Geostress testing device and testing method

Abstract

The application discloses a ground stress testing device and testing method, which comprises a pressurized water injection device, a drill pipe, an upper packer, a rotatable flow guide plate, an electronic compass and a lower packer. One end of the drill pipe is communicated with the pressurized water injection device, and the other end is communicated with a water inlet of a channel switching valve. The channel switching valve further comprises a first water outlet channel and a second water outlet channel which are selectively communicated with the water inlet. The upper packer is communicated with the first water outlet channel. The rotatable flow guide plate comprises a central flow guide pipe which is rotatably arranged between the upper packer and the lower packer, and flow guide blades which are arranged on the central flow guide pipe. A flow guide slit is arranged on the flow guide blades. When water flows into the central flow guide pipe and is sprayed through the flow guide slit, the flow guide blades rotate and drive the electronic compass to rotate, so that the automatic tracking of the water pressure crack direction is realized. The lower packer is connected with the upper packer through a rigid pipeline. The application has simple structure, low manufacturing cost, and can measure the stress size and direction of rock mass simultaneously.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of rock mass mechanics test, and particularly relates to a geostress testing device and a testing method. BACKGROUND

[0002] The conventional water pressure fracturing method geostress test mainly includes two parts: hydraulic fracturing test and fracturing crack impression test, and the stress value and stress direction of the test rock mass can be obtained according to the water pressure fracturing method mechanics theory. At present, the conventional water pressure fracturing method geostress test method mainly realizes the stress size and direction by independent test, and the long time consumption, complicated operation and repeated test can easily lead to the drilling instability, and more manpower and material resources need to be invested. With the development of technology, some water pressure fracturing geostress testing devices which can simultaneously collect the stress size and direction also appear, and according to the main characteristics, the devices can be divided into two categories: one is to characterize the direction of the fracturing crack based on the wave velocity imaging method in the process of forming the fracturing crack; and the other is to directly show the direction of the fracturing crack by combining the drilling television imaging method in the process of forming the crack. The two methods can simultaneously collect the stress size and direction of the test rock mass, but the manufacturing cost is very high, and the degree of popularization is low. Therefore, it is necessary to develop a geostress testing device and method which has lower manufacturing cost and is simpler and more convenient to implement. SUMMARY

[0003] One object of the present application is to provide a geostress testing device which has simple structure, low manufacturing cost and can simultaneously collect the maximum horizontal principal stress size and direction of the rock mass.

[0004] To solve the above technical problems, the application adopts the following technical scheme:

[0005] A geostress testing device, comprising a pressurized water injection device, a drill pipe, a channel switching valve, an upper packer, a rotatable flow guide plate, an electronic compass and a lower packer; wherein,

[0006] The pressurized water injection device is used for pressurized water injection in the test process, and the pressurized device is further connected with a data acquisition device, and the data acquisition device is used for collecting stress data;

[0007] The drill pipe is in communication with the pressurized water injection device at one end and in communication with the water inlet of the channel switching valve at the other end, and the channel switching valve further comprises a first water outlet channel and a second water outlet channel which are in selective communication with the water inlet, the water inlet is in communication with the first water outlet channel by pulling up the drill pipe relative to the upper packer, and the water inlet is in communication with the second water outlet channel by pressing down the drill pipe relative to the upper packer;

[0008] The upper packer is in communication with the first water outlet channel;

[0009] The rotatable flow guide plate comprises a central flow guide pipe and flow guide vanes arranged on the central flow guide pipe, one end of the central flow guide pipe is rotatably arranged in the upper packer central rod, the other end is connected with the center of the electronic compass shell, the central flow guide pipe is provided with a shaft hole communicated with the second water outlet passage, the flow guide vanes are provided with flow guide slits communicated with the shaft hole, the flow guide vanes are rotated under the action of water flow in the process of water flow from the second water outlet passage into the shaft hole and being sprayed through the flow guide slits, and the electronic compass shell is rotated relative to the electronic compass pointer, the electronic compass is arranged on the lower packer central axis through the base.

[0010] The lower packer is connected with the upper packer through a rigid pipeline.

[0011] Further, the pressurized water injection device comprises a high-pressure water pump, a high-pressure water pipe connected with the high-pressure water pump at one end, and a pressure gauge arranged on the high-pressure water pipe, the other end of the high-pressure water pipe is connected with the drill pipe through a pipe joint, wherein the data acquisition device is connected to the high-pressure water pipe through the pressure sensor for collecting stress information of the test section.

[0012] Further, the testing device further comprises a winch device connected with the pipe joint for lifting or lowering the drill pipe.

[0013] Further, the upper packer has a central pipeline communicated with the second water outlet passage and an inner cavity communicated with the first water outlet passage, the central pipeline and the inner cavity are not communicated with each other.

[0014] Further, the flow guide vanes comprise at least two inner flow guide vanes symmetrically arranged on the central flow guide pipe, and outer flow guide vanes arranged on the central flow guide pipe and located on both sides of each inner flow guide vane, wherein the flow guide slits are formed between each outer flow guide vane and the corresponding inner flow guide vane, and the through holes communicated with the flow guide slits are arranged on the pipe wall of the central flow guide pipe.

[0015] Further, the width of the inner flow guide vane in the radial direction is greater than the width of the outer flow guide vane in the radial direction.

[0016] Further, the rotatable flow guide plate further comprises a limiting flow stabilizing pipe, one end of the central flow guide pipe is connected with the central pipeline, the limiting flow stabilizing pipe is inserted into the one end of the central flow guide pipe connected with the central pipeline, the limiting flow stabilizing pipe has a limiting ring on the outer pipe wall of the one end close to the second water outlet passage, the limiting ring is used to limit the water flowing out of the central pipeline from directly flowing into the central flow guide pipe, and the outer diameter of the limiting ring is equivalent to the inner diameter of the central pipeline.

[0017] Further, a pointing line is marked on the outer shell of the electronic compass, and in the initial state, the pointing line is parallel to the extending direction of the guide vane in the radial direction of the borehole; and the electronic compass can record the included angle between the pointing line and the north direction in real time during the test.

[0018] Further, the base comprises a support seat arranged on the central axis of the lower packer, a support column arranged on the support seat, a connecting bearing sleeved on the support column, and a connecting column connected with the connecting bearing and used for supporting the electronic compass.

[0019] Another object of the present application is to provide a test method of the water pressure fracturing in-situ stress testing device.

[0020] Step 1, place the drill pipe in the borehole and ensure that the upper and lower packers are lowered to the specified depth, pull the drill pipe relative to the upper packer, connect the water inlet of the channel conversion valve with the first water outlet passage, open the water injection and pressurization device and gradually pressurize to the predetermined pressure, the high-speed water flow enters the upper packer through the drill pipe and the first water outlet passage of the channel conversion valve and enters the lower packer through the rigid pipeline, under the action of water and pressure, the upper and lower packers expand and tightly adhere to the borehole wall, and the sealed space formed between the upper and lower packers is the test section;

[0021] Step 2, press down the drill pipe to connect the water inlet of the channel conversion valve with the second water outlet passage, continuously pressurize and inject water by the water injection and pressurization device, and collect the water pressure fracturing stress parameters in the working process by using the data acquisition device;

[0022] Step 3, keep the water injection and pressurization device working continuously, continuously inject high-speed water flow into the drill pipe, then flow into the shaft hole of the central guide pipe through the second water outlet passage of the channel conversion valve, and then sprayed through the guide slot, while in the test section clamped by the upper and lower packers, the continuous water flow can only be injected into the rock mass cracks through the fracturing cracks formed by the borehole wall, the guide vane gradually rotates to the direction of the fracturing cracks under the continuous action of the fluid force and keeps stable, the electronic compass shell rotates relative to the electronic compass pointer in the process of rotation of the guide vane, and the orientation of the rock mass in-situ stress in this section can be obtained according to the change of the included angle between the two, and the orientation is determined as the direction of the maximum horizontal principal stress of the rock mass in this section;

[0023] Step 4, after the data acquisition is completed, stop the pressurized water injection device, pull the drill pipe, connect the water inlet of the channel conversion valve with the first water outlet passage, at this time, the pressure water in the upper and lower packers flows out along the channel conversion valve, the drill pipe and the pressurized water injection device, the upper and lower packers shrink and separate from the hole wall, and return to the initial state, that is, the test of the water pressure fracturing in-situ stress value and direction in this section is completed, and the above process can be repeated to realize the test of the stress value and direction of the next section.

[0024] Compared with the prior art, the application has the beneficial effects that:

[0025] The test device of the application is designed based on the fluid mechanics characteristics of the fracture formation process, and in each test, not only the stress size of the rock mass can be collected through the data collection device, but also the stress direction can be obtained through the cooperation of the rotatable flow guide plate and the electronic compass, the entire ground stress test can be completed only once by drilling, and the test time, manpower and material resources are greatly saved, the risk of repeated drilling is reduced, obvious economic benefits are generated, the drilling test efficiency is improved, the test cost is reduced, the operation of the method is simple, the equipment requirement is low, and the method is convenient for large-scale popularization and application. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a structural schematic view of the hydraulic fracturing method ground stress test device of the embodiment of the application;

[0027] Figure 2 is a structural schematic view of the key device between the upper and lower packers of the embodiment of the application;

[0028] Figure 3 is a longitudinal section structural schematic view of the key device between the upper and lower packers of the embodiment of the application;

[0029] Figure 4 is Figure 3 is an enlarged structural schematic view of a in FIG. 6;

[0030] Figure 5 is Figure 3 is an enlarged structural schematic view of b in FIG. 6;

[0031] Figure 6 is Figure 3 is a section view of I-I in FIG. 6;

[0032] Figure 7 is Figure 3 is a section view of II-II in FIG. 6;

[0033] Figure 8 is a whole-process stress value collection curve schematic view of the embodiment of the application;

[0034] Figure 9 is a flow field acting on the rotatable flow guide plate in the stress direction collection process of the embodiment of the application. DETAILED DESCRIPTION

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0036] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are conventional methods, and the reagents and materials mentioned are commercially available unless otherwise specified. In the description of this invention, the terms "lateral," "longitudinal," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Where there is no conflict, the embodiments and features in the embodiments of this invention can be combined with each other.

[0037] The present invention will be further described below with reference to specific embodiments, but these are not intended to limit the scope of the invention.

[0038] like Figures 1-7 As shown in the figure, this invention discloses a hydraulic fracturing stress testing device, including a pressurized water injection device, a drill rod 9, a channel switching valve 10, an upper packer 12, a rotatable guide plate 14, an electronic compass 15, and a lower packer 16. The pressurized water injection device includes a high-pressure water pump 1, a high-pressure water pipe 3 connected to the high-pressure water pump, a pressure gauge 4 and a pressure relief ball valve 5 installed on the high-pressure water pipe 3. To facilitate data acquisition during the test, a data acquisition device 2 for real-time data acquisition is also installed on the high-pressure water pipe 3. One end of the drill rod 9 is connected to the high-pressure water pipe 3 via a pipe joint 6. To facilitate lifting or lowering the drill rod 9 during the test, the pipe joint 6 is also connected to a winch device. The winch device includes a motor 8, a lifting rope wound on the motor shaft, a fixed pulley for the lifting rope to pass through, and a lifting basket 7. The lifting basket 7 is connected to the pipe joint 6. During the test, the winch device operates, lifting the pipe joint 6 through the lifting basket 7 to lift the drill rod 9. The drill rod 9 is a hollow rod. The other end of the drill rod 9 is connected to the inlet of the channel switching valve 10. The channel switching valve 10 also includes a first outlet passage and a second outlet passage selectively connected to the inlet. When the drill rod 9 is pulled up relative to the upper packer 12, the inlet is connected to the first outlet passage; when the drill rod 9 is pressed down relative to the upper packer 12, the inlet is connected to the second outlet passage.

[0039] like Figure 2As shown, the upper packer 12 is provided with a central pipe 12-1 communicating with the second water outlet passage and an inner cavity 12-2 communicating with the first water outlet passage, wherein the central pipe 12-1 and the inner cavity 12-2 are not communicated with each other, and the central pipe 12-1 is communicated with the second water outlet passage through the oil pipe 11. In addition, the upper packer 12 is further provided with a communication hole 12-3 communicating with the inner cavity 12-2. The lower packer 16 has the same structure as the upper packer 12. In the embodiment, the upper packer 12 and the lower packer 16 are communicated through three rigid pipes 13 arranged at equal intervals. In the embodiment, three rigid pipes 13 are arranged to prevent the extreme rigid pipe arrangement direction from being the same as the crack direction, thereby affecting the rotation of the electronic compass housing 15-1. Specifically, one end of the rigid pipe 13 is connected with the communication hole 12-3 of the upper packer 12, and the other end of the rigid pipe 13 is connected with the communication hole 16-3 of the lower packer 16. When the water flow enters the inner cavity 12-2 of the upper packer 12 from the first water outlet passage, it flows to the inner cavity 16-2 of the lower packer 16 through the communication hole 12-3 and the rigid pipe 13 in turn. The area between the upper and lower packers forms a test section during the test.

[0040] See Figure 3 , Figure 4 and Figure 6 The rotatable flow guide plate 14 includes a central flow guide pipe 14-1 and flow guide vanes arranged on the central flow guide pipe 14-1. The central flow guide pipe 14-1 is a hollow pipe having an axial hole 14-7 communicated with the central pipe 12-1 of the upper packer 12. The upper end of the central flow guide pipe 14-1 is arranged in the lower end of the central pipe 12-1 of the upper packer 12, and the central flow guide pipe 14-1 is connected with the lower end of the upper packer through a bearing, while the lower end of the central flow guide pipe 14-1 is connected with the center of the electronic compass housing 15-1, so that the central flow guide pipe 14-1 can rotate freely, and the rotation of the central flow guide pipe 14-1 will drive the electronic compass housing 15-1 to rotate relative to the electronic compass pointer. In order to reduce the influence of water flow disturbance, a limiting flow stabilizing pipe 14-2 is arranged at the upper end of the central flow guide pipe 14-1, and a limiting ring 14-3 is arranged on the outer wall of the upper end of the limiting flow stabilizing pipe 14-2. The outer diameter of the limiting ring 14-3 is equivalent to the inner diameter of the central pipe 12-2, so that the upper end of the central flow guide pipe 14-1 is limited between the limiting flow stabilizing pipe 14-2 and the central pipe 12-2. In this way, when the water flow enters the central pipe 12-2, it is completely guided to the central flow guide pipe 14-1 through the limiting flow stabilizing pipe 14-2, thereby avoiding the influence of water flow disturbance on the central flow guide pipe 14-1.

[0041] The guide vane comprises inner guide vanes 14-4 arranged on the central guide pipe 14-1, outer guide vanes 14-5 arranged on the central guide pipe 14-1 and located on both sides of each inner guide vane 14-4, in the embodiment, two inner guide vanes 14-4 are symmetrically arranged on the central guide pipe 14-1, a guide slit 14-6 is formed between each outer guide vane 14-5 and the corresponding inner guide vane 14-4, and a through hole is arranged on the pipe wall of the central guide pipe 14-1 to communicate the shaft hole 14-7 with the guide slit 14-6. When the water flow enters the shaft hole 14-7 of the central guide pipe 14-1, the water flow is sprayed from the guide slit 14-6, according to Bernoulli's principle, the fluid always flows from a high potential area to a low potential area, and in order to achieve an optimal (shortest) flow path, the guide vane is gradually rotated to point to the direction of the fracturing crack at the minimum angle under the continuous action of the fluid and remains stable, and the guide vane drives the electronic compass shell 15-1 to rotate through the central guide pipe 14-1 in the process of rotation. In order to better obtain the stress direction, a pointing line is marked on the electronic compass shell in advance, the pointing line is the same as the extension direction of the inner guide vane 14-4 in the radial direction of the drill hole in the initial state, so that the pointing line also rotates in the process of rotation of the electronic compass shell 15-1 relative to the electronic compass pointer, and finally the angle change between the pointing line and the north direction can obtain the direction of the fracturing crack. In order to make the rotation of the guide vane more sensitive, the width of the inner guide vane 14-4 in the radial direction of the drill hole is greater than the width of the outer guide vane 14-5 in the radial direction of the drill hole, and the width of the inner guide vane 14-4 is greater than half of the radius of the drill hole 17. In this way, under the action of the water flow, the rotation sensitivity of the inner guide vane 14-4 is higher, so that the rotation sensitivity of the compass pointer 15-5 is also higher.

[0042] As shown in Figure 5 The electronic compass 15 is arranged on the lower packer 16 through the base, and specifically, the base comprises a support seat 15-4 arranged on the lower packer, a support column 15-3 arranged on the support seat 15-4, a connecting bearing sleeved on the support column 15-3, and a connecting column 15-2 connected with the connecting bearing and used for supporting the electronic compass 15, and the arrangement structure guarantees the rotation sensitivity of the central guide pipe 14-1 and the electronic compass 15.

[0043] The embodiment of the present application also provides a testing method of the water pressure fracturing ground stress testing device, which comprises the following steps:

[0044] Step 1, start the motor 8 of the hoisting device, place the drill pipe 9 in the borehole by the hoisting basket 7 of the hoisting device, and ensure that the upper and lower packers are lowered to a specified depth, place the high-pressure water pump 1 at a suitable position on the ground, and connect the data acquisition device 2, then sequentially connect the high-pressure water pump 1, the high-pressure water pipe 3, the pipe joint 6, and the drill pipe 9; relative to the upper packer 12, pull the drill pipe 9, connect the water inlet of the channel conversion valve 10 with the first water outlet path, turn on the high-pressure water pump 1 and gradually pressurize to a predetermined pressure, the high-pressure water flow enters the inner cavity 12-2 of the upper packer 12 through the high-pressure water pipe 3, the drill pipe 9, and the first water outlet path of the channel conversion valve 10, and then enters the inner cavity 16-2 of the lower packer 16 through the communication hole 12-3 in communication with the inner cavity 12-2 and the rigid pipe 13, under the action of water and pressure, the upper and lower packers expand and tightly adhere to the borehole wall, and the area between the upper and lower packers is the test section;

[0045] Step 2, operate the hoisting device to gently lower the drill pipe 9, which is blocked by the frictional resistance generated by the upper and lower packers on the hole wall, causing the drill pipe 9 to naturally stop descending, at this time the water inlet of the channel conversion valve 10 is connected with the second water outlet path, in this state, the test section is pressurized and watered by the high-pressure water pump 1 and the stress information is collected by the data acquisition device 2, the collection process curve is as shown in Figure 5 It should be noted that the previous several cycle curves are mainly to collect water pressure fracturing stress parameters (Pb, Pr and Ps), and the last cycle curve is to collect the specific orientation of the fracturing fracture;

[0046] Step 3, keep the high-pressure water pump 1 working continuously, the high-pressure water pump 1 injects high-pressure water flow into the drill pipe 9 through the high-pressure water pipe 3, and then flows into the shaft hole 14-7 of the central flow guide pipe 14-1 through the second water outlet path of the channel conversion valve 10, and then is sprayed out through the flow guide slot 14-6, while in the test section clamped by the upper and lower packers, the continuous water flow can only be injected into the rock gap through the fracturing fracture formed by the borehole 17 wall, given that the initial direction of the flow guide vane is not clear, it is assumed as shown in Figure 8 At this time, analyzing the flow field of the water flow in the test section and the mechanical relationship of the inner flow guide vane 14-4, it can be known that the flow guide vane is obviously in an unbalanced force state, according to Bernoulli's principle, fluid always flows from high potential area to low potential area, in order to achieve an optimal (shortest) flow path, the flow guide vane gradually rotates to the direction of the fracturing fracture along the smallest angle under the continuous action of the fluid and remains stable, as shown in Figure 9As shown, the guide vane drives the electronic compass shell 15-1 and the pointing line thereon to rotate and point to the fracturing fracture in the process of rotation, the time period corresponding to the last cycle curve is recorded, and the stable indicating direction of the pointing line on the electronic compass shell 15-1 is the water pressure fracturing fracture direction of the rock mass of the test section, and the specific direction of the water pressure fracturing fracture of the rock mass of the test section can be determined according to the change of the included angle between the stable indicating direction of the pointing line and the electronic compass pointer (i.e. the north direction);

[0047] Step 4, after the data acquisition is completed, the high-pressure water pump 1 is closed and separated from the high-pressure water pipe 3, the hoisting device is operated, the drill pipe 9 is lifted by the lifting basket 7, the water inlet of the channel conversion valve 10 is connected with the first water outlet passage, at this time, the pressure water in the inner cavity of the upper and lower packers will flow out along the channel conversion valve 10, the drill pipe 9, the pipe joint 6, the high-pressure water pipe 3 and the pressure relief ball valve 5, so as to achieve the purpose of pressure relief, the upper and lower packers are contracted and separated from the hole wall, that is, the test of the water pressure fracturing in-situ stress value and direction of the section is completed;

[0048] Step 5, the hoisting device is operated to increase or decrease the drill pipe to reach the next measurement position, and the above process is repeated to realize the rapid and continuous test of the next measurement section.

[0049] Step 6, after the test of all selected sections is completed, the in-hole test device is taken out, the orientation storage information of the compass pointer of the electronic compass in each measurement section is read, and finally the stable indicating direction of the electronic compass pointer in the continuous water injection time of each measurement section is determined as the maximum horizontal principal stress direction (i.e. the water pressure fracturing fracture direction) of the rock mass of the measurement section.

[0050] The above is only the preferred embodiment of the present application, and does not limit the implementation and protection scope of the present application. For those skilled in the art, it should be realized that any equivalent replacement and obvious change made according to the content of the present application should be included in the protection scope of the present application.

Claims

1. A geostress testing apparatus, characterized by, The test device comprises a pressurized water injection device, a drill pipe, a channel switching valve, an upper packer, a rotatable flow guide plate, an electronic compass and a lower packer. The pressurized water injection device is used for pressurized water injection during the test, and is connected with a data acquisition device. The drill pipe is connected with the pressurized water injection device at one end and is connected with a water inlet of the channel switching valve at the other end. The upper packer is connected with the first water outlet channel. The rotatable flow guide plate comprises a central flow guide pipe and flow guide blades arranged on the central flow guide pipe. The lower packer is connected with the upper packer through a rigid pipeline.

2. The in-situ ground stress testing device of claim 1, wherein, The pressurized water injection device comprises a high-pressure water pump, a high-pressure water pipe connected with the high-pressure water pump at one end, and a pressure gauge arranged on the high-pressure water pipe.

3. The in-situ ground stress testing device of claim 2, wherein, The test device further comprises a hoisting device connected with the pipeline joint and used for lifting or lowering the drill pipe.

4. The in-situ ground stress testing device of claim 1, wherein, The upper packer has a central pipeline connected with the second water outlet channel and an inner cavity connected with the first water outlet channel.

5. The in-situ ground stress testing device of claim 1, wherein, The flow guide blades comprise inner flow guide blades arranged on the central flow guide pipe and outer flow guide blades arranged on the central flow guide pipe and located on both sides of each inner flow guide blade.

6. The in-situ ground stress testing device of claim 5, wherein, The width of the inner flow guide blades in the radial direction is greater than the width of the outer flow guide blades in the radial direction.

7. The in-situ ground stress testing device of claim 4, wherein, The rotatable flow guide plate further comprises a limiting flow stabilizing pipe.

8. The in-situ ground stress testing device of claim 1, wherein, An indicating line is marked on the electronic compass housing. In the initial state, the indicating line is the same as the extending direction of a flow guide blade in the radial direction.

9. The in-situ stress testing device of claim 1, wherein, The base comprises a support seat arranged on the central axis of the lower packer, a support column arranged on the support seat, a connecting bearing sleeved on the support column, and a connecting column connected with the connecting bearing and fixed with the electronic compass.

10. A testing method of the geostress testing device according to any one of claims 1-9, characterized in that, The method comprises the following steps: Step 1, place the drill pipe in the borehole and ensure that the upper and lower packers are lowered to the specified depth, pull the drill pipe, connect the water inlet of the channel conversion valve with the first water outlet path, open the water injection and pressurization device and gradually pressurize to the predetermined pressure, the high-pressure water flow enters the upper packer through the drill pipe, the first water outlet path of the channel conversion valve and enters the lower packer through the rigid pipeline, under the action of water and pressure, the upper and lower packers expand and tightly adhere to the borehole wall, and the sealed space formed between the upper and lower packers is the test section; Step 2, press down the drill pipe to connect the water inlet of the channel conversion valve with the second water outlet path, the water injection and pressurization device continues to pressurize and inject water, and the data acquisition device is used to collect the water pressure fracturing stress parameters in the working process; Step 3, keep the water injection and pressurization device working continuously, the water injection and pressurization device continuously injects high-pressure water flow into the drill pipe, and then flows into the shaft hole of the central flow guide pipe through the second water outlet path of the channel conversion valve, and then is sprayed through the flow guide slot, while in the test section clamped by the upper and lower packers, the continuous water flow can only be injected into the rock mass through the fracturing cracks formed by the borehole wall, the flow guide vane is gradually rotated to the direction of the fracturing cracks under the continuous action of the fluid force and kept stable, the electronic compass shell is rotated relative to the electronic compass pointer in the process of rotation of the flow guide vane, the orientation of the rock mass ground stress of the section can be obtained according to the angle change between the two, and the orientation is determined as the direction of the maximum horizontal principal stress of the rock mass of the section; Step 4, after the data acquisition is completed, stop the work of the pressurized water injection device, pull the drill pipe, connect the water inlet of the channel conversion valve with the first water outlet path, at this time, the pressure water in the upper and lower packers flows out along the channel conversion valve, drill pipe and pressurized water injection device, the upper and lower packers shrink and separate from the hole wall, and return to the initial state, that is, the test of the water pressure fracturing ground stress value and direction of the section is completed, and the above process is repeated to realize the test of the stress value and direction of the next section.

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