A hydraulic fracturing in-situ stress measurement device

Abstract

The present invention belongs to the technical field of hydraulic fracturing, and discloses a hydraulic fracturing in-situ stress measurement device, which includes a water inlet module, a control valve, a packer module and a water passing valve connected in sequence; the water inlet module is connected to the top of the control valve; a fluid switching assembly is arranged in the control valve for switching fluid channels; a first channel and a second channel are arranged at the bottom of the control valve; the first channel penetrates through the test section of the packer module and is connected to the water passing valve for discharging gushing water or injecting water into the test section; the second channel injects water into two groups of expandable packers of the packer module to make them expand to form a test section; the test section is used to withstand high-pressure water to generate rock fractures for calculating in-situ stress parameters; a closable cover plate is arranged at the bottom of the water passing valve and is connected to the first channel and the second channel, and the cover plate is opened under the gushing water condition or closed under the water injection condition. The present invention can realize the free lowering of the measurement device in a gushing water borehole and ensure the controllability of the control valve under the action of high-pressure water.

Description

Technical Field

[0001] The present invention discloses a hydraulic fracturing in-situ stress measurement device, belonging to the technical field of hydraulic fracturing. Background Art

[0002] As a deep in-situ stress measurement method recommended by the International Society for Rock Mechanics in 1987, the hydraulic fracturing method has become the core means of deep-hole in-situ stress measurement by inducing rock mass fracture through high-pressure water injection and analyzing pressure response parameters (such as fracture pressure and reopening pressure). Its standard equipment includes a ground pipeline control system, a high-pressure water pump, an in-hole push-pull valve, upper and lower packers, and a fracturing screen pipe. The test process follows the standardized operation of "packer inflation - test section pressurization - data acquisition - equipment recovery".

[0003] However, under special hydrogeological conditions, especially when the borehole is located in an exploration adit, a low-elevation river valley area, or there is a confined aquifer, the water gushing phenomenon caused by the groundwater level in the hole being higher than the hole mouth will lead to the following problems: 1. The failure of the packer to be lowered: The upward thrust generated by the water gushing exceeds the self-weight of the equipment, resulting in the packer being unable to reach the predetermined depth; 2. The out-of-control state of the push-pull valve: The continuous water gushing pressure forces the push-pull valve to be in a non-designed state (compressed state), blocking the water injection channel required for the packer to expand and interrupting the test process.

[0004] In view of the above technical problems, there is an urgent need for a measurement device that can be freely lowered in a water-gushing borehole and ensure the controllability of the control valve under the action of high-pressure water. Summary of the Invention

[0005] The purpose of the present invention is to provide a hydraulic fracturing in-situ stress measurement device to solve the technical problems in the prior art that when there is water gushing in the borehole, the measurement device cannot be lowered by its own weight, and at the same time, the continuous pressure of the water gushing will cause the push-pull valve to be in a non-designed state, thereby blocking the test process. To achieve the above purpose, the present invention proposes a hydraulic fracturing in-situ stress measurement device, and the specific scheme is as follows:

[0006] A hydraulic fracturing in-situ stress measurement device includes: a water inlet module, a control valve, a sealing module, and a water passing valve that are connected in sequence;

[0007] The water inlet module is connected to the top of the control valve;

[0008] A fluid switching component is provided in the control valve for switching fluid channels to realize the switching of water gushing discharge and water injection paths;

[0009] A first channel and a second channel are provided at the bottom of the control valve; the first channel penetrates through the test section of the sealing module and is connected to the water passing valve, and is used for discharging the gushing water outside the control valve under the water gushing condition or injecting water into the test section under the water injection condition;

[0010] The second channel injects water into two sets of expandable packers of the packer module to cause them to expand and form the test section;

[0011] The test section is used to withstand high-pressure water under the water injection condition to generate rock formation fractures, and the water pressure data is monitored in real time by a pressure sensor to calculate the in-situ stress parameters;

[0012] The bottom of the water passing valve is provided with an openable and closable cover plate, and is communicated with the first channel and the second channel. The cover plate is opened under the water gushing condition or closed under the water injection condition.

[0013] Preferably, the fluid switching assembly includes: a compartment structure, a first fluid switching module, and a second fluid switching module;

[0014] The compartment structure divides the inner part of the valve body of the control valve into multiple compartments for distributing fluid paths;

[0015] The first fluid switching module is used to control the conduction of the water injection path between the second channel and the packer, or the conduction of the water injection path between the water inlet module and the test section;

[0016] The second fluid switching module is used to control the conduction of the drainage path between the first channel and the drain tank, or the conduction of the water injection path between the first channel and the test section.

[0017] Preferably, the compartment structure specifically includes: an upper partition plate, a middle partition plate, and a lower partition plate;

[0018] The upper partition plate, the middle partition plate, and the lower partition plate divide the valve body into a first compartment, a second compartment, a third compartment, and a fourth compartment from top to bottom;

[0019] The first compartment is communicated with the fourth compartment through a valve wall hole, the second compartment is communicated with the second channel, and a drain tank is provided on the side wall of the third compartment.

[0020] Preferably, the first fluid switching module includes: a first hollow valve stem, a first elastic member, and a first through hole;

[0021] The first end of the first hollow valve stem is communicated with the water inlet module, and the second end slidably penetrates through the first compartment and the second compartment;

[0022] The first elastic member connects the middle partition plate and the second end of the first hollow valve stem;

[0023] The first through hole is provided on the side wall of the first hollow valve stem and is used to switch to the second compartment or the first compartment under the action of the first elastic member to conduct the second channel and the packer or the water inlet module and the test section.

[0024] Preferably, the second fluid switching module includes: a second hollow valve stem, a second elastic member, a second through hole, and a third through hole;

[0025] The first end of the second hollow valve stem communicates with the first channel, and the second end slidably penetrates through the third housing and the fourth housing;

[0026] The second elastic member connects the middle partition plate and the second end of the second hollow valve stem;

[0027] The second through hole and the third through hole are axially provided on the side wall of the second hollow valve stem; the second through hole is used to switch to the third housing under the action of the second elastic member to conduct the first channel and the drain groove;

[0028] The third through hole is used to switch to the fourth housing under the action of the second elastic member to conduct the first channel and the test section.

[0029] Preferably, the water passing valve includes: a high-pressure water driving component and a water discharge channel;

[0030] The top of the water passing valve communicates with the first channel;

[0031] The high-pressure water driving component communicates with the second channel and is used to control the closing of the cover plate through high-pressure water;

[0032] The water discharge channel is used to introduce the gushing water into the first channel for upward drainage when the gushing water in the drill hole impacts and opens the cover plate by communicating the first channel with the water inlet at the bottom of the water passing valve.

[0033] Preferably, the high-pressure water driving component includes an axial hydraulic rod and a pull rod;

[0034] One end of the axial hydraulic rod communicates with the second channel, and the other end is hinged to the cover plate through the pull rod;

[0035] When high-pressure water pushes the axial hydraulic rod, the pull rod drives the cover plate to close to seal the water inlet.

[0036] Preferably, it further includes a filter;

[0037] The filter is arranged between the water inlet module and the control valve and is used to filter the high-pressure water.

[0038] Preferably, at least two levels of detachable filter cups are arranged in the filter.

[0039] Preferably, the water inlet module includes a high-pressure water pump and a drill pipe;

[0040] The high-pressure water pump communicates with the drill pipe;

[0041] The drill pipe is connected to the control valve and is used to supply high-pressure water to the control valve.

[0042] Advantages: (1) In the water gushing borehole of the present invention, the water gushing in the borehole can be discharged through the water passing valve and the control valve, thus solving the problem that the equipment cannot be normally lowered due to the water gushing in the borehole.

[0043] (2) The filter proposed by the present invention can filter the impurities in the high-pressure water, preventing the problem that the impurities in the high-pressure water block the control valve and the lower device, and it is convenient to disassemble and wash, and is convenient, fast and easy to use.

[0044] (3) The working principle of the control valve proposed by the present invention is different from that of the conventional push-pull valve, and it can avoid the problem that the conventional push-pull valve cannot open under the upward acting force of the water pressure in the borehole. This control valve is not affected by the lower pressure water, and the controllability is greatly improved. Description of the Drawings

[0045] Figure 1 It is a schematic diagram of the overall structure of the measuring device in the embodiment of the present invention;

[0046] Figure 2 It is a schematic diagram of the structure of the control valve in the embodiment of the present invention, where (a) is the front view of the control valve, and (b) is the longitudinal sectional view of the control valve;

[0047] Figure 3 It is the longitudinal sectional view of the control valve in two states in the embodiment of the present invention, where (c) is the sectional view of the control valve in the natural state, and (d) is the sectional view of the control valve in the stretched state;

[0048] Figure 4 It is the longitudinal sectional view of the water passing valve in the embodiment of the present invention;

[0049] Figure 5 It is the longitudinal sectional view of the water passing valve in two states in the embodiment of the present invention, where (e) is the sectional view of the water passing valve when the cover plate is opened, and (f) is the sectional view of the water passing valve in the sealed state;

[0050] Figure 6 It is the longitudinal sectional view of the filter in the embodiment of the present invention.

[0051] In the figure: 1. High-pressure water pump; 2. First high-pressure water pipe; 3. Sensor and ground pipeline control system; 4. Data collector; 5. Derrick; 6. Handle; 7. Top joint; 8. Drilling rig; 9. Test borehole; 10. Drill pipe; 11. Filter; 1101. Shell; 1102. Threaded screw; 1103. Upper filter cup; 1104. Middle filter cup; 1105. Lower filter cup; 1106. Large water filter hole; 1107. Medium water filter hole; 1108. Small water filter hole; 12. Control valve; 1201. Upper partition; 1202. Middle partition; 1203. Lower partition; 1204. Valve bottom interface; 1205. Drainage groove; 1206. First hollow valve stem; 1207. First spring; 1208. First through hole; 1209. First water stop pad; 1210. Second hollow valve stem; 1211. Second spring; 1212. Second through hole; 1213. Third through hole; 1214. Second water stop pad; 13. Packer; 14. Hollow connecting rod; 15. Water permeable hole; 16. Second high-pressure water pipe; 17. Water passing valve; 1701. High-pressure water pipe interface; 1702. Water inlet channel; 1703. Third high-pressure water pipe; 1704. Cross beam; 1705. Axial hydraulic rod; 1706. Pull rod; 1707. Cover plate; 1708. Third spring; 1709. Water inlet; 1710. Water stop gasket. Detailed implementation mode

[0052] To make the purpose, technical solution and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with specific implementation modes. It should be understood that the specific implementation modes described here are only used to explain the present invention and do not limit the protection scope of the present invention.

[0053] A water pressure-induced fracturing in-situ stress measurement device includes: a water inlet module, a control valve 12, a sealing module and a water passing valve 17 that are connected in sequence;

[0054] The water inlet module is connected to the top of the control valve 12;

[0055] A fluid switching component is provided inside the control valve 12 for switching fluid channels to realize the switching of water gushing discharge and water injection paths;

[0056] A first channel and a second channel are provided at the bottom of the control valve 12;

[0057] The first channel penetrates through the test section of the sealing module and is connected to the water passing valve 17, and is used to discharge the gushing water outside the control valve 12 under the water gushing condition or inject water into the test section under the water injection condition;

[0058] The second channel injects water into two groups of expandable packers 13 of the sealing module to make them expand to form a test section;

[0059] The test section is used to withstand high-pressure water under the water injection condition to generate rock formation fractures, and the water pressure data is monitored in real time through a pressure sensor to calculate the in-situ stress parameters;

[0060] A closable cover plate 1707 is provided at the bottom of the water passing valve 17, which is connected to the first channel and the second channel. The cover plate 1707 is opened under the condition of water gushing, or closed under the condition of water injection.

[0061] As Figure 1 As shown, in addition to the measuring devices in the underground part, the present invention further includes surface equipment, specifically including sensors (including pressure sensors and flow sensors), a ground pipeline control system, a data acquisition instrument 4, a drill tower 5, a handle 6, and a top joint 7. The ground pipeline control system is used to control the delivery of high-pressure water source; the data acquisition instrument 4 is responsible for receiving and recording the data transmitted by the sensors; the drill tower 5 is used in cooperation with the drill rig 8 to lift and lower the water inlet module and the entire measuring device; the handle 6 is connected to the top joint 7 of the measuring device to facilitate the lifting or lowering of the device; the top joint 7 is connected to both the handle 6 and the water inlet module to ensure the smooth input of high-pressure water. During use, first, a test borehole 9 to be tested is drilled through the cooperation of the drill rig 8 and the drill tower 5. Then, the measuring device is lifted or lowered to a specified position in the test borehole 9 through the cooperation of the drill tower 5. Next, the high-pressure water pump 1 is started, and high-pressure water is provided to the control valve 12 through the drill pipe 10. According to the test requirements, the fluid channel is switched through the fluid switching component in the control valve 12 to achieve the operation of water gushing discharge or water injection. Under the water injection condition, the packer 13 expands and seals to form a test section, and then high-pressure water is injected into the test section to generate rock formation fractures. At the same time, the water pressure data is monitored in real time through the pressure sensor, and finally the in-situ stress parameters are calculated. It should be noted that the first channel at the bottom of the control valve 12 is specifically a hollow connecting rod 14, the second channel is specifically a second high-pressure water pipe 16, and the hollow connecting rod 14 is provided with water permeable holes 15 at the position located in the test section for injecting the high-pressure water in the rod into the test section.

[0062] In an embodiment of the present invention, the water inlet module includes a high-pressure water pump 1 and a drill pipe 10;

[0063] The high-pressure water pump 1 is connected to the drill pipe 10;

[0064] The drill pipe 10 is connected to the control valve 12 and is used to provide high-pressure water to the control valve 12.

[0065] In this embodiment, the high-pressure water pump 1 is used to provide a high-pressure water source for the test. One end of the drill pipe 10 is connected to the control valve 12, and the other end is connected to the high-pressure water pump 1 through the first high-pressure water pipe 2. The drill pipe 10 serves as an overcurrent channel for high-pressure water to provide high-pressure water to the control valve 12, and the length of the drill pipe 10 is determined according to the measurement depth.

[0066] Further, the fluid switching assembly includes: a compartmentalized structure, a first fluid switching module, and a second fluid switching module;

[0067] The compartmentalized structure divides the interior of the valve body of the control valve 12 into multiple compartments for distributing fluid paths;

[0068] The first fluid switching module is used to control the conduction of the second channel and the water injection path of the packer 13, or the conduction of the water inlet module and the water injection path of the test section;

[0069] The second fluid switching module is used to control the conduction of the first channel and the drainage path of the drain tank 1205, or the conduction of the first channel and the water injection path of the test section.

[0070] Specifically, in the hydraulic fracturing in-situ stress measurement device of the present invention, the fluid switching assembly is responsible for switching fluid paths to meet the different requirements of water inrush discharge and water injection operations. The fluid switching assembly mainly consists of a compartmentalized structure, a first fluid switching module, and a second fluid switching module.

[0071] The compartmentalized structure is designed inside the valve body of the control valve 12, dividing the valve body into multiple independent compartments. These compartments each undertake different fluid path distribution tasks, ensuring the orderly flow of fluid within the control valve 12. It can effectively avoid the crossing and interference of fluid paths, improving the accuracy and reliability of fluid switching. The first fluid switching module is a key component for controlling the fluid flow to the packer 13 or the test section. When it is necessary to inject water into the packer 13 to form the test section, the first fluid switching module will conduct the second channel and the water injection path of the packer 13, enabling high-pressure water to be smoothly injected into the packer 13 and causing it to expand. When it is necessary to inject water into the test section for hydraulic fracturing testing, the first fluid switching module will switch to the water injection path between the water inlet module and the test section to ensure that high-pressure water can accurately reach the test section. The second fluid switching module is responsible for controlling the fluid flow of the first channel. Under the water inrush condition, in order to smoothly discharge the water inrush outside the control valve 12, the second fluid switching module will conduct the first channel and the drainage path of the drain tank 1205. Under the water injection condition, in order to prevent high-pressure water leakage, the second fluid switching module will close the drainage path and conduct the first channel and the water injection path of the test section to ensure that high-pressure water can smoothly enter the test section for hydraulic fracturing testing.

[0072] The fluid switching assembly enables the hydraulic fracturing in-situ stress measurement device of the present invention to flexibly switch fluid paths to meet the different requirements of water inrush discharge and water injection operations. At the same time, by precisely controlling the fluid flow direction and flow rate, the accuracy and reliability of the test results can be ensured.

[0073] The compartmentalized structure of the embodiment of the present invention specifically includes: an upper partition plate 1201, a middle partition plate 1202, and a lower partition plate 1203;

[0074] The upper partition plate 1201, the middle partition plate 1202 and the lower partition plate 1203 divide the valve body into a first chamber, a second chamber, a third chamber and a fourth chamber from top to bottom;

[0075] The first chamber communicates with the fourth chamber through a valve wall hole, the second chamber communicates with the second channel, and a water discharge groove 1205 is provided on the side wall of the third chamber.

[0076] Specifically, in this embodiment, the second chamber is specifically communicated with the valve bottom interface 1204 at the bottom of the control valve 12, and the valve bottom interface 1204 communicates with the second channel. In this embodiment, the second channel is the second high-pressure water pipe 16. A water discharge groove 1205 is provided on the side wall of the third chamber, and the water discharge groove 1205 is used to discharge the gushing water outside the control valve 12 under the gushing water condition.

[0077] The first fluid switching module of the embodiment of the present invention includes: a first hollow valve stem 1206, a first elastic member and a first through hole 1208;

[0078] The first end of the first hollow valve stem 1206 communicates with the water inlet module, and the second end slidably penetrates through the first chamber and the second chamber;

[0079] The first elastic member connects the middle partition plate 1202 and the second end of the first hollow valve stem 1206;

[0080] The first through hole 1208 is provided on the side wall of the first hollow valve stem 1206 and is used to switch to the second chamber or the first chamber under the action of the first elastic member to conduct the second channel and the packer 13 or the water inlet module and the test section.

[0081] The second fluid switching module of the embodiment of the present invention includes: a second hollow valve stem 1210, a second elastic member, a second through hole 1212 and a third through hole 1213;

[0082] The first end of the second hollow valve stem 1210 communicates with the first channel, and the second end slidably penetrates through the third chamber and the fourth chamber;

[0083] The second elastic member connects the middle partition plate 1202 and the second end of the second hollow valve stem 1210;

[0084] The second through hole 1212 and the third through hole 1213 are axially provided on the side wall of the second hollow valve stem 1210; the second through hole 1212 is used to switch to the third chamber under the action of the second elastic member to conduct the first channel and the water discharge groove 1205;

[0085] The third through hole 1213 is used to switch to the fourth chamber under the action of the second elastic member to conduct the first channel and the test section.

[0086] Specifically, as Figures 2 - 3As shown, in the present invention, the first elastic member and the second elastic member are both springs, denoted as the first spring 1207 and the second spring 1211. The first spring 1207 and the second spring 1211 are in a contracted state in their natural state. At this time, the state of the control valve 12 is denoted as the natural state. Conversely, when the first spring 1207 and the second spring 1211 are in a stretched state, the state of the control valve 12 is denoted as the stretched state. When the control valve 12 is in the natural state, the first fluid switching module and the second fluid switching module conduct the first channel and the drain tank 1205, and also conduct the second channel and the packer 13; realizing the inflation of the packer 13 during the stage of lowering the measuring device for water gushing discharge and measurement preparation. When the control valve 12 is in the stretched state, the first fluid switching module conducts the water inlet module and the first chamber, and the second fluid switching module conducts the fourth chamber and the first channel, realizing the conduction of the water injection path in the test section.

[0087] In this embodiment, the first hollow valve stem 1206 and the second hollow valve stem 1210 are both designed as bolt-shaped rods with a hollow structure. Their second ends are designed in a protruding form to prevent exceeding the predetermined stroke range when sliding inside the control valve 12. Specifically, a first water stop pad 1209 is assembled at a position adjacent to the upper partition plate 1201 at the protruding end of the first hollow valve stem 1206, while a second water stop pad 1214 is provided at a position adjacent to the lower partition plate 1203 at the protruding end of the second hollow valve stem 1210. The first water stop pad 1209 and the second water stop pad 1214 are used to ensure the sealing performance of the control valve 12.

[0088] It should be noted that, as Figure 2 shown, the second through hole 1212 and the third through hole 1213 are respectively arranged along the axial direction of the second hollow valve stem 1210. The sliding position of the second hollow valve stem 1210 will determine the communication state of these through holes. Specifically: when the control valve 12 is in the natural state, the second through hole 1212 is connected to the inside of the third chamber, allowing the gushing water to pass through this channel; while when the control valve 12 is in the stretched state, the second through hole 1212 will be blocked by the lower partition plate 1203, thereby preventing the flow of fluid.

[0089] In this embodiment, the third through hole 1213 is designed to always maintain communication with the fourth chamber during the sliding process of the second hollow valve stem 1210. This is because when the control valve 12 is in the natural state, the preparation work for water gushing discharge or packer 13 injection is usually carried out. At this time, the first chamber is in a closed state and does not participate in the current fluid path. Therefore, the fluid state in the fourth chamber connected to the first chamber through the valve wall hole has no direct impact on the current fluid path selection. Based on this principle, the third through hole 1213 is designed to maintain communication with the fourth chamber throughout the entire movement range of the control valve 12, including when the control valve 12 is in the natural or stretched state. Of course, according to specific design requirements of those skilled in the art, the third through hole 1213 may also be blocked by the lower partition 1203 when the control valve 12 is in the natural state.

[0090] When the control valve 12 is in the natural state, the first through hole 1208 is located in the second chamber, and the second through hole 1212 is located in the third chamber. At this time, when the measuring device is lowered, the gushing water enters the third chamber through the water passing valve 17 and the first channel communicating with the water passing valve 17, and then is discharged from the control valve 12 through the water discharge groove 1205 on the side wall of the third chamber, realizing the conduction and discharge of the gushing water in the borehole and solving the problem that the measuring device cannot be normally lowered due to the gushing water in the hole.

[0091] When entering the measurement preparation stage, that is, when the measuring device is lowered to the preset position, the gushing water discharge ends. The high-pressure water pump 1 supplies water to the control valve 12. The water flow enters the second chamber through the first through hole 1208. Since the second chamber is connected to the second high-pressure water pipe 16 through the valve bottom interface 1204, the water flow enters the second high-pressure water pipe 16 to supply water to the packer 13 to make it expand to form a test section. At the same time, the water flow enters the water passing valve 17 and drives the cover plate 1707 of the water passing valve 17 to close.

[0092] When the measurement preparation stage ends, that is, when the expansion of the packer 13 meets the preset requirements, the drill pipe 10 is lifted to make the control valve 12 in the stretched state. At this time, the first through hole 1208 is located in the first chamber, the second through hole 1212 is closed, and the third through hole 1213 is located in the fourth chamber. The high-pressure water pumped out by the high-pressure water pump 1 enters the first chamber and the fourth chamber of the control valve 12 through the first hollow valve stem 1206 and the first through hole 1208, and then enters the second hollow valve stem 1210 and the first channel through the third through hole 1213 to enter the test section, and then high-pressure water is injected into the test section for in-situ stress measurement.

[0093] The water passing valve 17 of the embodiment of the present invention includes: a high-pressure water driving component and a water discharge channel;

[0094] The top of the water passing valve 17 is connected to the first channel;

[0095] The high-pressure water driving assembly is connected to the second channel and is used to control the closing of the cover plate 1707 through high-pressure water;

[0096] The water discharge channel is connected to the first channel and the water inlet 1709 at the bottom of the water passing valve 17, and is used to guide the gushing water into the first channel for upward discharge when the gushing water in the borehole impacts and opens the cover plate 1707.

[0097] In this embodiment, the high-pressure water driving assembly is connected to the second channel and is used to control the closing of the bottom cover plate 1707 of the water passing valve 17, so as to form a sealed water storage space with the packer 13 to ensure the stability of the test section.

[0098] The high-pressure water driving assembly of the embodiment of the present invention includes an axial hydraulic rod 1705 and a pull rod 1706;

[0099] One end of the axial hydraulic rod 1705 is connected to the second channel, and the other end is hinged to the cover plate 1707 through the pull rod 1706;

[0100] When the high-pressure water pushes the axial hydraulic rod 1705, the pull rod 1706 drives the cover plate 1707 to close to seal the water inlet 1709.

[0101] Specifically, in this embodiment, as Figure 4 shown, the cover plate 1707 includes two hinged semi-circular lower cover plates 1707. A water stop gasket 1710 is provided at the end of the cover plate 1707. The two cover plates 1707 are connected by a third spring 1708, so that the cover plate 1707 is in an open state under normal conditions. Of course, in other embodiments, the third spring 1708 may not be used, and the cover plate 1707 is pushed open by the action force of the gushing water. The axial hydraulic rod 1705 is fixed on the cross beam 1704 in the water passing valve 17, and one end of it is connected to the second high-pressure water pipe 16 through the third high-pressure water pipe 1703, and the other end is hinged to the lower cover plate 1707 through the pull rod 1706; as Figure 4 and Figure 5 shown, specifically, a water inlet channel 1702 is provided at the top of the water passing valve 17. A high-pressure water pipe interface 1701 is provided on one side of the outer wall of the water passing valve 17 for the water inlet channel 1702, and the high-pressure water pipe interface 1701 is connected to the second high-pressure water pipe 16. The water inlet channel 1702 is connected to the third high-pressure water pipe 1703 on one side of the inner wall of the water passing valve 17. When high-pressure water is injected into the third high-pressure water pipe 1703, the axial hydraulic rod 1705 pushes the pull rod 1706 to close the cover plate 1707 to seal the water inlet 1709; when the high-pressure water is removed, the third spring 1708 resets the cover plate 1707 to the open state, and the water inlet 1709 conducts the water discharge channel.

[0102] The embodiment of the present invention further includes a filter 11;

[0103] The filter 11 is arranged between the water inlet module and the control valve 12 and is used to filter high-pressure water.

[0104] Specifically, at least two levels of detachable filter cups are arranged in the filter 11.

[0105] The filter 11 is arranged between the water inlet module and the control valve 12. As Figure 6 shown, specifically, its top is connected to the drill pipe 10 through a threaded screw port 1102, and the bottom is communicated with the control valve 12; three levels of detachable filter cups are arranged in the filter 11 for grading filtration of high-pressure water. The outer shell 1101 of the filter 11 is cylindrical, and its wall thickness gradually thickens in a stepped manner from top to bottom. The wall thickness of the outer shell 1101 is divided into three levels from top to bottom, corresponding to the installation positions of the upper, middle, and lower filter cups respectively, and the wall thickness increases by 2 mm - 3 mm for each level. Specifically, the filter cups include an upper filter cup 1103, a middle filter cup 1104, and a lower filter cup 1105 arranged from top to bottom. The three are detachably connected to the inside of the outer shell 1101 by clamping or threading; the pore diameters of the water filtering holes of each filter cup gradually decrease from top to bottom, forming a multi-level filtering structure. The water filtering holes of the upper filter cup 1103 are large water filtering holes 1106; the water filtering holes of the middle filter cup 1104 are medium water filtering holes 1107; the water filtering holes of the lower filter cup 1105 are small water filtering holes 1108.

[0106] The working principle and usage process of the measuring device of the present invention are as follows:

[0107] First, after the test borehole 9 is completed, select an appropriate measuring depth and determine the length of the drill pipe 10 to ensure that the test can be carried out for a predetermined geological layer.

[0108] Subsequently, through the handle 6, the water passing valve 17, the second high-pressure water pipe 16, the packer 13, the control valve 12, the filter 11, and the drill pipe 10 are successively connected and lowered into the hole. Different lengths of the drill pipe 10 can be used for different measuring depths until it is lowered to the specified depth. During the lowering process, the bottom cover plate 1707 of the water passing valve 17 is in an open state, and the gushing water enters the control valve 12 through the water inlet 1709, then enters the control valve 12 after entering the hollow connecting rod 14 serving as the first channel, and is discharged from the control valve 12 after passing through the second hollow valve rod 1210, the second through hole 1212, and the water discharge groove 1205, ensuring that the device can be smoothly lowered to the specified depth.

[0109] After the device is lowered to the predetermined measurement depth, the surface equipment is connected: top joint 7, sensor and surface pipeline control system 3, data acquisition instrument 4, first high-pressure water pipe 2, high-pressure water pump 1. After the connection is completed, the high-pressure water pump 1 is turned on, the surface pipeline control system is adjusted, and high-pressure water is pumped into the underground measurement device (the control valve 12 is in a natural state). The high-pressure water enters the control valve 12 through the drill pipe 10 and the filter 11, and enters the second chamber of the control valve 12 through the first hollow valve stem 1206 and the first through hole 1208. The second chamber is connected to the valve bottom interface 1204. After passing through the valve bottom interface 1204, it enters the packer 13 and the water valve 17 in sequence through the second high-pressure water pipe 16. The packer 13 expands under the action of high-pressure water, and the two packers 13 are closely attached to the borehole wall, forming a closed test section between them. When high-pressure water is pumped into the water valve 17, the axial hydraulic rod 1705 moves downward, pushing the pull rod 1706, driving the lower cover plate 1707 downward until it contacts the inner wall. At this time, the cover plate 1707 is closed and the water valve 17 is in a sealed state.

[0110] Next, the drill pipe 10 is slightly lifted by the handle 6 and the top joint 7. Since the expanded packer 13 fits tightly against the borehole wall, the equipment below the control valve 12 is fixed. The lifting causes the first spring 1207 and the second spring 1211 inside the control valve 12 to be in a stretched state. At this time, the control valve 12 is in a stretched state, and then high-pressure water is pumped in. It passes through the first hollow valve stem 1206 and the first through hole 1208 and enters the first chamber of the control valve 12. The first chamber is connected to the fourth chamber, and the high-pressure water enters the fourth chamber, and then enters the second hollow valve stem 1210 through the third through hole 1213, and then enters the hollow connecting rod 14 as the second channel. Since the water valve 17 is sealed at this time, the high-pressure water enters the test section from the water permeable hole 15 of the connecting rod.

[0111] The test section is pressurized with a high-pressure water pump 1, and the pressure-flow-time curve is collected through the ground pipeline control system and the ground data acquisition system. Parameters such as splitting pressure, reopening pressure, and closing pressure are selected on the curve to measure the ground stress.

[0112] After the measurement is completed, the high-pressure water pump 1 is turned off, and the high-pressure water in the test section flows back. After the test section is depressurized, the drill pipe 10 is lowered through the handle 6 and the top joint 7. At this time, the first spring 1207 and the second spring 1211 inside the control valve 12 shrink to put it in a natural state. The high-pressure water is discharged from the water valve 17 and the packer 13 to the control valve 12, enters the second chamber through the valve bottom interface 1204, and is discharged to the drill pipe 10 through the first through hole 1208, so that the packer 13 is depressurized.

[0113] After the packer 13 is depressurized, it returns to its original state. After the water passing valve 17 is depressurized, its lower cover plate 1707 opens. The equipment can move freely. Repeat the above steps and continue to perform tests at other depths.

[0114] In the water gushing borehole of the present invention, the water gushing in the borehole can be discharged through the water passing valve 17, the hollow connecting rod 14, and the control valve 12, thus solving the problem that the equipment cannot be normally lowered due to the water gushing in the borehole. The filter 11 proposed by the present invention can filter the impurities in the high-pressure water, preventing the problem that the impurities in the high-pressure water block the control valve 12 and the lower devices, and it is also convenient for disassembly and cleaning, and is convenient and fast to use. The working principle of the control valve 12 proposed by the present invention is different from that of the conventional push-pull valve, and it can avoid the problem that the conventional push-pull valve cannot open under the upward acting force of the water pressure in the borehole. This control valve 12 is not affected by the lower pressure water, and the controllability is greatly improved. The present invention can be used not only in water gushing boreholes, but also in conventional boreholes. When the water level in the borehole is relatively deep, no separate pressure relief device is required, and the applicability is strong.

[0115] The above are only several embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention is disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art, without departing from the scope of the technical solution of the present invention, makes some changes or modifications using the technical content disclosed above, which are equivalent to equivalent implementation cases and all belong to the scope of the technical solution.

Claims

1. A hydraulic fracturing in-situ stress measurement device, characterized in that, Comprising: An inlet module, a control valve, a packer module, and a water passing valve that are connected in sequence; The inlet module is connected to the top of the control valve; A fluid switching component is provided inside the control valve for switching fluid channels to achieve the switching of water gushing discharge and injection paths; A first channel and a second channel are provided at the bottom of the control valve; The first channel penetrates through the test section of the packer module and is connected to the water passing valve, and is used to discharge the gushing water outside the control valve under the water gushing condition or inject water into the test section under the water injection condition; The second channel injects water into two sets of expandable packers of the packer module to make them expand to form the test section; The test section is used to withstand high-pressure water to generate rock formation fractures under the water injection condition, and the water pressure data is monitored in real time by a pressure sensor to calculate the in-situ stress parameters; A closable cover plate is provided at the bottom of the water passing valve and is connected to the first channel and the second channel. The cover plate is opened under the water gushing condition or closed under the water injection condition; The fluid switching component includes: a compartment structure, a first fluid switching module, and a second fluid switching module; The compartment structure divides the inner part of the valve body of the control valve into multiple compartments for distributing fluid paths; The first fluid switching module is used to control the conduction of the water injection path between the second channel and the packer, or the conduction of the water injection path between the inlet module and the test section; The second fluid switching module is used to control the conduction of the drainage path between the first channel and the drain tank, or the conduction of the water injection path between the first channel and the test section; The water passing valve includes: a high-pressure water driving component and a drainage channel; The top of the water passing valve is connected to the first channel; The high-pressure water driving component is connected to the second channel and is used to control the closing of the cover plate through high-pressure water; The drainage channel is used to introduce the gushing water into the first channel for upward drainage when the cover plate is opened by the impact of the gushing water in the borehole by connecting the first channel and the water inlet at the bottom of the water passing valve.

2. The hydraulic fracturing in-situ stress measurement device according to claim 1, characterized in that, The compartment structure specifically includes: an upper partition board, a middle partition board, and a lower partition board; The upper partition board, the middle partition board, and the lower partition board divide the valve body into a first compartment, a second compartment, a third compartment, and a fourth compartment from top to bottom; The first compartment is connected to the fourth compartment through a valve wall hole, the second compartment is connected to the second channel, and a drain tank is provided on the side wall of the third compartment; 3. The hydraulic fracturing in-situ stress measurement device according to claim 2, wherein The first fluid switching module includes: a first hollow valve rod, a first elastic member, and a first through hole; The first end of the first hollow valve rod is connected to the inlet module, and the second end slides through the first compartment and the second compartment; The first elastic member connects the middle partition board and the second end of the first hollow valve rod; The first through hole is provided on the side wall of the first hollow valve rod and is used to switch to the second compartment or the first compartment under the action of the first elastic member to conduct the second channel and the packer or the inlet module and the test section; 4. The hydraulic fracturing in-situ stress measurement device according to claim 2, characterized in that, The second fluid switching module includes: a second hollow valve rod, a second elastic member, a second through hole, and a third through hole; The first end of the second hollow valve rod is connected to the first channel, and the second end slides through the third compartment and the fourth compartment; The second elastic member connects the middle partition board and the second end of the second hollow valve rod; The second through-hole and the third through-hole are axially arranged on the side wall of the second hollow valve stem; The second through-hole is used to switch to the third cavity under the action of the second elastic member to conduct the first channel and the water discharge groove; The third through-hole is used to switch to the fourth cavity under the action of the second elastic member to conduct the first channel and the test section.

5. The hydraulic fracturing in-situ stress measurement device according to claim 1, characterized in that The high-pressure water driving assembly includes an axial hydraulic rod and a pull rod; One end of the axial hydraulic rod is communicated with the second channel, and the other end is hinged to the cover plate through the pull rod; When high-pressure water pushes the axial hydraulic rod, the pull rod drives the cover plate to close to seal the water inlet.

6. The hydraulic fracturing in-situ stress measurement device according to claim 1, wherein, It further includes a filter; The filter is arranged between the water inlet module and the control valve and is used to filter high-pressure water.

7. The hydraulic fracturing in-situ stress measurement device according to claim 6, characterized in that, At least two levels of detachable filter cups are arranged in the filter.

8. The hydraulic fracturing in-situ stress measurement device according to claim 1, characterized in that The water inlet module includes a high-pressure water pump and a drill pipe; The high-pressure water pump is communicated with the drill pipe; The drill pipe is communicated with the control valve and is used to supply high-pressure water to the control valve.

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