Hard rock fracturing device and method based on electromagnetic induction excitation steam explosion

Abstract

The invention belongs to the technical field of rock mass fracturing, particularly relates to a hard rock fracturing device and method based on electromagnetic induction excitation steam explosion, and solves the problems that a traditional rock fracturing method is high in safety risk, low in energy utilization efficiency, difficult to accurately control the fracture direction, likely to cause environmental pollution and the like. The invention discloses a hard rock fracturing device based on electromagnetic induction excitation steam explosion. The hard rock fracturing device comprises a pressure sealing container, an electromagnetic induction heating system, a high-speed pressure release valve, a sensor unit and a control unit, an upper sealing cover is mounted at the top opening of the pressure sealing container; the electromagnetic induction heating system is mounted on the outer side of the upper part of the pressure sealing container; the high-speed pressure release valves are symmetrically connected to the outer side of the middle lower part of the pressure sealing container and are communicated with the interior of the pressure sealing container; the signal output end of the control unit is communicated with the electromagnetic induction heating system and the control end of the high-speed pressure release valve, and the signal input end of the control unit is communicated with the signal output end of the sensor unit.

Description

Technical Field

[0001] This invention belongs to the field of rock mass fracturing technology, specifically a hard rock fracturing device and method based on electromagnetic induction-induced steam explosion. Background Technology

[0002] During the excavation and resource extraction of hard rock formations, the high strength and poor joint development of these formations easily lead to high stress concentration zones, especially in deep tunnels or underground roofs and surrounding rock. When the accumulated stress exceeds the tensile or compressive strength of the rock mass, it can induce dynamic disasters such as rock bursts, spalling, or sudden roof collapses, seriously threatening engineering safety and the lives of construction workers. Efficient and controllable fracturing treatment of hard rock has become a key technical aspect for achieving safe and efficient resource extraction.

[0003] To prevent such disasters, artificial intervention methods are often used to pre-fracture hard rock to release stress and reduce the risk of disaster. Currently, the most widely used hard rock fracturing techniques include blasting fracturing, hydraulic fracturing, and mechanical fracturing.

[0004] The above technologies have achieved certain results in practical applications, but still have the following shortcomings: ① High safety risks: blasting fracturing relies on explosives, which poses risks during transportation and storage; ② Poor adaptability to rock formations: hydraulic fracturing is difficult to form effective fractures in dense and hard rock formations and relies on a large amount of water; ③ Insufficient efficiency and effectiveness: mechanical cutting is labor-intensive, time-consuming, and energy-intensive, but the depressurization depth is insufficient; ④ Lack of controllability: existing technologies cannot accurately adjust the depressurization intensity, resulting in insufficient energy release or excessive damage.

[0005] Therefore, there is an urgent need for a new hard rock fracturing technology that is highly safe, has broad applicability to rock formations, provides good fracturing effect, and allows for controllable energy release. Summary of the Invention

[0006] To address the problems of high safety risks, low energy efficiency, difficulty in precisely controlling fracture direction, and potential environmental pollution associated with traditional rock fracturing methods (such as blasting and hydraulic fracturing), this invention provides a hard rock fracturing device and method based on electromagnetic induction-induced steam explosion.

[0007] This invention is achieved using the following technical solution: a hard rock fracturing device based on electromagnetic induction-induced steam explosion, comprising a pressure-sealed container, an electromagnetic induction heating system, a high-speed pressure relief valve, a sensor unit for measuring the internal temperature and pressure of the pressure-sealed container, and a control unit; the pressure-sealed container has an opening at its top, and an upper sealing cover is installed at the opening; the electromagnetic induction heating system is installed on the upper outer side of the pressure-sealed container; at least one pair of high-speed pressure relief valves are provided, and the two high-speed pressure relief valves in the pair are symmetrically connected to the lower middle outer side of the pressure-sealed container through flanges and communicate with the interior of the pressure-sealed container; the control unit is located outside the pressure-sealed container, and the signal output terminal of the control unit communicates with the control terminals of the electromagnetic induction heating system and the high-speed pressure relief valve, while the signal input terminal of the control unit communicates with the signal output terminal of the sensor unit.

[0008] Furthermore, the pressure sealing container has a cylindrical outer contour, and two pairs of pressure relief ports are arranged vertically in the lower part of the pressure sealing container. Each pressure relief port is connected to a high-speed pressure relief valve. The two pairs of pressure relief ports are symmetrically distributed on both sides of the pressure sealing container, and the axis of each pressure relief port is perpendicular to the axis of the pressure sealing container. The centers of the two pressure relief ports on the same side are located on the same generatrix of the cylinder.

[0009] Furthermore, the outlet end of each high-speed pressure relief valve is connected to a directional pressure relief device; the directional pressure relief device is a conical cylindrical structure with openings at both ends, and its larger diameter end is connected to the outlet end of the high-speed pressure relief valve.

[0010] Furthermore, the high-speed pressure relief valve adopts a rupture disc type pressure relief device; the rupture disc type pressure relief device is fixedly installed on the pressure relief port by a flange and bolts; the rupture disc type pressure relief device includes a clamp, a rupture disc installed in the clamp, and a miniature electric detonator installed on the rupture disc; the lead of the miniature electric detonator is led out through a miniature sealed terminal on the clamp and communicates with the signal output terminal of the control unit.

[0011] Furthermore, the electromagnetic induction heating system includes an induction coil wound into a helical tube shape, a heating power supply, and cables, with the induction coil integrated on the outer circumferential surface of the upper part of the pressure-sealed container.

[0012] Furthermore, the sensor unit consists of a pressure sensor and a temperature sensor; the signal output terminals of the pressure sensor and the temperature sensor are connected to the control unit via a wireless receiving module.

[0013] A hard rock fracturing method based on electromagnetic induction-induced steam explosion includes the following steps: S1: Through on-site in-situ stress measurement and rock mechanics analysis, determine the key fracture parameters and fracture target locations of the target hard rock mass, and construct boreholes accordingly; S2: Place the pressure-sealed container containing the liquid working fluid at the target depth in the borehole, ensuring that the high-speed pressure relief valve is aligned with the predetermined fracture-causing rock layer. S3: The liquid working medium inside the pressure-sealed container is heated by an electromagnetic induction heating system, so that the liquid working medium gradually reaches and is maintained in a superheated liquid state. S4: By remote control command, the high-speed pressure relief valve installed on the pressure sealing container is quickly opened, causing the pressure inside the pressure sealing container to drop sharply, triggering the superheated liquid to cause a steam explosion. The steam after the explosion rushes out of the pressure sealing container through the high-speed pressure relief valve and the directional pressure relief structure, forming a directional shock wave. S5: The directional shock wave generated by the steam explosion is used to crack the target hard rock, so that the target hard rock forms an effective fracture. S6: Depending on the actual rock strata fracturing requirements, repeat steps S2 to S5 above until the target area rock mass reaches the predetermined fracturing range or pressure relief effect.

[0014] The present invention, through the above-described apparatus and method, can achieve the following beneficial effects: 1. Controllable fracture direction: The blast energy is precisely guided by the directional pressure relief structure, improving the accuracy of pressure relief; 2. High energy efficiency: Electromagnetic induction heating is fast and has high thermal efficiency; the steam explosion releases enormous energy instantly. 3. Wide applicability: The device can be designed to adapt to boreholes of different diameters or surface deployment, and can crack a wide variety of rock types, releasing steam at different pressures depending on the type of rock. 4. Safety and environmental protection: No explosives are used, the main medium is water, and it can be remotely controlled, which significantly improves operational safety and reduces the risk of environmental pollution. Attached Figure Description

[0015] The accompanying drawings, which constitute a part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 These are left and right axial side views of a hard rock fracturing device according to an embodiment of the present invention; Figure 2 This is a partial orthogonal sectional view of a hard rock fracturing device according to an embodiment of the present invention; Figure 3 This is a rear view of a hard rock fracturing device according to an embodiment of the present invention; Figure 4 This is a top view of a hard rock fracturing device according to an embodiment of the present invention; In the attached diagram: 1. Upper sealing cover; 2. Pressure sealing container; 3. Electromagnetic induction heating system; 4. Pressure relief port; 5. Flange; 6. High-speed pressure relief valve; 61. Clamp; 62. Rupture disc; 7. Liquid working fluid; 8. Directional pressure relief device; 9. Sensor unit. Detailed Implementation

[0016] A hard rock fracturing device based on electromagnetic induction-induced steam explosion includes a pressure-sealed container 2, an electromagnetic induction heating system 3, a high-speed pressure relief valve 6, a sensor unit 9 for measuring the internal temperature and pressure of the pressure-sealed container 2, and a control unit. The pressure-sealed container 1 has an opening at its top, with an upper sealing cover 1 installed at the opening. The electromagnetic induction heating system 3 is installed on the upper outer side of the pressure-sealed container 2. At least one pair of high-speed pressure relief valves 6 are present, each pair symmetrically connected to the lower outer side of the pressure-sealed container 2 via flanges 5 and communicating with the interior of the pressure-sealed container 2. The control unit is located outside the pressure-sealed container 2. The signal output terminal of the control unit communicates with the control terminals of the electromagnetic induction heating system 3 and the high-speed pressure relief valves 6, and the signal input terminal of the control unit communicates with the signal output terminal of the sensor unit 9. Communication includes both cable connection and wireless communication via a wireless transceiver module.

[0017] The pressure sealing container 2 has a cylindrical outer contour, with two pairs of pressure relief ports 4 arranged vertically at the bottom. Each pressure relief port 4 is connected to a high-speed pressure relief valve 6. The two pairs of pressure relief ports 4 are symmetrically distributed on both sides of the pressure sealing container 2, and the axis of each pressure relief port 4 is perpendicular to the axis of the pressure sealing container 2. The centers of the two pressure relief ports 6 on the same side are located on the same generatrix of the cylinder.

[0018] The outlet end of the high-speed pressure relief valve 6 is connected to a directional pressure relief device 8. The directional pressure relief device 8 is a conical cylindrical structure with open ends. Its large-diameter end is connected to the outlet end of the high-speed pressure relief valve 6 through a flange. It is used to guide the release direction of the high-pressure gas flow and shock wave generated by the steam explosion, so that it acts on the target rock layer in a concentrated and directional manner, and the direction of the fracture can be controlled.

[0019] The high-speed pressure relief valve 6 adopts a commercially available rupture disc type pressure relief device; the rupture disc type pressure relief device is fixedly installed on the pressure relief port 4 by flange 5 and bolts; the rupture disc type pressure relief device includes a clamp 61, a rupture disc 62 installed in the clamp 61, and a miniature electric detonator installed on the rupture disc 62; the lead of the miniature electric detonator is led out through the miniature sealed terminal on the clamp 61 and communicates with the signal output terminal of the control unit.

[0020] The electromagnetic induction heating system 3 includes an induction coil wound into a spiral tube shape, a heating power supply, and cables. The induction coil is integrated on the outer circumferential surface of the upper part of the pressure-sealed container 2. The heating power supply is a high-frequency power supply. Typically, the leads at both ends of the induction coil are led out through insulated sealed terminals on the pressure-sealed container 2 and connected to an external high-frequency power supply. The high-frequency power supply is a power source (at least 240V AC) that provides the induction coil with the required frequency and power. The induction coil is supplied with a high-frequency alternating current to generate an alternating magnetic field, thereby heating the pressure-sealed container 2 and indirectly causing the liquid working fluid 7 to be in a superheated state.

[0021] The sensor unit 9 consists of a pressure sensor and a temperature sensor; the signal output terminals of the pressure sensor and the temperature sensor are connected to the control unit via a wireless receiving module.

[0022] A hard rock fracturing method based on electromagnetic induction-induced steam explosion includes the following steps: S1: Through on-site in-situ stress measurement and rock mechanics analysis, determine the key fracture parameters and fracture target locations of the target hard rock mass, and construct boreholes accordingly; S2: Place the pressure-sealed container 2 containing the liquid working medium 7 at the target depth in the borehole, and ensure that the pressure relief direction of the high-speed pressure relief valve 6 is aligned with the predetermined fracture-causing rock layer. S3: The liquid working medium 7 in the pressure sealing container 2 is heated by the electromagnetic induction heating system 3, so that the liquid working medium 7 gradually reaches and is maintained in a superheated liquid state. S4: By remote control command, the high-speed pressure relief valve 6 installed on the pressure sealing container 2 is quickly opened, causing the pressure inside the pressure sealing container 2 to drop sharply, triggering the superheated liquid to cause a steam explosion. The steam after the explosion rushes out of the pressure sealing container through the high-speed pressure relief valve 6 and the directional pressure relief structure 8, forming a directional shock wave. S5: The directional shock wave generated by the steam explosion is used to crack the target hard rock, so that the target hard rock forms an effective fracture. S6: Depending on the actual rock strata fracturing requirements, repeat steps S2 to S5 above until the target area rock mass reaches the predetermined fracturing range or pressure relief effect.

[0023] This invention provides a hard rock fracturing device and method based on electromagnetic induction-induced steam explosion. It utilizes electromagnetic induction to efficiently heat a liquid working medium 7 (such as water) to a superheated state in a confined space, and triggers high-speed pressure release through remote command to instantly release pressure and cause a violent steam explosion. The shock wave generated by the explosion is directed to the target rock layer, achieving the effects of controllable fracture direction, high energy efficiency, wide applicability, safety and environmental protection.

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and should not be construed as limiting the invention.

[0025] like Figure 1-4 As shown, a hard rock fracturing device based on electromagnetic induction-induced steam explosion is disclosed. The device is generally cylindrical and includes an upper sealing cover 1, a pressure sealing container 2, an electromagnetic induction heating system 3, a pressure relief port 4, a flange 5, a high-speed pressure relief valve 6, a directional pressure relief structure 8, and a sensor unit 9. The positioning of each component satisfies the following relationship: the electromagnetic induction heating system 3 is located on the upper part of the pressure sealing container 2; the high-speed pressure relief valve 6 is symmetrically distributed on both sides of the pressure sealing container 2; the inlet of the directional pressure relief structure 8 is connected to the outlet of the high-speed pressure relief valve 6, which can guide the high-pressure gas flow and shock wave released by the steam explosion, so that it acts on the target rock layer in a concentrated and directional manner, achieving controllable fracture direction; the sensor unit 9 is located inside the upper sealing cover 1 of the pressure sealing container 2; and the control unit is located outside the pressure sealing container 2.

[0026] In this embodiment, the pressure sealing container 2 is the core pressure-bearing component of the device. It is made of high-strength, low-alloy materials and conforms to the GB713 standard. The pressure sealing container 2 is a thick-walled cylindrical structure formed in one piece or welded in sections. Its wall thickness is 10mm and its design pressure bearing capacity is 100MPa.

[0027] The pressure-sealed container 2 has a sealed cylindrical pressure chamber inside, used to contain the liquid working medium 7: water + ethanol. The addition of ethanol can effectively lower the boiling point of the liquid working medium 7, resulting in a greater force when the vapor explodes. The cylinder and bottom end cap of the pressure-sealed container 2 are integrally formed, and the top of the cylinder is sealed with an upper sealing cap 1. Of course, the upper sealing cap 1 is removable, which facilitates the addition of the liquid working medium 7 to the pressure-sealed container 2.

[0028] The pressure-sealed container 2 has two symmetrical pressure relief ports 4, with the center lines of the two ports forming a strict 180° angle (tolerance ±1°). The axis is perpendicular to the cylinder axis and extends from the outer wall to the inner wall, enabling zero-direction radial injection of the shock wave and significantly improving energy utilization. Optionally, there are two pairs of pressure relief ports 4, arranged vertically.

[0029] The induction coil in the electromagnetic induction heating system 3 is integrated on the outer circumferential surface of the pressure sealing container 2. The induction coil is wound into a spiral tube shape with an axial span of 100mm, 10 turns, and a turn spacing of 10mm±1mm. Joule heat is generated in the metal by utilizing eddy current effect and hysteresis loss. The heat is transferred to the liquid working medium 6 in the pressure sealing container 3 through thermal conduction, with a thermal efficiency of ≥85%.

[0030] In some embodiments, a solid-state high-frequency induction heating power supply with a rated output power of 30KW and an operating frequency of 20kHz is used. The power supply output terminal is connected to the lead terminal of the induction coil via a cable. An LC matching compensation network (composed of capacitor and inductor) is provided between the power supply and the induction coil to match the load impedance with the power supply output impedance, ensuring efficient power transmission.

[0031] In some embodiments, a rupture disc type pressure relief device can be selected as the high-speed pressure relief valve 6, with the fastest opening speed (microsecond level). The rupture disc 61 is installed inside the clamp 61, and a positively arched grooved metal rupture disc is selected, with a rated burst pressure of 30MPa. The positively arched surface of the rupture disc 62 faces the chamber of the pressure sealing container 2. The clamp 61 is fastened to the flange 5 through a flange and double-ended studs, and the clamp 61 is made of 316 stainless steel.

[0032] The rupture disc 62 is triggered by a miniature electric detonator. A miniature electric detonator is installed in the holder 61 with its lead wires close to the non-pressure surface of the rupture disc 62. The miniature electric detonator can switch from a fully closed to a fully open state in a very short time after receiving the opening command.

[0033] The directional pressure relief structure 8 is used to guide the release direction of the high-speed gas flow and shock wave generated by the steam explosion, so that it acts on the target rock layer in a concentrated and directional manner, thereby making the direction of the fracture controllable.

[0034] The directional pressure relief structure 8 can adopt a conical convergent structure, which is integrally machined from high-strength heat-resistant alloy steel (such as GH3030). The inlet end matches the flange of the outlet of the clamp 61 and is tightly connected by bolts, nuts and metal spiral wound gaskets. The outlet of the conical convergent structure can be precisely adjusted and fixed to face the target top rock layer during installation.

[0035] The sensor unit 8 consists of a pressure sensor for testing the internal pressure of the pressure-sealed container 2 and a temperature sensor for testing the temperature of the liquid working medium 7. The sensing end of the pressure sensor extends into the sealed cavity of the pressure-sealed container 2 through a first sensor interface, and its signal output is connected to the control unit via a wireless receiving module. The sensing end of the temperature sensor (e.g., a platinum resistance element) extends into the sealed cavity of the pressure-sealed container 2 and is located within the liquid working medium 7 through a second sensor interface on the pressure-sealed container 2, and its signal output is connected to the control unit via a wireless receiving module. The interface of the sensor unit 9 (connecting to the wireless receiving module) employs a high-pressure, high-temperature sealing structure (e.g., a welded sealing seat).

[0036] The control unit, an industrial-grade PLC controller (e.g., Siemens S7-1200 series), is installed inside the outer end cover of the pressure sealing vessel.

[0037] The control unit consists of an input module, an output module, and a communication module. The input module receives analog and digital inputs. The analog inputs primarily come from signals from pressure and temperature sensors, while the digital inputs receive remote trigger signals. The output module's analog outputs mainly provide 0-10V or 4-20mA signals to the power regulation terminal of the high-frequency power supply. The relay outputs primarily control the start and stop of the main circuit contactor of the high-frequency power supply. A dedicated output channel provides a pulse signal with sufficient energy to trigger a miniature detonating tube through a corresponding drive circuit. The communication module mainly integrates an Ethernet interface, supports Modbus TCP / RTU protocols, and typically includes a 4G / 5G DTU module to remotely monitor sensor data and receive remote operation commands.

[0038] The PLC control logic first sets the target liquid working medium 7 temperature (e.g., 320℃). Based on feedback from the temperature sensor, the PLC uses a PID algorithm to adjust the analog signal output to the high-frequency power supply, controlling the heating power to raise the temperature of the liquid working medium 7 and maintain it within the target value ±5℃ range. Simultaneously, it detects the pressure sensor signal; if the pressure exceeds the safety threshold, heating is immediately stopped and an alarm is triggered. The PLC can detect and record parameters such as internal pressure, temperature, heating power, and running time of the pressure-sealed container 2 in real time. When the PLC receives an encrypted command from the remote control terminal, after confirming that the system is in a "READY" state (pressure and temperature have reached the set values ​​and are stable, with no fault alarms), the PLC sends a 100ms 24VDC ignition pulse to the miniature electric detonator through a dedicated output channel, detonating the miniature electric detonator and puncturing the rupture disc 61, achieving instantaneous pressure relief. The PLC control program includes safety logic, such as overpressure and overtemperature protection.

[0039] The hard rock fracturing method of this invention employs any of the hard rock fracturing devices described above, and the hard rock fracturing method includes the following steps: S1: Through on-site in-situ stress testing, rock mass structure scanning and numerical simulation, determine the high-stress zone and natural joint distribution in the target hard rock layer, and plan the drilling location, depth and dip angle accordingly, and complete the drilling construction. S2: Inject a certain proportion of water and ethanol mixture (as liquid working medium 7) into the pressure sealing container 2, place the pressure sealing container 2 into the pre-drilled hole, and ensure that the pressure relief port 4 is precisely aligned with the rock layer to be pre-fractured. S3: The high-frequency power supply is started through the PLC control system, so that the induction coil of the electromagnetic induction heating system 3 generates an alternating electromagnetic field to heat the liquid working medium 7 in the pressure sealing container 2. The heating power is adjusted in real time by adopting the PID closed-loop control strategy to maintain the temperature and internal pressure of the liquid working medium 7 within the set threshold range, forming a stable superheated liquid state. S4: The operator sends a command through the remote terminal. After the PLC confirms the command, it sends a signal to detonate the miniature electric detonator, which instantly punctures the rupture disc 61, causing the pressure inside the pressure-sealed container 2 to drop suddenly to atmospheric pressure, triggering a violent steam explosion. S5: The high-temperature and high-pressure steam and shock wave generated by the explosion are ejected from the pressure relief port 4 and converged into a high-speed jet through the conical directional pressure relief device 8, which directionally impacts the hard rock mass and forms a controllable fracture network. S6: Based on the real-time monitoring of rock mass fracturing and stress release, repeat steps S2 to S5 above, processing different sections one by one until the target hard rock layer reaches the predetermined fracturing range and stress relief effect.

[0040] The device structure, connection method, material selection, parameter range, and working process of the present invention have been described in detail above with reference to specific embodiments. It should be emphasized that these specific parameters and details are for illustrative purposes only and are not intended to limit the present invention. Under the premise of the inventive concept, those skilled in the art can make various modifications, substitutions, or combinations to the above embodiments, and all such modifications should be considered to fall within the protection scope defined by the claims of the present invention.

Claims

1. A hard rock fracturing device based on electromagnetic induction-induced steam explosion, characterized in that: The system includes a pressure-sealed container (2), an electromagnetic induction heating system (3), a high-speed pressure relief valve (6), a sensor unit (9) for measuring the internal temperature and pressure of the pressure-sealed container (2), and a control unit. The pressure-sealed container (1) has an opening at its top, and an upper sealing cover (1) is installed at the opening. The electromagnetic induction heating system (3) is installed on the upper outer side of the pressure-sealed container (2). There is at least one pair of high-speed pressure relief valves (6), and the two pairs of high-speed pressure relief valves (6) are symmetrically connected to the lower middle outer side of the pressure-sealed container (2) through flanges (5) and communicate with the interior of the pressure-sealed container (2). The control unit is located outside the pressure-sealed container (2), and the signal output terminal of the control unit communicates with the control terminal of the electromagnetic induction heating system (3) and the high-speed pressure relief valve (6), and the signal input terminal of the control unit communicates with the signal output terminal of the sensor unit (9).

2. The hard rock fracturing device based on electromagnetic induction-induced steam explosion as described in claim 1, characterized in that, The pressure sealing container (2) has a cylindrical outer contour. The lower part of the pressure sealing container (2) has two pairs of pressure relief ports (4) arranged vertically. Each pressure relief port (4) is connected to a high-speed pressure relief valve (6). The two pairs of pressure relief ports (4) are symmetrically distributed on both sides of the pressure sealing container (2). The axis of each pressure relief port (4) is perpendicular to the axis of the pressure sealing container (2). The centers of the two pressure relief ports (4) on the same side are located on the same generatrix of the cylinder.

3. The hard rock fracturing device based on electromagnetic induction-induced steam explosion as described in claim 2, characterized in that, The outlet end of the high-speed pressure relief valve (6) is connected to a directional pressure relief device (8); the directional pressure relief device (8) is a conical cylindrical structure with open ends, and its large-diameter end is connected to the outlet end of the high-speed pressure relief valve (6).

4. The hard rock fracturing device based on electromagnetic induction-induced steam explosion as described in claim 3, characterized in that, The high-speed pressure relief valve (6) adopts a rupture disc type pressure relief device; the rupture disc type pressure relief device is fixedly installed on the pressure relief port (4) by flange (5) and bolts; the rupture disc type pressure relief device includes a clamp (61), a rupture disc (62) installed in the clamp (61) and a miniature electric detonator installed on the rupture disc (62); the lead wire of the miniature electric detonator is led out through the miniature sealed terminal on the clamp (61) and communicates with the signal output terminal of the control unit.

5. A hard rock fracturing device based on electromagnetic induction-induced steam explosion as described in claim 4, characterized in that, The electromagnetic induction heating system (3) includes an induction coil wound into a spiral tube shape, a heating power supply and cables, and the induction coil is integrated on the outer circumferential surface of the upper part of the pressure-sealed container (2).

6. The hard rock fracturing device based on electromagnetic induction-induced steam explosion as described in claim 5, characterized in that, The sensor unit (9) consists of a pressure sensor and a temperature sensor; the signal output terminals of the pressure sensor and the temperature sensor are connected to the control unit through a wireless receiving module.

7. A hard rock fracturing method based on electromagnetic induction-induced steam explosion, implemented using the hard rock fracturing device based on electromagnetic induction-induced steam explosion as described in any one of claims 3-6, characterized in that, Includes the following steps: S1: Through on-site in-situ stress measurement and rock mechanics analysis, determine the key fracture parameters and fracture target locations of the target hard rock mass, and construct boreholes accordingly; S2: Place the pressure-sealed container (2) containing the liquid working medium (7) inside at the target depth in the borehole, and ensure that the pressure relief valve (6) is aligned with the predetermined fracture rock layer orientation. S3: The liquid working medium (7) in the pressure sealing container (2) is heated by the electromagnetic induction heating system (3) so that the liquid working medium (7) gradually reaches and is maintained in a superheated liquid state; S4: By remote control command, the high-speed pressure relief valve (6) installed on the pressure sealing container (2) is quickly opened, causing the pressure inside the pressure sealing container (2) to drop sharply, triggering the superheated liquid to cause a steam explosion. The steam after the explosion rushes out of the pressure sealing container (2) through the high-speed pressure relief valve (6) and the directional pressure relief structure 8, forming a directional shock wave. S5: The directional shock wave generated by the steam explosion is used to crack the target hard rock, so that the target hard rock forms an effective fracture. S6: Depending on the actual rock strata fracturing requirements, repeat steps S2 to S5 above until the target area rock mass reaches the predetermined fracturing range or pressure relief effect.

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