An active pressure-yielding anti-shale creep wellbore structure and its control method

Abstract

The present invention discloses an active pressure-yielding wellbore structure for resisting shale creep and its control method, comprising: multiple sets of casing components, coaxially connected up and down by supports, each set of casing components comprising an inner casing and an outer casing; a support provided between the inner casing and the outer casing, the support being capable of exerting force on the inner wall of the outer casing; a strain sensing component arranged on the outer circumference of the outer casing and connected to a controller; wherein, when the strain sensing component senses that the extrusion force exerted on the outer casing by shale creep deformation is greater than a certain value, the controller controls the support to move a certain distance toward the center of the casing component after receiving the strain signal, and maintains the support exerting force on the inner wall of the outer casing. The present invention achieves active pressure-yielding of shale creep deformation in the wellbore by applying force to the inner wall of the outer casing, and the controller controls the support to move and maintain the force-applying state. This can continuously resist minor creep deformation and avoid rapid destruction of the wellbore casing components after compressive yielding.

Description

Technical Field

[0001] The present invention relates to the field of oil and gas exploitation, and in particular to an active pressure-yielding anti-shale creep wellbore structure and a control method thereof. Background Art

[0002] Shale reservoirs refer to the pores and fractures within mudstone containing shale oil or shale gas, such as shale gas that exists in an adsorbed or free state within mudstone and its interlayers. These pores and fractures are the main spaces for oil and gas storage and flow, and generally have low porosity and low permeability.

[0003] During shale gas extraction, reservoir fracturing is performed by artificially creating cracks in the formation, thereby improving the flow environment of shale gas in the reservoir and providing efficient migration channels. This modification technology can effectively increase the effective area of ​​the reservoir, improve its permeability, make underground oil more easily recoverable, and thus increase oil well production. The use of methane in-situ explosion fracturing technology has attracted much attention. This technology uses methane desorbed from the shale reservoir as the combustible material and, by introducing a suitable combustion aid, achieves a precise in-situ explosion process in the well.

[0004] Methane explosion will generate intense high temperature and high pressure, thus forming a complex fracture network system inside the reservoir. In the early stage of fracturing, the wellbore shale may still be stable, but over time, the deformation of the shale gas wellbore will continue to extend under the action of creep, and the ground stress will gradually transfer to the wellbore casing, eventually leading to the collapse and instability of the shale gas wellbore. Especially in the development of deep resources, the creep deformation of the wellbore shale is significant under the high ground temperature and high ground stress at a depth of 2000m. This creep deformation is different from the elastic-plastic deformation of the rock. It involves the viscoelastic-plastic deformation of the rock. It is reflected in the strain nature and manifests as a slow increase in time-based strain, such as the slow shrinkage of the open hole wellbore. In order to slow down this slow collapse deformation, it is necessary to continuously provide a certain pressure support to the inner wall of the wellbore. Conventional metal casing is a brittle material and does not have the ability to withstand continuous pressure. Summary of the Invention

[0005] The purpose of the present invention is to provide an active pressure-yielding anti-shale creep wellbore structure, which can achieve active pressure relief for wellbore shale creep deformation, continuously resist small creep deformation, and avoid rapid destruction of wellbore casing components after compressive yielding.

[0006] To achieve the above-mentioned purpose, the present invention provides an active pressure-yielding anti-shale creep wellbore structure, comprising:

[0007] Multiple sets of sleeve components are coaxially connected up and down through a support member, and each set of sleeve components has an inner sleeve and an outer sleeve;

[0008] A support is provided between the inner sleeve and the outer sleeve, and the support can exert force on the inner wall of the outer sleeve;

[0009] A strain sensing element is arranged on the outer peripheral side of the outer sleeve and connected to the controller;

[0010] Among them, when the strain sensing component senses that the squeezing force of shale creep deformation on the outer casing is greater than a certain value, the controller controls the support to move a certain distance toward the center of the casing component after receiving the strain signal, and keeps the support exerting force on the inner wall of the outer casing.

[0011] In some examples of the present invention, the outer sleeve includes a plurality of curved plates;

[0012] A plurality of arc-shaped plates are arranged circumferentially, and adjacent circumferential plates are movably connected via a first hinge to form a circular ring structure;

[0013] Each curved plate is provided with a strain sensing component, and the supports can exert force on the curved plates respectively.

[0014] In some examples of the present invention, a plurality of arc-shaped plates are first arranged circumferentially and then arranged vertically, and the upper and lower adjacent arc-shaped plates are movably connected via a second hinge.

[0015] In some examples of the present invention, the support comprises:

[0016] Filler, filled between the outer sleeve and the inner sleeve;

[0017] A plurality of elastic members are installed on the inner side of the corresponding arc-shaped plates. Each elastic member has a hydraulic cylinder. The output end of the hydraulic cylinder acts on the inner side of the arc-shaped plate, and the oil path passes through between the outer sleeve and the inner sleeve.

[0018] In some examples of the present invention, the output end of the hydraulic cylinder acts on the inner side of the curved plate through a top pressure plate;

[0019] The elastic member also includes a spring, which is compressed and located between the arc plate and the inner sleeve.

[0020] In some examples of the present invention, the elastic modulus E of the spring is calculated as follows:

[0021] E=POS / k

[0022] Where S is the outer surface area of ​​the curved plate, m 2 ; k is the stroke of the hydraulic cylinder, m; P0 is the maximum compressive strength of the curved plate, MPa.

[0023] In some examples of the present invention, positioning rings are fixed to the outer sides of the adjacent outer sleeves;

[0024] The supporting member is provided with external threads on its circumference;

[0025] The cross section of the locking sleeve is an L-shaped ring structure, one side of which presses on the positioning ring and the inner side is threadedly connected to the external thread of the support member so that the outer sleeve is connected to the support member.

[0026] In some examples of the present invention, the support member is composed of a first ring member, a second ring member, and a third ring member coaxially arranged from outside to inside;

[0027] The middle parts of the first ring member, the second ring member and the third ring member are connected by a partition plate to form a first annular groove and a second annular groove that are adjacently and symmetrically arranged;

[0028] The outer sleeve is located in the first annular groove, and the inner sleeve is embedded in the second annular groove; the partition is provided with through holes that connect adjacent first annular grooves to each other, and through holes that connect adjacent inner sleeves to each other.

[0029] The present invention also aims to provide a control method for a wellbore structure that actively yields pressure to resist shale creep. By applying force to the inner wall of the outer casing through a support, and a controller controlling the movement of the support and maintaining the force application state, active yielding of the wellbore shale creep deformation is achieved, which can continuously resist small creep deformation and avoid rapid destruction of the wellbore casing components after compressive yielding.

[0030] A method for controlling an active pressure-yielding anti-shale creep wellbore structure comprises the following steps:

[0031] S1, placing multiple sets of casing components in a borehole or wellbore. When the casing components are at a deeper position or a three-dimensional fracture network is established by methane explosion, the controller controls the hydraulic cylinder to act on the inner side of the curved plate, so that the curved plate can withstand an external extrusion force of 0.5 MPa without deformation;

[0032] S2, based on time, the creep deformation of the wellbore shale will squeeze the outer casing;

[0033] Each curved plate circumferentially matches the creep deformation of shale at different locations in the wellbore and can be adjusted in real time through movable connections. The strain sensors on the curved plates sense the squeezing force of the external shale creep deformation on the outer casing.

[0034] S3: When the creep extrusion pressure of the wellbore shale exceeds 0MPa, the controller controls the hydraulic cylinder to retract toward the center of the casing component, ensuring that the curved plate has a certain compressive resistance during the retraction process. After the retraction is completed, the strain sensing element senses the external shale strain and the extrusion pressure on the outer casing decreases. The controller then controls the hydraulic cylinder to act on the inner side of the curved plate, ensuring that the curved plate can still withstand the extrusion pressure of 0MPa.

[0035] S4, when the creep extrusion pressure of the shale is greater than P0MPa again, the hydraulic cylinder then retracts a certain distance and then applies force to the inner side of the curved plate, and keeps the curved plate able to withstand the external extrusion pressure of P0MPa, repeating step S3 until the controller hydraulic cylinder retracts to the limit position.

[0036] Compared with existing technologies, this active pressure-yielding wellbore structure for resisting shale creep uses coaxially arranged inner and outer casings with supports interposed between them. The supports exert force on the inner wall of the outer casing, and a controller controls the movement of the supports and maintains the force-applying state, thereby achieving active pressure-yielding against shale creep deformation in the wellbore. This can continuously resist minor creep deformation and avoid rapid destruction of the wellbore casing components after compressive yielding.

[0037] Because the outer casing includes multiple curved plates, on the one hand, the multiple curved plates are movable through the first hinge to form a circular ring structure, which can actively release pressure in response to shale creep deformation on the circumferential side. On the other hand, the multiple curved plates are axially movably connected through the second hinge, which can actively release pressure in response to shale creep deformation on the axial side. This achieves separate pressure release of the outer casing on the axial and circumferential sides, avoiding mutual influence and being more targeted.

[0038] Since the support member is divided into a symmetrical structure by a partition, it can be connected to adjacent sleeve components, so that the interiors of adjacent inner sleeves are interconnected and adjacent first ring bodies are interconnected. This not only realizes the interconnection of multiple groups of sleeve components, but also allows the controlled wires or oil circuits in the support to be led out, making it convenient for control. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the sleeve component in the present invention;

[0040] Figure 2 is a cross-sectional view of the outer sleeve and the inner sleeve in the present invention;

[0041] Figure 3 This is a front view of the outer sleeve of the present invention, which is assembled with multiple arc-shaped plates connected vertically;

[0042] Figure 4 It is a front view of the assembly between adjacent sleeve components in the present invention;

[0043] Figure 5 is a schematic diagram of a support member in the present invention;

[0044] In the figure: 10, outer sleeve, 11, curved plate, 12, first hinge, 13, second hinge;

[0045] 20. Inner casing;

[0046] 30. Support member, 31. First ring member, 32. Second ring member, 33. Third ring member, 34. First annular groove, 35. Second annular groove, 36. Partition plate, 37. Through hole;

[0047] 40. Locking sleeve;

[0048] 50. Positioning ring;

[0049] 60. Support, 61. Hydraulic cylinder, 62. Top pressure plate, 63. Filler, 64. Spring;

[0050] 70. Strain sensing parts. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the technical solution of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of specific embodiments of the present invention. The same figure marks in the drawings represent the same parts. It should be noted that the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by persons of ordinary skill in the field to which the invention belongs. The words "first", "second" and similar terms used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "a" or "an" do not necessarily indicate a quantity limitation. Words such as "include" or "comprising" mean that the components or objects appearing before the word include the components or objects listed after the word and their equivalents, without excluding other components or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0053] like Figures 1 to 3 As shown, the present invention is an active pressure-yielding anti-shale creep wellbore structure, comprising:

[0054] Multiple sets of sleeve components are coaxially connected up and down through a support member 30, and each set of sleeve components has an inner sleeve 20 and an outer sleeve 10;

[0055] A support 60 is provided between the inner sleeve 20 and the outer sleeve 10, and the support 60 can exert force on the inner wall of the outer sleeve 10;

[0056] The strain sensing element 70 is arranged on the outer peripheral side of the outer sleeve 10 and connected to the controller;

[0057] After receiving the strain signal, the controller controls the support 60 to move a certain distance toward the center of the sleeve component and keeps the support 60 exerting force on the inner wall of the outer sleeve 10.

[0058] Specifically, multiple sets of casing components are located in a borehole or wellbore, and multiple fracturing holes may be provided on the casing components according to the requirements for reservoir fracturing and the pre-formed three-dimensional fracture network;

[0059] The inner casing 20 and the outer casing 10 are coaxially connected and form an annular cavity therebetween. A support 60 is provided in the annular cavity. As explained, a rib plate may be provided between the inner casing 20 and the outer casing 10 for connection and fixation. The strain sensing element 70 may be a strain gauge. Multiple strain gauges are located on the outside of the outer casing 10 and are configured to sense the squeezing force of the outer casing 10 caused by the external shale strain.

[0060] The controller can be the control center of the wellbore explosion. After receiving the strain signals from multiple strain gauges, it controls the movement of the support 60. This movement can slow down or offset the squeezing force of the external shale on the outer casing 10, preventing the outer casing 10 from deforming too much and reducing the compressive effect on the creep deformation of the shale.

[0061] Before use, this active yielding type anti-shale creep wellbore structure is placed in a borehole / wellbore according to a reservoir fracturing and transformation plan. Adjacent casing components can be connected by a support member 30 to meet a certain length of the wellbore. The casing components can be appropriately filled with cement sheaths. At the locations where reservoir fracturing and three-dimensional fracture networks are required, methane gas and combustion-supporting agent in-situ coordinated detonation equipment is installed and sealed.

[0062] After the methane explosion is complete, the high-temperature, high-pressure gas penetrates the fracturing holes and impacts the reservoir, creating a three-dimensional fracture network. The high-temperature, high-pressure impact will damage the shale in the wellbore, weakening the strength and stiffness of the shale. Under the action of creep over a long period of time, the ground stress is gradually transferred to the casing components of the wellbore.

[0063] Initially, the controller controls the support 60 to exert force on the inner wall of the outer casing 10, allowing the outer casing 10 to withstand an external extrusion pressure of 0MPa without deformation. After a certain period of time, the creep deformation of the wellbore shale will squeeze the outer casing 10. When the creep extrusion pressure of the wellbore shale sensed by the strain gauge is greater than 0MPa, it means that the outer casing 10 will deform. At this time, the controller controls the support 60 to move a certain distance toward the center of the casing component to actively release the pressure. After the movement is completed, the support 60 still exerts force on the outer casing 10, allowing the outer casing 10 to recover and withstand the external extrusion pressure of 0MPa.

[0064] This active pressure-yielding wellbore structure for resisting shale creep adopts a coaxially arranged inner casing 20 and outer casing 10, with a support 60 provided therebetween. The support 60 applies force to the inner wall of the outer casing 10, and a controller controls the movement of the support 60 and maintains the force-applying state, thereby achieving active pressure-yielding of shale creep deformation in the wellbore. It can continuously resist minor creep deformation and avoid rapid destruction of the wellbore casing components after compressive yielding.

[0065] In some examples of the present invention, Figure 2 、 Figure 3 As shown, the outer sleeve 10 includes a plurality of arc-shaped plates 11;

[0066] A plurality of arc-shaped plates 11 are arranged circumferentially, and adjacent circumferential plates are movably connected by first hinges 12 to form a circular ring structure;

[0067] Each curved plate 11 is provided with a strain sensing member 70 , and the support 10 can exert force on the curved plate 11 respectively;

[0068] In some examples of the present invention, the plurality of arc-shaped plates 11 are first arranged circumferentially and then arranged vertically, and the upper and lower adjacent arc-shaped plates 11 are movably connected via the second hinge 13;

[0069] Specifically, the curved plate 11 is made of non-brittle material, such as a tile-shaped steel structure, which can withstand a certain degree of extrusion deformation; the inner casing 20 is a steel screen pipe;

[0070] When the casing is located in a deeper wellbore or a three-dimensional fracture network is established by methane explosion, the time-dependent creep deformation of the wellbore shale will squeeze the outer casing 10, causing differences in creep deformation at various locations on the outer casing 10. This means that the shale creep deformation exerts different squeezing forces at different locations on the outer casing 10. A single-structure outer casing 10 may be unable to accurately perform active pressure relief, or may have incidental effects on other circumferential or axial locations during pressure relief.

[0071] In this example, the outer sleeve 10 includes multiple arc plates 11. On the one hand, the multiple arc plates 11 are movable through the first hinge 12 to form a circular structure. For example, the circumferential side can be composed of three arc plates 11, and each arc plate 11 actively releases pressure on the shale creep deformation on the circumferential side. On the other hand, the multiple arc plates 11 are axially movably connected through the second hinge 13. This structure allows the outer sleeve 10 to have a certain length. Each arc plate 11 actively releases pressure on the shale creep deformation on the axial side, realizing separate pressure release of the outer sleeve on the axial and circumferential sides, avoiding mutual influence and being more targeted.

[0072] In some examples of the present invention, Figures 1 to 3 As shown, the support 60 includes:

[0073] Filler 63, filled between the outer sleeve 10 and the inner sleeve 20;

[0074] Multiple elastic members are installed on the inner side of the corresponding curved plate 11. Each elastic member has a hydraulic cylinder 61. The output end of the hydraulic cylinder 61 acts on the inner side of the curved plate 11. The oil circuit passes through between the outer sleeve 10 and the inner sleeve 20.

[0075] Specifically, the filler 63 may be compressed foam, or other materials with a certain elasticity;

[0076] Initially, the controller controls the hydraulic cylinder 61 to act on the inner side of the curved plate 11, so that the curved plate 11 can withstand an external extrusion pressure of 0MPa without deformation. When the creep extrusion pressure of the wellbore shale exceeds 0MPa, the controller can control the hydraulic cylinder 61 to retract, for example, by 10%. At the same time, the curved plate 11 has a certain compressive resistance during the retraction process. After the retraction is completed, the strain sensing element 70 senses the external shale strain and the extrusion pressure on the outer casing 10 decreases. The controller then controls the hydraulic cylinder 61 to act on the inner side of the curved plate 11 and maintain the curved plate 11 able to withstand the external extrusion pressure of 0MPa. This process of active pressure release is suitable for small and continuous creep deformation of shale.

[0077] When the creep extrusion pressure of the wellbore shale is greater than POMPa again, the hydraulic cylinder 61 then retracts a certain distance and then applies force to the inner side of the arc plate 11 to keep the arc plate 11 able to withstand the external extrusion pressure of POMPa.

[0078] Furthermore, the output end of the hydraulic cylinder 61 acts on the inner side of the arc-shaped plate 11 through the top pressure plate 62;

[0079] The elastic member further includes a spring 64, which is compressed and located between the arc-shaped plate 11 and the inner sleeve 20;

[0080] Specifically, the top pressure plate 62 contacts the inner side of the curved plate 11, which can ensure uniformity of force applied to the curved plate 11;

[0081] The elastic member is used for active support. That is, when the creep extrusion pressure of the wellbore shale is greater than P0MPa and the hydraulic cylinder 61 retracts to release the pressure, the spring 64 is squeezed and can elastically act on the curved plate 11. The curved plate 11 steel can still provide a certain compressive resistance during the retraction process of the hydraulic cylinder 61.

[0082] Furthermore, the elastic modulus E of the spring 64 is calculated as follows:

[0083] E=POS / k

[0084] Where E is the elastic modulus of spring 64, N / m 2 ; S is the surface area of ​​the curved plate 11, m 2 ; k is the stroke of the hydraulic cylinder 61, m; P0 is the compressive limit of the arc plate 11, MPa.

[0085] In some examples of the present invention, Figure 4 As shown, positioning rings 50 are fixed on the outsides of the adjacent outer sleeves 10;

[0086] The support member 30 is provided with an external thread on its circumference;

[0087] The locking sleeve 40 has an L-shaped ring structure in cross section, one side of which presses against the positioning ring 50 and the inner side of which is threadedly connected to the external thread of the support member 30, so that the outer sleeve 10 is connected to the support member 30;

[0088] Specifically, the positioning ring 50 can be fixed to the outer sleeve 10 by welding; the outermost circumference of the support member 30 is provided with an external thread, which matches the internal thread of the inner wall of the locking sleeve 40;

[0089] In this example, one L-shaped end of the locking sleeve 40 can press against the positioning ring 50, and the other end is threadedly connected to the support member 30. At this time, the support member 30 is clamped between adjacent outer casings 10. The installation of the locking sleeve 40 enables the docking of multiple sets of casing components. The docking method is convenient for disassembly and assembly, and avoids the unstable connection between adjacent casing components caused by the impact of high-temperature and high-pressure gas during methane explosion. It can also prevent the influence of long-term shale creep on the docking position of the casing components.

[0090] As explained above, a high-pressure sealing ring may be provided between the sleeve component and the support member 30 .

[0091] In some examples of the present invention, Figure 4 、 Figure 5 As shown, the support member 30 is composed of a first ring member 31, a second ring member 32, and a third ring member 33 which are coaxially arranged from outside to inside;

[0092] The middle parts of the first ring member 31, the second ring member 32, and the third ring member 33 are connected by a partition 36, and a first annular groove 34 and a second annular groove 35 are formed symmetrically between adjacent ring members;

[0093] The outer sleeve 10 is located in the first annular groove 34, and the inner sleeve 20 is inserted into the second annular groove 35. The partition 36 is provided with a through hole 37 so that adjacent first annular grooves 34 are connected to each other, and a through hole is provided so that the interiors of adjacent inner sleeves 20 are connected.

[0094] Specifically, the middle portion of the partition 36 is a through hole, which can ensure that adjacent inner sleeves 20 are connected to each other;

[0095] The second annular groove 35 formed by the second ring member 32 and the third ring member 33 may be slightly elastic, so that the adjacent inner sleeves 20 can be respectively inserted and extruded into the second annular groove 35 separated by the partition 36, and the outer sleeve 10 is located in the first annular groove 34 and can squeeze and seal the first annular groove 34;

[0096] In this example, the support member 30 is divided into a symmetrical structure by a partition 36. This symmetrical structure can be connected to adjacent casing components, so that the interiors of adjacent inner casings 20 are interconnected, and adjacent first ring bodies are interconnected. This not only realizes the interconnection of multiple sets of casing components, but also allows the controlled wires or oil circuits in the support 60 to be led out, facilitating control.

[0097] It is also noted that when the outer sleeve 10 includes multiple arc-shaped plates 11, the arc-shaped plate 11 forming a circular ring structure on the end side of the outer sleeve 10 can be located in the first annular groove 34, or a fixed ring is used on the end side of the outer sleeve 10, and this fixed ring is hinged to the other arc-shaped plates 11.

[0098] The present invention provides a control method for an active pressure-yielding anti-shale creep wellbore structure, specifically comprising the following steps:

[0099] S1: Multiple sets of casing components are placed in a borehole or wellbore. When the casing components are at a deeper position or a three-dimensional crack network is established by methane explosion, the controller controls the hydraulic cylinder 61 to act on the inner side of the curved plate 11, so that the curved plate 11 can withstand an external extrusion force of 50 MPa without deformation.

[0100] S2, based on time and wellbore shale creep deformation, the outer casing 10 is squeezed;

[0101] Each curved plate 11 matches the creep deformation of the wellbore shale at different positions in the circumferential and axial directions, and the circumferentially and axially adjacent curved plates 11 can be adjusted in real time through movable connections. The strain sensors on the curved plates 11 sense the squeezing force of the external shale creep deformation on the outer casing 10;

[0102] S3: When the creep extrusion pressure of the wellbore shale exceeds 0 MPa, the controller controls the hydraulic cylinder 61 to retract toward the center of the casing component, ensuring that the curved plate 11 has a certain compressive resistance during the retraction process. After the retraction is completed, the strain sensing element 70 senses the external shale strain and the extrusion pressure on the outer casing 10 decreases. The controller then controls the hydraulic cylinder 61 to act on the inner side of the curved plate 11, ensuring that the curved plate 11 can still withstand the extrusion pressure of 0 MPa.

[0103] S4, when the creep extrusion pressure of the shale is greater than P0MPa again, the hydraulic cylinder 61 then retracts a certain distance and then applies force to the inner side of the curved plate 11, and keeps the curved plate 11 able to withstand the external extrusion pressure of P0MPa, repeating step S3 until the controller hydraulic cylinder 61 retracts and moves to the limit position.

[0104] The above describes in detail an exemplary implementation of an active pressure-yielding anti-shale creep wellbore structure proposed by the present invention with reference to a preferred embodiment. However, those skilled in the art will understand that, without departing from the concept of the present invention, various modifications and variations can be made to the above-mentioned specific embodiments, and various technical features and structures proposed by the present invention can be combined in various ways without exceeding the scope of protection of the present invention, which is determined by the appended claims.

Claims

1. An active pressure-yielding anti-shale creep wellbore structure, characterized in that: include: Multiple sets of sleeve components are coaxially connected up and down through a support member (30), and each set of sleeve components comprises an inner sleeve (20) and an outer sleeve (10); A support (60) is provided between the inner sleeve (20) and the outer sleeve (10), and the support (60) is capable of exerting force on the inner wall of the outer sleeve (10); A strain sensing element (70) is arranged on the outer peripheral side of the outer sleeve (10) and is connected to the controller; When the strain sensing member (70) senses that the extrusion force exerted on the outer casing (10) by the creep deformation of the shale is greater than a certain value, the controller receives the strain signal and controls the support (60) to move a certain distance toward the center of the casing component, and keeps the support (60) exerting force on the inner wall of the outer casing (10); The outer sleeve (10) includes a plurality of arc-shaped plates (11); A plurality of arc-shaped plates (11) are arranged circumferentially and adjacent ones are movably connected via first hinges (12) to form a circular ring structure; Each curved plate (11) is provided with a strain sensing member (70), and the supports (60) are capable of exerting force on the curved plates (11). The support (60) includes: A filler (63) is filled between the outer sleeve (10) and the inner sleeve (20); A plurality of elastic members are installed on the inner side of the corresponding arc-shaped plate (11), and each elastic member has a hydraulic cylinder (61). The output end of the hydraulic cylinder (61) acts on the inner side of the arc-shaped plate (11), and the oil circuit of the hydraulic cylinder (61) passes through between the outer sleeve (10) and the inner sleeve (20).

2. The active pressure-yielding anti-shale creep wellbore structure according to claim 1, characterized in that: The plurality of arc-shaped plates (11) are first arranged circumferentially and then arranged vertically, and the upper and lower adjacent arc-shaped plates (11) are movably connected via a second hinge (13).

3. The active pressure-yielding anti-shale creep wellbore structure according to claim 1, characterized in that: The output end of the hydraulic cylinder (61) acts on the inner side of the arc-shaped plate (11) through the top pressure plate (62); The elastic member further comprises a spring (64), which is compressed and located between the arc-shaped plate (11) and the inner sleeve (20).

4. The active pressure-yielding anti-shale creep wellbore structure according to claim 3, characterized in that: The calculation formula of the elastic modulus E of the spring (64) is: E=P0S / k Where, S is the outer surface area of ​​the curved plate (11), m 2 ; k is the stroke of the hydraulic cylinder (61), m; P0 is the compressive strength limit of the arc plate (11), MPa.

5. The active pressure-yielding anti-shale creep wellbore structure according to any one of claims 1 to 4, characterized in that: Positioning rings (50) are fixed on the outer sides of the plurality of arc-shaped plates (11); The supporting member (30) is provided with an external thread on its circumference; The locking sleeve (40) has an L-shaped ring structure in cross section, one end of which is pressed against the positioning ring (50) and the inner side of the other end is threadedly connected to the external thread of the support member (30) so that the outer sleeve (10) is connected to the support member (30).

6. The active pressure-yielding anti-shale creep wellbore structure according to claim 5, characterized in that: The support member (30) is composed of a first ring member (31), a second ring member (32), and a third ring member (33) coaxially arranged from outside to inside; The middle parts of the first ring member (31), the second ring member (32), and the third ring member (33) are connected by a partition plate (36), and form a first annular groove (34) and a second annular groove (35) that are adjacently and symmetrically arranged; The outer sleeve (10) is located in the first annular groove (34), and the inner sleeve (20) is embedded in the second annular groove (35); the partition (36) is provided with a through hole (37) that connects adjacent first annular grooves (34) to each other, and a through hole that connects adjacent inner sleeves (20) to each other.

7. A control method for an active pressure-yielding anti-shale creep wellbore structure according to claim 1, characterized in that: The specific steps include: S1, placing multiple sets of casing components in a borehole or wellbore, when the casing components are located at a deeper position or after methane explosion establishes a three-dimensional crack network, the controller controls the hydraulic cylinder (61) to act on the inner side of the curved plate (11), so that the curved plate (11) can withstand an external squeezing force of 0.5 MPa without deformation; S2, based on time, the creep deformation of the wellbore shale will squeeze the outer casing (10); Each arc-shaped plate (11) matches the creep deformation of the wellbore shale at different positions in the circumferential direction and can be adjusted in real time through a movable connection. The strain sensing member (70) on the arc-shaped plate (11) senses the squeezing force of the external shale creep deformation on the outer casing (10); S3, when the creep extrusion pressure of the wellbore shale is greater than P0MPa, the controller controls the hydraulic cylinder (61) to retract toward the center of the casing component, and ensures that the arc plate (11) has a certain compressive resistance during the retraction process; when the retraction movement is completed, the strain sensing component (70) senses the external shale strain and the extrusion pressure on the outer casing (10) decreases, and the controller controls the hydraulic cylinder (61) to act on the inner side of the arc plate (11) and maintains that the arc plate (11) can still withstand the extrusion pressure of P0MPa; S4, when the creep squeezing pressure of the shale is greater than P0MPa again, the hydraulic cylinder (61) then retracts a certain distance and then applies force to the inner side of the curved plate (11), and keeps the curved plate (11) able to withstand the external squeezing pressure of P0MPa, and repeats step S3 until the controller hydraulic cylinder (61) retracts and moves to the limit position.

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