Directional long drill hole hydraulic fracturing method for underground long-distance high-pressure pump set

Abstract

The invention discloses an underground long-distance high-pressure pump set directional long drilling hydraulic fracturing method which comprises the following steps: S1, mounting a high-pressure pump set in an underground central water sump, and debugging; s2, a route is laid, and a three-way ball valve is installed; s3, a directional fracturing drill hole is designed and constructed, and a channel is provided for fracturing operation; s4, a fracturing tool is selected and installed in the drill hole, and a high-pressure pipeline is connected; s5, staged fracturing is conducted on the drilled hole, and fracturing parameters are monitored in real time; s6, monitoring data in the fracturing process are collected, the fracturing effect is evaluated, whether the expected target is reached or not is judged, and re-fracturing is conducted if the expected target is not reached; and S7, after fracturing operation is completed, the high-pressure pipeline is recycled, equipment maintenance is conducted, and it is ensured that the equipment is intact and free of damage for subsequent use. The high-pressure pump set is arranged in the central water sump, long-distance liquid supply is achieved through accumulated water in the water sump, the problem of insufficient liquid amount is solved, the fracturing efficiency is improved, and the fracturing effect is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mine resource development, and particularly to a method for directional long-hole hydraulic fracturing of a long-distance high-pressure pump set underground. Background Art

[0002] At present, directional hydraulic fracturing technology is commonly used in aspects such as prevention and control of coal mine rock bursts and gas drainage, and has become the core support for the "disaster control - safety guarantee - efficient production" chain in coal mines. There are currently a ground "L"-type horizontal well fracturing system and an underground directional long-hole hydraulic fracturing system, and both systems have their advantages and disadvantages. Although the ground "L"-type horizontal well fracturing in coal mines can achieve large-scale fracturing, it has significant disadvantages such as a complex system, high drilling costs, complex coordination of ground land use, difficult construction in special terrains, limited supply of ground water sources, etc., and it is only applicable to unmined areas underground, with poor flexibility and economy; although the underground directional long-hole hydraulic fracturing has lower costs and higher flexibility, it also has core defects: limited by the underground space, the power and water supply of the fracturing pump set are small, resulting in limited injection pressure of the fracturing fluid and small fracture propagation scale, frequent disassembly and movement of the pump set for different borehole positions, complex operation, low construction efficiency, and more prominent stability risks and safety hazards of high-pressure operation equipment in narrow roadways, and generally it is difficult to meet the requirements of efficient fracturing of underground directional long holes in coal mines.

[0003] Based on the above technical problems, the present invention provides a method for directional long-hole hydraulic fracturing of a long-distance high-pressure pump set underground. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for directional long-hole hydraulic fracturing of a long-distance high-pressure pump set underground to solve the problems existing in the prior art.

[0005] To achieve the above purpose, the present invention provides the following solution: The present invention provides a method for directional long-hole hydraulic fracturing of a long-distance high-pressure pump set underground, including the following steps: S1, Install a high-pressure pump set in the underground central sump and conduct debugging to ensure the stable operation of the pump set and provide a stable high-pressure water source for subsequent fracturing operations; S2, Plan the laying route of the high-pressure water inlet pipeline according to the fracturing operation location and install a three-way ball valve to control the flow direction and pressure of the fracturing fluid; S3, Design and construct a directional fracturing borehole to ensure that the borehole trajectory meets the design requirements and provide a channel for fracturing operations; S4, Select a fracturing tool and install it into the borehole, connect it to the high-pressure pipeline, and realize the connection between the fracturing tool and the high-pressure pump set; S5, Conduct segmented fracturing on the borehole, monitor the fracturing parameters in real time, and adjust the fracturing strategy according to the monitoring data to ensure the fracturing effect; S6. Collect the monitoring data during the fracturing process, evaluate the fracturing effect, and determine whether the expected goal is achieved. If the expected goal is not achieved, perform repeated fracturing. S7. After the fracturing operation is completed, recover the high-pressure pipeline and perform equipment maintenance to ensure that the equipment is intact for subsequent use.

[0006] According to the downhole long-distance high-pressure pump unit directional long borehole hydraulic fracturing method provided by the present invention, S1 includes the following steps: S11. Considering factors such as downhole space, convenience of water source acquisition, and convenience of pump unit maintenance, select the installation point of the high-pressure pump unit near the downhole central sump. S12. Clean and level the selected position to ensure there is enough space and a stable support surface for the installation and fixation of the pump unit. S13. Install the high-pressure water pump, motor, and control system components step by step according to the construction sequence, ensuring that the connections of all components are tight and there is no leakage. S14. Connect the power supply and check whether the electrical connection is correct to ensure there is no short circuit or leakage. S15. Start the pump unit and perform no-load and load commissioning, monitor the output pressure and flow parameters of the pump unit to ensure that the pump unit operates stably and has reliable performance.

[0007] According to the downhole long-distance high-pressure pump unit directional long borehole hydraulic fracturing method provided by the present invention, S2 includes the following steps: S21. According to the fracturing operation location and downhole system layout, plan the laying route of the high-pressure water inlet pipeline to ensure the shortest pipeline connection and the least resistance. S22. Lay the high-pressure water inlet pipeline along the planned route, and use clamps and brackets to fix the pipeline to ensure that the pipeline connection is tight and there is no leakage. S23. Install three-way ball valves on the pipeline according to the fracturing requirements to ensure that the valves are firmly installed and operate flexibly, facilitating adjustment and control during subsequent fracturing operations. S24. Conduct a pressure test on the laid pipeline to ensure that the pipeline can withstand the design pressure and there is no leakage.

[0008] According to the downhole long-distance high-pressure pump unit directional long borehole hydraulic fracturing method provided by the present invention, S3 includes the following steps: S31. According to the fracturing requirements, on-site conditions, and geological data, design the parameters of the directional fracturing borehole, including borehole depth, diameter, inclination angle, and azimuth angle. S31. Use measuring instruments to determine the starting position and direction of the borehole to ensure that the borehole trajectory meets the design requirements. S31. Use a directional drilling rig to conduct borehole construction, and monitor the borehole parameters in real time, including depth, inclination angle, and azimuth angle, to ensure the borehole quality. Drilling cleaning: After the drilling construction is completed, clean the cuttings and debris in the drill hole to ensure that the drill hole is unobstructed.

[0009] According to the downhole long-distance high-pressure pump unit directional long drill hole hydraulic fracturing method provided by the present invention, S4 includes the following steps: S41: Select fracturing tools according to fracturing requirements and drilling parameters. S42: Inspect and test the fracturing tools to ensure their reliable performance and flexible operation. S43: Install the fracturing tools into the drill hole to ensure accurate tool position and firm connection. S44: Connect the fracturing tools to the three-way ball valve using high-pressure rubber hoses to achieve the connection between the fracturing tools and the high-pressure pump unit, and ensure tight connection and no leakage.

[0010] According to the downhole long-distance high-pressure pump unit directional long drill hole hydraulic fracturing method provided by the present invention, S5 includes the following steps: S51: Check the connection of the fracturing tools, high-pressure pump unit and pipelines to ensure no abnormalities; prepare fracturing fluid and check whether its performance meets the requirements. S52: Open the three-way ball valve and the high-pressure pump unit in sequence to start sectional fracturing of the drill hole. S53: Monitor the fracturing parameters in real time during fracturing, including pressure, flow rate, injection volume, to ensure that the fracturing operation is carried out within a safe range. S54: Evaluate the fracturing effect according to the monitoring data, adjust the output pressure and flow rate of the high-pressure pump unit according to the fracturing effect, optimize the fracturing strategy, and ensure that the fracturing effect reaches the expected goal.

[0011] According to the downhole long-distance high-pressure pump unit directional long drill hole hydraulic fracturing method provided by the present invention, S6 includes the following steps: S61: During fracturing, collect the monitoring data of the pressure, flow rate, injection volume of the fracturing fluid, as well as the microseismic monitoring, anchor cable stress monitoring, hydraulic support force monitoring and roadway surface displacement monitoring data. S62: Evaluate the fracturing effect according to the collected data and on-site observations, including the crack propagation situation and the fracturing fluid distribution situation. S63: Judge whether the fracturing operation reaches the expected goal, such as the weakening degree of the roof rock stratum and the coal body pressure relief effect. S64: If the expected goal is not achieved, analyze the reasons and adjust the fracturing strategy, and carry out repeated fracturing operations until the expected effect is achieved.

[0012] According to the downhole long-distance high-pressure pump unit directional long drill hole hydraulic fracturing method provided by the present invention, S7 includes the following steps: S71. When the fracturing of the overlying strata in the working face is completed or the fracturing in the main roadway area is completed, recover the high-pressure water inlet pipeline according to the recovery plan; inspect and maintain the recovered pipeline, clean the dirt and debris inside the pipeline to ensure that the pipeline is intact; S72. Maintain and service the high-pressure pump unit and fracturing tool equipment, check the sealing performance, lubrication condition, and electrical connection of the equipment to ensure reliable equipment performance and flexible operation; S73. Sort out the records and data during the fracturing operation, file and analyze them to provide reference for subsequent fracturing operations.

[0013] The present invention discloses the following technical effects: 1) The present invention can pre-crack and weaken the hard roof, reduce the risk of rock burst, and can also be used for coal body pressure relief to release the stress of coal body in the high-stress area. In addition, in the hydraulic fracturing of high-gas coal seams, it can improve the gas permeability of the coal seam, achieve gas permeability enhancement, and efficiently extract gas.

[0014] 2) The high-pressure pump unit of the present invention is arranged in the central sump, and the accumulated water in the sump is used for long-distance liquid supply to solve the problem of insufficient liquid volume, improve the fracturing efficiency, ensure the fracturing effect, and directly use the accumulated water in the sump to achieve "zero discharge", which conforms to the concept of green mining; there is no need to arrange high-pressure pump units, water tanks and other equipment at other locations in the mine, avoiding the repeated movement of the pump unit, improving the efficiency, and the high-pressure water pump unit works in a spacious space, reducing the safety risk.

[0015] 3) The present invention flexibly plans the laying route of the high-pressure water inlet pipeline according to the fracturing operation location and installs a three-way ball valve to control the flow direction and pressure of the fracturing fluid. This design enables the fracturing process to be adjusted according to actual needs, enhances the flexibility and controllability of the fracturing operation, and helps to achieve a more precise fracturing effect.

[0016] 4) The present invention designs and constructs directional fracturing boreholes to ensure that the borehole trajectory meets the design requirements, providing a channel for the fracturing operation. At the same time, the fracturing tool is connected to the high-pressure pipeline to achieve the optimal connection between the fracturing tool and the high-pressure pump unit. These measures help to optimize the fracturing effect, improve the resource utilization rate, and reduce unnecessary waste.

[0017] 5) After the fracturing operation of the present invention is completed, by recovering the high-pressure pipeline and maintaining the equipment, the equipment is ensured to be intact and convenient for subsequent use. This method not only reduces resource waste and environmental pollution, but also reduces the equipment maintenance cost. At the same time, by scientifically evaluating the fracturing effect and performing repeated fracturing when necessary, the safety and effectiveness of the operation are further guaranteed, and the potential risks caused by fracturing failure are reduced. Description of the Drawings

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0019] Figure 1 This is a flowchart of the directional long - hole hydraulic fracturing method for the downhole long - distance high - pressure pump unit of the present invention. Detailed implementation manners

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0021] To make the above - mentioned objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners.

[0022] Refer to Figure 1 , the present invention provides a directional long - hole hydraulic fracturing method for a downhole long - distance high - pressure pump unit, including the following steps: S1. Excavate a chamber in the existing space or adjacent location near the underground central sump, arrange a high - pressure pump unit, and conduct debugging to ensure the stable operation of the pump unit, providing a stable high - pressure water source for subsequent fracturing operations. S2. Plan the laying route of the high - pressure water inlet pipeline according to the fracturing operation location and install a three - way ball valve to control the flow direction and pressure of the fracturing fluid. S3. Design and construct a directional fracturing hole to ensure that the hole trajectory meets the design requirements. Rock overburden exploration and rock physical and mechanical property determination can be carried out every 200 - 500 m in the fracturing area to determine and optimize the fracturing horizon, providing an operation channel for fracturing operations. S4. Select a matching fracturing tool according to the hole diameter and install it into the hole. After the packer expands, its diameter is at least 12 mm larger than the hole diameter, connect it to the high - pressure pipeline to achieve the connection between the fracturing tool and the high - pressure pump unit, and conduct a hole - sealing pressure - maintaining test before formal fracturing. S5. Conduct segmented fracturing on the hole, monitor the fracturing parameters in real time, and adjust the fracturing strategy according to the monitoring data to ensure the fracturing effect. S6. Collect the monitoring data during the fracturing process, evaluate the fracturing effect, and judge whether the expected goal is achieved. If the expected goal is not achieved, repeated fracturing is carried out. After the fracturing operation in S7, the high-pressure pipeline is recovered and the equipment is maintained to ensure that the equipment is intact for subsequent use.

[0023] For the further optimized plan, S1 includes the following steps: S11: Selection of installation point; Device selection: According to factors such as the underground space, convenience of water source acquisition, and convenience of pump unit maintenance, select a position near the underground central sump with sufficient space and a stable support surface as the installation point of the high-pressure pump unit; Construction parameters: The installation point should be far from the area directly scoured by the water source to ensure the firmness of the pump unit foundation and the bearing capacity meets the operation requirements of the pump unit; S12: Site cleaning and leveling; Device selection: Use cleaning equipment (such as a sweeper and a forklift) to clean and level the selected position; Construction parameters: After cleaning, the site should be free of debris and water accumulation, and the flatness error does not exceed ±50 mm to ensure the stable installation of the pump unit; S13: Component installation; Device selection: According to the model of the high-pressure pump unit and the construction sequence, gradually install the high-pressure water pump, motor, and control system components; Construction parameters: Ensure that the connections of all components are tight and there is no leakage, and the bolt tightening torque should meet the requirements of the equipment instruction manual; S14: Electrical connection; Device selection: Use cables and connectors that meet the coal mine safety standards for electrical connection; Construction parameters: The electrical connection should be carried out according to the equipment wiring diagram to ensure no short circuit or leakage, and the grounding resistance should be less than 4 ohms; S15: Pump unit commissioning; Device selection: Use commissioning equipment to conduct no-load and load commissioning on the pump unit; Construction parameters: During the commissioning process, parameters such as the output pressure and flow rate of the pump unit need to be monitored to ensure the stable operation and reliable performance of the pump unit, and the output pressure fluctuation does not exceed ±5%;

[0024] For the further optimized plan, S2 includes the following steps: S21: Laying route planning; Device selection: According to the fracturing operation location and the underground system layout, use 3D modeling software to plan the laying route of the high-pressure water inlet pipeline; Construction parameters: The laying route needs to consider parameters such as the turning radius of the roadway and the pipeline slope to ensure the shortest pipeline connection and the smallest resistance, and the turning radius is not less than 5 times the pipeline diameter; S22: Pipeline laying and fixing; Device selection: Select pipeline materials that are resistant to high pressure and corrosion, and use fixtures and brackets for laying and fixing; Construction parameters: When laying the pipeline, it should be kept horizontal or conform to the designed gradient. Use a level and a gradient gauge for monitoring to ensure that the pipeline connections are tight and leak-free, and the spacing between fixing points does not exceed 3 meters; S23: Installation of three-way ball valve; Device selection: Select a three-way ball valve with high pressure and high sealing performance, and install it on the pipeline near the target working face according to the fracturing requirements; Construction parameters: The spacing between ball valves should consider the fracturing operation efficiency and operation convenience, generally not exceeding 50 meters. After installation, a sealing test should be carried out; S24: Pressure test; Device selection: After the conveying tool string is completed, start the pump group to inject water at a low gear to promote the expansion and setting of the packer. Slowly close the three-way drain valve, and then observe the change of the pressure on the high-pressure gauge. When the pressure reaches the designed pressure, close the high-pressure valve for pressure holding. After stopping the pump for 20 minutes, there is no dripping at the orifice and the hole wall, and the pressure does not drop, and the pressure test is over; Construction parameters: The test pressure should reach 1.5 times the designed pressure, and the test time should be kept not less than 30 minutes to ensure that there is no leakage in the pipeline.

[0025] Further optimize the plan. S3 includes the following steps: S31: Drilling parameter design; Device selection: Use geological exploration instruments and drilling design software for drilling parameter design; Construction parameters: According to the fracturing requirements and geological conditions, design the drilling depth to be 300 - 900 meters, the drilling diameter to be 75 - 150 millimeters, and the dip angle and azimuth angle to be adjusted according to the specific geological conditions; S32: Determination of the starting position and direction of drilling; Device selection: Use a total station or a GPS locator to determine the starting position and direction of drilling; Construction parameters: The error of the starting position of drilling does not exceed ±0.1 meter, and the direction error does not exceed ±1 degree; S33: Drilling construction; Device selection: Use a directional drilling rig for drilling construction. The drilling rig should have a high-precision guidance system and an automatic deviation correction function; Construction parameters: Monitor the drilling parameters in real time, including depth, dip angle, and azimuth angle, to ensure the drilling quality; The drilling speed is adjusted according to the rock formation hardness. The drilling speed for a hard roof generally does not exceed 5 meters per hour; S34: Drilling cleaning; Device selection: Use high-pressure air or water for drilling cleaning; Construction parameters: The cleaning time is adjusted according to the drilling depth and the amount of cuttings, generally not less than 30 minutes, to ensure unobstructed drilling.

[0026] To further optimize the plan, S4 includes the following steps: S41: Selection of fracturing tools; Device selection: According to the fracturing requirements and drilling parameters, select fracturing tools such as packers, sandblasters, etc.; Construction parameters: The fracturing tools need to have high pressure and high wear resistance to ensure no damage during the fracturing process; S42: Inspection and testing of fracturing tools; Device selection: Use testing equipment to inspect and test the fracturing tools; Construction parameters: During the testing process, actual fracturing conditions need to be simulated to ensure reliable performance and flexible operation of the fracturing tools; S43: Installation of fracturing tools; Device selection: Use installation equipment to install the fracturing tools into the borehole; Construction parameters: During the installation process, ensure accurate tool position and firm connection, and use a locator for positioning; S44: Connection of fracturing tools; Device selection: Use a high-pressure hose to connect the fracturing tools to the three-way ball valve; Construction parameters: During the connection process, ensure tight connection and no leakage, and use a sealing ring for sealing.

[0027] To further optimize the plan, S5 includes the following steps: S51: Fracturing preparation; Device selection: Check the connection of the fracturing tools, high-pressure pump unit and pipeline, and prepare the fracturing fluid; Construction parameters: The fracturing fluid needs to meet the design requirements, such as viscosity, density, etc., to ensure no impurities; S52: Start fracturing; Device selection: Open the three-way ball valve and the high-pressure pump unit in sequence to start sectional fracturing of the borehole; Construction parameters: During the fracturing process, maintain stable pressure and flow rate to avoid excessive pressure fluctuations affecting the fracturing effect; S53: Real-time monitoring; Device selection: Use monitoring instruments to real-time monitor fracturing parameters, including pressure, flow rate, injection volume, etc.; Construction parameters: The monitoring data needs to be recorded and analyzed in real-time to ensure that the fracturing operation is carried out within a safe range; S54: Adjust the fracturing strategy; Device selection: Evaluate the fracturing effect according to the monitoring data, and adjust the output pressure and flow rate of the high-pressure pump unit according to the fracturing effect; Construction parameters: Optimize the fracturing strategy to ensure that the fracturing effect meets the expected goals, such as fracture propagation length, width, etc.

[0028] Further optimize the plan. S6 includes the following steps: S61: Data collection; Device selection: Collect monitoring data on the pressure, flow rate, injection volume of the fracturing fluid, as well as data such as microseismic monitoring, anchor cable stress monitoring, hydraulic support force monitoring, and roadway surface displacement monitoring. Construction parameters: The data collected should be comprehensive and accurate to ensure the reliability of the evaluation results. S62: Fracturing effect evaluation; Device selection: Evaluate the fracturing effect based on the collected data and on-site observations, including fracture propagation and fracturing fluid distribution. Construction parameters: The evaluation results should be quantified and specific for subsequent analysis and improvement. S63: Judge the expected goals; Device selection: Judge whether the fracturing operation has achieved the expected goals, such as the weakening degree of the roof rock formation and the coal body pressure relief effect. Construction parameters: The expected goals should be clear and specific for subsequent adjustment and optimization. S64: Repeated fracturing; Device selection: If the expected goals are not achieved, analyze the reasons and adjust the fracturing strategy for repeated fracturing operations. Construction parameters: During repeated fracturing, adjust the fracturing parameters and strategy according to the actual situation to ensure the expected effect is achieved.

[0029] Further optimize the plan. S7 includes the following steps: Device selection: When the overlying rock fracturing of the working face is completed or the fracturing of the main roadway area is completed, recover the high-pressure water inlet pipeline according to the recovery plan. Construction parameters: During the recovery process, keep the pipeline clean, avoid damage and deformation, and number and store it after recovery. S72: Equipment maintenance Device selection: Maintain and service equipment such as high-pressure pump units and fracturing tools. Construction parameters: Check the sealing performance, lubrication condition, electrical connection, etc. of the equipment, replace damaged parts and worn seals to ensure reliable equipment performance and flexible operation. S73: Data archiving and analysis Device selection: Organize the records and data during the fracturing operation for archiving and analysis. Construction parameters: The archived data should be comprehensive and accurate to provide reference for subsequent fracturing operations. During the analysis process, use analysis software for data processing and analysis.

[0030] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0031] The embodiments described above are only for describing the preferred mode of the present invention, rather than limiting the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solution of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A directional long - hole hydraulic fracturing method for downhole long - distance high - pressure pump sets, characterized in that It includes the following steps: S1. Install a high-pressure pump unit in the underground central sump and commission it to ensure stable operation of the pump unit, providing a stable high-pressure water source for subsequent fracturing operations; S2. Plan the laying route of the high-pressure inlet pipeline according to the fracturing operation location and install a three-way ball valve to control the flow direction and pressure of the fracturing fluid; S3. Design and construct directional fracturing boreholes to ensure that the borehole trajectories meet the design requirements, providing a passage for fracturing operations; S4. Select fracturing tools and install them into the boreholes, connect to the high-pressure pipelines to achieve the connection between the fracturing tools and the high-pressure pump unit; S5. Conduct segmented fracturing on the boreholes, monitor the fracturing parameters in real time, and adjust the fracturing strategy according to the monitoring data to ensure the fracturing effect; S6. Collect the monitoring data during the fracturing process, evaluate the fracturing effect, and determine whether the expected goal is achieved. If the expected goal is not achieved, repeat the fracturing; S7. After the fracturing operation is completed, recover the high-pressure pipelines and conduct equipment maintenance to ensure that the equipment is intact for subsequent use.

2. A directional long - hole hydraulic fracturing method for an underground long - distance high - pressure pump set according to claim 1, characterized in that, S1 includes the following steps: S11. Considering factors such as underground space, convenience of water source acquisition, and ease of pump unit maintenance, select the installation point of the high-pressure pump unit near the underground central sump; S12. Clean and level the selected location to ensure there is enough space and a stable support surface for the installation and fixation of the pump unit; S13. Install the high-pressure water pump, motor, and control system components step by step according to the construction sequence to ensure that the connections between the components are tight and there is no leakage; S14. Connect the power supply and check whether the electrical connection is correct to ensure there is no short circuit or leakage; S15. Start the pump unit and conduct no-load and load commissioning, monitor the output pressure and flow parameters of the pump unit to ensure stable operation and reliable performance of the pump unit.

3. A downhole long-distance high-pressure pump unit directional long borehole hydraulic fracturing method according to claim 1, characterized in that, S2 includes the following steps: S21. Plan the laying route of the high-pressure inlet pipeline according to the fracturing operation location and the underground system layout to ensure the shortest pipeline connection and the least resistance; S22. Lay the high-pressure inlet pipeline along the planned route, fix the pipeline using clamps and brackets to ensure tight connection and no leakage of the pipeline; S23. Install a three-way ball valve on the pipeline according to the fracturing requirements to ensure that the valve is firmly installed and operates flexibly for adjustment and control in subsequent fracturing operations; S24. Conduct a pressure test on the laid pipeline to ensure that the pipeline can withstand the design pressure and there is no leakage.

4. A directional long borehole hydraulic fracturing method for an underground long-distance high-pressure pump unit according to claim 1, characterized in that S3 includes the following steps: S31. Design the parameters of the directional fracturing boreholes, including borehole depth, diameter, inclination angle, and azimuth angle, according to the fracturing requirements, site conditions, and geological data; S31. Use measuring instruments to determine the starting position and direction of the borehole to ensure that the borehole trajectory meets the design requirements; S31. Use a directional drilling rig to conduct borehole construction and monitor the borehole parameters in real time, including depth, inclination angle, and azimuth angle, to ensure the borehole quality; Borehole cleaning. After the borehole construction is completed, clean the cuttings and debris in the borehole to ensure unobstructed boreholes.

5. A downhole long-distance high-pressure pump unit directional long-hole hydraulic fracturing method according to claim 1, characterized in that, S4 includes the following steps: S41. Select fracturing tools according to the fracturing requirements and borehole parameters; S42. Inspect and test the fracturing tools to ensure their reliable performance and flexible operation; S43. Install the fracturing tools into the boreholes to ensure accurate tool position and firm connection; S44. Connect the fracturing tool to the three-way ball valve using a high-pressure rubber hose to achieve the connection between the fracturing tool and the high-pressure pump unit, ensuring a tight connection and no leakage.

6. A method for directional long-hole hydraulic fracturing of an underground long-distance high-pressure pump unit according to claim 1, characterized in that S5 includes the following steps: S51. Check the connection conditions of the fracturing tool, high-pressure pump unit and pipeline to ensure no abnormalities; prepare the fracturing fluid and check whether its performance meets the requirements; S52. Open the three-way ball valve and the high-pressure pump unit in sequence to start the staged fracturing of the borehole; S53. Monitor the fracturing parameters in real time during the fracturing process, including pressure, flow rate and injection volume, to ensure that the fracturing operation is carried out within a safe range; S54. Evaluate the fracturing effect based on the monitoring data, adjust the output pressure and flow rate of the high-pressure pump unit according to the fracturing effect, optimize the fracturing strategy, and ensure that the fracturing effect reaches the expected goal.

7. A method for directional long - hole hydraulic fracturing of an underground long - distance high - pressure pump set according to claim 1, characterized in that, S6 includes the following steps: S61. During the fracturing process, collect the monitoring data of the pressure, flow rate and injection volume of the fracturing fluid, as well as the microseismic monitoring, anchor cable stress monitoring, hydraulic support stress monitoring and roadway surface displacement monitoring data; S62. Evaluate the fracturing effect based on the collected data and on-site observations, including the crack propagation situation and the fracturing fluid distribution situation; S63. Judge whether the fracturing operation has reached the expected goal, such as the weakening degree of the roof rock stratum and the coal body pressure relief effect; S64. If the expected goal is not achieved, analyze the reasons and adjust the fracturing strategy to carry out repeated fracturing operations until the expected effect is achieved.

8. A method for hydraulic fracturing of a directional long borehole of an underground long-distance high-pressure pump set according to claim 1, characterized in that, S7 includes the following steps: S71. When the overlying rock fracturing of the working face is completed or the fracturing of the main roadway area is completed, recover the high-pressure water inlet pipeline according to the recovery plan; check and maintain the recovered pipeline, clean the dirt and debris in the pipeline to ensure that the pipeline is intact; S72. Maintain and service the high-pressure pump unit and fracturing tool equipment, check the sealing performance, lubrication condition and electrical connection of the equipment to ensure reliable equipment performance and flexible operation; S73. Sort out the records and data during the fracturing operation, file and analyze them to provide reference for subsequent fracturing operations.

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