Static fracturing structure for high-energy expansion capsule
By setting up a static fracturing structure of high-energy expansion capsules in the coal mining area and using high-pressure water injection to trigger the capsule reaction to produce gas, the safety risks and construction difficulties of hard roof treatment in the existing technology are solved, and the effective weakening of hard coal/rock formations is achieved.
Patent Information
- Application Number
- CN202422911301.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-28
- Publication Date
- 2025-09-23
- Estimated Expiration
- 2034-11-28
AI Technical Summary
Existing technologies for dealing with hard roofs in coal mining have problems such as high safety risks, great construction difficulty, and unstable results. In particular, traditional blasting and hydraulic fracturing methods have limited effectiveness under specific conditions.
The static fracturing structure of high-energy expansion capsules is adopted. By setting multiple groups of drill holes in the mining tunnels, working faces or roofs, high-energy expansion capsules are placed, and high-pressure water is injected using a pneumatic booster water pump and a pipeline system to trigger the capsule reaction to produce gas, thereby achieving static fracturing.
It achieves safe and reliable weakening of hard coal/rock strata with simple construction, avoids the safety risks and construction difficulties of traditional methods, and has significant effects.
Smart Images
Figure CN223374409U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a static fracturing structure for a high-energy expansion capsule. Background Art
[0002] Underground mining dominates coal mining in my country, and roof management in goafs is crucial for ensuring mine safety. While the traditional "full collapse" method is widely used, in practice, many mines face the problem of large areas of suspended roof behind the working face. If not promptly addressed, this suspended roof phenomenon can lead to prolonged concentrated pressure on the goaf roof, increasing the difficulty of roof management and posing a serious threat to mine safety.
[0003] There are many methods for dealing with hard roof, such as shallow hole blasting, deep hole pre-splitting blasting, water injection softening, hydraulic fracturing, etc. Each method has its limitations, such as construction difficulty, environmental adaptability, cost and labor intensity. Common methods for weakening hard coal / rock formations include: drilling blasting and hydraulic fracturing. However, drilling blasting and hydraulic fracturing have their limitations. Using blasting to weaken roof coal / rock formations is a technology for weakening hard coal / rock formations in coal mining, but it itself has high safety risks, high technical requirements, may induce rock burst, and the blasting effect is also unstable. In addition, when encountering particularly hard roof coal, it may be difficult to achieve the ideal weakening effect by blasting alone, and it needs to be combined with other technical means. Hydraulic fracturing involves injecting high-pressure water into the target coal / rock mass, squeezing and fracturing the surrounding rock through the high-pressure water. This technology is suitable for intact rocks, but when the coal / rock mass has well-developed cracks, it is prone to pressure leakage, making the high-pressure water ineffective in causing fractures. The use of gas pressure fracturing is a technology currently being researched and implemented, but this method requires a reasonable structure for implementation. Summary of the Invention
[0004] In view of the above problems, the purpose of the present invention is to provide a static fracturing structure for a high-energy expansion capsule, through which the hard coal / rock layer in the mining area can be weakened.
[0005] In order to achieve the above purpose, the solution of the utility model is:
[0006] A static fracturing structure for high-energy expansion capsules, which is arranged in a mining tunnel, working face or roof, and is used for weakening hard coal / rock strata, wherein: the static fracturing structure includes multiple groups of drill holes distributed in the mining tunnel, working face or roof, the spacing between drill holes in each group of drill holes is no more than 600 mm, the diameter of each drill hole is 40 mm to 70 mm, and the drilling depth is 4.5 m to 10 m. The high-energy expansion capsules are placed in the drill holes, and a plugging expansion pipe is set at the drill hole mouth. The output of a pneumatic booster water pump is connected to two pipelines, one is a fracturing high-pressure water pipe, and the other is a plugging high-pressure water pipe. The fracturing high-pressure water pipe passes through the plugging expansion pipe through a first high-pressure valve and is placed in the drill hole. The plugging high-pressure water pipe is connected to the plugging expansion pipe interface through a second high-pressure valve.
[0007] The solution is further that the number of holes in each group of holes is 4 to 6, and the holes in each group are distributed in a rectangular or right-angled shape.
[0008] The solution is further that the drill hole is inclined at an angle of 55 to 85 degrees to the excavation working face or top plate.
[0009] A further solution is that a main valve with a pressure gauge is provided between the pneumatic booster water pump and the two output pipelines.
[0010] A further solution is: the high-energy expansion capsule is a glass bottle or plastic bottle with a diameter of no more than 40 mm, the bottle is filled with chemical powder that reacts with water to produce gas, and the glass bottle or plastic bottle breaks under a certain water pressure.
[0011] A further solution is that the volume of the high-energy expansion capsule is at least half of the drilling volume.
[0012] The beneficial effects of the utility model are: the structure is simple to implement, and the structure can be used to achieve the weakening of hard coal (rock) layers at the coal (rock) roadway excavation working face, which is safe and reliable.
[0013] The present invention is described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 This is a schematic diagram of the static cracking structure of the utility model;
[0015] Figure 2 This is a schematic diagram of the planar structure of each group of drilling holes in the utility model;
[0016] Figure 3 It is a schematic diagram of the cross-sectional structure of the tunnel roof drilling of the utility model. DETAILED DESCRIPTION
[0017] A static fracture structure for high energy expansion capsules, e.g. Figure 1 、 Figure 2 and Figure 3 As shown, the static fracturing structure is set in the mining tunnel, working face or roof to weaken the hard coal / rock layer, where: Figure 2 As shown, the static fracturing structure includes a plurality of drill holes 1 distributed in the tunnel, working face or roof, for example Figure 3 As shown, a row of multiple groups of upward boreholes 101 are set on the top plate of the tunnel. The spacing between the boreholes 101 in each group of boreholes is not more than 600 mm, the diameter of each borehole 101 is 40 mm to 70 mm, and the drilling depth is 4.5 m to 10 m. The high-energy expansion capsule 2 is placed in the borehole, and a sealing expansion tube 3 (closed expansion tube) is set at the borehole mouth. The expansion tube 3 in this embodiment uses a steel belt rubber tube, and the length is set as needed. In this embodiment, it is 0.5 to 1 meter. An pneumatic booster water pump 4 outputs two pipelines, one is a fracturing high-pressure water pipe 5, and the other is a blocking high-pressure water pipe 6. The fracturing high-pressure water pipe 5 passes through the blocking expansion pipe 3 through the first high-pressure valve 7 and is placed in the borehole 101. The fracturing high-pressure water pipe 5 is sealed and welded to the blocking end of the blocking expansion pipe 3 at both ends of the blocking expansion pipe 3. The blocking high-pressure water pipe 6 is connected to the blocking expansion pipe interface 301 through the second high-pressure valve 8. The pneumatic booster water pump 4 is connected to a water source and an air source. A main valve 9 is provided between the pneumatic booster water pump 4 and the two output pipelines. The main valve 9 has a pressure gauge 901 .
[0018] The closed expansion pipe 3 is filled with water and pressurized to a certain pressure, and then the second high-pressure valve 8 is closed, so that the static friction between the expansion pipe 3 and the borehole wall reaches a sufficient strength for sealing.
[0019] like Figure 2 As shown: the number of holes in each group of holes is 4 to 6, and the holes in each group are distributed in a rectangular or right-angled shape.
[0020] Figure 3 Middle: The borehole 101 is inclined at an angle a of 55 to 85 degrees to the excavation working face or roof.
[0021] The high-energy expansion capsule is a glass or plastic bottle with a diameter of no more than 40 mm, which contains chemical powder or liquid that reacts with water to produce gas. The strength of the glass or plastic bottle is set to break under a certain water pressure. The volume of the high-energy expansion capsule is at least half of the drilled hole volume.
[0022] The static fracturing principle of the high-energy expansion capsule in this embodiment is as follows: After the structure is completed, a pneumatic booster pump 4 is used to first inject water into the expansion tube 3 and pressurize it to a certain pressure, then seal the borehole. High-pressure water is then poured into the borehole. When the water pressure reaches or approaches 2 MPa, the glass or plastic capsule bottle is squeezed and ruptured. The chemical powder or liquid in the capsule combines with the high-pressure water to produce a chemical reaction, quickly generating a large amount of water-insoluble gas. This causes the pressure in the borehole to rapidly increase to 40-50 MPa, which then acts on the surrounding rock mass, achieving static fracturing of the rock mass. In practice, the fracturing effect is significant within the structural dimensions of this embodiment. At the moment of fracturing, the water pressure drops rapidly. At this point, the booster pump 4 and the first high-pressure valve 7 are shut off. After a pause, the pressure is relieved, expelling the gas, water, and any remaining gas in the borehole. Once the pressure gauge reading drops below 5 MPa, the site can be vacated. This structure can weaken hard coal / rock formations, is simple to construct, and is safe and reliable.
Claims
1. A static fracturing structure for high-energy expansion capsules, which is installed in mining tunnels, working faces or roofs for weakening hard coal / rock formations, characterized in that: The static fracturing structure includes multiple groups of drill holes distributed in the excavation tunnel, working face or roof. The spacing between the drill holes in each group of drill holes is not more than 600 mm, the diameter of each drill hole is 40 mm to 70 mm, and the drilling depth is 4.5 m to 10 m. The high-energy expansion capsule is placed in the drill hole, and a sealing expansion pipe is set at the drill hole mouth. The output of a pneumatic booster water pump is connected to two pipelines, one is a fracturing high-pressure water pipe, and the other is a sealing high-pressure water pipe. The fracturing high-pressure water pipe passes through the sealing expansion pipe through a first high-pressure valve and is placed in the drill hole. The sealing high-pressure water pipe is connected to the sealing expansion pipe interface through a second high-pressure valve.
2. The static fracture structure according to claim 1, characterized in that: The number of holes in each group of holes is 4 to 6, and the holes in each group are distributed in a rectangular or right-angled shape.
3. The static fracture structure according to claim 1, characterized in that: The borehole is inclined at an angle of 55 to 85 degrees to the excavation working surface or the top plate.
4. The static fracture structure according to claim 1, characterized in that: A main valve with a pressure gauge is provided between the pneumatic booster water pump and the two output pipelines.
5. The static fracture structure according to claim 1, characterized in that: The high-energy expansion capsule is a glass bottle or plastic bottle with a diameter of no more than 40 mm. The bottle contains chemical powder that reacts with water to generate gas. The glass bottle or plastic bottle breaks under a certain water pressure.
6. The static fracture structure according to claim 1, characterized in that: The volume for placing the high-energy expansion capsule occupies at least one half of the drilling volume.