Hydraulic downhole active positioning system

Abstract

The application discloses a hydraulic downhole active positioning system, and forms a sealed first hydraulic chamber in a positioning pipe section, utilizes external seawater pressure to make a main piston close to a fixed ring, drives a spring clamping component to extend from an opening of the positioning pipe section to realize abutment with a clamping edge structure in the drill collar, and provides a counterforce for a downhole operation tool; hydraulic oil can be introduced into the first hydraulic chamber to resist the pressure of seawater, drive the main piston to be away from the fixed ring, drive the spring clamping component to be retracted into the positioning pipe section, and realize active unhooking of the downhole operation tool in the drill collar, thereby effectively improving the reliability of the downhole positioning system.

Description

Technical Field

[0001] This invention relates to the field of underwater geological in-situ exploration technology, and in particular to a hydraulic downhole active positioning system. Background Technology

[0002] Downhole static cone penetration testing (DCPT) is a method of drilling operations that involves lowering a downhole tool into the drill string of an offshore drilling rig to perform static penetration testing at the bottom of the wellbore. Its main working principle is to lower a cylindrical tool of a certain length from the wellhead to the bottom of the well, fix it in place, and then extend a probe from the tool to perform static penetration testing. The reaction force of the equipment is provided by the downhole positioning system. The downhole positioning system mainly consists of three spring-loaded clamping structures extending from the system structure combined with the drill collar (or drill pipe) structure. The spring-loaded clamping structures hold a special structure in the drill collar, thereby providing the reaction force for the downhole tool. For details on the specific working process of downhole positioning, please refer to existing technology CN111502643A.

[0003] Generally, downhole positioning systems are passive structural devices. During tool retrieval, when the tool's top is subjected to lifting force, the spring-loaded mechanism retracts into the downhole positioning section, thus disengaging the positioning structure from the drill collar and allowing for tool recovery. However, because this structure is passively triggered, its movement is difficult to control directly in the event of unforeseen circumstances. In particular, if the downhole positioning system jams or the spring-loaded mechanism fails to retract, the downhole tool will be unable to disengage from the drill collar, making retrieval impossible. Summary of the Invention

[0004] In view of this, the present invention aims to propose a hydraulic downhole active positioning system, which is intended to solve the problem that downhole working tools cannot be disengaged from the drill collar and improve the reliability of the downhole positioning system.

[0005] The technical solution of this invention is implemented as follows:

[0006] A hydraulic downhole active positioning system includes:

[0007] A positioning tube section is installed inside the drill collar, a central tube passes through the positioning tube section, and multiple openings are provided on the positioning tube section; a retaining structure is provided inside the drill collar;

[0008] A fixing ring is fixedly disposed between the positioning tube section and the central tube. A spring-loaded retaining member is hinged to the fixing ring and can extend from the opening of the positioning tube section to abut against the retaining edge structure of the drill collar. The outer contour of the spring-loaded retaining member forms a dynamic sealing connection with the fixing ring and / or the opening of the positioning tube section.

[0009] A main piston is movably disposed between the positioning tube section and the central tube, and is dynamically sealed to the positioning tube section and the central tube. The main piston is located at one end of the fixed ring, and is connected to the spring-loaded member through a linkage. When the main piston moves away from the fixed ring, it causes the spring-loaded member to retract into the positioning tube section; when the main piston moves closer to the fixed ring, it causes the spring-loaded member to extend out from the opening of the positioning tube section.

[0010] The oil circuit control ring is fixedly disposed between the positioning tube section and the central tube, and the oil circuit control ring is sealed to the positioning tube section and the central tube; a sealed first hydraulic chamber is formed between the main piston and the oil circuit control ring, and the oil circuit control ring is provided with an oil supply line and an oil return line.

[0011] Preferably, the outer peripheral wall of the fixing ring is provided with a plurality of mounting grooves evenly distributed along the circumference;

[0012] The spring clip component is disposed in the mounting groove. The spring clip component is strip-shaped and includes a first end and a second end. A hinge portion is provided between the first end and the second end. The two sides of the hinge portion are hinged to the two inner sidewalls of the mounting groove. The first end is connected to the linkage component so that the first end can extend out from the opening on the positioning tube section to abut against the locking edge structure on the drill collar.

[0013] An elastic element is provided in the first hydraulic chamber or on the oil circuit control ring. The elastic element provides the spring clip member with a force that drives the first end to extend out of the opening on the positioning tube section.

[0014] Preferably, the oil circuit control ring is provided with a second hydraulic chamber, and a movable unloading piston is provided in the second hydraulic chamber. One end of the unloading piston is connected to the second end of the spring clip component through a connecting rod, and the elastic element is provided at the other end of the unloading piston. The chamber in the second hydraulic chamber where the elastic element is located is defined as the rodless chamber, and the other side is defined as the rod chamber. The rodless chamber of the second hydraulic chamber is connected to an unloading pipeline.

[0015] The oil supply line and the unloading line are connected by a first connecting line, and the unloading line and the return line are connected by a second connecting line. The first connecting line is equipped with a first control valve, the second connecting line is equipped with a second control valve, and the return line is equipped with a third control valve. The second connecting line is connected to the return line after the third control valve.

[0016] Preferably, it further includes a pressure measuring device for detecting the pressure in the rodless chamber of the second hydraulic chamber, and when the pressure value detected by the pressure measuring device is greater than a set value, the first control valve opens.

[0017] Preferably, the first control valve is provided with an overflow structure.

[0018] Preferably, the first control valve, the second control valve, and the third control valve are all electromagnetic control valves.

[0019] Preferably, the elastic element is a spring.

[0020] Preferably, the mounting groove is provided with a sealing positioning plate located on the side of the hinge portion away from the axis of the fixing ring. The outer side of the hinge portion of the spring clip member has a first arc-shaped abutment portion that seals against the sealing positioning plate. The two sides of the spring clip member seal against the two inner sidewalls of the mounting groove. The first end of the spring clip member has a second arc-shaped abutment portion that seals against the edge of the opening of the positioning tube section. Both the first arc-shaped abutment portion and the second arc-shaped abutment portion are arc surfaces centered on the rotation axis of the hinge portion.

[0021] Preferably, the sealing positioning plate is in surface contact with the first arc-shaped abutment portion, and the edge of the opening is in surface contact with the second arc-shaped abutment portion.

[0022] Preferably, the linkage is an L-shaped crank component, one end of which is hinged to the main piston and the other end is hinged to the side of the first end near the center of the fixed ring.

[0023] Compared to existing technologies, the hydraulic downhole active positioning system of the present invention forms a sealed first hydraulic chamber within the positioning section. External seawater pressure is used to bring the main piston closer to the fixed ring, driving the spring-loaded component to extend from the opening of the positioning section and engage with the locking structure within the drill collar, providing a reaction force for the downhole tool. Hydraulic oil can be introduced into the first hydraulic chamber to resist seawater pressure, driving the main piston away from the fixed ring and causing the spring-loaded component to retract into the positioning section. This enables the downhole tool to actively disengage within the drill collar, effectively improving the reliability of the downhole positioning system.

[0024] Furthermore, the beneficial effects of other alternative solutions in this application are further described / demonstrated in specific embodiments. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of a hydraulic downhole active positioning system according to the present invention;

[0027] Figure 2 This is a side view schematic diagram of a hydraulic downhole active positioning system according to the present invention;

[0028] Figure 3 for Figure 2 A cross-sectional view of AA (the state of the spring clip component abutting against the clip edge structure);

[0029] Figure 4 for Figure 2 A cross-sectional view of the middle AA (the state where the spring clip component is separated from the clip edge structure);

[0030] Figure 5 This is a front view schematic diagram of a hydraulic downhole active positioning system according to the present invention;

[0031] Figure 6 for Figure 4 Cross-sectional view of BB;

[0032] Figure 7 This is an exploded schematic diagram of the fixing ring and the spring clip component;

[0033] Figure 8 This is an enlarged cross-sectional view of the spring clip component engaging with the fixing ring and positioning tube section;

[0034] Figure 9 This is a hydraulic schematic diagram of a hydraulic downhole active positioning system according to the present invention.

[0035] In the diagram: 100, drill collar; 110, clamping structure; 200, hydraulic system;

[0036] 1. Positioning pipe section; 11. Opening; 12. Central pipe; 13. First hydraulic chamber;

[0037] 2. Retaining ring; 21. Mounting groove; 22. Sealing positioning plate;

[0038] 3. Spring-loaded component; 31. First end; 311. Second arc-shaped abutment part; 32. Second end; 33. Hinge part; 331. First arc-shaped abutment part;

[0039] 4. Main piston; 41. Linkage component;

[0040] 5. Oil circuit control ring; 51. Oil supply line; 52. Oil return line; 521. Third control valve; 53. Second hydraulic chamber; 54. Unloading piston; 55. Unloading line; 56. First connecting line; 561. First control valve; 57. Second connecting line; 571. Second control valve; 58. Pressure measuring device;

[0041] 6. Elastic components;

[0042] 7. Connecting rod. Detailed Implementation

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and 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. Therefore, they should not be construed as limitations on this invention.

[0045] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0046] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0047] refer to Figure 1-9 This paper illustrates a hydraulic downhole active positioning system, including a positioning pipe section 1, a fixing ring 2, a main piston 4, and an oil circuit control ring 5.

[0048] The positioning tube section 1 is disposed inside the drill collar 100, and a central tube 12 passes through the positioning tube section 1. The positioning tube section 1 has multiple openings 11; the drill collar 100 has a retaining structure 110 inside.

[0049] The fixing ring 2 is fixedly disposed between the positioning tube section 1 and the central tube 12. A spring-loaded retaining member 3 is hinged to the fixing ring 2, which can extend out from the opening 11 of the positioning tube section 1 to abut against the retaining edge structure 110 of the drill collar 100. The outer contour of the spring-loaded retaining member 3 forms a dynamic sealing connection with the fixing ring 2 and / or the opening 11 of the positioning tube section 1.

[0050] The main piston 4 is movably disposed between the positioning tube section 1 and the central tube 12, and the main piston 4 is dynamically sealed to the positioning tube section 1 and the central tube 12; the main piston 4 is located at one end of the fixed ring 2, and the main piston 4 is connected to the spring-loaded member 3 through the linkage 41; when the main piston 4 moves away from the fixed ring 2, it causes the spring-loaded member 3 to retract into the positioning tube section 1; when the main piston 4 moves closer to the fixed ring 2, it causes the spring-loaded member 3 to extend out from the opening 11 of the positioning tube section 1.

[0051] The oil circuit control ring 5 is fixedly disposed between the positioning tube section 1 and the central tube 12, and the oil circuit control ring 5 is sealed to the positioning tube section 1 and the central tube 12; the main piston 4 and the oil circuit control ring 5 form a sealed first hydraulic chamber 13, and the oil circuit control ring 5 is provided with an oil supply line 51 and an oil return line 52.

[0052] Specifically, the first hydraulic chamber 13 is formed through the seals between the main piston 4 and the positioning tube section 1, the seals between the spring clip member 3 and the fixing ring 2 and / or the positioning tube section 1, and the seals between the oil circuit control ring 5. Thus, the first hydraulic chamber 13 and the external seawater are located on opposite sides of the main piston 4, forming a hydraulic cylinder structure. (Reference) Figure 3 , Figure 4 and Figure 9 , Figure 9The large hydraulic cylinder includes a rod chamber and a rodless chamber. The first hydraulic chamber 13 serves as the rod chamber, while the rodless chamber is pressurized by external seawater. According to existing technology (e.g., CN111502643A), during use, the main piston 4 is positioned above the fixed ring 2. Initially, under the pressure of the seawater, the main piston 4 is close to the fixed ring 2 (in this embodiment, the main piston 4 is pressed tightly against the fixed ring 2). This allows the main piston 4 to push the spring-loaded member 3 out of the opening 11 via the linkage 41. The spring-loaded member 3 can then abut against the locking edge structure 110 of the drill collar 100 (in this state, as shown). Figure 3 As shown), this provides a reaction force for downhole working tools. When it is necessary to actively retract the spring-loaded component 3 into the positioning section 1, hydraulic oil is supplied to the first hydraulic chamber 13 to resist the pressure of seawater, driving the main piston 4 away from the fixed ring 2, and causing the spring-loaded component 3 to retract into the positioning section 1 (the state at this time is as shown). Figure 4 As shown, this enables downhole tools to actively detach within the drill collar 100, effectively improving the reliability of the downhole positioning system.

[0053] As can be seen from existing technologies (e.g., CN111502643A), downhole working tools include a positioning system and a probe installed in the drill collar 100. The downhole working tools also include a hydraulic system 200. Conventionally, when the positioning system and the drill collar 100 cooperate to provide reaction force, the hydraulic system 200 drives the probe to drill into the seabed to achieve static penetration testing. In this invention, the central tube 12 can be threaded with a composite cable (not shown), which can supply oil and / or electricity. The hydraulic downhole active positioning system of this invention can share a hydraulic system 200 with the downhole working tools.

[0054] It should also be noted that the type of hydraulic oil supplied to the first hydraulic chamber 13 in the hydraulic system 200 is not limited; it can be silicone oil or even water.

[0055] In some embodiments, reference Figure 4-7The outer peripheral wall of the fixing ring 2 is provided with a plurality of mounting grooves 21 distributed equidistantly along the circumference. In this embodiment, there are 3 mounting grooves 21, but the number can be set to more. The spring-loaded member 3 is disposed in the mounting groove 21. The spring-loaded member 3 is strip-shaped and includes a first end 31 and a second end 32. A hinge portion 33 is provided between the first end 31 and the second end 32. The two sides of the hinge portion 33 are hinged to the two inner sidewalls of the mounting groove 21. The first end 31 is connected to the linkage member 41 so that the first end 31 can extend from the opening 11 on the positioning tube section 1 to abut against the retaining edge structure 110 on the drill collar 100. An elastic member 6 is provided in the first hydraulic chamber 13 or on the oil circuit control ring 5. The elastic member 6 provides the spring-loaded member 3 with a force to drive the first end 31 to extend from the opening 11 on the positioning tube section 1.

[0056] In this embodiment, external seawater and the elastic element 6 act simultaneously on the spring-loaded member 3, ensuring that the spring-loaded member 3 stably extends from the opening 11. Preferably, the seawater acts on the first end 31 of the spring-loaded member 3 through the main piston 4 and the linkage 41, and the elastic element 6 acts on the second end 32 of the spring-loaded member 3. The elastic element 6 can be a spring, a spring, or other elastic structure. During the process of actively driving the spring-loaded member 3 to retract into the positioning tube section 1, hydraulic oil is supplied to the first hydraulic chamber 13, driving the main piston 4 away from the fixed ring 2. The main piston 4 drives the first end 31 to retract through the linkage 41. During this process, the spring-loaded member 3 rotates around the hinge portion 33, and the second end 32 overcomes the elastic force of the elastic element 6.

[0057] For specific details, please refer to Figure 8 The linkage 41 is an L-shaped crank component, one end of which is hinged to the main piston 4, and the other end is hinged to the side of the first end 31 near the axis of the fixed ring 2.

[0058] In some embodiments, reference Figure 3 , Figure 9The oil circuit control ring 5 is provided with a second hydraulic chamber 53, and a movable unloading piston 54 is provided in the second hydraulic chamber 53. One end of the unloading piston 54 is connected to the second end 32 of the spring clip component 3 through a connecting rod 7, and the elastic element 6 is provided at the other end of the unloading piston 54. The chamber in the second hydraulic chamber 53 where the elastic element 6 is located is defined as the rodless chamber, and the other side is defined as the rod chamber. The rodless chamber of the second hydraulic chamber 53 is connected to the unloading pipeline 55. The oil supply pipeline 51 and the unloading pipeline 55 are connected through a first connecting pipeline 56, and the unloading pipeline 55 and the return oil pipeline 52 are connected through a second connecting pipeline 57. The first connecting pipeline 56 is provided with a first control valve 561, the second connecting pipeline 57 is provided with a second control valve 571, and the return oil pipeline 52 is provided with a third control valve 521. The second connecting pipeline 57 is connected to the return oil pipeline 52 after the third control valve 521.

[0059] In this embodiment, reference Figure 9 The first hydraulic chamber 13 is equivalent to Figure 9 The rod chamber of the medium and large cylinder block, the second hydraulic chamber 53 is equivalent to Figure 9 The entire cylinder body of the small and medium-sized cylinder body, the rod chamber of the second hydraulic chamber 53 is connected to the first hydraulic chamber 13;

[0060] Specifically, in this embodiment, in the initial state, the spring-loaded member 3 extends out from the opening 11;

[0061] When the spring clip component 3 is retracted, the first control valve 561 and the second control valve 571 are closed, the second control valve 571 is opened, the hydraulic system 200 oil pump is started, the pressure in the first hydraulic chamber 13 increases, the main piston 4 moves upward, the unloading piston 54 moves downward, so that the spring clip component 3 is retracted into the positioning tube section 1.

[0062] When the spring clip component 3 is reset (reset to its initial state), the hydraulic system 200 oil pump does not need to be started, the second control valve 571 is closed, and the first control valve 561 and the third control valve 521 are open. Under the pressure of external seawater (such as...), Figure 9In the rodless chamber of the large cylinder, the main piston 4 moves downward, and the unloading piston 54 moves upward in conjunction. The hydraulic oil in the first hydraulic chamber 13 mainly flows back to the main oil tank of the hydraulic system 200 through the return oil line 52. Some hydraulic oil enters the rodless chamber of the second hydraulic chamber 53, allowing the spring-loaded member 3 to extend from the opening 11. Then, the first control valve 561 and the third control valve 521 are closed, so that the rodless chamber of the second hydraulic chamber 53 is sealed. The space of the rodless chamber of the second hydraulic chamber 53 is not reduced, so that the spring-loaded member 3 will not be accidentally retracted into the positioning tube section 1, improving the stability of the state in which the spring-loaded member 3 extends from the opening 11.

[0063] Preferred, Reference Figure 7 and Figure 9 It also includes a pressure measuring device 58 for detecting the pressure in the rodless chamber of the second hydraulic chamber 53. When the pressure value detected by the pressure measuring device 58 is greater than a set value, the first control valve 561 opens.

[0064] Specifically, when the spring-loaded component 3 abuts against the clamping structure 110 of the drill collar 100, it bears the reaction force generated during the seabed penetration operation. The pressure borne by the spring-loaded component 3 is transmitted to the unloading piston 54 through the connecting rod 7. The unloading piston 54 compresses the hydraulic oil in the rodless chamber of the second hydraulic chamber 53. The pressure of the hydraulic oil in the rodless chamber of the second hydraulic chamber 53 can be measured by the pressure measuring device 58 to calculate the pressure borne by the spring-loaded component 3 for monitoring the load. When an abnormal situation occurs, that is, the pressure value detected by the pressure measuring device 58 is greater than the set value, the first control valve 561 can be opened. Under the load borne by the spring-loaded component 3, the unloading piston 54 moves downward, and the hydraulic oil in the rodless chamber of the second hydraulic chamber 53 is forced into the first hydraulic chamber 13, causing the main piston 4 to move upward. The spring-loaded component 3 is then retracted into the positioning tube section 1, thereby achieving overload protection and preventing damage to the structure of the hydraulic downhole active positioning system.

[0065] It should be noted that when the pressure value detected by the pressure measuring device 58 is within a safe range, the hydraulic oil in the rodless chamber of the second hydraulic chamber 53 can ensure that the spring clip component 3 will not be accidentally drawn into the positioning tube section 1.

[0066] Preferably, the first control valve 561 is equipped with an overflow structure. When a control malfunction prevents the first control valve 561 from being manually opened, the overflow structure can automatically open the first control valve 561 when the rodless chamber pressure in the second hydraulic chamber 53 is overloaded, ensuring that the spring-loaded component 3 can still operate effectively without power. It should be noted that the overflow structure is existing technology in the field of control valves, so it will not be described in detail here. Optionally, the first control valve 561, the second control valve 571, and the third control valve 521 are all electromagnetic control valves, which facilitates remote operation.

[0067] In some embodiments, to facilitate a dynamic sealing connection between the outer contour of the spring clip member 3 and the opening 11 of the fixing ring 2 and / or the positioning tube section 1, thereby ensuring that the first hydraulic chamber 13 remains sealed during the movement of the spring clip member 3; Reference Figure 3-8 The mounting groove 21 is provided with a sealing positioning plate 2 located on the side of the hinge portion 33 away from the axis of the fixing ring 2. The outer side of the hinge portion 33 of the spring clip member 3 forms a first arc-shaped abutment portion 331 that seals against the sealing positioning plate 2. The two sides of the spring clip member 3 seal against the two inner sidewalls of the mounting groove 21. The first end 31 of the spring clip member 3 forms a second arc-shaped abutment portion 311 that seals against the edge of the opening 11 of the positioning tube section 1. Both the first arc-shaped abutment portion 331 and the second arc-shaped abutment portion 311 are arc surfaces with the rotation axis of the hinge portion 33 as the center.

[0068] Thus, when the spring-loaded component 3 moves, it rotates around the axis of the hinge portion 33. The first arc-shaped abutment portion 331 maintains a sealed abutment with the sealing positioning plate 2, the two sides of the spring-loaded component 3 maintain a sealed abutment with the two inner sidewalls of the mounting groove 21, and the second arc-shaped abutment portion 311 maintains a sealed abutment with the edge of the opening 11. That is, after the spring-loaded component 3 is retracted into the positioning tube section 1, the first end 31 of the spring-loaded component 3 still maintains a sealed contact with the edge of the opening 11. Figure 4 As shown.

[0069] In this design, the first arc-shaped abutment portion 331 and the sealing positioning plate 2, and the second arc-shaped abutment portion 311 and the edge of the opening 11, can be in line contact; however, to ensure a sealing effect, the sealing positioning plate 2 and the first arc-shaped abutment portion 331 are in surface contact, and the edge of the opening 11 and the second arc-shaped abutment portion 311 are in surface contact. That is, the sealing positioning plate 2 has an outer surface contour adapted to the first arc-shaped abutment portion 331, and the edge of the opening 11 has an outer surface contour adapted to the second arc-shaped abutment portion 311.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hydraulic downhole active positioning system, characterized in that, include: A positioning tube section is installed inside the drill collar, a central tube passes through the positioning tube section, and multiple openings are provided on the positioning tube section; a retaining structure is provided inside the drill collar; A fixing ring is fixedly disposed between the positioning tube section and the central tube. A spring-loaded retaining member is hinged to the fixing ring and can extend from the opening of the positioning tube section to abut against the retaining edge structure of the drill collar. The outer contour of the spring-loaded retaining member forms a dynamic sealing connection with the fixing ring and / or the opening of the positioning tube section. A main piston is movably disposed between the positioning tube section and the central tube, and is dynamically sealed to the positioning tube section and the central tube. The main piston is located at one end of the fixed ring, and is connected to the spring-loaded member through a linkage. When the main piston moves away from the fixed ring, it causes the spring-loaded member to retract into the positioning tube section; when the main piston moves closer to the fixed ring, it causes the spring-loaded member to extend out from the opening of the positioning tube section. An oil circuit control ring is fixedly disposed between the positioning tube section and the central tube, and the oil circuit control ring is sealed to the positioning tube section and the central tube; a sealed first hydraulic chamber is formed between the main piston and the oil circuit control ring, and the oil circuit control ring is provided with an oil supply line and an oil return line; The outer peripheral wall of the fixing ring is provided with multiple mounting grooves that are equidistantly distributed along the circumference. The spring clip component is disposed in the mounting groove. The spring clip component is strip-shaped and includes a first end and a second end. A hinge portion is provided between the first end and the second end. The two sides of the hinge portion are hinged to the two inner sidewalls of the mounting groove. The first end is connected to the linkage component so that the first end can extend out from the opening on the positioning tube section to abut against the locking edge structure on the drill collar. An elastic element is provided in the first hydraulic chamber or on the oil circuit control ring, and the elastic element provides the spring clip component with a force to drive the first end to extend out of the opening on the positioning tube section; The oil circuit control ring is provided with a second hydraulic chamber, and a movable unloading piston is provided in the second hydraulic chamber. One end of the unloading piston is connected to the second end of the spring clip component through a connecting rod, and the elastic element is provided at the other end of the unloading piston. The chamber in the second hydraulic chamber where the elastic element is located is defined as the rodless chamber, and the other side is defined as the rod chamber. The rodless chamber of the second hydraulic chamber is connected to an unloading pipeline. The oil supply line and the unloading line are connected by a first connecting line, and the unloading line and the return line are connected by a second connecting line. The first connecting line is equipped with a first control valve, the second connecting line is equipped with a second control valve, and the return line is equipped with a third control valve. The second connecting line is connected to the return line after the third control valve.

2. The hydraulic downhole active positioning system according to claim 1, characterized in that, It also includes a pressure measuring device for detecting the pressure inside the rodless chamber of the second hydraulic chamber. When the pressure value detected by the pressure measuring device is greater than a set value, the first control valve opens.

3. The hydraulic downhole active positioning system according to claim 2, characterized in that, The first control valve is equipped with an overflow structure.

4. The hydraulic downhole active positioning system according to any one of claims 1-3, characterized in that, The first control valve, the second control valve, and the third control valve are all electromagnetic control valves.

5. The hydraulic downhole active positioning system according to claim 1, characterized in that, The elastic element is a spring.

6. The hydraulic downhole active positioning system according to claim 1, characterized in that, The mounting groove is provided with a sealing positioning plate located on the side of the hinge portion away from the axis of the fixing ring. The outer side of the hinge portion of the spring clip member has a first arc-shaped abutment portion that seals against the sealing positioning plate. The two sides of the spring clip member seal against the two inner sidewalls of the mounting groove. The first end of the spring clip member has a second arc-shaped abutment portion that seals against the edge of the opening of the positioning tube section. Both the first arc-shaped abutment portion and the second arc-shaped abutment portion are arc surfaces with the rotation axis of the hinge portion as the center.

7. The hydraulic downhole active positioning system according to claim 6, characterized in that, The sealing positioning plate is in surface contact with the first arc-shaped abutment part, and the edge of the opening is in surface contact with the second arc-shaped abutment part.

8. The hydraulic downhole active positioning system according to claim 1, characterized in that, The linkage is an L-shaped crank component, one end of which is hinged to the main piston, and the other end is hinged to the side of the first end near the center of the fixed ring.

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