explodes outward in the guide area, performing directional gas blasting on the rock area at the guide area.

2. The directional gas fracturing tube as described in claim 1, characterized in that, Multiple air guide holes are evenly arranged in an array within the guiding area; the air guide holes penetrate the inner tube and the outer tube.

3. The directional gas fracturing tube as described in claim 1, characterized in that, The guide area is configured as a groove arranged along the axial direction of the outer tube, with openings at both ends of the groove, and the openings at both ends of the groove are flush with the two end faces of the outer tube.

4. A directional gas fracturing tube as described in claim 1, characterized in that, A guide area with a wall thickness smaller than that of other parts is provided at the bottom end of the outer tube, and an air guide hole is opened in the guide area.

5. A directional gas fracturing tube as described in claim 1, characterized in that, The vent is equipped with a plug to prevent the liquid gas in the inner tube from leaking out before detonation. After detonation, the plug is pushed out as the pressure inside the vent increases.

6. A directional gas fracturing tube as described in claim 5, characterized in that, The sealing component includes a sealing post and a first sealing ring disposed on the sealing post; the sealing post is inserted into the air guide hole, and the first sealing ring is located between the sealing post and the air guide hole after being compressed; the sealing post is an elastic post, and the outer diameter of the sealing post is larger than the inner diameter of the air guide hole.

7. A directional gas fracturing tube as described in claim 1, characterized in that, A cap is provided at one end of the inner tube and the outer tube. An electric ignition head, a feed pipe, and an exhaust pipe are respectively provided at three different positions on the cap. The electric ignition head is connected to a heat-conducting strip. The feed pipe, the exhaust pipe, and the heat-conducting strip all extend into the inner tube. The cap is divided into three areas. The electric ignition head, the feed pipe, and the exhaust pipe are eccentrically positioned and located in the three areas respectively. The heat-conducting strip is located in the area close to the guide area 303. The heat-conducting strip is located inside the tube close to the guide assembly.

8. A directional gas fracturing tube as described in claim 1, characterized in that, The inner wall of the end of the outer tube is provided with an internal thread, and the plug is provided with an external thread that mates with the internal thread. A second sealing ring is provided between the plug and the outer tube.

9. A directional gas fracturing tube as described in claim 8, characterized in that, One end of the feed pipe extends to the bottom of the inner pipe, and one end of the exhaust pipe is located at the top of the inner pipe; the heat-conducting strip is located near the center of the area where the rock is to be broken.

10. A method for operating a directional gas fracturing tube, characterized in that, The directional gas fracturing tube as described in any one of claims 1-9 is used, comprising: after the gas in the inner tube is detonated, part of the gas escapes along the gas guide hole, and the remaining gas expands and explodes outward in the guiding area to perform directional gas blasting on the rock area at the guiding area; when determining the directional blasting force, the relationship between the directional blasting force and the initial liquid gas pressure, the gas pressure after blasting, the surface area and thickness of the weak area, and the number of holes is as follows: Among them, F rock P1 is the explosive force for breaking rocks; P2 is the stress after the liquid gas explodes into gas upon heating; P0 is the initial stress of the liquid gas; A is the area of ​​the guiding region; K is the reduction coefficient of the hole; N is the number of holes; A s ρ is the lateral area of ​​a single hole. L V is the density of the liquid gas. L R is the volume of the liquid gas; T is the gas constant; K is the temperature at the time of explosion; and M is the molar mass of the gas.

Images