High-temperature and high-pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in separated bins and method thereof

Abstract

The invention provides a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system capable of loading a plurality of samples in different bins, which comprises a fracturing test bin arranged in a thermal insulation bin, a computer display, control and storage system is arranged outside the fracturing test bin, and the fracturing test bin is controlled by signals of a high-temperature heating and control system, an axial pressure loading and control system, a confining pressure loading and control system, a fracturing fluid injection pump and a control system; the computer display, control and storage system is respectively in communication connection with the high-temperature heating and control system, the axial pressure loading and control system, the confining pressure loading and control system, the fracturing fluid injection pump and control system as well as an acoustic emission monitoring system and an injection pressure monitoring system which are arranged in the fracturing test bin; the fracturing test cabins are arranged in different cabins; the system comprises a high-temperature and high-pressure triaxial test method and a high-temperature and high-pressure hydraulic fracturing test method. The device has the advantages that the test efficiency is improved, the test period is shortened, a plurality of rock core samples can be tested at the same time, and a visual contrast test can be formed.

Description

Technical Field

[0001] The present invention relates to the technical field of hot dry rock physical mechanics research, and in particular to a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system and method for loading multiple samples in separate compartments. Background Art

[0002] Under the influence of air pollution and global warming caused by fossil fuels, countries around the world have begun to transform to a renewable and clean energy structure. Hot dry rocks are usually buried thousands of meters deep, with a temperature greater than 200°C. They contain rich geothermal energy and have the advantages of stable and continuous energy supply. The development of hot dry rocks usually adopts an enhanced geothermal system, which injects high-pressure fluid into the hot dry rocks through drilling, and expands the joints and fissures of the rock mass through pressure to form a fracture seepage heat exchange network. The connectivity and formation characteristics of the fracture network have a huge impact on the exploitation of geothermal resources. Therefore, it is necessary to conduct high-temperature and high-pressure rock triaxial and hydraulic fracturing tests to better study the physical and mechanical properties of hot dry rock under high temperature and high pressure conditions and the behavior of generating fractures under hydraulic fracturing stimulation.

[0003] At present, hydraulic fracturing experiments can only be carried out on one sample, and because high temperature conditions need to be set, the heating and cooling time is long, the test cycle is long, and it is also impossible to directly form a comparative experiment of stepped high temperature and high pressure. Summary of the invention

[0004] The purpose of the present invention is to provide a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system and method for loading multiple samples in separate compartments, which can improve test efficiency, shorten test cycle, test multiple core samples at the same time and form an intuitive comparative test.

[0005] In order to achieve the above object, the present invention is implemented by the following technical solutions: A high-temperature and high-pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in separate compartments, comprising a fracturing test compartment, wherein the fracturing test compartment is placed in a thermal insulation compartment, the fracturing test compartment is externally provided with a computer display, control and storage system and is controlled by signals from a high-temperature heating and control system, an axial pressure loading and control system, a confining pressure loading and control system, and a fracturing fluid injection pump and control system, wherein the computer display, control and storage system is respectively communicated with the high-temperature heating and control system, the axial pressure loading and control system, the confining pressure loading and control system, the fracturing fluid injection pump and control system, and an acoustic emission monitoring system and an injection pressure monitoring system in the fracturing test compartment; the fracturing test compartment is arranged in separate compartments.

[0006] Furthermore, the fracturing test chamber is provided with a compartment grid, and the compartment grid includes a grid fixed axis and two vertically arranged compartment plates, each compartment plate takes the fixed axis as a central axis and abuts against the inner wall of the fracturing test chamber.

[0007] Furthermore, the axial pressure loading and control system is divided into four compartment axial pressure loading and control systems according to the number of compartments, which respectively control the axial pressure loading of each single compartment; the confining pressure loading and control system is divided into four compartment X-direction confining pressure loading and control systems and four compartment Y-direction confining pressure loading and control systems according to the number of compartments, which respectively control the confining pressure loading of each single compartment in the X direction and the Y direction.

[0008] Furthermore, a cooling fan is provided at the opening and closing position of the thermal insulation chamber, which can quickly reduce the temperature of the fracturing test chamber.

[0009] A high temperature and high pressure rock triaxial test method for loading multiple specimens in separate compartments comprises the following steps: S1) Processing samples The sample is processed into a rectangular parallelepiped by a rock sample cutter to make it conform to the size of the fracturing compartment; S2) Place the sample Place the four processed samples a, b, c, and d into the fracturing test chamber in sequence, with the two sides of the samples close to the chamber plates; S3) Fix the sample The computer display, control and storage system is used to sequentially control the axial pressure loading and control system of each single chamber to push the axial steel plate to provide axial pressure, control the X-direction confining pressure loading and control system of the single chamber to provide X-direction confining pressure, and control the Y-direction confining pressure loading and control system of the single chamber to provide Y-direction confining pressure, thereby applying a certain axial pressure and confining pressure to the specimen in advance for fixing; S4) For sample a, heat it through the high temperature heating and control system, and use the computer display, control and storage system to display and control the heating to the required test temperature Ta of sample a; S5) For sample a, the single-chamber X-direction confining pressure loading and control system provides the X-direction confining pressure, the single-chamber Y-direction confining pressure loading and control system provides the Y-direction confining pressure, and the computer display, control and storage system is used to display and control the test confining pressure Pa required for sample a; S6) For specimen a, the axial steel plate is pushed to provide axial pressure through the single-chamber axial pressure loading and control system until specimen a is destroyed; S7) if the test temperature does not need to be changed, repeat step S5), apply confining pressure Pb to sample b, and then repeat step S6); if the test temperature needs to be changed, repeat step S4), heat sample b to temperature Tb, repeat step S5), apply confining pressure Pb to sample b, and then repeat step S6); Repeat the above steps for samples c and d in turn; S8) After the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded from the axial pressure and confining pressure to normal pressure, and then the heat insulation chamber is opened, the temperature of the test chamber is lowered to normal temperature by a cooling fan, and then the fracturing test chamber is opened to take out the sample; S9) All test parameters and data are summarized and stored through the computer display, control and storage system, and analyzed and processed using the built-in software to obtain the test results required for the high temperature and high pressure triaxial test.

[0010] Furthermore, in step S7), the test may assemble four test specimens a, b, c, d, set four test temperatures Ta, Tb, Tc, Td from low to high, and load four confining pressure conditions Pa, Pb, Pc, Pd, respectively, to form a comparative test.

[0011] A high temperature and high pressure hydraulic fracturing test method for loading multiple samples in separate compartments comprises the following steps: S1) Processing samples The sample is processed into a rectangular shape by a rock sample cutting machine, which meets the size of the fracturing compartment, and a hole is drilled along the Z direction, i.e., the direction of axial pressure application, until the middle of the sample, and a prefabricated fracturing steel pipe is buried. The steel pipe is tightly connected to the drill hole through a sealant; S2) Place the sample Place the four processed samples a, b, c, and d into the fracturing test chamber in sequence, with the two sides of the samples close to the chamber plates, and connect the fracturing fluid injection pump and control system to the fracturing steel pipe of the samples; S3) Fix the sample The computer display, control and storage system is used to sequentially control the axial pressure loading and control system of each single chamber to push the axial steel plate to provide axial pressure, control the X-direction confining pressure loading and control system of the single chamber to provide X-direction confining pressure, and control the Y-direction confining pressure loading and control system of the single chamber to provide Y-direction confining pressure, thereby applying a certain axial pressure and confining pressure to the specimen in advance for fixing; S4) For sample a, heat it through the high temperature heating and control system, and use the computer display, control and storage system to display and control the heating to the required test temperature Ta of sample a; S5) For sample a, the single-chamber X-direction confining pressure loading and control system provides the X-direction confining pressure, the single-chamber Y-direction confining pressure loading and control system provides the Y-direction confining pressure, and the computer display, control and storage system is used to display and control the test confining pressure Pa required for sample a; S6) For sample a, the axial pressure is provided by the single-bin axial pressure loading and control system, and the computer display, control and storage system is used to display and control the test axial pressure Pa' required for sample a; S7) injecting fracturing fluid into sample a at a rate Va through the fracturing fluid injection pump and control system until sample a is destroyed, monitoring and recording the injected pressure data through the injection pressure monitoring system, and using the computer display, control and storage system to display and control the required injection rate Va and injection pressure Pa of sample a”; S8) If the test temperature does not need to be changed, repeat steps S5) and S6), apply confining pressure Pb and axial pressure Pb' to sample b, and then repeat step S7 at injection rate Vb); If the test temperature needs to be changed, repeat step S4), heat sample b to temperature Tb, and then repeat steps S5) and S6), apply confining pressure Pb and axial pressure Pb' to sample b, and then repeat step S7 at injection rate Vb); Repeat the above steps for samples c and d in turn; S9) After the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded from the axial pressure and confining pressure to normal pressure, and then the heat insulation chamber is opened, the temperature of the test chamber is lowered to normal temperature by a cooling fan, and then the fracturing test chamber is opened to take out the sample; S10) All test parameters and data are summarized and stored through the computer display, control and storage system, and analyzed and processed using the built-in software to obtain the test results required for the high temperature and high pressure hydraulic fracturing test.

[0012] Furthermore, in step S8), the test can assemble four specimens a, b, c, and d, set four test temperatures Ta, Tb, Tc, and Td from low to high, respectively, and load four confining pressure conditions Pa, Pb, Pc, and Pd and four axial pressure conditions Pa', Pb', Pc', and Pd', respectively, and set four injection velocities Va, Vb, Vc, and Vd to form a comparative test.

[0013] Compared with the prior art, the present invention has the following advantages: The present invention discloses a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system and method for loading multiple samples in separate compartments, which improves test efficiency, shortens the test cycle, can test multiple core samples at the same time and form an intuitive comparative test. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the system structure of the present invention.

[0015] Figure 2 It is a schematic diagram of the structural decomposition of the fracturing test chamber of the present invention.

[0016] Figure 3 It is a schematic diagram of the compartment grid structure of the present invention.

[0017] Figure 4 It is a schematic diagram of the single-chamber structure of the fracturing device of the present invention.

[0018] Figure numerals: 1. Fracturing fluid injection pump and control system; 2. High-temperature heating and control system; 3. Fracturing test chamber; 31. Sub-compartment axial pressure loading and control system; 311. Single-compartment axial pressure loading and control system; 32. Sub-compartment X-direction confining pressure loading and control system; 321. Single-compartment X-direction confining pressure loading and control system; 33. Sub-compartment grid; 331. Grid fixing axis; 332. Sub-compartment plate; 34. Sub-compartment Y-direction confining pressure loading and control system; 341. Single-compartment Y-direction confining pressure loading and control system; 35. Fracturing single chamber; 4. Axial pressure loading and control system; 5. Confining pressure loading and control system; 6. Injection pressure monitoring system; 7. Acoustic emission monitoring system; 8. Computer display, control and storage system; 9. Thermal insulation chamber; 10. Air cooler. DETAILED DESCRIPTION

[0019] The embodiments of the present invention are described in further detail below in conjunction with the accompanying drawings.

[0020] like Figure 1 As shown, a high temperature and high pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in compartments includes a fracturing test compartment 3, which is placed in a heat-insulating compartment 9 to avoid heat loss, accelerate the heating speed, and ensure the safety of the test through insulation. The fracturing test compartment 3 is externally equipped with a computer display, control and storage system 8 and is controlled by signals from a high temperature heating and control system 2, an axial pressure loading and control system 4, a confining pressure loading and control system 5, and a fracturing fluid injection pump and control system 1. The computer display, control and storage system 8 is respectively connected to the high temperature heating and control system 2, the axial pressure loading and control system 4, the confining pressure loading and control system 5, the fracturing fluid injection pump and control system 1, and the acoustic emission monitoring system 7 and the injection pressure monitoring system 6 provided in the fracturing test compartment 3 to change the temperature and pressure conditions in the fracturing test compartment 3, control the injection of fracturing fluid, monitor and record the injection pressure and acoustic emission events; the computer display, control and storage system 8 can display and store the changes of various parameters in real time, control the relevant systems to change the parameters, and use the built-in processing software to process the test and monitoring data. The opening and closing position of the heat-insulating chamber 9 is provided with a cooling fan 10 , which can quickly reduce the temperature of the fracturing test chamber 3 .

[0021] Specifically, the fracturing fluid injection pump and control system 1 is composed of a fracturing fluid storage tank, a fracturing fluid injection pump, an injection pump control system, and a fluid injection pipe. The fracturing fluid storage tank is filled with water and supercritical CO. 2A variety of fracturing fluids, such as 100% molten steel, ... The confining pressure loading and control system 5 is an X and Y direction confining pressure system, which is composed of a servo hydraulic press and X and Y direction steel plates. The servo hydraulic press is located outside the fracturing test chamber 3 and is divided into four compartment loading modules, which can provide different confining pressures for the four compartments respectively, conduct triaxial tests or provide the confining pressure required for hydraulic fracturing tests, and record them. The injection pressure monitoring system 6 is a pressure probe arranged at the injection pipe of the fracturing fluid injection pump and control system 1 near the prefabricated fracturing steel pipe, which can monitor and record the injection pressure. The acoustic emission probe of the acoustic emission monitoring system 7 is arranged in the fracturing test chamber 3, which can monitor the sound waves generated by the deformation and destruction of the sample throughout the whole process, locate the rupture and reflect the process and severity of the crack formation.

[0022] like Figure 2 , 3 As shown in FIG. 4 , the fracturing test chamber 3 is divided into compartments, and the fracturing test chamber 3 is provided with a compartment grid 33. The compartment grid 33 includes a grid fixed axis 331 and two vertically arranged compartment plates 332. Each compartment plate 332 takes the fixed axis 331 as the center axis and abuts against the inner wall of the fracturing test chamber 3, that is, the fracturing test chamber 3 is divided into four single fracturing chambers 35.

[0023] The axial pressure loading and control system 4 is divided into four compartment axial pressure loading and control systems 41 according to the number of compartments, which respectively control the axial pressure loading of each fracturing compartment 35; the confining pressure loading and control system 5 is divided into four compartment X-direction confining pressure loading and control systems 32 and four compartment Y-direction confining pressure loading and control systems 34 according to the number of compartments, which respectively control the confining pressure loading of each single compartment in the X direction and the Y direction. The establishment of the axial pressure and confining pressure is provided by the servo motor pushing the steel plate. The voltage signal is converted into torque and speed to drive the control object, and the position accuracy is very accurate. During the pressurization and fracturing process, the acoustic emission monitoring system 7 monitors the sound waves generated by the deformation and destruction of the sample throughout the process, locates the rupture and reflects the process and severity of the crack formation; the injection pressure monitoring system 6 monitors the changes in the injection pressure throughout the process. Example

[0024] A high temperature and high pressure rock triaxial test method for loading multiple specimens in separate compartments comprises the following steps: S1) Processing samples The sample is processed into a rectangular parallelepiped by a rock sample cutter to make it conform to the size of the fracturing compartment; S2) Place the sample Place the four processed samples a, b, c, and d into the fracturing chamber 35 in sequence, with the two sides of the samples close to the chamber plate 332; S3) Fix the sample The computer display, control and storage system 8 sequentially controls the axial pressure loading and control system 311 of each single chamber to push the axial steel plate to provide axial pressure, controls the X-direction confining pressure loading and control system 321 of the single chamber to provide X-direction confining pressure, and controls the Y-direction confining pressure loading and control system 341 of the single chamber to provide Y-direction confining pressure, thereby applying a certain axial pressure and confining pressure to the sample in advance for fixing; S4) heating the sample a by the high temperature heating and control system 2, and using the computer display, control and storage system 8 to display and control the heating to the required test temperature Ta of the sample a; S5) For sample a, the single-chamber X-direction confining pressure loading and control system 321 provides X-direction confining pressure, the single-chamber Y-direction confining pressure loading and control system 341 provides Y-direction confining pressure, and the computer display, control and storage system 8 is used to display and control the test confining pressure Pa required for sample a; S6) For sample a, the axial steel plate is pushed to provide axial pressure through the single-chamber axial pressure loading and control system 311 until sample a is destroyed; S7) if the test temperature does not need to be changed, repeat step S5), apply confining pressure Pb to sample b, and then repeat step S6); if the test temperature needs to be changed, repeat step S4), heat sample b to temperature Tb, repeat step S5), apply confining pressure Pb to sample b, and then repeat step S6); Repeat the above steps for samples c and d in turn; S8) After the test is completed, the axial pressure loading and control system 4 and the confining pressure loading and control system 5 are unloaded from the axial pressure and the confining pressure to normal pressure, and then the heat insulation chamber 9 is opened, and the temperature of the fracturing test chamber 3 is lowered to normal temperature by the cooling fan 10, and then the fracturing test chamber 3 is opened to take out the sample; S9) All test parameters and data are summarized and stored through the computer display, control and storage system 8, and analyzed and processed using built-in software to obtain the test results required for the high temperature and high pressure triaxial test.

[0025] Furthermore, in step S7), the test may assemble four test specimens a, b, c, d, set four test temperatures Ta, Tb, Tc, Td from low to high, and load four confining pressure conditions Pa, Pb, Pc, Pd, respectively, to form a comparative test. Example

[0026] A high temperature and high pressure hydraulic fracturing test method for loading multiple samples in separate compartments comprises the following steps: S1) Processing samples The sample is processed into a rectangular shape by a rock sample cutting machine, which meets the size of the fracturing compartment, and a hole is drilled along the Z direction, i.e., the direction of axial pressure application, until the middle of the sample, and a prefabricated fracturing steel pipe is buried. The steel pipe is tightly connected to the drill hole through a sealant; S2) Place the sample Place the four processed samples a, b, c, and d into the fracturing test chamber 3 in sequence, with the two sides of the samples close to the chamber plate 332, and connect the fracturing fluid injection pump and control system 1 to the fracturing steel pipe of the sample; S3) Fix the sample The computer display, control and storage system 8 sequentially controls the axial pressure loading and control system 311 of each single chamber to push the axial steel plate to provide axial pressure, controls the X-direction confining pressure loading and control system 321 of the single chamber to provide X-direction confining pressure, and controls the Y-direction confining pressure loading and control system 341 of the single chamber to provide Y-direction confining pressure, thereby applying a certain axial pressure and confining pressure to the sample in advance for fixing; S4) heating the sample a by the high temperature heating and control system 2, and using the computer display, control and storage system 8 to display and control the heating to the required test temperature Ta of the sample a; S5) For sample a, the single-chamber X-direction confining pressure loading and control system 321 provides X-direction confining pressure, the single-chamber Y-direction confining pressure loading and control system 341 provides Y-direction confining pressure, and the computer display, control and storage system 8 is used to display and control the test confining pressure Pa required for sample a; S6) For sample a, the single-bin axial pressure loading and control system 311 provides axial pressure, and the computer display, control and storage system 8 is used to display and control the test axial pressure Pa' required for sample a; S7) injecting fracturing fluid into sample a at a speed Va through the fracturing fluid injection pump and control system 1 until sample a is destroyed, monitoring and recording the injected pressure data through the injection pressure monitoring system 6, and displaying and controlling the required injection speed Va and injection pressure Pa of sample a through the computer display, control and storage system 8; S8) If the test temperature does not need to be changed, repeat steps S5) and S6), apply confining pressure Pb and axial pressure Pb' to sample b, and then repeat step S7 at injection rate Vb); If the test temperature needs to be changed, repeat step S4), heat sample b to temperature Tb, and then repeat steps S5) and S6), apply confining pressure Pb and axial pressure Pb' to sample b, and then repeat step S7 at injection rate Vb); Repeat the above steps for samples c and d in turn; S9) After the test is completed, the axial pressure loading and control system 4 and the confining pressure loading and control system 5 are unloaded from the axial pressure and the confining pressure to normal pressure, and then the heat insulation chamber 9 is opened, and the temperature of the fracturing test chamber 3 is lowered to normal temperature by the cooling fan 10, and then the fracturing test chamber 3 is opened to take out the sample; S10) All test parameters and data are summarized and stored through the computer display, control and storage system 8, and analyzed and processed using built-in software to obtain the test results required for the high temperature and high pressure hydraulic fracturing test.

[0027] Furthermore, in step S8), the test can assemble four specimens a, b, c, and d, set four test temperatures Ta, Tb, Tc, and Td from low to high, respectively, and load four confining pressure conditions Pa, Pb, Pc, and Pd and four axial pressure conditions Pa', Pb', Pc', and Pd', respectively, and set four injection velocities Va, Vb, Vc, and Vd to form a comparative test.

[0028] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make four improvements and modifications without departing from the concept of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A high temperature and high pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in separate compartments, comprising a fracturing test compartment, characterized in that: The fracturing test chamber is placed in a thermal insulation chamber, the fracturing test chamber is equipped with an external computer display, control and storage system and is controlled by signals from a high-temperature heating and control system, an axial pressure loading and control system, a confining pressure loading and control system, and a fracturing fluid injection pump and control system. The computer display, control and storage system is respectively communicated with the high-temperature heating and control system, the axial pressure loading and control system, the confining pressure loading and control system, the fracturing fluid injection pump and control system, and the acoustic emission monitoring system and injection pressure monitoring system provided in the fracturing test chamber; the fracturing test chamber is arranged in separate chambers.

2. A high temperature and high pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in separate compartments according to claim 1, characterized in that: The fracturing test chamber is provided with a compartment grid, which includes a grid fixed axis and two vertically arranged compartment plates, each compartment plate takes the fixed axis as a central axis and abuts against the inner wall of the fracturing test chamber.

3. A high temperature and high pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in separate compartments according to claim 2, characterized in that: The axial pressure loading and control system is divided into four compartment axial pressure loading and control systems according to the number of compartments, which respectively control the axial pressure loading of each single compartment; the confining pressure loading and control system is divided into four compartment X-direction confining pressure loading and control systems and four compartment Y-direction confining pressure loading and control systems according to the number of compartments, which respectively control the confining pressure loading of each single compartment in the X direction and the Y direction.

4. A high temperature and high pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in separate compartments according to claim 1 or 3, characterized in that: The opening and closing position of the thermal insulation chamber is provided with a cooling fan, which can quickly reduce the temperature of the fracturing test chamber.

5. A high temperature and high pressure rock triaxial test method with multiple specimens loaded in separate compartments, characterized in that The steps include: S1) Processing samples The sample is processed into a rectangular parallelepiped by a rock sample cutter to make it conform to the size of the fracturing compartment; S2) Place the sample Place the four processed samples a, b, c, and d into the fracturing test chamber in sequence, with the two sides of the samples close to the chamber plates; S3) Fix the sample The computer display, control and storage system is used to sequentially control the axial pressure loading and control system of each single chamber to push the axial steel plate to provide axial pressure, control the X-direction confining pressure loading and control system of the single chamber to provide X-direction confining pressure, and control the Y-direction confining pressure loading and control system of the single chamber to provide Y-direction confining pressure, thereby applying a certain axial pressure and confining pressure to the specimen in advance for fixing; S4) For sample a, heat it through the high temperature heating and control system, and use the computer display, control and storage system to display and control the heating to the required test temperature Ta of sample a; S5) For sample a, the single-chamber X-direction confining pressure loading and control system provides the X-direction confining pressure, the single-chamber Y-direction confining pressure loading and control system provides the Y-direction confining pressure, and the computer display, control and storage system is used to display and control the test confining pressure Pa required for sample a; S6) For specimen a, the axial steel plate is pushed to provide axial pressure through the single-chamber axial pressure loading and control system until specimen a is destroyed; S7) if the test temperature does not need to be changed, repeat step S5), apply confining pressure Pb to sample b, and then repeat step S6); if the test temperature needs to be changed, repeat step S4), heat sample b to temperature Tb, repeat step S5), apply confining pressure Pb to sample b, and then repeat step S6); Repeat the above steps for samples c and d in turn; S8) After the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded from the axial pressure and confining pressure to normal pressure, and then the heat insulation chamber is opened, the temperature of the test chamber is lowered to normal temperature by a cooling fan, and then the fracturing test chamber is opened to take out the sample; S9) All test parameters and data are summarized and stored through the computer display, control and storage system, and analyzed and processed using the built-in software to obtain the test results required for the high temperature and high pressure triaxial test.

6. The high temperature and high pressure rock triaxial testing method with multiple specimens loaded in separate compartments according to claim 5 is characterized by: In step S7), the test can assemble four test specimens a, b, c, and d, set four test temperatures Ta, Tb, Tc, and Td from low to high, and load four confining pressure conditions Pa, Pb, Pc, and Pd, respectively, to form a comparative test.

7. A high temperature and high pressure hydraulic fracturing test method for loading multiple samples in separate compartments, characterized in that The steps include: S1) Processing samples The sample is processed into a rectangular shape by a rock sample cutting machine, which meets the size of the fracturing compartment, and a hole is drilled along the Z direction, i.e., the direction of axial pressure application, until the middle of the sample, and a prefabricated fracturing steel pipe is buried. The steel pipe is tightly connected to the drill hole through a sealant; S2) Place the sample Place the four processed samples a, b, c, and d into the fracturing test chamber in sequence, with the two sides of the samples close to the chamber plates, and connect the fracturing fluid injection pump and control system to the fracturing steel pipe of the samples; S3) Fix the sample The computer display, control and storage system is used to sequentially control the axial pressure loading and control system of each single chamber to push the axial steel plate to provide axial pressure, control the X-direction confining pressure loading and control system of the single chamber to provide X-direction confining pressure, and control the Y-direction confining pressure loading and control system of the single chamber to provide Y-direction confining pressure, thereby applying a certain axial pressure and confining pressure to the specimen in advance for fixing; S4) For sample a, heat it through the high temperature heating and control system, and use the computer display, control and storage system to display and control the heating to the required test temperature Ta of sample a; S5) For sample a, the single-chamber X-direction confining pressure loading and control system provides the X-direction confining pressure, the single-chamber Y-direction confining pressure loading and control system provides the Y-direction confining pressure, and the computer display, control and storage system is used to display and control the test confining pressure Pa required for sample a; S6) For sample a, the axial pressure is provided by the single-bin axial pressure loading and control system, and the computer display, control and storage system is used to display and control the test axial pressure Pa' required for sample a; S7) injecting fracturing fluid into sample a at a rate Va through the fracturing fluid injection pump and control system until sample a is destroyed, monitoring and recording the injected pressure data through the injection pressure monitoring system, and using the computer display, control and storage system to display and control the required injection rate Va and injection pressure Pa of sample a”; S8) If the test temperature does not need to be changed, repeat steps S5) and S6), apply confining pressure Pb and axial pressure Pb' to sample b, and then repeat step S7 at injection rate Vb); If the test temperature needs to be changed, repeat step S4), heat sample b to temperature Tb, and then repeat steps S5) and S6), apply confining pressure Pb and axial pressure Pb' to sample b, and then repeat step S7 at injection rate Vb); Repeat the above steps for samples c and d in turn; S9) After the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded from the axial pressure and confining pressure to normal pressure, and then the heat insulation chamber is opened, the temperature of the test chamber is lowered to normal temperature by a cooling fan, and then the fracturing test chamber is opened to take out the sample; S10) All test parameters and data are summarized and stored through the computer display, control and storage system, and analyzed and processed using the built-in software to obtain the test results required for the high temperature and high pressure hydraulic fracturing test.

8. A high temperature and high pressure hydraulic fracturing test method for loading multiple samples in separate compartments according to claim 7, characterized in that: In step S8), the test can assemble four specimens a, b, c, d, set four test temperatures Ta, Tb, Tc, Td from low to high, and load four confining pressure conditions Pa, Pb, Pc, Pd and four axial pressure conditions Pa', Pb', Pc', Pd', respectively, and set four injection speeds Va, Vb, Vc, Vd to form a comparative test.

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