A visualization device for long-distance directional drilling and multi-stage hydraulic fracturing in coal mines

Abstract

The present invention relates to the field of mining engineering technology, and specifically to a long-distance directional drilling multi-stage hydraulic fracturing visualization device for underground coal mines, comprising a ground component and a hydraulic fracturing component, wherein the hydraulic fracturing component comprises a high-pressure steel pipe, a packer, a fracturing pipe, a video line 2, a unit hose and a visualization camera, wherein the high-pressure steel pipe can be freely assembled and combined in length according to the length of the construction borehole to meet the requirements of hydraulic fracturing construction operations under various conditions, the packer is used to expand and contract under the action of water pressure, the packer is used to seal the borehole, the fracturing pipe is used to be installed between two packers, and a plurality of water outlets are provided on the fracturing pipe. In the present invention, by setting up a plurality of packers and fracturing pipes, the number of fracturing pipes can be freely combined according to the actual mine construction situation, so as to realize hydraulic fracturing of different sections at the same time, and the line and pipeline connection is simple and efficient, which greatly shortens the hydraulic fracturing operation cycle, and is easy to operate and has a wide range of applications.

Description

Technical Field

[0001] The invention relates to the technical field of mining engineering, in particular to a long-distance directional drilling multi-stage hydraulic fracturing visualization device in an underground coal mine. Background Art

[0002] The long-distance directional drilling hydraulic fracturing technologies currently used are mainly surface fracturing and downhole fracturing. Surface fracturing involves drilling a hole on the ground to the desired fractured layer, which can pre-crack the roof and reduce the occurrence of strong mine pressure during coal seam mining. However, surface fracturing is expensive, and if the target fractured layer is buried deep, the cost will increase exponentially. Downhole fracturing involves using a kilometer-long directional drilling rig to drill a hole underground to the desired fractured layer and perform fracturing. This method is low-cost and has a wide range of applications, and has been promoted and applied in recent years. However, the fracturing method currently adopted in downhole long-distance directional drilling technology is one-stage-one-fracturing. When applied to long-distance drilling, this method has problems such as a large number of fracturing stages and severe repetitive operations, which significantly increases the operation cycle and is not conducive to mining and excavation succession. Therefore, the idea of ​​multi-stage hydraulic fracturing technology has been proposed to achieve the fracturing of multiple hole sections at a time, alleviate the problem of repetitive operations, and shorten the fracturing cycle.

[0003] Hydraulic fracturing technology has matured. For example, patent publication number CN114961682B discloses a hydraulic fracturing device and its fracturing construction method. The device comprises at least two packers, each connected in series by a high-pressure pipe. The hollow steel pipe between the two packers is equipped with a water hole connected to the borehole. Because the packers are used for fracturing, they can be fixed at any position in the borehole as designed, achieving precise fracturing of hard coal and rock formations. Furthermore, the packers can be sequentially moved to the next section within the same borehole after the previous section is fracturing, thereby fracturing thick, hard rock formations in sections. However, the aforementioned patent uses only two packers and a dual-seal fracturing method, which can only fracture one section of the borehole at a time. When drilling long boreholes, repeated operations are common, the fracturing cycle is too long, and the time cost is high, which seriously affects the recovery and connection of the working face. Summary of the Invention

[0004] The purpose of the present invention is to provide a long-distance directional drilling multi-stage hydraulic fracturing visualization device for underground coal mines to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A long-distance directional drilling multi-stage hydraulic fracturing visualization device for underground coal mines, comprising a ground component and a hydraulic fracturing component, wherein the hydraulic fracturing component comprises:

[0007] High-pressure steel pipes can be freely assembled and combined in length according to the length of the construction drilling hole to meet the hydraulic fracturing construction operations under various conditions;

[0008] Packers, which expand and contract under water pressure, are used to seal boreholes;

[0009] The fracturing pipe is installed between two packers. The fracturing pipe is provided with multiple water outlets. Multiple packers and fracturing pipes can be freely combined and connected according to the construction conditions to achieve simultaneous hydraulic fracturing of different sections.

[0010] Visual camera to collect images inside the borehole;

[0011] Video cable 2, used to connect to the packer, provide power to the visualization camera in the borehole, and transmit the collected images to the computer;

[0012] Unit hose, used to connect adjacent packers;

[0013] The ground assembly includes:

[0014] Directional drilling rigs, used to move the entire hydraulic fracturing assembly within the borehole;

[0015] High-pressure pumps, used to pump fracturing fluid and control packer expansion and contraction;

[0016] The drilling visualization imager is connected to the visualization camera through video line 2 and is used to display the image of the surrounding rock inside the drilling hole.

[0017] Furthermore, a water pipe and a fracturing fluid pipe are installed on the output end of the high-pressure pump, the fracturing fluid pipe is used to connect with the high-pressure steel pipe, the water pipe can be connected with the unit hose, valve one is installed on the water pipe, valve two is installed on the fracturing fluid pipe, and a pressure relief valve is installed on the water pipe.

[0018] Furthermore, a pressure sensor 1 is installed on the water pipe, a pressure sensor 2 is installed on the fracturing fluid pipe, a recorder is provided on one side of the pressure sensor 1, the recorder is data-connected with the pressure sensor 1 and the pressure sensor 2, and the recorder is used to record the internal pressure conditions of the packer and the fracturing pipe in real time.

[0019] Furthermore, the packer includes a channel tube, both ends of the channel tube and both ends of the fracturing tube are provided with threaded interfaces, the fracturing tube can be screwed and connected with the channel tube, a balloon is installed on the channel tube, both ends of the channel tube are installed with data cable adapters, a video cable 1 is fixedly installed between the two data cable adapters, the data cable adapter is used to connect with video cable 2, and both ends of the channel tube are provided with waterway adapters, the waterway adapter is used to connect with the unit hose.

[0020] Furthermore, the multiple water outlets on the fracturing pipe are divided into two rows and are respectively arranged on both sides of the fracturing pipe. A driving paddle is provided inside one end of the fracturing pipe. Both ends of the driving paddle are rotatably connected to a fixed seat, which is fixedly installed between the fixed seat and the inner wall of the fracturing pipe. A rotating roller is fixedly installed at one end of the driving paddle. The rotating roller includes three annular shielding blades arranged at equal angles. The shielding blades are used to shield the water outlet.

[0021] Furthermore, a gap is provided between the shielding blades and the inner wall of the fracturing pipe.

[0022] Furthermore, a partition plate is fixedly installed on the inner wall of the other end of the fracturing pipe, and a rotation opening is opened on the outer wall of the other end of the fracturing pipe.

[0023] Furthermore, a balancing valve is installed on one side of the channel pipe, and the balancing valve is used to balance the pressure in the packer and the pressure in the fracturing pipe.

[0024] Furthermore, the balancing valve component includes a fixed tube, an insertion shaft is slidably inserted into the fixed tube, one end of the insertion shaft is fixedly installed on the inner wall of the balloon, a connecting tube is installed between one end of the fixed tube and the channel tube, and the outer side wall of the other end of the fixed tube is fixedly connected to a liquid outlet tube.

[0025] Furthermore, a slide is fixedly connected to the outer wall of the liquid outlet pipe, a valve head is slidably connected to the slide, one end of the valve head is slidably plugged into the liquid outlet pipe, and a return spring is fixedly installed between the other end of the valve head and the slide.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. Through the setting of multiple packers and fracturing tubes, multiple fracturing tubes are assembled through high-pressure steel pipes and packers. Video line 2 and unit hoses are connected between two adjacent packers. The connection between the high-pressure pump and the water pipe and fracturing fluid pipe is checked. The cracks on the inner wall of the borehole are observed through the visual camera. The high-pressure pump is started and low-pressure water is injected into the multiple packers through the unit hose to expand the packers until they are in contact with the hole wall and fixed. After a closed space is formed between two adjacent packers, the high-pressure pump is used to inject high-pressure water into the fracturing tubes. The number of fracturing tubes can be freely combined according to the actual mine construction situation to realize hydraulic fracturing of different sections at the same time. The line and pipeline connection is simple and efficient, which greatly shortens the hydraulic fracturing operation cycle. It is easy to operate and has a wide range of applications.

[0028] 2. Through the setting of the fracturing pipe, when the height position of the hydraulic fracturing assembly is adjusted, the high-pressure pump injects low-pressure liquid into the high-pressure steel pipe through the fracturing liquid pipe, driving the driving paddle to rotate, and the driving paddle drives the rotating roller to rotate. Through the setting of multiple shielding blades on the rotating roller, the water outlets on both sides of the fracturing pipe are opened in turn, so that the liquid is sprayed out from both sides of the fracturing pipe in turn, thereby driving the top of the hydraulic fracturing assembly to shake left and right, thereby preventing the top of the hydraulic fracturing assembly from getting stuck on the hole wall;

[0029] 3. Through the setting of the balancing valve, the balloon expands to seal the borehole. At this time, the plug shaft releases the blockage on one end of the connecting pipe. When the pressure in the channel pipe gradually rises and the water pressure in the channel pipe is higher than the water pressure in the packer, the liquid in the channel pipe pushes open the valve head and enters the balloon, so that the hydraulic pressure in the balloon is basically balanced with the hydraulic pressure in the channel pipe, avoiding excessive pressure difference between the fracturing pipe and the packer during fracturing, which affects the sealing effect of the packer. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the structure of the hydraulic fracturing assembly in the present invention;

[0032] Figure 3 It is a schematic diagram of the internal structure of the packer in the present invention;

[0033] Figure 4 This is a schematic diagram of the channel tube structure of the present invention;

[0034] Figure 5 This is a schematic diagram of the internal structure of the fracturing pipe in the present invention;

[0035] Figure 6 This is a schematic diagram of the structure of the fracturing pipe in the present invention;

[0036] Figure 7 It is a structural diagram of the balancing valve in the present invention.

[0037] In the figure: 100, surface assembly; 110, directional drilling rig; 120, pressure sensor 1; 130, pressure sensor 2; 140, pressure relief valve; 150, water pipe; 151, valve 1; 160, fracturing fluid pipe; 161, valve 2; 170, high-pressure pump; 180, drilling visualization imager; 190, recorder; 200, hydraulic fracturing assembly; 210, high-pressure steel pipe; 220, packer; 221, channel pipe; 222, balloon; 223, video line 1; 224, data Line adapter; 225, water channel adapter; 230, fracturing pipe; 231, water outlet; 232, partition plate; 233, rotary port; 234, driving paddle; 235, rotary roller; 236, shielding blade; 237, fixing seat; 240, video line 2; 250, unit hose; 260, visualization camera; 270, balancing valve; 271, fixing pipe; 272, connecting pipe; 273, plug shaft; 274, liquid outlet pipe; 275, valve head; 276, slide; 277, return spring. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] See also Figures 1 to 5In an embodiment of the present invention, a long-distance directional drilling multi-stage hydraulic fracturing visualization device is provided for use in underground coal mines. The device includes a surface assembly 100 and a hydraulic fracturing assembly 200. The hydraulic fracturing assembly 200 includes a high-pressure steel pipe 210, a packer 220, a fracturing pipe 230, a video cable 240, a unit hose 250, and a visualization camera 260. The high-pressure steel pipe 210 can be freely assembled and combined in length according to the length of the construction borehole to meet hydraulic fracturing operations under various conditions. The packer 220 is used to expand and contract under the action of water pressure and is used to seal the borehole. The fracturing pipe 230 is used to be installed between two packers 220. A plurality of water outlets 231 are provided on the fracturing pipe 230. The plurality of packers 220 and the fracturing pipe 230 can be freely combined and connected according to the construction conditions to realize hydraulic fracturing of different sections at the same time. The visual camera 260 is used to collect images inside the borehole. The video line 240 is used to connect with the packer 220 to provide power for the visual camera 260 in the borehole and transmit the collected images to the computer. The unit hose 250 is used to connect adjacent packers 220. The ground assembly 100 includes a fixed The directional drilling rig 110, the high-pressure pump 170 and the borehole visualization imager 180 are used to move the entire hydraulic fracturing assembly 200 in the borehole. The high-pressure pump 170 is used to pump the fracturing fluid and control the expansion and contraction of the packer 220. The borehole visualization imager 180 is connected to the visualization camera 260 through the video line 240 to display the image of the surrounding rock inside the borehole. The output end of the high-pressure pump 170 is connected to the water pipe 150 and the fracturing fluid pipe 160. The fracturing fluid pipe 160 is used to communicate with the high-pressure steel pipe 210. The water pipe 150 can communicate with the hydraulic pipe 210. The unit hose 250 is connected, a valve 151 is installed on the water pipe 150, a valve 2 161 is installed on the fracturing fluid pipe 160, a pressure relief valve 140 is installed on the water pipe 150, a pressure sensor 120 is installed on the water pipe 150, a pressure sensor 2 130 is installed on the fracturing fluid pipe 160, a recorder 190 is provided on one side of the pressure sensor 120, and data is connected between the recorder 190 and the pressure sensor 120 and the pressure sensor 2 130. The recorder 190 is used to record the internal pressure conditions of the packer 220 and the fracturing pipe 230 in real time.

[0040] Specifically, multiple packers 220 and fracturing pipes 230 are assembled and installed on the top of the high-pressure steel pipe 210, and the pressure test is checked. According to the number of designed fracturing sections, multiple fracturing pipes 230 are assembled through the high-pressure steel pipe 210 and the packers 220. The video line 240 and the unit hose 250 are connected between two adjacent packers 220. The connection between the high-pressure pump 170 and the water pipe 150 and the fracturing fluid pipe 160 is checked. After the inspection is completed, the water pipe 150 is connected to the unit hose 250. Multiple packers 220 are connected, and the fracturing fluid pipe 160 is connected to the high-pressure steel pipe 210. The hydraulic fracturing assembly 200 is placed in the borehole. The cracks on the inner wall of the borehole are observed through the visual camera 260. The crack development and rock property changes near the fracturing position are observed, and the fracturing position is adjusted to ensure the fracturing effect. Generally, a position with less crack development and a single rock property is selected. When multiple fracturing pipes 230 arrive in place, first open valve 151, start the high-pressure pump 170, and then press the single The flexible pipe 250 is used to inject low-pressure water into the multiple packers 220, so that the packers 220 expand until they are in contact with the hole wall and fixed, so that a closed space is formed between two adjacent packers 220. Then, the valve 151 is closed and the valve 2 161 is opened. The high-pressure pump 170 injects high-pressure water into the fracturing pipe 230. The fracturing fluid flows out of the fracturing pipe 230 through the high-pressure pump 170, the fracturing fluid pipe 160, and the high-pressure steel pipe 210. The liquid pressure during fracturing is recorded by the recorder 190. The pressure is continuously increased and recorded. Record the pressure changes of the fracturing fluid and the on-site conditions during the fracturing process. After a certain period of fracturing, close valve 2 161, turn off the high-pressure pump 170, open the pressure relief valve 140 to slowly release the pressure, so that the packer 220 releases the seal on the borehole, and the fracturing fluid flows out naturally along the borehole. After the pressure is completely relieved, close the pressure relief valve 140, disconnect the fracturing fluid pipe 160 from the high-pressure steel pipe 210, adjust the position of the packer 220 and the fracturing pipe 230 again, and process the next fracturing position in the borehole.

[0041] Example 1

[0042] like Figures 4 and 5As shown, in this embodiment, the packer 220 includes a channel tube 221, and both ends of the channel tube 221 and both ends of the fracturing tube 230 are provided with threaded interfaces, and the fracturing tube 230 can be screwed together with the channel tube 221. A balloon 222 is installed on the channel tube 221, and both ends of the channel tube 221 are provided with a data line adapter 224. A video line 1 223 is fixedly installed between the two data line adapters 224. The data line adapter 224 is used to connect with the video line 240. Both ends of the channel tube 221 are provided with a waterway adapter 225, and the waterway adapter 225 is used to connect with the unit hose 25. 0 are docked together, and multiple water outlets 231 on the fracturing tube 230 are divided into two rows and are respectively arranged on both sides of the fracturing tube 230. A driving paddle 234 is provided inside one end of the fracturing tube 230, and both ends of the driving paddle 234 are rotatably connected to a fixing seat 237, which is fixedly installed between the fixing seat 237 and the inner wall of the fracturing tube 230, and a rotating roller 235 is fixedly installed at one end of the driving paddle 234. The rotating roller 235 includes three annular shielding blades 236 arranged at equal angles. The shielding blades 236 are used to shield the water outlet 231, and a gap is provided between the shielding blades 236 and the inner wall of the fracturing tube 230.

[0043] In this embodiment, when the hydraulic fracturing assembly 200 is moved upward, since the inner wall of the borehole is not smooth and has cracks or fractures, the packer 220 is easily stuck with the inner wall of the borehole when it moves upward. Therefore, by setting the driving paddle 234 and the rotating roller 235, when the height position of the hydraulic fracturing assembly 200 is adjusted, the high-pressure pump 170 injects low-pressure liquid into the high-pressure steel pipe 210 through the fracturing liquid pipe 160, and when the liquid passes through the driving paddle 234 from bottom to top in the fracturing pipe 230, it drives the driving paddle 234 to rotate. 4 rotates, the driving paddle 234 drives the rotating roller 235 to rotate, and the multiple shielding blades 236 on the rotating roller 235 are set to open the water outlets 231 on both sides of the fracturing tube 230 in turn, so that the liquid is sprayed out from both sides of the fracturing tube 230 in turn, thereby driving the top of the hydraulic fracturing assembly 200 to shake left and right, thereby preventing the top of the hydraulic fracturing assembly 200 from being stuck with the hole wall. At this time, the packer 220 is in a contracted state, and the liquid is sprayed out of the fracturing tube 230 and discharged naturally along the drilled hole.

[0044] like Figure 5 As shown, in this embodiment, a partition plate 232 is fixedly installed on the inner wall of the other end of the fracturing tube 230 , and a revolving opening 233 is opened on the outer wall of the other end of the fracturing tube 230 .

[0045] During specific implementation, there are two types of fracturing tubes 230, namely Type A and Type B. The interior of the Type A fracturing tube 230 is provided with a driving paddle 234 and a rotating roller 235, and the Type B fracturing tube 230 is only provided with multiple water outlets 231. When assembled and installed, there is only one Type A fracturing tube 230, and the remaining fracturing tubes 230 are all Type B. The Type A fracturing tube 230 is installed at the position closest to the high-pressure steel pipe 210. Through the setting of the partition plate 232, the liquid will be completely ejected from the water outlet 231 when passing through the Type A fracturing tube 230, avoiding the liquid directly flowing up from the inside of the fracturing tube 230 to other fracturing tubes 230, and sharing the pressure of the water ejected from the water outlet 231, thereby facilitating the water jet to drive the top of the hydraulic fracturing assembly 200 to swing.

[0046] Example 2

[0047] like Figures 5 to 7 As shown, in this embodiment, a balancing valve component 270 is installed on one side of the channel tube 221. The balancing valve component 270 is used to balance the pressure inside the packer 220 and the fracturing tube 230. The balancing valve component 270 includes a fixed tube 271, and an insert shaft 273 is slidably inserted into the fixed tube 271. One end of the insert shaft 273 is fixedly installed with the inner wall of the balloon 222. A connecting tube 272 is installed between one end of the fixed tube 271 and the channel tube 221. The outer wall of the other end of the fixed tube 271 is fixedly connected to a liquid outlet pipe 274. The outer wall of the liquid outlet pipe 274 is fixedly connected to a slide 276. A valve head 275 is slidably connected to the slide 276. One end of the valve head 275 is slidably inserted into the liquid outlet pipe 274, and a return spring 277 is fixedly installed between the other end of the valve head 275 and the slide 276.

[0048] In the specific implementation, initially, the balloon 222 is in a contracted state, at which time the plug shaft 273 closes one end of the connecting pipe 272, and then during the height adjustment process of the hydraulic fracturing assembly 200, when the high-pressure pump 170 injects pressure into the channel pipe 221, the liquid cannot enter the balloon 222. When pressure is injected into the balloon 222 through the unit hose 250, the balloon 222 expands. At this time, the liquid outlet pipe 274 and the valve head 275 cooperate to form a one-way valve, thereby avoiding pressure loss in the balloon 222, making the balloon 222 expands to seal the borehole, and at this time the plug shaft 273 releases the blockage on one end of the connecting pipe 272. When the pressure in the channel pipe 221 gradually rises and the water pressure in the channel pipe 221 is higher than the water pressure in the packer 220, the liquid in the channel pipe 221 pushes open the valve head 275 and enters the balloon 222, so that the hydraulic pressure in the balloon 222 is basically balanced with the hydraulic pressure in the channel pipe 221, avoiding excessive pressure difference between the fracturing pipe 230 and the packer 220 during fracturing, which affects the sealing effect of the packer 220.

[0049] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0050] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A long-distance directional drilling multi-stage hydraulic fracturing visualization device for underground coal mines, characterized in that: The invention comprises a surface assembly (100) and a hydraulic fracturing assembly (200), wherein the hydraulic fracturing assembly (200) comprises: The high-pressure steel pipe (210) can be freely assembled and combined in length according to the length of the construction drilling hole, so as to meet the hydraulic fracturing construction operations under various conditions; a packer (220) configured to expand and contract under water pressure, the packer (220) being configured to seal the borehole; A fracturing pipe (230) is installed between two packers (220). The fracturing pipe (230) is provided with a plurality of water outlets (231). The plurality of packers (220) and the fracturing pipe (230) can be freely combined and connected according to construction conditions to achieve simultaneous hydraulic fracturing of different sections. A visual camera (260) collects images of the interior of the borehole; Video cable 2 (240), connected to the packer (220), provides power to the visualization camera (260) in the borehole, and transmits the collected images to the computer; A unit hose (250) is used to connect adjacent packers (220); The multiple water outlets (231) on the fracturing pipe (230) are divided into two rows and are respectively arranged on both sides of the fracturing pipe (230); a driving paddle (234) is provided inside one end of the fracturing pipe (230); both ends of the driving paddle (234) are rotatably connected to fixed seats (237); the fixed seats (237) are fixedly installed between the inner wall of the fracturing pipe (230); a rotating roller (235) is fixedly installed at one end of the driving paddle (234); the rotating roller (235) includes three annular shielding blades (236) arranged at equal angles; the shielding blades (236) are used to shield the water outlets (231); A gap is provided between the shielding blade (236) and the inner wall of the fracturing tube (230); A partition plate (232) is fixedly mounted on the inner wall of the other end of the fracturing tube (230), and a revolving opening (233) is provided on the outer wall of the other end of the fracturing tube (230).

2. The device for visualizing long-distance directional drilling and multi-stage hydraulic fracturing in underground coal mines according to claim 1, characterized in that: The surface assembly (100) includes a directional drill (110), a high-pressure pump (170) and a borehole visualization imager (180). The directional drill (110) is used to move the entire hydraulic fracturing assembly (200) in the borehole. The high-pressure pump (170) is used to pump fracturing fluid and control the expansion and contraction of the packer (220). The borehole visualization imager (180) is connected to a visualization camera (260) via a video line 2 (240) and is used to display the inner periphery of the borehole. The rock image is shown. A water pipe (150) and a fracturing fluid pipe (160) are connected and installed on the output end of the high-pressure pump (170). The fracturing fluid pipe (160) is used to communicate with the high-pressure steel pipe (210). The water pipe (150) can be connected with the unit hose (250). A valve 1 (151) is installed on the water pipe (150). A valve 2 (161) is installed on the fracturing fluid pipe (160). A pressure relief valve (140) is connected and installed on the water pipe (150).

3. The device for visualizing long-distance directional drilling and multi-stage hydraulic fracturing in underground coal mines according to claim 2, characterized in that: A pressure sensor 1 (120) is installed on the water pipe (150), and a pressure sensor 2 (130) is installed on the fracturing fluid pipe (160). A recorder (190) is provided on one side of the pressure sensor 1 (120). The recorder (190) is data-connected with the pressure sensor 1 (120) and the pressure sensor 2 (130). The recorder (190) is used to record the internal pressure conditions of the packer (220) and the fracturing pipe (230) in real time.

4. The device for visualizing long-distance directional drilling and multi-stage hydraulic fracturing in underground coal mines according to claim 1, characterized in that: The packer (220) comprises a channel tube (221), both ends of the channel tube (221) and both ends of the fracturing tube (230) are provided with threaded interfaces, the fracturing tube (230) can be screwed together with the channel tube (221), a balloon (222) is installed on the channel tube (221), both ends of the channel tube (221) are provided with data line transfer interfaces (224), a video line 1 (223) is fixedly installed between the two data line transfer interfaces (224), the data line transfer interface (224) is used for docking with video line 2 (240), and both ends of the channel tube (221) are provided with waterway transfer interfaces (225), the waterway transfer interface (225) is used for docking with the unit hose (250).

5. A visualization device for long-distance directional drilling and multi-stage hydraulic fracturing in underground coal mines according to any one of claim 4, characterized in that: A balancing valve component (270) is installed on one side of the channel pipe (221), and the balancing valve component (270) is used to balance the pressure inside the packer (220) and the fracturing pipe (230).

6. The device for visualizing long-distance directional drilling and multi-stage hydraulic fracturing in underground coal mines according to claim 5, characterized in that: The balancing valve component (270) includes a fixed tube (271), an insert shaft (273) is slidably inserted into the fixed tube (271), one end of the insert shaft (273) is fixedly installed with the inner wall of the balloon (222), a connecting tube (272) is installed between one end of the fixed tube (271) and the channel tube (221), and a liquid outlet tube (274) is fixedly connected to the outer wall of the other end of the fixed tube (271).

7. The device for visualizing long-distance directional drilling and multi-stage hydraulic fracturing in underground coal mines according to claim 6, characterized in that: The outer wall of the liquid outlet pipe (274) is fixedly connected with a slide (276), and a valve head (275) is slidably connected to the slide (276). One end of the valve head (275) is slidably plugged into the liquid outlet pipe (274), and a return spring (277) is fixedly installed between the other end of the valve head (275) and the slide (276).

Images