Rock mass hydraulic fracturing test system and test method

Abstract

The present invention discloses a rock mass hydraulic fracturing test system and a test method thereof, which belongs to the technical field of test equipment. The system includes a control device, a liquid pressurizing device, a rotating imaging device, a fixed base and a protective cover. The protective cover is arranged on the fixed base, and the fixed base is arranged in the middle of the rotating imaging device through a bearing. A drilling device and a pressurizing connecting device are arranged in the protective cover, and a synchronous positioning mechanism is arranged inside the fixed base. The rotating imaging device, the drilling device and the pressurizing connecting device are all electrically connected to the control device. A test method based on the above system is also disclosed. The above rock mass hydraulic fracturing test system and a test method thereof are adopted, a drilling device and a synchronous positioning mechanism are added, the positioning and drilling processing of the rock sample are realized, and a rotating imaging device is arranged. During the test process, the drilling process and other processes, the image acquisition time interval can be set according to the test needs to observe the changes of the test rock sample.

Description

Technical Field

[0001] The invention relates to the technical field of testing equipment, and in particular to a rock mass hydraulic fracturing testing system and a testing method thereof. Background Art

[0002] Using the rock tensile strength obtained from the hydraulic fracturing test of hollow rock columns to replace the re-tensioning pressure to calculate the maximum horizontal principal stress is an important way to reduce the negative impact of the flexibility of the drill pipe test system. The patent with application number 201310449298.X discloses a multi-diameter core hydraulic fracturing tensile strength rapid testing machine, the testing machine is provided with a chassis, the chassis is provided with a hydraulic pressurization system, a rock sample loading and clamping system, a data acquisition system and an operation control system; the rock sample is a cylindrical rock sample, an axial blind hole is drilled on the upper bottom surface of the rock sample, and the rock sample can be prepared using four diameters of rock cores; a workbench is provided at the upper end of the trolley plate of the rock sample loading and clamping system, and the workbench is provided with a ball seat and a ball head for keeping the rock sample vertical; a protective cover, a hydraulic cylinder and a liquid injection block for pressurizing the blind hole of the rock sample are also provided on the workbench; the data acquisition system transmits the monitoring data to a computer for data analysis and processing to obtain the tensile strength value. The testing machine can quickly determine the quantitative value of the tensile strength of the rock sample. The testing principle and process are rigorous and reliable, the requirements for the rock sample are low, and the operation process and transportation method are simple.

[0003] In the actual testing process, it is necessary to drill a hole in the cylindrical rock sample before testing. The prior art has no imaging device, and thus cannot observe the change process of the tested rock sample, and the testing equipment has a single function. Summary of the invention

[0004] The purpose of the present invention is to provide a rock mass hydraulic fracturing test system and a test method thereof to solve the above technical problems.

[0005] To achieve the above-mentioned purpose, the present invention provides a rock hydraulic fracturing test system, including a control device and a liquid pressurizing device, and also including a rotating imaging device, a fixed base and a protective cover. The protective cover is arranged on the fixed base, and the fixed base is arranged in the middle of the rotating imaging device through a bearing. A drilling device and a pressurizing connecting device are arranged in the protective cover, and a synchronous positioning mechanism is arranged inside the fixed base. The rotating imaging device, the drilling device and the pressurizing connecting device are all electrically connected to the control device.

[0006] Preferably, the rotary imaging device comprises a turntable, and two mounting frames arranged opposite to each other are arranged on the circumferential side of the turntable, and lifting screws are arranged on both mounting frames, one of the lifting screws is arranged on the X-ray generator, and the other lifting screw is arranged on the detector, and the two lifting screws are connected by a synchronous belt, and one of the lifting screws is connected to a lifting drive motor fixed on the mounting frame;

[0007] The turntable, the lifting drive motor, the X-ray generator and the detector are all electrically connected to the control device.

[0008] Preferably, the fixed base is installed on the turntable through a bearing, and water guide grooves are distributed around the circumference of the fixed base. A drainage groove is arranged in the middle of the fixed seat, one end of the water guide groove is connected to the drainage groove, and the drainage groove is connected to a drainage pipe.

[0009] Preferably, the synchronous positioning mechanism comprises a fixed ring, at least three guide grooves are distributed on the circumference of the upper end surface of the fixed ring, a positioning rack is slidably arranged in the guide groove, a pressure sensor is arranged on the top of the positioning rack, the positioning rack is meshed with the driving gear on the fixed ring, a synchronous gear is arranged on the rotating shaft of the driving gear, the synchronous gear is meshed with the driving gear ring in the fixed ring, the driving gear ring is meshed with the gear on the output shaft of the positioning drive motor, and the positioning drive motor is installed on the fixed ring;

[0010] The pressure sensor and the positioning drive motor are both electrically connected to the control device.

[0011] Preferably, a telescopic arc brush plate is provided at the bottom of the positioning rack, and the telescopic arc brush plate includes a fixed arc plate and two telescopic arc plates, and the two telescopic arc plates are arranged in a slide groove in the fixed arc plate through an adjusting spring.

[0012] Preferably, the drilling device includes a drilling machine, the drilling machine is connected to a lifting hydraulic cylinder, the lifting hydraulic cylinder is connected to a cross slide, and the cross slide is arranged on the top of the inner side of the protective cover;

[0013] The drilling machine, the lifting hydraulic cylinder and the cross slide are all electrically connected to the control device.

[0014] Preferably, the pressurized connection device includes a connecting pressure plate, the connecting pressure plate is connected to the liquid pressurizing device through a hydraulic pipeline, a liquid pressure sensor is provided on the hydraulic pipeline, one end of the connecting pressure plate is connected to the telescopic end of the first docking hydraulic cylinder, the cylinder body of the first docking hydraulic cylinder is rotatably connected to the protective cover through a bearing, a rotating driven gear is provided on the cylinder body of the first docking hydraulic cylinder, the rotating driven gear is meshed with a rotating driving gear, the rotating driving gear is provided on the output shaft of the rotating drive motor, the rotating drive motor is installed on the protective cover, and a second docking hydraulic cylinder is also provided on the protective cover, and the telescopic end of the second docking hydraulic cylinder is arranged opposite to the other end of the connecting pressure plate in the docking position;

[0015] The first docking hydraulic cylinder, the second docking hydraulic cylinder, the liquid pressure sensor and the rotary drive motor are all electrically connected to the control device.

[0016] Preferably, a heating device is further provided, the heating device comprises a hot air blower, the air outlet pipe of the hot air blower is connected to the air inlet of the protective cover, the protective cover is provided with an air outlet, the air outlet is connected to a filter, and an infrared temperature sensor is provided inside the protective cover;

[0017] The hot air blower and the infrared temperature sensor are both electrically connected to the control device.

[0018] Preferably, a heating device is further provided, the heating device comprising a plurality of circumferentially distributed heating tubes, the heating tubes being mounted on the fixed arc plate and the two telescopic arc plates through angle adjustment seats, a penetrating arc hole being opened on the circumferential side of the fixed ring, and cleaning bristles being fixed on the upper and lower sides of the penetrating arc hole;

[0019] The protective cover is provided with an air outlet and an air inlet, both of which are connected with filters, the air outlet is connected with an exhaust fan, and an infrared temperature sensor is provided inside the protective cover;

[0020] The heating tube, the exhaust fan, the angle adjustment seat and the infrared temperature sensor are all electrically connected to the control device.

[0021] Based on the test method of the rock mass hydraulic fracturing test system, the specific steps are as follows:

[0022] Step S1: testing rock sample positioning;

[0023] The test rock sample is placed on the fixed base and located in the middle of the fixed ring. The positioning drive motor is started. The positioning drive motor drives the driving gear ring to rotate. The driving gear ring drives the synchronous gear and the driving gear to rotate, so that one end of the positioning rack moves toward the test rock sample. When the pressure values ​​of the three pressure sensors all reach the set values, the positioning drive motor stops, and the diameter of the test rock sample is calculated according to the rotation angle of the positioning drive motor.

[0024] Step S2: collecting preliminary images of test rock samples;

[0025] Start the imaging device to collect the image of the unprocessed test rock sample;

[0026] Step S3: drilling a test rock sample;

[0027] The drilling depth and the drilling diameter are calculated according to the diameter of the test rock sample, and the lifting hydraulic cylinder and the cross slide are started. The drilling machine drills according to the calculated drilling depth and the drilling diameter. After the drilling is completed, the drilling machine returns to the initial position, and intermittent image acquisition is performed while drilling. After the drilling is completed, the image acquisition is performed, and the fixed base is reciprocated and cleaned by the positioning mechanism. After the cleaning is completed, the positioning mechanism is in a state of clamping the test rock sample;

[0028] Step S4: preheating the environment and the test rock sample by a heating device according to actual needs;

[0029] Step S5: applying pressure test and performing image acquisition;

[0030] Start the rotary drive motor so that the connecting pressure plate is set opposite to the test rock sample, start the first docking hydraulic cylinder and the second docking hydraulic cylinder so that the connecting pressure plate covers the test rock sample, start the liquid pressurizing device, and collect the pressure value of the liquid pressure sensor in real time, record the pressure value curve, and determine the fracture pressure.

[0031] Therefore, the present invention adopts the above-mentioned rock mass hydraulic fracturing test system and test method, which has the following beneficial effects:

[0032] (1) A drilling device and a synchronous positioning mechanism were added to realize the positioning and drilling of rock samples and increase the function of the testing equipment.

[0033] (2) A rotating imaging device is provided, and the image acquisition time interval can be set according to the test needs during the test process, drilling process and other processes, so as to observe the changes of the test rock samples in real time and provide image data for subsequent analysis.

[0034] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the structure of a rock mass hydraulic fracturing test system of the present invention;

[0036] Figure 2 It is a schematic structural diagram of the rotary imaging device of the present invention;

[0037] Figure 3 This is a schematic diagram of the structure of the synchronous positioning mechanism of Example 1 of the present invention;

[0038] Figure 4 This is a schematic diagram of the structure of the telescopic arc brush plate of the present invention;

[0039] Figure 5 This is a schematic diagram of the structure of the synchronous positioning mechanism of Example 2 of the present invention;

[0040] Figure 6 This is a schematic diagram of the fixing ring structure of Example 2 of the present invention.

[0041] Reference numerals

[0042] 1. Control device; 2. Liquid pressurizing device; 3. Rotating imaging device; 31. Turntable; 32. Mounting frame; 33. Lifting screw rod; 34. X-ray generator; 35. Detector; 36. Lifting drive motor; 37. Timing belt; 4. Fixed base; 41. Water guide groove; 42. Drain groove; 5. Protective cover; 51. Air inlet; 52. Air outlet; 6. Drilling device; 61. Drilling machine; 62. Lifting hydraulic cylinder; 63. Cross slide; 7. Pressurizing connection device; 71. Connecting pressure plate; 72. First docking liquid Pressure cylinder; 73, rotating driven gear; 74, rotating driving gear; 75, rotating driving motor; 76, second docking hydraulic cylinder; 8, synchronous positioning mechanism; 81, fixing ring; 811, guide groove; 812, penetrating arc hole; 82, positioning rack; 83, pressure sensor; 84, driving gear; 85, driving gear ring; 86, positioning driving motor; 87, fixing arc plate; 871, slide groove; 88, telescopic arc plate; 9, hot air blower; 10, heating tube; 11, filter; 12, infrared temperature sensor. DETAILED DESCRIPTION

[0043] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0045] Example 1

[0046] like Figure 1 As shown, a rock hydraulic fracturing test system includes a control device 1, a liquid pressurizing device 2 (hydraulic source), a rotating imaging device 3, a fixed base 4 and a protective cover 5. The protective cover 5 is arranged on the fixed base 4. A drilling device 6 and a pressurizing connecting device 7 are arranged in the protective cover 5. A synchronous positioning mechanism 8 is arranged inside the fixed base 4. The rotating imaging device 3, the drilling device 6 and the pressurizing connecting device 7 are all electrically connected to the control device 1.

[0047] like Figure 2 As shown, the rotary imaging device 3 includes a turntable 31, and two mounting frames 32 arranged opposite to each other are arranged on the circumferential side of the turntable 31. The two mounting frames 32 are each provided with a lifting screw 33, one of the lifting screws 33 is provided with an X-ray generator 34, and the other lifting screw 33 is provided with a detector 35. The two lifting screws 33 are connected by a synchronous belt 37, and one of the lifting screws 33 is connected to a lifting drive motor 36 fixed on the mounting frame 32 to achieve synchronous lifting and rotation of the X-ray generator 34 and the detector 35. The turntable 31, the lifting drive motor 36, the X-ray generator 34 and the detector 35 are all electrically connected to the control device 1 to achieve the acquisition of the test rock sample image, so as to facilitate the test personnel to observe the images of the test rock sample at the initial stage, during processing, after processing, during pressurization and after pressurization, as well as the changes of the test rock sample between each step.

[0048] The fixed base 4 is mounted on the turntable 31 through a bearing, so that when the X-ray generator 34 and the detector 35 rotate, the fixed base 4 does not rotate. The fixed base 4 is provided with water guide grooves 41 distributed around the circumference, and a drainage groove 42 is provided in the middle of the fixed base. One end of the water guide groove 41 is connected to the drainage groove 42, and the drainage groove 42 is connected to a drainage pipe. Since water spraying is used to cool down during drilling, and dust on the surface of the test rock sample is cleaned at the same time, the dust is discharged from the drainage groove 42 and the drainage pipe through water flow.

[0049] like Figure 3 As shown, the synchronous positioning mechanism 8 includes a fixed ring 81, and four guide grooves 811 are distributed circumferentially on the upper end surface of the fixed ring 81. A positioning rack 82 is slidably arranged in the guide groove 811, and a pressure sensor 83 is arranged on the top of the positioning rack 82. The positioning rack 82 is meshed with a driving gear 84 on the fixed ring 81, and a synchronous gear is arranged on the rotating shaft of the driving gear 84. The synchronous gear is meshed with a driving gear ring 85 in the fixed ring 81, and the driving gear ring 85 is meshed with a gear on the output shaft of a positioning drive motor 86. The positioning drive motor 86 is installed on the fixed ring 81. The pressure sensor 83 and the positioning drive motor 86 are both electrically connected to the control device 1. The four positioning racks 82 move synchronously, so that the test rock sample moves to the center position under the action of the four positioning racks 82, which is convenient for subsequent processing and docking.

[0050] The drilling device 6 includes a drilling machine 61, the drilling machine 61 is connected to a lifting hydraulic cylinder 62, the lifting hydraulic cylinder 62 is connected to a cross slide 63, the cross slide 63 is arranged on the top of the inner side of the protective cover 5, the drilling machine 61, the lifting hydraulic cylinder 62 and the cross slide 63 are all electrically connected to the control device 1 to realize the three-dimensional movement of the drilling machine 61.

[0051] In order to improve the dust removal effect, a telescopic arc-shaped brush plate is provided at the bottom of the positioning rack 82, such as Figure 4 As shown, the telescopic arc brush plate includes a fixed arc plate 87 and two telescopic arc plates 88. Bristles are arranged at the bottom of the fixed arc plate 87 and the two telescopic arc plates 88. The two telescopic arc plates 88 are arranged in a slide groove 871 in the fixed arc plate 87 through an adjusting spring. During the movement of the positioning rack 82, the four telescopic arc brush plates always form a circle under the action of the adjusting spring, thereby cleaning the fixed base 4 in all directions.

[0052] The pressurized connection device 7 includes a connecting plate 71, which is connected to the liquid pressurizing device 2 through a hydraulic pipeline. A liquid pressure sensor 83 is provided on the hydraulic pipeline. One end of the connecting plate 71 is connected to the telescopic end of the first docking hydraulic cylinder 72. The cylinder body of the first docking hydraulic cylinder 72 is rotatably connected to the protective cover 5 through a bearing. A rotating driven gear 73 is provided on the cylinder body of the first docking hydraulic cylinder 72. The rotating driven gear 73 is meshed with a rotating driving gear 74. The rotating driving gear 74 is arranged on the output shaft of the rotating drive motor 75. The rotating drive motor 75 is installed on the protective cover 5. A second docking hydraulic cylinder 76 is also provided on the protective cover 5. The telescopic end of the second docking hydraulic cylinder 76 is arranged opposite to the other end of the connecting plate 71 in the docking position. The first docking hydraulic cylinder 72, the second docking hydraulic cylinder 76, the liquid pressure sensor 83 and the rotating drive motor 75 are all electrically connected to the control device 1, which are used to realize the docking of the connecting plate 71 with the test rock sample after drilling, and do not affect each other with the drilling device 6.

[0053] In order to reduce the influence of the temperature field, the test system is also provided with a heating device, which includes a hot air blower 9. The air outlet pipe of the hot air blower 9 is connected to the air inlet 51 of the protective cover 5. The protective cover 5 is provided with an air outlet 52. The air outlet 52 is connected to a filter 11. An infrared temperature sensor 12 is provided on the inside of the protective cover 5. The hot air blower 9 and the infrared temperature sensor 12 are both electrically connected to the control device 1, so as to realize the temperature regulation of the inside of the protective cover 5 and the test rock sample.

[0054] Based on the test method of the rock mass hydraulic fracturing test system, the specific steps are as follows:

[0055] Step S1: test rock sample positioning.

[0056] The test rock sample is placed on the fixed base 4 and located in the middle of the fixed ring 81, and the positioning drive motor 86 is started. The positioning drive motor 86 drives the driving gear ring 85 to rotate, and the driving gear ring 85 drives the synchronous gear and the driving gear 84 to rotate, so that one end of the positioning rack 82 moves toward the test rock sample. When the pressure values ​​of the three pressure sensors 83 all reach the set values, the positioning drive motor 86 stops, and the diameter of the test rock sample is calculated according to the rotation angle of the positioning drive motor 86.

[0057] Step S2: Collect preliminary images of the test rock sample.

[0058] The imaging device is started to collect images of the unprocessed test rock sample.

[0059] Step S3: drilling a test rock sample.

[0060] The drilling depth and the drilling diameter are calculated according to the diameter of the test rock sample, and the lifting hydraulic cylinder 62 and the cross slide 63 are started. The drilling machine 61 drills according to the calculated drilling depth and drilling diameter. After the drilling is completed, the drilling machine 61 returns to the initial position, and intermittent image acquisition is performed while drilling. After the drilling is completed, the image acquisition is performed, and the fixed base 4 is reciprocated and cleaned through the positioning mechanism. After the cleaning is completed, the positioning mechanism is in a state of clamping the test rock sample.

[0061] Step S4: preheating the environment and the test rock sample by a heating device according to actual needs, that is, starting the hot air blower 9 to continuously provide hot air into the protective cover 5 until the test rock sample reaches the test temperature.

[0062] Step S5: applying pressure test and performing image acquisition;

[0063] Start the rotary drive motor 75 so that the connecting pressure plate 71 is arranged opposite to the test rock sample, start the first docking hydraulic cylinder 72 and the second docking hydraulic cylinder 76 so that the connecting pressure plate 71 covers the test rock sample, start the liquid pressurizing device 2, and collect the pressure value of the liquid pressure sensor 83 in real time, record the pressure value curve, and determine the fracture pressure.

[0064] Example 2

[0065] The difference between this embodiment and embodiment 1 is that the heating device is different, such as Figure 5 - Figure 6 As shown, since the temperature of the test rock sample is not easy to reach the internal uniformity, the heating time is long by hot air heating. The heating device of this embodiment includes a plurality of circumferentially distributed heating tubes 10, which are installed on the fixed arc plate 87 and two telescopic arc plates 88 through an angle adjustment seat (driven by a motor), and a through arc hole 812 is opened on the circumferential side of the fixed ring 81, and cleaning bristles (not shown in the figure) are fixed on the upper and lower sides of the through arc hole 812. The through arc hole 812 is used to avoid the heating tube 10, and the dust and debris on the surface of the heating tube 10 can also be cleaned when the heating tube 10 passes. The protective cover 5 is provided with an air outlet 52 and an air inlet 51, and the air outlet 52 and the air inlet 51 are both connected to a filter 11, and the air outlet 52 is connected to an exhaust fan, and an infrared temperature sensor 12 is arranged inside the protective cover 5. The heating tube 10, the exhaust fan, the angle adjustment seat and the infrared temperature sensor 12 are all electrically connected to the control device 1.

[0066] During the positioning process, test rock sample drilling, preliminary image acquisition process and test process, the heating tube 10 is in a horizontal state to avoid blocking the rotating imaging device 3. During the preheating stage, the heating tube 10 is turned to a vertical state through the angle adjustment seat, so that the heating tube 10 is closer to the test rock sample, thereby improving the preheating effect.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A rock mass hydraulic fracturing test system, comprising a control device and a liquid pressurizing device, characterized in that: The invention also includes a rotating imaging device, a fixed base and a protective cover, wherein the protective cover is arranged on the fixed base, the fixed base is arranged in the middle of the rotating imaging device through a bearing, a drilling device and a pressurizing connecting device are arranged in the protective cover, a synchronous positioning mechanism is arranged inside the fixed base, and the rotating imaging device, the drilling device and the pressurizing connecting device are all electrically connected to the control device; The synchronous positioning mechanism comprises a fixed ring, at least three guide grooves are distributed on the circumference of the upper end surface of the fixed ring, a positioning rack is slidably arranged in the guide groove, a pressure sensor is arranged on the top of the positioning rack, the positioning rack is meshed with the driving gear on the fixed ring, a synchronous gear is arranged on the rotating shaft of the driving gear, the synchronous gear is meshed with the driving gear ring in the fixed ring, the driving gear ring is meshed with the gear on the output shaft of the positioning drive motor, and the positioning drive motor is installed on the fixed ring; The pressure sensor and the positioning drive motor are both electrically connected to the control device; A telescopic arc-shaped brush plate is arranged at the bottom of the positioning rack, and the telescopic arc-shaped brush plate includes a fixed arc-shaped plate and two telescopic arc-shaped plates, and the two telescopic arc-shaped plates are arranged in a slide groove in the fixed arc-shaped plate through an adjusting spring; A heating device is also provided, which includes a plurality of circumferentially distributed heating tubes, which are mounted on the fixed arc plate and the two telescopic arc plates through angle adjustment seats, and a through arc hole is opened on the circumferential side of the fixed ring, and cleaning bristles are fixed on the upper and lower sides of the through arc hole; The protective cover is provided with an air outlet and an air inlet, both of which are connected with filters, the air outlet is connected with an exhaust fan, and an infrared temperature sensor is provided inside the protective cover; The heating tube, the exhaust fan, the angle adjustment seat and the infrared temperature sensor are all electrically connected to the control device; The pressurized connection device includes a connecting pressure plate, the connecting pressure plate is connected to the liquid pressurizing device through a hydraulic pipeline, a liquid pressure sensor is arranged on the hydraulic pipeline, one end of the connecting pressure plate is connected to the telescopic end of the first docking hydraulic cylinder, the cylinder body of the first docking hydraulic cylinder is rotatably connected to the protective cover through a bearing, a rotating driven gear is arranged on the cylinder body of the first docking hydraulic cylinder, the rotating driven gear is meshed with a rotating driving gear, the rotating driving gear is arranged on the output shaft of the rotating drive motor, the rotating drive motor is installed on the protective cover, and a second docking hydraulic cylinder is also arranged on the protective cover, and the telescopic end of the second docking hydraulic cylinder is arranged opposite to the other end of the connecting pressure plate in the docking position; The first docking hydraulic cylinder, the second docking hydraulic cylinder, the liquid pressure sensor and the rotary drive motor are all electrically connected to the control device.

2. The rock mass hydraulic fracturing test system according to claim 1, characterized in that: The rotary imaging device comprises a turntable, and two mounting frames arranged opposite to each other are arranged on the circumferential side of the turntable, and lifting screws are arranged on both mounting frames, one of the lifting screws is arranged on an X-ray generator, and the other lifting screw is arranged on a detector, and the two lifting screws are connected by a synchronous belt, and one of the lifting screws is connected to a lifting drive motor fixed on the mounting frame; The turntable, the lifting drive motor, the X-ray generator and the detector are all electrically connected to the control device.

3. The rock mass hydraulic fracturing test system according to claim 1, characterized in that: The fixed base is installed on the turntable through a bearing. A water guide groove is distributed on the circumference of the fixed base. A drainage groove is arranged in the middle of the fixed seat. One end of the water guide groove is communicated with the drainage groove, and the drainage groove is connected with a drainage pipe.

4. The rock mass hydraulic fracturing test system according to claim 1, characterized in that: The drilling device includes a drilling machine, the drilling machine is connected to a lifting hydraulic cylinder, the lifting hydraulic cylinder is connected to a cross slide, and the cross slide is arranged on the top of the inner side of the protective cover; The drilling machine, the lifting hydraulic cylinder and the cross slide are all electrically connected to the control device.

5. The testing method of the rock mass hydraulic fracturing test system according to claim 4 is characterized in that: The specific steps are as follows: Step S1: testing rock sample positioning; The test rock sample is placed on the fixed base and located in the middle of the fixed ring. The positioning drive motor is started. The positioning drive motor drives the driving gear ring to rotate. The driving gear ring drives the synchronous gear and the driving gear to rotate, so that one end of the positioning rack moves toward the test rock sample. When the pressure values ​​of the three pressure sensors all reach the set values, the positioning drive motor stops, and the diameter of the test rock sample is calculated according to the rotation angle of the positioning drive motor. Step S2: collecting preliminary images of test rock samples; Start the imaging device to collect the image of the unprocessed test rock sample; Step S3: drilling a test rock sample; The drilling depth and the drilling diameter are calculated according to the diameter of the test rock sample, and the lifting hydraulic cylinder and the cross slide are started. The drilling machine drills according to the calculated drilling depth and the drilling diameter. After the drilling is completed, the drilling machine returns to the initial position, and intermittent image acquisition is performed while drilling. After the drilling is completed, the image acquisition is performed, and the fixed base is reciprocated and cleaned by the positioning mechanism. After the cleaning is completed, the positioning mechanism is in a state of clamping the test rock sample; Step S4: preheating the environment and the test rock sample by a heating device according to actual needs; Step S5: applying pressure test and performing image acquisition; Start the rotary drive motor so that the connecting pressure plate is set opposite to the test rock sample, start the first docking hydraulic cylinder and the second docking hydraulic cylinder so that the connecting pressure plate covers the test rock sample, start the liquid pressurizing device, and collect the pressure value of the liquid pressure sensor in real time, record the pressure value curve, and determine the fracture pressure.

Images