High-temperature and high-pressure drilling rock crushing simulation experiment device

Abstract

The invention provides a high-temperature and high-pressure drilling rock crushing simulation experiment device which comprises a shell, a rock sample, a driving module, a drilling module, a first pressure module, a second pressure module and a heating module. A first mounting cavity and a second mounting cavity are formed in the shell; the rock sample is arranged in the second mounting cavity; the driving module is arranged in the first mounting cavity, and an output rotating shaft of the driving module extends into the second mounting cavity; the drilling module comprises a drilling rod and a feeding assembly, the drilling rod is connected with the output rotating shaft, and the feeding assembly is suitable for driving the rock sample to move in the direction close to the drilling rod; the first pressure module is suitable for circularly conveying a high-pressure and low-temperature first fluid medium into the first mounting cavity; the second pressure module is suitable for conveying a high-pressure second fluid medium into the second mounting cavity; the heating module is arranged on the shell so as to be suitable for heating the second fluid medium. The problems that a rock crushing simulation experiment device is insufficient in reduction to a deep high-temperature and high-pressure environment, low in sealing reliability and poor in heat dissipation of a driving motor can be solved.

Description

Technical Field

[0001] This invention relates to the field of geological drilling experimental testing technology, and in particular to a high-temperature and high-pressure drilling rock-breaking simulation experimental device. Background Technology

[0002] In the field of fossil energy resource drilling technology, the demand for energy exploration and development in deep underground (>4500m) and deep sea (>300m) areas is increasing. As drilling depth advances into the Earth's crust, formation temperature and pressure increase exponentially. Calculations based on geothermal gradients show that the bottom-hole temperature of wells at depths of 10,000 meters can reach over 200℃, and the pressure exceeds 100MPa. However, under the extreme conditions of high temperature and high pressure in deep geological formations, traditional drilling equipment faces risks such as electronic equipment failure, changes in the physical and chemical properties of rocks, and damage to the drilling fluid system, making technological breakthroughs extremely difficult. Given that theoretical models cannot accurately describe the fracturing behavior of deep rocks under extreme conditions, physical simulation experiments have become a key path to overcome technological bottlenecks. By simulating the rock-breaking process under high temperatures of 200-300℃ and high pressures of 100-175MPa, we can guide the design of high-temperature resistant drill bits, optimize drilling parameters, and develop new high-temperature resistant drilling fluids, providing a scientific basis for deep drilling.

[0003] Most existing rock breaking devices have a maximum pressure of less than 100 MPa and a temperature limit of 200-300℃, which cannot reproduce the "double high" coupling effect at a depth of 10,000 meters. In addition, most rock breaking devices also have the following problems: (1) Dynamic sealing structures (such as rotary shaft seals) are usually used to connect the drive motor and the drill bit. Under high temperature and high pressure, dynamic sealing components (such as rubber seals and mechanical seals) are prone to aging and deformation, resulting in leakage of working medium, which seriously affects the equipment life and operational safety; (2) The drive motor is prone to winding insulation failure due to poor heat dissipation under high temperature conditions. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one objective of this invention is to provide a high-temperature, high-pressure drilling rock-breaking simulation experimental device, which addresses the problems of insufficient simulation of deep high-temperature, high-pressure environments, low sealing reliability, and poor heat dissipation of drive motors in existing rock-breaking simulation experimental devices.

[0005] This invention proposes a high-temperature and high-pressure drilling rock-breaking simulation experimental device, which includes a shell, a rock sample, a drive module, a drilling module, a first pressure module, a second pressure module, and a heating module. A sealed cavity is formed inside the shell, and a middle partition is provided within the shell, defining the sealed cavity as a first mounting cavity and a second mounting cavity. The rock sample is placed in the second mounting cavity. The drive module is located in the first mounting cavity, and a through hole is formed in the middle partition, through which the output shaft of the drive module extends into the second mounting cavity. The drilling module includes a drill rod and a feed assembly; the drill rod is connected to the output shaft, and a drill bit is provided at the end of the drill rod. The drill rod is axially aligned with the rock sample; the feed assembly is connected to the rock sample and adapted to drive the rock sample to move in a direction close to the drill rod; a first pressure module is connected to a first mounting cavity to circulate a first fluid medium into the first mounting cavity; and the first pressure module includes a first high-pressure pump and a radiator, the first high-pressure pump being adapted to pressurize the first fluid medium and the radiator being adapted to cool the first fluid medium; a second pressure module is connected to a second mounting cavity to deliver a second fluid medium into the second mounting cavity; and the second pressure module includes a second high-pressure pump adapted to pressurize the second fluid medium; a heating module is disposed in the housing to heat the second fluid medium.

[0006] The high-temperature and high-pressure drilling rock-breaking simulation experimental device of the present invention, by setting up a first pressure module, a second pressure module, and a heating module to heat and pressurize the rock sample, and utilizing the large temperature and pressure adjustment range of the fluid medium, can highly reproduce the high-temperature and high-pressure environmental conditions of drilling rock breaking, simulating a high-temperature environment of 200-300℃ and a high-pressure environment of 100-175MPa. By placing the drive module, rock sample, and drilling module in the same sealed cavity and using a static sealing structure to achieve sealing, the present invention can reduce the sealing difficulty, improve the sealing reliability of the device, reduce the risk of leakage, and enable the present invention to operate stably for a long time under high-pressure conditions of 100-175MPa. By circulating the fluid medium to cool the drive module, the present invention can achieve effective heat dissipation and cooling of the drive module, controlling the motor operating temperature below 150℃, reducing the impact of medium heating on the drive module, avoiding insulation aging caused by high temperature, and significantly improving the motor life. The present invention can solve the problems of insufficient reproduction of deep high-temperature and high-pressure environment, low sealing reliability, and poor heat dissipation of drive motor in rock-breaking simulation experimental devices.

[0007] According to some embodiments of the present invention, the housing includes an upper top shell and a lower base, an intermediate partition is disposed between the upper top shell and the lower base, a first sealing element is disposed between the intermediate partition and the upper top shell, and a second sealing element is disposed between the intermediate partition and the lower base.

[0008] According to some embodiments of the present invention, both the upper shell and the lower base are constructed as a double-wall structure; and a structural gap is formed inside the lower base, which is filled with heat-insulating material.

[0009] According to some embodiments of the present invention, the heating module includes an electromagnetic coil disposed at the bottom of the lower base to be adapted to heat a second fluid medium.

[0010] According to some embodiments of the present invention, the high-temperature and high-pressure drilling rock breaking simulation experimental device further includes a temperature sensor and a pressure sensor; the temperature sensor is configured to have at least two sensors, which are respectively disposed in the first mounting cavity and the second mounting cavity to detect the temperature of the first fluid medium and the second fluid medium; the pressure sensor is configured to have at least one sensor, which is disposed in the second mounting cavity to detect the pressure of the second fluid medium.

[0011] According to some embodiments of the present invention, a first fluid medium and a second fluid medium fill the sealed cavity, and a portion of the first fluid medium fills the second mounting cavity; a medium interface is formed between the first fluid medium and the second fluid medium, the medium interface being formed in the second mounting cavity and spaced apart from the intermediate partition.

[0012] According to some embodiments of the present invention, the feed assembly includes a feed cylinder and a feed pump. The output end of the feed cylinder is connected to a rock sample to facilitate pushing the rock sample to move axially along the drill pipe. The feed pump is connected to the feed cylinder via a feed oil pipe to facilitate supplying a power medium to the feed cylinder.

[0013] According to some embodiments of the present invention, a solid self-lubricating bearing is provided in the through hole, and the output shaft is connected to the inner ring of the solid self-lubricating bearing.

[0014] According to some embodiments of the present invention, the housing is provided with a safety valve.

[0015] According to some embodiments of the present invention, the high-temperature and high-pressure drilling rock breaking simulation experimental device further includes a clamping module, which is disposed in the second mounting cavity to limit the rock sample.

[0016] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0018] Figure 1 This is a schematic diagram of the structure of a high-temperature and high-pressure drilling rock-breaking simulation experimental device according to some embodiments of the present invention;

[0019] Figure 2 This is a schematic diagram of the drilling state of a high-temperature and high-pressure drilling rock-breaking simulation experimental device according to some embodiments of the present invention;

[0020] Figure 3 This is an assembly diagram of the output shaft of a drive module according to some embodiments of the present invention;

[0021] Figure 4 This is a schematic diagram of the sealing of a housing according to some embodiments of the present invention;

[0022] Figure 5 This is a schematic diagram of the structure of the intermediate partition according to some embodiments of the present invention.

[0023] Figure label:

[0024] Upper top shell 11; lower base 12; middle partition 13; through hole 131; fixing bolt 14; first seal 15; second seal 16; safety valve 17; drain bolt 18;

[0025] 21. Permanent magnet; 22. Rotor; 23. Power supply; 24. Output shaft; 25. Solid self-lubricating bearing;

[0026] 30 rock samples; 40 clamping modules;

[0027] First fluid medium 51; inlet pipe 52; return pipe 53; first high-pressure pump 54; radiator 55;

[0028] Second fluid medium 61; high-pressure pipe 62; second high-pressure pump 63;

[0029] 71. Drill pipe; 72. Drill bit; 73. Feed cylinder; 74. Feed pump; 75. Feed pipe;

[0030] Electromagnetic coil 80;

[0031] Data acquisition line 91; computer 92. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0033] The following is for reference. Figures 1-5 A high-temperature and high-pressure drilling rock-breaking simulation experimental apparatus according to an embodiment of the present invention is described.

[0034] This invention proposes a high-temperature and high-pressure drilling rock-breaking simulation experimental device, which includes a shell, a rock sample 30, a drive module, a drilling module, a first pressure module, a second pressure module, and a heating module. A sealed cavity is formed inside the shell, and a middle partition 13 is provided within the shell, defining the sealed cavity as a first mounting cavity and a second mounting cavity. The rock sample 30 is placed in the second mounting cavity. The drive module is placed in the first mounting cavity, and a through hole 131 is formed in the middle partition 13, through which the output shaft 24 of the drive module extends into the second mounting cavity. The drilling module includes a drill rod 71 and a feed assembly. The drill rod 71 is connected to the output shaft 24, and a drill bit 72 is provided at the end of the drill rod 71. The feed assembly is axially aligned with the rock sample 30 and is adapted to drive the rock sample 30 to move in a direction close to the drill pipe 71; the first pressure module is connected to the first mounting cavity to circulate and deliver the first fluid medium 51 into the first mounting cavity; and the first pressure module includes a first high-pressure pump 54 and a radiator 55, the first high-pressure pump 54 being adapted to pressurize the first fluid medium 51 and the radiator 55 being adapted to cool the first fluid medium 51; the second pressure module is connected to the second mounting cavity to deliver the second fluid medium 61 into the second mounting cavity; and the second pressure module includes a second high-pressure pump 63, the second high-pressure pump 63 being adapted to pressurize the second fluid medium 61; a heating module is disposed in the housing to heat the second fluid medium 61.

[0035] According to the high-temperature and high-pressure drilling rock-breaking simulation experimental device of the present invention, the drive module drives the drill rod 71 to rotate through the output shaft 24, and the feed component drives the rock sample 30 to move towards the drill rod 71, such as... Figure 2 As shown, a drill bit 72 is provided at the end of the drill rod 71. When the drill rod 71 rotates, it drills and breaks down the rock sample 30. The position of the drive module remains unchanged during drilling. A first pressure module and a second pressure module can input high-pressure first fluid medium 51 and second fluid medium 61 into the sealed cavity. A heating module can heat the second fluid medium 61. The rock sample 30 is placed in the second mounting cavity and is in contact with the second fluid medium 61, allowing it to exchange heat with the second fluid medium 61 and withstand the pressure applied by the second fluid medium 61. A first high-pressure pump 54 can pressurize the first fluid medium 51 in the first mounting cavity, and a second high-pressure pump 63 can pressurize the second fluid medium 61 in the second mounting cavity. The second fluid medium 61 of this invention can simulate the high-pressure and high-temperature environment of drilling and rock breaking. Simultaneously, the drive module is placed in the first mounting cavity and is in contact with the first fluid medium 51, allowing it to exchange heat with the first fluid medium 51. The first pressure module is equipped with a radiator 55 to cool the circulating first fluid medium 51, so that the first fluid medium 51 can cool the drive module.

[0036] The pressure within the sealed cavity is determined by the pressure of the first fluid medium 51 and the pressure of the second fluid medium 61. During pressurization, the pressures of the two media can be dynamically adjusted to compensate for pressure fluctuations; after pressurization is completed, the first fluid medium 51 and the second fluid medium 61 reach pressure equilibrium.

[0037] The high-temperature and high-pressure drilling rock-breaking simulation experimental device of the present invention, by setting up a first pressure module, a second pressure module, and a heating module to heat and pressurize the rock sample 30, and utilizing the large temperature and pressure adjustment range of the fluid medium, can highly reproduce the high-temperature and high-pressure environmental conditions of drilling rock breaking, simulating a high-temperature environment of 200-300℃ and a high-pressure environment of 100-175MPa. By placing the drive module, rock sample 30, and drilling module in the same sealed cavity and using a static sealing structure to achieve sealing, the present invention can reduce the sealing difficulty, improve the sealing reliability of the device, reduce the risk of leakage, and enable the present invention to operate stably for a long time under high-pressure conditions of 100-175MPa. By circulating the fluid medium to cool the drive module, the present invention can achieve effective heat dissipation and cooling of the drive module, controlling the motor operating temperature below 150℃, reducing the impact of medium heating on the drive module, avoiding insulation aging caused by high temperature, and significantly improving the motor life. The present invention can solve the problems of insufficient reproduction of deep high-temperature and high-pressure environment, low sealing reliability, and poor heat dissipation of drive motor in rock-breaking simulation experimental devices.

[0038] In some embodiments, the first fluid medium 51 is silicone oil, and the second fluid medium 61 is deionized water. Silicone oil and deionized water have different densities and properties, and therefore will not mix. This invention employs a dual-medium isolation system, allowing the device to operate in a water-based drilling fluid environment without the need for additional special circulating media, thus reducing experimental costs.

[0039] In some embodiments, the drill rod 71 is threadedly connected to the output shaft 24, and the drill rod 71 is also threadedly connected to the drill bit 72.

[0040] According to some embodiments of the present invention, the housing includes an upper top shell 11 and a lower base 12, with a middle partition 13 disposed between the upper top shell 11 and the lower base 12. A first sealing element 15 is disposed between the middle partition 13 and the upper top shell 11, and a second sealing element 16 is disposed between the middle partition 13 and the lower base 12. In this embodiment, the housing is constructed as a split structure consisting of the upper top shell 11 and the lower base 12, which facilitates the assembly of the internal structure of the sealing cavity; the middle partition 13, disposed between the upper top shell 11 and the lower base 12, enables stable installation; by providing the first sealing element 15 and the second sealing element 16, effective sealing can be achieved at the connection between the middle partition 13 and the upper top shell 11, and at the connection between the middle partition 13 and the lower base 12, thereby achieving an overall sealing effect for the housing.

[0041] The intermediate partition 13 defines the first mounting cavity between itself and the upper top shell 11, and the intermediate partition 13 defines the second mounting cavity between itself and the lower base 12. The intermediate partition 13 is connected to the upper top shell 11 and the lower base 12 by fixing bolts 14, specifically, as follows: Figure 1 , Figure 4 As shown, the upper top shell 11 and the lower base 12 have connecting protrusions. Fixing bolts 14 sequentially pass through the connecting protrusions of the upper top shell 11, the first seal 15, the intermediate partition 13, the second seal 16, and the connecting protrusions of the lower base 12. Both ends are locked with fasteners such as nuts. The sealing effect can be improved by adjusting the tightening force. In some embodiments, the upper top shell 11 and the lower base 12 have circular cross-sections, and multiple fixing bolts 14 are arranged along the circumference of the shell. The connecting protrusions and the intermediate partition 13 both have multiple connecting holes that allow the fixing bolts 14 to pass through.

[0042] In some embodiments, the first seal 15 and the second seal 16 are configured as sealing rings, each including a metal O-ring seal and a graphite spiral wound gasket seal, which can maintain an effective seal in a temperature range of 200-300°C and a pressure range of 100-175 MPa.

[0043] According to some embodiments of the present invention, both the upper top shell 11 and the lower base 12 are constructed as double-walled structures; and a structural gap is formed inside the lower base 12, which is filled with heat-insulating material. In this embodiment, the double-walled structure of the upper top shell 11 and the lower base 12 can improve structural strength, withstand internal pressure, and resist high temperature and high pressure; furthermore, the heat-insulating material filling the gap in the double-walled structure of the lower base 12 can improve the heat insulation effect of the shell portion of the second mounting cavity, which helps to restore the high-temperature conditions of drilling and rock breaking inside the second mounting cavity. In some embodiments, the inner wall of the double-walled structure is made of a high-temperature resistant, high-strength nickel-based alloy, and the outer wall is made of high-strength carbon steel.

[0044] According to some embodiments of the present invention, the drive module is configured as a drive motor, which includes a permanent magnet 21 and a rotor 22. The permanent magnet 21 is disposed on the inner wall of the upper top shell 11, and the rotor 22 is mounted on the inner side of the permanent magnet 21. An output shaft 24 is disposed at the center of the rotor 22 and is arranged vertically. The two ends of the output shaft 24 are rotatably connected to the upper top shell 11 and the intermediate partition 13 through bearings. Further, a bearing mounting groove is formed on the top of the upper top shell 11, and a bearing mounting groove is formed at the through hole 131 of the intermediate partition 13.

[0045] Furthermore, the drive module is powered by power supply 23, which is located on the outside of the housing and connected to the rotor 22 via a power cable. A power supply hole is formed on the top of the upper shell 11, and a high-temperature, high-pressure sealed terminal is located at the power supply hole, connecting to the external power cable. The high-temperature, high-pressure sealed terminal includes a sealing structure, specifically comprising a metal-ceramic composite insulation layer and a fluororubber extrusion ring.

[0046] According to some embodiments of the present invention, the upper top shell 11 is formed with a first liquid inlet and a liquid outlet communicating with the first mounting cavity; the first pressure module further includes a liquid inlet pipe 52 and a liquid return pipe 53, the liquid inlet pipe 52 and the liquid return pipe 53 are connected, and the liquid inlet pipe 52 is connected to the first liquid inlet, and the liquid return pipe 53 is connected to the liquid outlet; a first high-pressure pump 54 and a radiator 55 are disposed on the liquid inlet pipe 52 or the liquid return pipe 53. In this embodiment, the liquid inlet pipe 52 and the liquid return pipe 53 form a medium circulation pipeline communicating with the first mounting cavity; the first high-pressure pump 54 provides power to circulate the first fluid medium 51 and adjusts the medium pressure in the first mounting cavity; the radiator 55 exchanges heat with the first fluid medium 51 to cool it down, and the cooled first fluid medium 51 enters the first mounting cavity to exchange heat with the drive module to cool the drive module. In some embodiments, the liquid inlet pipe 52 is threadedly connected to the first liquid inlet, and the liquid return pipe 53 is threadedly connected to the liquid outlet.

[0047] According to some embodiments of the present invention, a second liquid inlet is formed on the lower base 12, communicating with a second mounting cavity; the second pressure module includes a high-pressure pipe 62, which communicates with the second liquid inlet and a medium source; a second high-pressure pump 63 is disposed at the liquid inlet end of the high-pressure pipe 62, the second high-pressure pump 63 provides power to input the second fluid medium 61 into the second mounting cavity, and adjusts the medium pressure in the second mounting cavity. In some embodiments, the high-pressure pipe 62 and the second liquid inlet are connected by threads.

[0048] In the two embodiments described above, the first high-pressure pump 54 and the second high-pressure pump 63 operate in conjunction during the experiment to ensure that the first fluid medium 51 and the second fluid medium 61 achieve pressure balance in order to simulate the high-pressure environment in which the rock sample 30 is located.

[0049] It should be noted that in existing rock crushing simulation devices, the rock sample 30 is mostly heated by resistance wire heating. This heating method has problems such as uneven heating, high energy consumption, and easy scaling.

[0050] To address the aforementioned problems, according to some embodiments of the present invention, the heating module includes an electromagnetic coil 80, which is disposed at the bottom of the lower base 12 to heat the second fluid medium 61. In this embodiment, the electromagnetic coil 80 generates an alternating magnetic field after being energized, inducing eddy currents at the bottom of the lower base 12; the Joule heating generated by the eddy currents heats the second fluid medium 61 within the second mounting cavity. The present invention heats the second fluid medium using the electromagnetic coil 80 to replicate the actual high-temperature environment of the rock sample 30, achieving fast, uniform, and energy-efficient heating.

[0051] Furthermore, in conjunction with the aforementioned embodiments, the side wall of the lower base 12 adopts a double-wall structure, and the electromagnetic coil 80 is arranged around the outside of the bottom wall of the lower base 12. The bottom wall of the lower base 12 can adopt a single-wall structure to facilitate heating at the bottom.

[0052] According to some embodiments of the present invention, the high-temperature and high-pressure drilling rock-breaking simulation experimental device further includes a data acquisition module, which includes a temperature sensor and a pressure sensor. The temperature sensor is configured with at least two sensors, each disposed in a first mounting cavity and a second mounting cavity, respectively, to detect the temperature of the first fluid medium 51 and the second fluid medium 61. The pressure sensor is configured with at least one sensor, disposed in the second mounting cavity, to detect the pressure of the second fluid medium 61. This embodiment, by real-time detection of the temperature and pressure of the first fluid medium 51 and the second fluid medium 61, can obtain environmental simulation data. Adjustments to the pressure and temperature of the fluid medium based on the detection results can improve the accuracy of environmental condition simulation, thereby enhancing the fidelity and reference value of the experimental simulation. In some embodiments, a pressure sensor is also disposed in the first mounting cavity to continuously monitor the pressure of the first fluid medium 51 during the experimental process, including the injection of the first fluid medium 51.

[0053] The temperature sensor and pressure sensor can be embedded in the inner wall of the upper top shell 11 and the lower base 12; in the second mounting cavity, the temperature sensor and pressure sensor can also be set on the surface of the rock sample 30 or close to the rock sample 30 to obtain more realistic simulated environmental data of the rock sample 30.

[0054] In some embodiments, the data acquisition module further includes a computer 92, which is connected to various temperature and pressure sensors via a data acquisition cable 91 to acquire and display detection data in real time for reference by experimental personnel.

[0055] It should be noted that if the second fluid medium 61 is a water-based medium such as deionized water, the water-based medium is conductive and may cause a short circuit in the drive module when it enters the first mounting cavity. Furthermore, when the drive module is running, the rotation of the output shaft 24 and the drill rod 71 will have a certain agitating effect, causing the nearby fluid medium to flow, which could also pose a risk of the second fluid medium 61 entering the first mounting cavity.

[0056] To address the aforementioned problems, according to some embodiments of the present invention, the first fluid medium 51 and the second fluid medium 61 fill the sealed cavity, and a portion of the first fluid medium 51 fills the second mounting cavity; a medium interface is formed between the first fluid medium 51 and the second fluid medium 61, the medium interface being formed within the second mounting cavity and spaced apart from the intermediate partition 13. In this embodiment, by setting the medium interface of the first fluid medium 51 and the second fluid medium 61 within the second mounting cavity and maintaining a certain distance from the intermediate partition 13, the second fluid medium can be prevented from flowing into the first mounting cavity due to agitation when the output shaft 24 and drill rod 71 rotate, thus providing a certain degree of protection for the drive module.

[0057] According to some embodiments of the present invention, the feed assembly includes a feed cylinder 73 and a feed pump 74. The output end of the feed cylinder 73 is connected to a rock sample 30 to facilitate axial movement of the rock sample 30 along the drill pipe 71. The feed pump 74 is connected to the feed cylinder 73 via a feed pipe 75 to facilitate supplying a power medium to the feed cylinder 73. In this embodiment, the power medium is supplied to the feed cylinder 73 by the feed pump 74, causing the feed cylinder 73 to output power to the rock sample 30, thereby moving the rock sample 30. The feed assembly of this embodiment has high load-bearing capacity, high temperature resistance, high control precision, low control difficulty, and stable control process.

[0058] In some embodiments, the feed cylinder 73 adopts a high-strength metal composite structure seal, with the inner layer being a thin-walled nickel-based alloy bellows and the outer layer being a hard alloy end face sealing ring.

[0059] In some embodiments, the feed cylinder 73 is disposed on the bottom inner wall of the lower base 12, and the lower base 12 has an installation hole that allows the feed oil pipe 75 to pass through. The feed oil pipe 75 is connected to the installation hole by a threaded connection to achieve a sealing effect.

[0060] It should be noted that the second fluid medium 61 forms a high pressure in the second mounting cavity. At the beginning of the experiment, the feed assembly of the above embodiment uses the feed pump 74 to initially pressurize the feed cylinder 73 to maintain the internal and external pressure balance to prevent leakage at the seal.

[0061] In addition, in the existing technology, the shaft of the drive motor is usually assembled by ball bearings. However, traditional rolling bearings rely on grease or lubricating oil to maintain operation. High temperature and high pressure environment will cause the lubricating medium to carbonize or decrease in viscosity, resulting in increased bearing wear and affecting the operation of the drive motor.

[0062] To address the aforementioned problems, according to some embodiments of the present invention, a solid self-lubricating bearing 25 is provided within the through hole 131, and the output shaft 24 is connected to the inner ring of the solid self-lubricating bearing 25, such as... Figure 3 As shown. In this embodiment, the solid self-lubricating bearing 25 provides lubrication by continuously releasing embedded solid lubricant during relative sliding within the bearing. Under high temperature and high pressure conditions, no additional lubricating grease is required, avoiding the problem of lubricant failure under these conditions. Compared to traditional ball bearings, this significantly extends the maintenance cycle. Furthermore, both ends of the output shaft 24 are supported and mounted using the solid self-lubricating bearing 25.

[0063] According to some embodiments of the present invention, the housing is provided with a safety valve 17. In this embodiment, by providing the safety valve 17, when the internal pressure of the sealed cavity exceeds a preset value, the internal pressure can be reduced by means of medium release, etc., to avoid the danger of explosion, leakage or other hazards caused by excessive internal pressure.

[0064] In some embodiments, the housing is formed with a vent hole, and a vent bolt 18 is installed at the vent hole to facilitate the discharge of the fluid medium after the experiment.

[0065] According to some embodiments of the present invention, the high-temperature and high-pressure drilling rock-breaking simulation experimental device further includes a clamping module 40, which is disposed within the second mounting cavity to limit the position of the rock sample 30. In this embodiment, the clamping module 40 can be disposed on the bottom inner wall of the lower base 12, thereby limiting the position of the rock sample 30. The clamping module 40 applies a clamping force to the rock sample 30 perpendicular to the axial direction of the drill rod 71, limiting and maintaining its stable position without affecting the movement of the rock sample 30 along the axial direction of the drill rod 71. Furthermore, the clamping module 40 does not affect the pressure applied to the rock sample 30 by the second fluid medium 61.

[0066] The method of using the high-temperature and high-pressure drilling rock-breaking simulation experimental device of the present invention is as follows:

[0067] S1. Initial preparation: Before use, adjust the lower base 12 to a horizontal position and place the rock sample 30 of a specific size in the clamping module 40 for fixation; assemble the drive module, drilling module and other structures, and align the upper shell 11, middle partition 13 and lower base 12; use fixing bolts 14 to connect and tighten, so that the upper shell 11, middle partition 13 and lower base 12 meet the sealing requirements;

[0068] S2, Chamber Injection: Start the second high-pressure pump 63 and inject a certain amount of deionized water into the second mounting cavity through the high-pressure pipe 62; start the first high-pressure pump 54 and inject silicone oil into the first mounting cavity through the medium circulation pipeline until the silicone oil fills the entire first mounting cavity and flows into the second mounting cavity, ensuring that the contact interface between the silicone oil and the deionized water is located in the second mounting cavity;

[0069] S3. System pressurization: The silicone oil and deionized water in the sealing cavity are pressurized by the first high-pressure pump 54 and the second high-pressure pump 63 respectively; the pressure data is monitored in real time by the data acquisition module; at the same time, the feed pump 74 is started to pressurize the feed cylinder 73 to maintain the pressure balance between its internal oil chamber and the second mounting chamber; when the pressure in the sealing cavity reaches the set value P0, the pressurization is stopped.

[0070] S4. Heating: The electromagnetic coil 80 is energized to heat the deionized water in the second mounting cavity. At the same time, the temperature data of the deionized water is monitored in real time by the data acquisition module to ensure that the deionized water reaches the set temperature T0 and maintains that temperature. During the heating process of the deionized water, the silicone oil in the first mounting cavity is circulated and cooled by the radiator 55. The data acquisition module monitors the temperature data of the silicone oil in real time to ensure that the temperature of the silicone oil is below 150℃.

[0071] S5. Drilling: Power is supplied to the drive motor by power supply 23. When the drive motor starts and reaches the rated speed, the feed pump 74 is pressurized and hydraulic pressure is supplied to the feed cylinder 73 through the feed oil pipe 75, pushing the rock sample 30 to move upward gradually, completing the drilling operation and realizing rock breaking.

[0072] S6. Depressurization: After drilling is completed, disconnect the power supply 23 and stop pressurizing the silicone oil and deionized water; after the device and the silicone oil and deionized water inside have completely cooled down, depressurize the silicone oil and deionized water inside the sealed cavity.

[0073] S7. Discharge and Recycling: The silicone oil and deionized water inside the sealed cavity are discharged through the drain bolt 18 and collected; the collected silicone oil and deionized water are precipitated and filtered to obtain the rock cuttings generated during drilling.

[0074] S8. Disassembly and sampling: Remove the fixing bolts 14 that connect the upper top shell 11, the middle partition plate 13 and the lower base 12, and separate the upper top shell 11, the middle partition plate 13 and the lower base 12; after disassembly, the rock sample 30 after drilling and the worn drill bit 72 can be obtained.

[0075] S9. Analysis: The rock cuttings produced in the experiment, the rock sample 30 after the experiment, and the worn drill bit 72 were observed, processed, and analyzed to study the process of drilling and rock breaking and the situation of rock fragmentation, so as to provide reliable theoretical and experimental references for actual construction.

[0076] The following experiments were conducted using the high-temperature and high-pressure drilling rock-breaking simulation experimental device of the present invention:

[0077] Experiment 1: Rock sample 30 is granite with a diameter of 200 mm and a height of 150 mm; the target temperature is 240℃ and the target pressure is 130 MPa; the burst pressure of safety valve 17 is set to 145 MPa; the safe operating temperature of the drive module is ≤150℃.

[0078] (1) Assembly and sealing of the device: After the internal structure of the sealing cavity is assembled, 8 sets of M24 high-strength bolts are used to tighten them with a preload torque of 280 N·m to achieve a sealed connection between the upper shell 11, the middle partition plate 13 and the lower base 12; the sealing performance is confirmed by detecting the compression of the metal O-ring and the graphite spiral wound gasket, and verifying that there is no mechanical damage to the sealing surface.

[0079] (2) Dual-medium injection: 18.5L of high-purity deionized water is injected into the second mounting cavity; 21.5L of phenylsiloxane silicone oil is injected into the first mounting cavity; the contact interface between the silicone oil and the deionized water is confirmed to be stable at 20mm below the intermediate partition 13 by the injection volume.

[0080] (3) Pressurization: Start the first high-pressure pump 54, the second high-pressure pump 63 and the feed pump 74 to achieve synchronous pressurization of the three pumps. The second high-pressure pump 63 pressurizes at a rate of 8MPa / min, the first high-pressure pump 54 compensates for pressure fluctuations in real time, and the feed pump 74 pressurizes to maintain the pressure balance of the feed cylinder 73. Finally, the pressure in the sealing cavity is stabilized to 130MPa.

[0081] (4) Heating: Apply 9.2kW / 20kHz AC current to electromagnetic coil 80 to heat deionized water through eddy current effect; adopt a segmented temperature control strategy during heating: the heating rate is 15℃ / min when below 200℃, and the heating rate is reduced to 5℃ / min in the 200-240℃ range;

[0082] During the heating process, the power of the electromagnetic coil 80 is dynamically adjusted based on the real-time temperature data fed back by the temperature sensor, ultimately bringing the temperature of the deionized water to 239.6℃.

[0083] During the heating process, the first high-pressure pump 54 maintains a flow rate of 25L / min to drive the silicone oil through the radiator 55; the peak temperature of the silicone oil was measured to be 142.3℃ during the experiment, which meets the control requirement of ≤150℃;

[0084] (5) Drilling process execution: Three-phase 380V power supply 23 is supplied to the drive module, and the speed of the motor rotor 22 is stabilized at 1800rpm; the feed pump 74 boosts the output of hydraulic oil and delivers it to the feed cylinder 73 through the feed oil pipe 75. The feed cylinder 73 lifts the rock sample 30 at a rate of 0.6mm / min; the drill bit 72 performs the crushing operation under axial load;

[0085] (6) Experiment termination and sample recovery: When the drilling depth reaches 30mm, the power supply of the drive motor 23 is cut off and the medium pressurization is stopped; when the device cools down to below 80℃, the drain bolt 18 is opened to discharge the medium. The drain bolt 18 is equipped with a 50μm filter screen to effectively intercept rock cuttings; the discharged medium is collected and filtered through a 0.1μm filter membrane to obtain rock cuttings; after removing the fixing bolt 14, the shell structure is separated and the drill bit 72 and the drilled rock sample 30 are taken out.

[0086] The direct experimental results are as follows: the wear on the back face of drill bit 72 is 0.32 mm, and the amount of rock cuttings is 183.5 g.

[0087] Experiment 2: Rock sample 30 was a granite sample with a diameter of 200 mm and a height of 150 mm; drill bit 72 was a diamond-encrusted drill bit with a diameter of 50 mm; the target temperature was 260℃ and the target pressure was 150 MPa; the burst pressure of safety valve 17 was set to 165 MPa; the safe operating temperature of the drive module was ≤150℃.

[0088] (1) Assembly and sealing of the device: After the internal structure of the sealing cavity is assembled, 8 sets of M24 high-strength bolts are used to tighten them with a preload torque of 280 N·m to achieve a sealed connection between the upper shell 11, the middle partition plate 13 and the lower base 12; the sealing performance is confirmed by detecting the compression of the metal O-ring and the graphite spiral wound gasket, and verifying that there is no mechanical damage to the sealing surface.

[0089] (2) Dual-medium injection: 18.5L of high-purity deionized water is injected into the second mounting cavity; 21.5L of phenylsiloxane silicone oil is injected into the first mounting cavity; the contact interface between the silicone oil and the deionized water is confirmed to be stable at 20mm below the intermediate partition 13 by the injection volume.

[0090] (3) Pressurization: Start the first high-pressure pump 54, the second high-pressure pump 63 and the feed pump 74 to achieve synchronous pressurization of the three pumps. The second high-pressure pump 63 first raises the deionized water to 100MPa at a rate of 5MPa / min, and then raises the deionized water to 150MPa at a rate of 2MPa / min. The first high-pressure pump 54 compensates for pressure fluctuations in real time, and the feed pump 74 pressurizes to maintain the pressure balance of the feed cylinder 73. Finally, the pressure in the sealing cavity is stabilized to 150MPa.

[0091] (4) Heating: Apply 10.5kW / 25kHz AC current to the electromagnetic coil 80 to heat the deionized water through the eddy current effect; a segmented temperature control strategy is adopted during heating: the heating rate is 15℃ / min when the temperature is below 200℃, and the heating rate is reduced to 5℃ / min in the range of 200-260℃.

[0092] During the heating process, the power of the electromagnetic coil 80 is dynamically adjusted based on the real-time temperature data fed back by the temperature sensor, so that the temperature of the deionized water reaches 259.8℃.

[0093] During the heating process, the first high-pressure pump 54 maintains a flow rate of 28L / min to drive the silicone oil through the radiator 55; the peak temperature of the silicone oil was measured to be 145.1℃ during the experiment, which meets the control requirement of ≤150℃;

[0094] (5) Drilling process execution: Three-phase 380V power supply 23 is supplied to the drive module, and the speed of the motor rotor 22 is stabilized at 1600rpm; the feed pump 74 boosts the output of hydraulic oil and delivers it to the feed cylinder 73 through the feed oil pipe 75. The feed cylinder 73 lifts the rock sample 30 at a rate of 0.8mm / min; the impregnated diamond drill bit 72 performs the crushing operation under axial load;

[0095] (6) Termination of experiment and sample recovery: When the drilling depth reaches 35mm, the power supply of the drive motor 23 is cut off and the medium pressurization is stopped; the device is naturally cooled to below 70℃, the drain bolt 18 is opened to discharge the medium. The drain bolt 18 is equipped with a 50μm filter screen to effectively intercept rock cuttings; the discharged medium is collected and filtered through a 0.1μm filter membrane to obtain rock cuttings; after removing the fixing bolt 14, the shell structure is separated and the drill bit 72 and the drilled rock sample 30 are taken out.

[0096] The direct experimental results are as follows: the back face wear of drill bit 72 is 0.28 mm, and the rock cuttings are 205.3 g.

[0097] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0098] In the description of this invention, "first feature" and "second feature" may include one or more of the features.

[0099] In the description of this invention, "a plurality of" means two or more.

[0100] In the description of this invention, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0101] In the description of this invention, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0102] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0103] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A high-temperature and high-pressure drilling rock-breaking simulation experimental device, characterized in that, include: A housing having a sealed cavity inside, and the housing having a middle partition plate that defines the sealed cavity as a first mounting cavity and a second mounting cavity; A rock sample, wherein the rock sample is disposed within the second mounting cavity; A drive module is disposed in the first mounting cavity, and the intermediate partition has a through hole, through which the output shaft of the drive module extends into the second mounting cavity; A drilling module, comprising a drill rod and a feed assembly, wherein the drill rod is connected to the output shaft and a drill bit is provided at the end of the drill rod; the drill rod is axially aligned with the rock sample, and the feed assembly is connected to the rock sample and adapted to drive the rock sample to move in a direction close to the drill rod; A first pressure module is connected to the first mounting cavity to circulate and deliver a first fluid medium into the first mounting cavity; and the first pressure module includes a first high-pressure pump and a radiator, the first high-pressure pump being adapted to pressurize the first fluid medium and the radiator being adapted to cool the first fluid medium. A second pressure module is connected to the second mounting cavity to deliver a second fluid medium into the second mounting cavity; and the second pressure module includes a second high-pressure pump adapted to pressurize the second fluid medium. A heating module is disposed in the housing to be adapted to heat the second fluid medium.

2. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 1, characterized in that, The housing includes an upper top shell and a lower base, with an intermediate partition disposed between the upper top shell and the lower base. A first sealing element is disposed between the intermediate partition and the upper top shell, and a second sealing element is disposed between the intermediate partition and the lower base.

3. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 2, characterized in that, Both the upper shell and the lower base are constructed as double-walled structures; and a structural gap is formed inside the lower base, which is filled with heat-insulating material.

4. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 2, characterized in that, The heating module includes an electromagnetic coil disposed at the bottom of the lower base to heat the second fluid medium.

5. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 1, characterized in that, Also includes: A temperature sensor, wherein at least two temperature sensors are configured, and the two temperature sensors are respectively disposed in the first mounting cavity and the second mounting cavity, so as to be suitable for detecting the temperature of the first fluid medium and the second fluid medium; A pressure sensor, wherein at least one pressure sensor is configured to be disposed within the second mounting cavity to be adapted to detect the pressure of the second fluid medium.

6. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 1, characterized in that, The first fluid medium and the second fluid medium fill the sealing cavity, and a portion of the first fluid medium fills the second mounting cavity; a medium interface is formed between the first fluid medium and the second fluid medium, the medium interface is formed in the second mounting cavity, and is spaced apart from the intermediate partition.

7. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 1, characterized in that, The feed assembly includes: A feed cylinder, the output end of which is connected to the rock sample, is adapted to push the rock sample to move axially along the drill rod; A feed pump is connected to the feed cylinder via a feed oil pipe to deliver a power medium to the feed cylinder.

8. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 1, characterized in that, A solid self-lubricating bearing is installed inside the through hole, and the output shaft is connected to the inner ring of the solid self-lubricating bearing.

9. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 1, characterized in that, The housing is equipped with a safety valve.

10. The high-temperature and high-pressure drilling rock-breaking simulation experimental device according to claim 1, characterized in that, Also includes: A clamping module is disposed within the second mounting cavity to limit the position of the rock sample.

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