Linkage type hydraulic fracturing method ground stress testing device and testing methodTechnical Field
The invention belongs to the technical field of rock mass mechanics testing, and particularly relates to a linkage hydraulic fracturing method ground stress testing device and a testing method.
Background
Conventional hydraulic fracturing method ground stress tests are largely classified into single tube method and double tube method. The single-pipe method realizes the pressure channel switching of the packer and the test section by inscribing the push-pull valve between the drill rod and the double-plug packer, is suitable for continuous and rapid test of deep drilling at high water level (the water level is not more than 50m generally), and has simple operation. The double-pipe method forms two pressure channels through connecting the slender high-pressure water pipe with the drill pipe externally to the packer, is suitable for shallow drilling test and is complex in operation. With the increasing of the buried depth of underground engineering, geological drilling with large buried depth and deep water level can be commonly found, a single pipe method is generally selected for testing, but pressure formed by the difference between the water heads inside and outside a drill rod in the process of injecting water into the drill rod can cause the packer to be automatically expanded and fixed on the hole wall and cannot move, so that the packer is required to be independently decompressed by a matched decompression device, the efficiency of the existing decompression method is lower, and the required testing time is long enough for drilling with ultra-high water level.
At present, the pressure relief mode with higher operability mainly comprises two modes, namely, a first pressure relief mode can not be continuously tested after the pressure of a packer is relieved, a packer is required to be lifted to the ground completely through a drill rod after one test section is completed, the pressure relief device is manually restored, then the drill rod is connected again, lifted through a drilling machine, lowered to a designated position and filled with water again through the drill rod, the pressure relief mode is lowest in efficiency, a great amount of time and manpower are used for connecting and disassembling the drill rod in a repeated lifting process and filling water before testing, and a second pressure relief mode is used for finely adjusting the stroke of a piston in the pressure relief device through accurately controlling the lifting of the drill rod on the ground so that water in the drill rod flows into a drilled hole, the head difference between the inside and the outside of the drill rod is reduced, the purpose of pressure relief of the packer is achieved, the pressure relief of the packer can be continuously tested through lifting of the drill rod to be carried out at the next test position after pressure relief, but water is required to be filled into the drill rod again before test, the pressure relief mode is improved compared with the first mode in efficiency, the drill rod is not required to be lifted repeatedly, and the water is still required to occupy a long time before the pressure relief process and retest. The two modes achieve the aim of pressure relief, but the efficiency is very low, and clean water resources on a test site are often scarce, so that the hydraulic fracturing ground stress testing device and the hydraulic fracturing ground stress testing method which are suitable for deep drilling, low in water level, efficient and easy to operate have important significance in order to save time, labor and material resource investment, improve testing efficiency and reduce testing cost.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides a linkage hydraulic fracturing ground stress testing device which can adjust a pressure relief device to perform water injection or pressure relief only by controlling a drill rod, so that the purposes of quickly relieving pressure of a packer and saving the water head of the drill rod and switching pressure channels in deep drilling low water level testing are realized.
In order to solve the technical problems, the invention adopts the following technical scheme:
the utility model provides a coordinated type hydraulic fracturing method crustal stress testing arrangement, testing arrangement includes pressure relief device, goes up the packer of being connected through first pipeline with pressure relief device and passes through the lower packer of second pipeline intercommunication with last packer, wherein, pressure relief device includes:
The upper valve body is connected with the drill rod during testing and comprises a first shell and a limiting device, a first inner cavity which extends along the axial direction of the first shell and is communicated with the drill rod, a first water outlet hole and a second water outlet hole which are communicated with the first inner cavity are formed in the first shell, a first channel and a second channel are formed in the limiting device, the first water outlet hole, the second water outlet hole, the first channel and the second channel are not communicated with each other, the limiting device is arranged in the first inner cavity and can selectively move in the first inner cavity, when the limiting device is fixed in the first inner cavity, the first channel is communicated with the first water outlet hole, and when the limiting device moves to a limiting position in the first inner cavity, the first water outlet hole, the second channel and the second water outlet hole are sequentially communicated with each other;
The base is elastically connected with the first shell, and is also connected with the limiting device, when the base and the first shell move away from each other to a limit position, the limiting device moves in the first inner cavity under the action of the base, and a third channel is further arranged in the base, and one end of the third channel is connected with the first water outlet through a third pipeline;
The lower valve body comprises a second shell and a lower valve body piston connected with the base, a second inner cavity and a third water outlet are arranged in the second shell, a central flow passage and a fourth water outlet communicated with the central flow passage are arranged in the lower valve body piston, the lower valve body piston is movably arranged in the second inner cavity, when the lower valve body piston moves to a limit position in the second inner cavity towards the direction of the base, the third water outlet is communicated with the fourth water outlet, when the lower valve body piston moves to the limit position in the second inner cavity towards the direction away from the base, the third water outlet is separated from the fourth water outlet and is not communicated with the fourth water outlet, the third water outlet is also communicated with the upper packer through a first pipeline, in addition, one end of the central pipeline away from the upper packer is a closed section, the central pipeline passes through the upper packer and the lower packer to connect the lower valve body, the upper packer and the lower packer, a test section is arranged on the central pipeline between the upper packer and the lower packer, when the lower valve body piston moves to the limit position in the second inner cavity towards the direction away from the base, the third water outlet is separated from the fourth water outlet, and the third water outlet is communicated with the central flow passage in turn from the central flow passage.
Further, stop device includes the first spring that one end is connected with last valve body, the last valve body piston of being connected with the first spring other end, sets up on first inner chamber lateral wall and be used for restricting the spacer pin that goes up valve body piston and one end and spacer pin are connected the other end and pedestal connection's connecting rope, and wherein, first passageway and second passageway set up on last valve body piston, are provided with the L shape mounting hole that is used for installing the spacer pin on the lateral wall of first casing still correspond on last valve body piston and be provided with the draw-in groove, under initial condition, the spacer pin inserts in the draw-in groove in order to fix last valve body piston from the mounting hole, pulls the connecting rope in order to extract the spacer pin from the draw-in groove, go up valve body piston and remove in first inner chamber under the effect of first spring, when the spacer pin card is gone into the draw-in groove, first spring is in tensile state.
Further, the first inner chamber includes first cavity and the second cavity of being connected with first cavity, the internal diameter of first cavity is greater than the internal diameter of second cavity, go up the valve body piston and be the T font, it includes first piston body and the second piston body of being connected perpendicularly with first piston body, wherein, first piston body adaptation is in first cavity, second piston body adaptation is in the second cavity, when last valve body piston moves to first piston body in first inner chamber and is located first cavity and second cavity junction, the draw-in groove aligns with the mounting hole, the spacer pin inserts in the draw-in groove from the mounting hole.
Further, a plurality of sealing rings are arranged on the inner wall of the first inner cavity at intervals, and the sealing rings are respectively used for blocking water flow in the first inner cavity from directly flowing into the first water outlet hole and blocking water flow between the first channel and the second channel.
Further, a push-pull device connected with the first spring is further arranged on the first shell, the push-pull device comprises a bolt, one end of the bolt penetrates through the first shell and is connected with one end of the first spring, a nut is connected with the bolt through threads, the nut is screwed, and the bolt compresses the first spring or stretches the first spring.
Further, the first casing with base elastic connection, elastic connection structure is including setting up the connector outer sleeve on first casing bottom surface, movably setting up at the inside baffle of connector outer sleeve, one end with the baffle is connected and the other end stretches out the connecting axle outside the connector outer sleeve and the cover is established on the connecting axle and one end is connected the other end with the baffle and is connected the second spring of connector outer sleeve, and downward valve body direction pulling connecting axle, the second spring is compressed, in addition, the other end and the pedestal connection of connecting axle.
Further, the lower valve body piston is provided with limit structure with the cooperation of second inner chamber, limit structure specifically does:
The second inner chamber includes the third cavity and the fourth cavity of being connected with the third cavity, and wherein the internal diameter of third cavity is less than the internal diameter of fourth cavity, lower valve body piston includes integrated into one piece's third piston body and fourth piston body, and the external diameter of third piston body is equivalent with the internal diameter of third cavity, and the external diameter of fourth piston body is equivalent with the internal diameter of fourth cavity, and the length of fourth cavity is greater than the length of fourth piston body, and the fourth piston body adaptation is in the fourth cavity and when the fourth piston body removes fourth cavity and third cavity junction, and lower valve body piston can't upwards move and is spacing any more, and at this moment, central runner, fourth apopore and third apopore communicate in proper order.
Further, a limiting plate is further arranged on the fourth piston body and used for limiting the maximum descending distance of the fourth piston body in the fourth cavity.
Further, a plurality of sealing rings are arranged on the inner wall of the second inner cavity at intervals, and are used for blocking water flow in the fourth water outlet hole from flowing into the third water outlet hole through the second cavity.
The invention also provides a testing method of the linkage hydraulic fracturing ground stress testing device, which comprises the following steps:
The method comprises the steps of 1, sequentially connecting a pressure relief device, an upper packer and a lower packer of a testing device, then connecting the pressure relief device with a drill rod, in an initial state, enabling the pressure relief device to be in a stretching state, enabling a limiting device to be fixed in a first inner cavity, enabling a first channel to be communicated with a first water outlet, enabling a lower valve body piston to be located at a limiting position far away from a base in a second inner cavity, enabling a third water outlet to be separated from a fourth water outlet, then lowering the testing device to a selected position in a drilling hole through the drill rod, enabling a lower valve body piston to move to a limiting position in the second inner cavity towards the base under the action of gravity in the lowering process, enabling a third water outlet to be communicated with the fourth water outlet, enabling high-pressure water to sequentially flow from the drill rod to the first inner cavity, the first channel, the first water outlet, a third pipeline, the third channel, a central flow channel, the fourth water outlet, the first pipeline, the upper packer, the second pipeline and the lower packer, and the upper packer to expand under the action of high-pressure water flow and form a test section under the action of the high-pressure water flow tightly attaching the upper packer and lower packer;
Step 2, pressing down a drill rod, wherein when a lower valve body piston moves to a limit position in a second inner cavity in a direction away from a base, a third water outlet is separated from a fourth water outlet and is not communicated with the fourth water outlet, high-pressure water in the drill rod flows into a second inner cavity below the fourth water outlet through a first inner cavity, a first channel, a first water outlet, a third pipeline, a third channel, a central flow channel and a fourth water outlet, flows into a central pipeline from the second inner cavity, and performs pressurized water injection on a selected test section through a test section water outlet on the central pipeline and tests;
Step 3, after the ground stress test of step 2 is finished, lifting the drill rod upwards, and as the upper packer and the lower packer are set, when the lower valve body piston moves to the limit position in the direction of the base in the second inner cavity, the third water outlet is communicated with the fourth water outlet, and the drill rod is continuously lifted until the limiting device moves to the limit position in the first inner cavity under the action of the base when the base moves away from the first shell to the limit position, wherein the second channel is communicated with the first water outlet, and water in the lower packer and the upper packer sequentially flows through the second pipeline, the first pipeline, the third water outlet, the fourth water outlet, the central flow channel, the third pipeline, the first water outlet and the second channel, flows into the first inner cavity and finally flows out of the second water outlet, and then the pressure in the upper packer and the lower packer is relieved;
And fourthly, after the pressure in the upper packer and the lower packer is completely unloaded, the base and the first shell are restored to an initial state under the action of elastic force, the drill rod is moved to the next selected test position, before the test, the pressure is applied to the first inner cavity through the drill rod, the limiting device is restored to the initial state under the action of the pressure, and the steps are repeated to test the next test section.
Compared with the prior art, the invention has the beneficial effects that:
(1) According to the invention, the difference of the water heads inside and outside the drill rod is not required to be considered in the test process, and the waterway in the pressure relief device can be switched by controlling the ascending and descending of the drill rod, so that the purpose of rapidly relieving the pressure of the upper packer and the lower packer is realized;
(2) According to the invention, the drill rod does not need to be lifted repeatedly, the upper valve body can be restored to the initial state by only pressing the drill rod, the test time is greatly saved, and the risk of repeated drilling and tripping is reduced;
(3) Due to the structural characteristics of the upper valve body, the invention can store water in the drill rod during pressure relief, and saves the time required by water discharge and water injection of the drill rod;
(4) The invention fully utilizes the internal pressure of the drill rod to return the piston in the valve body, has simple and practical structure, can improve the testing efficiency and reduces the testing cost.
Drawings
FIG. 1 is a schematic diagram of an initial state of a device for testing the crustal stress by a linkage hydraulic fracturing method according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a structure of a linkage hydraulic fracturing method ground stress testing device according to an embodiment of the present invention when water is injected into a seat to seal upper and lower packers;
FIG. 3 is a schematic diagram of a structure of a linkage hydraulic fracturing method ground stress testing device injecting water into a test section according to an embodiment of the invention;
Fig. 4 is a schematic structural diagram of the linkage hydraulic fracturing method ground stress testing device according to the embodiment of the invention when the device is pulled up to release pressure.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described in the following in conjunction with the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that, in the following embodiments, unless otherwise specified, the experimental methods are conventional methods, and the reagents and materials are commercially available, unless otherwise specified, and in the description of the present invention, the terms "horizontal", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.
The invention will be further illustrated, but is not limited, by the following examples.
As shown in fig. 1, the embodiment of the invention discloses a linkage type hydraulic fracturing method ground stress testing device, which comprises a pressure relief device, an upper packer 5 connected with the pressure relief device through a first pipeline 4 and a lower packer 7 communicated with the upper packer 5 through a second pipeline 6. The pressure relief device comprises an upper valve body, a base 2 and a lower valve body which are sequentially connected. During testing, the upper valve body is connected with the drill rod. In the present embodiment, the upper valve body includes a first housing 100 and a stopper provided in the first housing 100. Specifically, a first inner cavity extending along the axial direction of the first casing 100, a first water outlet hole 101 and a second water outlet hole 102 which are communicated with the first inner cavity are arranged in the first casing 100, and a through hole communicated with the first inner cavity is further arranged at the top of the first casing 100, so that when the drill rod is connected with the upper valve body, the drill rod is communicated with the first inner cavity through the through hole. The first water outlet 101 is an L-shaped water outlet, and is disposed on a side wall of the first inner cavity, and the second water outlet 102 is disposed at a bottom of the side wall of the first inner cavity. The limiting device comprises a first spring 103, an upper valve body piston, a limiting pin 104 and a connecting rope 105, wherein one end of the first spring 103 is connected with the first shell 100, the upper valve body piston is connected with the other end of the first spring 103, the limiting pin 104 is arranged on the side wall of the first inner cavity and used for limiting the upper valve body piston to move, and the connecting rope 105 is connected with the limiting pin 104 at one end and the base 2 at the other end. For the spacer pin return of being convenient for, first inner chamber includes first cavity 106 and the second cavity 107 of being connected with first cavity 106, the internal diameter of first cavity 106 is greater than the internal diameter of second cavity 107, go up the valve body piston and be the T font, it includes first piston body 108 and the second piston body 109 of being connected perpendicularly with first piston body 108, wherein, first piston body 108 adaptation is in first cavity 106, second piston body 109 adaptation is in second cavity 107, go up the valve body piston and remove when first piston body is located first cavity 106 and second cavity 107 junction in first inner chamber, go up the valve body piston unable continuation removal. An L-shaped first passage 110 and a second passage 111 are provided on the upper valve body piston. Wherein, the first channel 110 and the second channel 111 are not communicated with each other, the water inlet end of the first channel 110 is communicated with the first cavity 106, and the water outlet end of the first channel 110 is selectively communicated with the first water outlet 101. One end of the second channel 111 is also selectively communicated with the first water outlet hole 101, the other end of the second channel 111 is communicated with the second cavity 107, and the water inlet end of the second water outlet hole 102 is also communicated with the second cavity 107. in order to limit the upper valve body piston, an L-shaped mounting hole 112 for mounting a limiting pin 104 is formed in the side wall of the first shell 100, a clamping groove 113 is correspondingly formed in the upper valve body piston, when the first piston body 108 is located at the joint of the first cavity 106 and the second cavity 107 in an initial state, the mounting hole 112 is aligned with the clamping groove 113, the limiting pin 104 is inserted into the clamping groove 113 from the mounting hole 112 to fix the upper valve body piston, at the moment, the first spring 103 is in a stretching state, the connecting rope 105 is pulled, the limiting pin 104 is pulled out of the clamping groove 113, and at the moment, the upper valve body piston moves upwards in the first inner cavity to a natural stretching state under the elastic restoring force of the first spring 103. In order to facilitate the return of the limit pin 104 in the initial state, a push-pull device connected with the first spring 103 is further provided on the first housing 100, the push-pull device comprises a bolt 114 with one end penetrating through the top of the first housing 100 and connected with the first spring 103, and a nut 115 connected with the bolt 114 through threads, the nut 115 is screwed, the bolt 114 compresses or stretches the first spring 103, and the position of the clamping groove 113 on the upper valve body piston is regulated and controlled through the first spring 103. When the limiting pin 104 is clamped in the clamping groove 113, the upper valve body piston is limited, at the moment, the first channel 110 is communicated with the first water outlet hole 101, when the pull rope 105 is pulled, the limiting pin 104 is pulled out, and the upper valve body piston is moved towards the bolt direction under the action of the first spring 103 to drive the upper valve body piston to move upwards, so that the first water outlet hole 101 and the second channel 111 are communicated, and the first water outlet hole 101, the second channel 111, the second cavity 107 and the second water outlet hole 102 are sequentially communicated. In order to block the water flow in the first cavity 106 from directly flowing into the first water outlet 101 and to block the water flow between the first channel 110 and the second channel 111, sealing rings 116 are arranged on the inner wall of the first cavity where the first cavity 106 contacts the first piston body 108, on the inner wall of the junction between the second cavity and the first cavity, and on the inner wall of the second cavity above and below the first water outlet 101.
The base 2 is elastically coupled to the first housing 100, and the elastic coupling structure includes a coupling sleeve 200 provided on the bottom surface of the first housing 100, a barrier 201 movably provided inside the coupling sleeve 200, a coupling shaft 202 having one end vertically coupled to the barrier 201 and the other end extending out of the coupling sleeve 200, and a second spring 203 provided to be fitted over the coupling shaft 202 and having one end coupled to the barrier 201 and the other end coupled to the coupling sleeve 200, the coupling shaft 202 being pulled in a direction of the lower valve body 3, the second spring 203 being compressed, and in addition, the other end of the coupling shaft 202 extending out of the coupling sleeve 200 being coupled to the base 2. A third channel 204 is arranged in the base 2, and one end of the third channel 204 is communicated with the first water outlet hole 102 through a third pipeline 205. A connecting rope seat 206 is further arranged on the base 2, one end of the connecting rope 105 is fixed on the limiting pin 104, and the other end of the connecting rope 105 passes through the mounting hole 112 to be fixedly connected with the rope seat 206.
The lower valve body 3 includes a second housing 300 and a lower valve body piston connected to the base 2. A second inner chamber and a fourth water outlet hole 301 are provided in the second housing 200, a central flow passage 302 and a fourth water outlet hole 304 communicating with the central flow passage 302 are provided in the lower valve body piston, the lower valve body piston is movably provided in the second inner chamber, the third water outlet hole 301 communicates with the fourth water outlet hole 304 when the lower valve body piston moves to a limit position in the second inner chamber toward the direction of the base 2, and the third water outlet hole 301 is separated from and does not communicate with the fourth water outlet hole 304 when the lower valve body piston moves to a limit position in the second inner chamber toward the direction away from the base 2. In order to limit the maximum rising distance of the lower valve body piston in the second inner cavity, the lower valve body piston is provided with a limiting structure in a matched mode with the second inner cavity, the limiting structure specifically comprises a third cavity 305 and a fourth cavity 306 connected with the third cavity 305, wherein the inner diameter of the third cavity 305 is smaller than the inner diameter of the fourth cavity 306, the lower valve body piston correspondingly comprises a third piston body 307 and a fourth piston body 308 which are integrally formed, the outer diameter of the third piston body 307 is equal to the inner diameter of the third cavity 305, the outer diameter of the fourth piston body 308 is equal to the inner diameter of the fourth cavity 306, the length of the fourth cavity 306 is larger than the length of the fourth piston body 308, the fourth piston body 308 is matched in the fourth cavity 306, and when the fourth piston body 308 moves to the top of the fourth cavity 306, the lower valve body piston cannot move upwards any more and is limited because the inner diameter of the third cavity 305 is smaller than the outer diameter of the fourth piston body 308, and at the moment, the central flow passage 302, the fourth water outlet 304 and the third water outlet 301 are communicated sequentially. In order to limit the maximum descending distance of the lower valve body piston, a limiting plate 303 is arranged on the third piston body 307, when the limiting plate 303 on which the lower valve body piston descends is propped against the top of the second shell 300, the lower valve body piston descends to the limiting position in the second inner cavity, and at this time, the third water outlet 301 and the fourth water outlet 304 are separated and are not communicated with each other. Two sealing rings 309 are sleeved on the inner wall of the fourth cavity 306 at intervals, the two sealing rings 309 are respectively arranged on the upper side and the lower side of the third water outlet, and the sealing rings are used for blocking water flow in the fourth water outlet 304 from directly flowing into the third water outlet 301 through the fourth cavity 306.
The third water outlet 301 is also communicated with the upper packer 5 through the first pipeline 4, and the upper packer 5 is communicated with the lower packer 7 through the second pipeline 6. In addition, the lower valve body is also connected with the upper packer 5 and the lower packer 7 through the central pipe 8, wherein the fourth cavity 306 is communicated with the central pipe 8, the central pipe 8 penetrates through the upper packer 5 and the lower packer 7 so as to connect the lower valve body, the upper packer and the lower packer, and one end of the central pipe 8 far away from the upper packer 5 is a sealing section. And a test section water outlet 800 for injecting water into the test section is arranged on the central pipeline 8 between the upper packer and the lower packer, when the third water outlet 301 is separated from the fourth water outlet 304 and is not communicated with the fourth water outlet 304, water flow in the central flow channel 302 sequentially flows into the fourth cavity 306 and the central pipeline 8 from the fourth water outlet 304 to pressurize and inject water into the test section.
The embodiment of the invention also provides a testing method of the linkage hydraulic fracturing method ground stress testing device, which comprises the following steps:
Step 1, sequentially connecting a pressure relief device, an upper packer 5 and a lower packer 7 of a testing device, and then connecting the pressure relief device with a drill rod, wherein at the moment, as shown in fig. 1, a first spring 103 in the pressure relief device is in a stretched state, namely a limiting pin 104 is inserted into a clamping groove 113, a first channel 110 on an upper valve body piston is communicated with a first water outlet 101, a lower valve body piston descends to a limit position in a second inner cavity (namely a limiting plate 303 is in contact connection with a second shell 300), and at the moment, a third water outlet 301 is separated from a fourth water outlet 304; then the testing device is lowered to a selected position in the drilling hole through the drill rod, in the lowering process, as shown in fig. 2, under the action of gravity, the second shell 300 is lowered, the lower valve body piston moves to a limit position in the second inner cavity towards the direction of the base 2 (namely, the fourth piston body 308 moves to the top of the fourth cavity 306), at this time, the third water outlet 301 is communicated with the fourth water outlet 304, high-pressure water flow is injected into the drill rod, and flows from the drill rod to the first cavity 106, the first channel 110, the first water outlet 101, the third pipeline 205, the third channel 204, the central runner 302, the fourth water outlet 304, the third water outlet 301, the first pipeline 4, the upper packer 5, the second pipeline 6 and the lower packer 7 in sequence, and the upper packer 5 and the lower packer 7 expand and cling to the drilling hole under the action of the high-pressure water flow, so that a test section is formed between the upper packer and the lower packer;
Step 2, as shown in fig. 3, pressing down the drill rod, moving the lower valve body piston to the limit position in the second inner cavity in the direction away from the base 2, at this time, separating and not communicating the third water outlet 301 with the fourth water outlet 304, enabling high-pressure water in the drill rod to flow into the fourth cavity 306 below the fourth water outlet 304 through the first cavity 106, the first channel 110, the first water outlet 101, the third pipeline 205, the third channel 204, the central flow channel 302 and the fourth water outlet 304, and then flowing into the central pipeline 8 from the fourth cavity 306, and pressurizing and injecting water to the selected test section through the test section water outlet 800 on the central pipeline 8, and testing;
Step 3, after the ground stress test in step 2 is finished, as shown in fig. 4, the drill rod is lifted upwards, the lower valve body piston gradually rises to the limit position in the direction of the base in the second inner cavity in the lifting process, at this time, the third water outlet 301 is communicated with the fourth water outlet 304, the drill rod is continuously lifted, as the upper and lower packers are plugged in the drill hole, the upper valve body moves upwards along with the drill rod, the connecting shaft 202 gradually compresses the second spring 203 to the shortest through the baffle 201, when the second spring 203 cannot be continuously compressed and the upper valve body continuously lifts upwards, the connecting rope 105 is pulled to pull out the limiting pin 104 clamped in the clamping groove 113, the upper valve body piston moves upwards to the first spring 103 in the natural extension state in the first inner cavity under the action of the first spring 103, at this time, the second channel 111 is communicated with the first water outlet 101, the water flow seated in the lower packer 5 and the upper packer 7 sequentially passes through the second pipeline 6, the first pipeline 4, the third water outlet 301, the fourth water outlet 304, the central channel 302, the third pipeline 204, the third water outlet 205, the third water outlet 101 and the second water outlet 107 in turn, and the upper valve body 107 are discharged from the second channel 107 to the upper valve body through the second channel 107;
Fourth, after the pressure and water flow in the upper and lower packers are completely removed, the base 2 and the first casing 100 are restored to the initial state under the action of the second spring 203, the testing device is moved to the next selected testing position by the drill rod, before the test, the pressure is applied to the first inner cavity by the drill rod, the upper valve body piston in the first inner cavity is moved downwards under pressure to the connection position of the first piston body 108 and the second cavity 106, at this time, the clamping groove 113 is aligned with the mounting hole 112, the drill rod is rocked towards the clamping groove 113 to enable the limiting pin 104 to be clamped in the clamping groove 113, the piston in the upper valve body is restored to the initial state, and the test of the next testing section can be completed by repeating the steps.
The foregoing is merely illustrative of the preferred embodiments of the present invention and is not intended to limit the embodiments and scope of the present invention, and it should be appreciated by those skilled in the art that equivalent substitutions and obvious variations may be made using the teachings of the present invention, which are intended to be included within the scope of the present invention.