Anchoring and plugging structure for long well section shaft

Abstract

The invention relates to the technical field of long-well-section shaft anchoring and plugging, and discloses a long-well-section shaft anchoring and plugging structure which comprises an upper connector, a lower connector, a packing structure and an anchoring structure, and the packing structure and the anchoring structure are connected between the upper connector and the lower connector. The right end of the upper connector is connected with a cylinder sleeve through a first shear pin, a center connector is sleeved with the cylinder sleeve, the left end of the center connector is in interference fit with the upper connector, a radial through hole is formed in the middle of the center connector and communicated with the hydraulic cavity, the right side face of the cylinder sleeve is in threaded connection with a connecting sleeve, and a first lock spring is fixed to the right side face of the connecting sleeve through a pressing cap. The first lock spring is nested on a sawtooth thread on the outer wall of the middle pipe, the upper end of the middle pipe is fixedly connected with an upper rubber cylinder, and the middle pipe penetrates through the connecting sleeve and the center connector; through the cooperation of the structure, the anchoring plugging sealing integrity of the long well section shaft can be improved, the sealing failure risk is reduced, and the setting success rate is increased.

Description

Technical Field

[0001] This invention belongs to the field of long well section wellbore anchoring and plugging technology, specifically a long well section wellbore anchoring and plugging structure. Background Technology

[0002] In oil and gas well development, reliable plugging of long wellbore sections is a core technology for ensuring operational safety. Traditional plugging structures suffer from three major technical bottlenecks: 1. Sealing failure problem: Conventionally designed single-layer rubber sleeves are prone to material aging and irreversible deformation under high temperature and high pressure conditions. At the same time, they lack a compensation mechanism for the axial expansion and contraction deformation of the well barrel, resulting in rapid decay of sealing performance and insufficient sealing life.

[0003] 2. Poor anchoring adaptability: Fixed slips are difficult to match well walls of different lithologies and have insufficient adaptability. Rigid fixed slip devices are difficult to adapt to the characteristics of well walls of different geological lithologies. Slippage is likely to occur in shale formations, while in sandstone formations, pressure concentration may cause well wall damage.

[0004] 3. Inadequate setting control: Existing technologies mostly use single-stage shear pin triggering, which cannot match complex pressure profiles and cannot effectively cope with the multi-stage response requirements of complex formation pressure changes.

[0005] Therefore, we propose a long well section wellbore anchoring and plugging structure. Summary of the Invention

[0006] The purpose of this invention is to provide a long wellbore anchoring and plugging structure in order to improve the sealing integrity of long wellbore sections, reduce the risk of sealing failure, and increase the success rate of setting.

[0007] The technical solution adopted in this invention is as follows: A long well section wellbore anchoring and plugging structure includes an upper connector, a lower connector, and a sealing structure and an anchoring structure connected therebetween. The upper connector is connected to the tubing via an API standard thread, and the lower end face of the upper connector has an axial through hole. The right end of the upper connector is connected to a cylinder liner via a shear pin. A center connector is fitted inside the cylinder liner. The left end of the center connector is interference-fitted with the upper connector, and the center connector has a radial through hole in the middle that connects to the hydraulic chamber. A connecting sleeve is threaded to the right side face of the cylinder liner. A locking spring is fixed to the right side face of the connecting sleeve via a pressure cap. The locking spring is nested on the sawtooth thread on the outer wall of the intermediate tube. An upper rubber sleeve is fixedly connected to the upper end of the intermediate tube, and the intermediate tube passes through the connecting sleeve and the center connector. The sealing structure includes a central tube, a rubber sleeve one, and a spacer ring two. The central tube and the intermediate tube are coaxially sleeved to form an annular space. The rubber sleeve one and the spacer ring two are alternately stacked in the annular space. The lower end of the intermediate tube is connected to a lower rubber sleeve seat through an API standard thread. The outer wall of the lower rubber sleeve seat has a 45° inclined surface that engages with the wedge-shaped locking block. The locking block is fixed in a groove on the inner wall of the locking block connector by a shear pin two. The right end of the intermediate tube is threaded to a central tube coupling. The right end of the central tube coupling is threaded to a central tube connector. The right end of the central tube is threaded to a central tube coupling. The outer surface of the central tube coupling is provided with an upper telescopic tube. The right end of the central tube is connected to a lower telescopic tube. The central tube coupling is connected to the central connecting tube via API standard threads. The outer wall of the central connecting tube has a stepped annular groove that is interference-fitted with the inner hole of the upper connector of the rubber sleeve. The right end of the central connecting tube is fixed with a sealing assembly consisting of rubber sleeve two and spacer ring two via a rubber sleeve lower seat. A locking spring limiting sleeve is fixedly connected to the middle of the central connecting tube via shear pin three and shear pin sleeve one. The serrations on the inner wall of the locking spring limiting sleeve mesh with the outer teeth of locking spring two. A double-acting cylinder sleeve is provided on the outside of the central connecting tube. The left side of the double-acting cylinder sleeve is fixed to the upper piston via connecting screws and shear pin four. The lower piston on the right side of the double-acting cylinder sleeve adopts a conical surface fit. The hydraulic chamber is limited by shear pin five and shear pin sleeve two. The anchoring structure consists of a locking spring, a cone, a slip, and a lower central tube. The cone is linked to the lower piston via the shear pin sleeve. The slip adopts a split design and achieves radial expansion through the axial movement of the lower central tube. The upper end of the lower central tube is connected to the central connecting tube via a shear pin, and the right end of the lower central tube is connected to the lower connector using an API standard thread. A guide sleeve is embedded in the annular groove on the outer wall of the central tube and slides in cooperation with the inner hole of the lower telescopic tube.

[0008] In a preferred embodiment of the invention, an O-ring is provided at the junction of the intermediate pipe coupling with the intermediate pipe and the intermediate pipe joint.

[0009] In a preferred embodiment of the invention, the upper telescopic tube and the central tube coupling are connected by a trapezoidal thread, and an O-ring seal is provided at the mating point between the upper telescopic tube and the central tube coupling.

[0010] In a preferred embodiment of the invention, the rubber sleeve is made of high-temperature resistant rubber material and is alternately arranged with the spacer ring to form a multi-layer sealing structure.

[0011] In a preferred embodiment of the invention, the shear strengths of the first shear nail, the second shear nail, the third shear nail, the fourth shear nail, the fifth shear nail, and the sixth shear nail are 50 MPa, 60 MPa, 70 MPa, 80 MPa, 90 MPa, and 100 MPa, respectively, forming a progressive pressure response.

[0012] In a preferred embodiment of the invention, the clasp has six segments, each segment having a 45° bevel on its back side, which cooperates with the cone to achieve radial expansion.

[0013] In a preferred embodiment of the invention, the tungsten carbide teeth of the kava are arranged in a spiral pattern, with a tooth height of 2.5 mm and a tooth pitch of 5 mm.

[0014] In a preferred embodiment of the invention, the shear ring of the connecting sleeve is made of 45 steel with a shear strength of 120 MPa.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. In this invention, a multi-layer sealing system is formed by the alternating stacking structure of rubber sleeve one, rubber sleeve two, spacer ring one and spacer ring two, combined with the expansion and contraction compensation of the upper and lower telescopic tubes, thereby improving the sealing integrity and reducing the risk of sealing failure.

[0016] 2. In this invention, the segmented slip achieves dynamic matching between radial expansion force and well wall lithology through hydraulic linkage between the cone and the lower piston, in conjunction with spirally arranged tungsten carbide teeth. This adapts to the adjustment of anchoring force in shale and sandstone well sections, avoiding well wall damage.

[0017] 3. In this invention, the shearing pin system with shear strength gradient design, in conjunction with the double-acting cylinder liner, completes the setting process in three stages: shearing pin one triggers the upper isolator, shearing pin four activates the middle seal, and shearing pin six initiates anchoring. This mechanism ensures that the setting process is precisely synchronized with the wellbore pressure curve, thereby improving the success rate of setting. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the left-end structure in this invention; Figure 3 This is a schematic diagram of the right-hand portion of the structure in this invention.

[0019] Explanation of reference numerals in the attached diagram: 1. Upper connector; 2. Shear pin one; 3. Cylinder liner; 4. Center connector; 5. Connecting sleeve; 6. Pressure cap; 7. Locking spring one; 8. Upper rubber sleeve cap; 9. Intermediate tube; 10. Center tube; 11. Rubber sleeve one; 12. Spacer ring one; 13. Lower rubber sleeve seat; 14. Locking block; 15. Shear pin two; 16. Locking block connector; 17. Intermediate tube coupling one; 18. O-ring one; 19. Intermediate tube connector; 20. Upper telescopic tube; 21. Center tube coupling; 22. O-ring two; 23. Lower telescopic tube. 24. Central connecting pipe; 25. Upper connector of rubber tube; 26. Rubber tube two; 27. Spacer ring two; 28. Lower seat of rubber tube; 29. ​​Locking spring limiting sleeve; 30. Shear pin three; 31. Locking spring two; 32. Shear pin sleeve one; 33. Connecting screw; 34. Shear pin four; 35. Upper piston; 36. Double-acting cylinder liner; 37. Lower piston; 38. Shear pin five; 39. Shear pin sleeve two; 40. Locking spring three; 41. Cone; 42. Collet; 43. Lower central tube; 44. Shear pin six; 45. Guide sleeve; 46. Lower connector. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. 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.

[0021] The following will combine Figures 1-3 A detailed description of a long well section wellbore anchoring and plugging structure according to an embodiment of the present invention is provided. Example 1

[0022] Reference Figures 1-3A long-section wellbore anchoring and plugging structure includes an upper connector 1, a lower connector 46, and a sealing and anchoring structure connected therebetween. The upper connector 1 is connected to the tubing via an API standard thread, and the lower end face of the upper connector 1 has an axial through hole. The right end of the upper connector 1 is connected to a cylinder liner 3 via a shear pin 2. A center connector 4 is fitted inside the cylinder liner 3. The left end of the center connector 4 is interference-fitted with the upper connector 1, and the center connector 4 has a radial through hole in the middle that connects to the hydraulic chamber. A connecting sleeve 5 is threaded to the right side face of the cylinder liner 3. The shear ring of the connecting sleeve 5 is made of 45# steel with a shear strength of 120MPa. A locking spring 7 is fixed to the right side face of the connecting sleeve 5 via a pressure cap 6. The locking spring 7 is nested on the serrated thread on the outer wall of the intermediate tube 9. An upper rubber sleeve 8 is fixedly connected to the upper end of the intermediate tube 9, and the intermediate tube 9 passes through the connecting sleeve 5 and the center connector 4. Specifically, the upper connector 1 is connected to the tubing via an API standard thread to ensure compatibility with existing downhole tools and reduce operating costs. The axial through-hole design forms the main hydraulic channel, which, together with the radial through-hole of the center connector 4, enables bidirectional transmission of pressure fluid. The cooperation between the shear pin 2 and the cylinder liner 3 constitutes the first-stage pressure protection. When the hydraulic pressure reaches 50MPa, the shear pin is cut off, triggering the initial setting action. The engagement mechanism between the locking spring 7 and the sawtooth thread of the intermediate tube 9 achieves step-by-step locking during the downward movement of the cylinder liner, forming an anti-reverse protection.

[0023] Reference Figures 1-3 The sealing structure includes a central tube 10, a rubber sleeve 11, and a spacer ring 12. The rubber sleeve 11 is made of high-temperature resistant rubber and is alternately arranged with the spacer ring 12 to form a multi-layer sealing structure. The intermediate tube 9 is coaxially fitted with the central tube 10 to form an annular space. The rubber sleeve 11 and the spacer ring 12 are alternately stacked in this annular space. The lower end of the intermediate tube 9 is connected to a lower rubber sleeve seat 13 via an API standard thread. The outer wall of the lower rubber sleeve seat 13 has a 45° bevel that wedges with the locking block 14. The locking block 14 is fixed in a groove on the inner wall of the locking block connector 16 by a shear pin 15. The right end of the intermediate tube 9 is threadedly connected to an intermediate tube coupling 17. The right end of the intermediate pipe coupling 17 is threadedly connected to the intermediate pipe joint 19. An O-ring 18 is provided at the joint between the intermediate pipe coupling 17, the intermediate pipe 9, and the intermediate pipe joint 19. The right end of the central pipe 10 is threadedly connected to the central pipe coupling 21, and the outer surface of the central pipe coupling 21 is provided with an upper telescopic pipe 20. The right end of the central pipe 10 is connected to the lower telescopic pipe 23. Specifically, through the alternating stacking structure of the rubber sleeve 11, rubber sleeve 26, spacer 12, and spacer 27, and in conjunction with the expansion and contraction compensation of the upper telescopic pipe 20 and the lower telescopic pipe 23, a multi-layer sealing system is formed, which improves the sealing integrity and reduces the risk of sealing failure. Example 2

[0024] Reference Figures 1-3The central tube coupling 21 is connected to the central connecting tube 24 via an API standard thread. The upper telescopic tube 20 is connected to the central tube coupling 21 via a trapezoidal thread, and an O-ring seal 22 is provided at the mating point between the upper telescopic tube 20 and the central tube coupling 21. The outer wall of the central connecting tube 24 has a stepped annular groove, which is interference-fitted with the inner hole of the upper connector 25 of the rubber sleeve. The right end of the central connecting tube 24 is fixed with a sealing assembly consisting of rubber sleeve 26 and spacer ring 27 via rubber sleeve lower seat 28. A locking spring limiting sleeve 29 is fixedly connected to the middle of the central connecting tube 24 via shear pin 30 and shear pin sleeve 32. The serrations on the inner wall of the locking spring limiting sleeve 29 mesh with the outer teeth of locking spring 21. The outer side of the central connecting tube 24 is provided with The double-acting cylinder liner 36 is fixed to the upper piston 35 on the left side by connecting screws 33 and shear pins 34. The lower piston 37 on the right side of the double-acting cylinder liner 36 adopts a conical surface fit. The hydraulic chamber is limited by shear pins 38 and shear pin sleeves 39. Specifically, the stepped annular groove of the central connecting pipe 24 is interference-fitted with the upper connector 25 of the rubber sleeve. Together with the multi-layer sealing assembly composed of rubber sleeve 26 and spacer ring 27, it forms an axial-radial composite sealing structure. The rigid fixing design of the lower seat 28 of the rubber sleeve prevents the seal from being squeezed out. The locking spring limiting sleeve 29 and the serrated engagement of the locking spring 31 form a mechanical self-locking mechanism. Combined with the shear strength of shear pins 30, it achieves double anti-reverse protection after setting.

[0025] Reference Figures 1-3 The anchoring structure consists of a locking spring 40, a cone 41, a slip 42, and a lower central tube 43. The cone 41 is linked to the lower piston 37 via a shear pin sleeve 39. The slip 42 adopts a segmented design, achieving radial expansion through the axial movement of the lower central tube 43. The slip 42 has six segments, each with a 45° bevel on its back, which cooperates with the cone 41 to achieve radial expansion. The tungsten carbide teeth of the slip 42 are spirally arranged, with a tooth height of 2.5 mm and a tooth pitch of 5 mm. The upper end of the lower central tube 43 is connected to the central connecting tube 24 via a shear pin 44, and the right end of the lower central tube 43 is connected to the lower connector 46 using an API standard thread. A guide sleeve 45 is embedded in the annular groove on the outer wall of the central tube 43 and slides in contact with the inner hole of the lower telescopic tube 23. (Shear pins 1-2 and 2-15 are also mentioned.) The shear strengths of shear nails 30, 34, 38, and 44 are 50 MPa, 60 MPa, 70 MPa, 80 MPa, 90 MPa, and 100 MPa, respectively, forming a progressive pressure response. Specifically, the split slip 42, through the hydraulic linkage between the cone 41 and the lower piston 37, combined with the spirally arranged tungsten carbide teeth, achieves dynamic matching between the radial expansion force and the wellbore lithology, adapting to the adjustment of the anchoring force in shale and sandstone well sections and avoiding wellbore damage. Moreover, in this application, the shear nail system, in conjunction with the double-acting cylinder liner 36, completes the setting process in three stages: shear nail 2 triggers the upper isolator, shear nail 44 activates the middle seal, and shear nail 64 initiates anchoring. This mechanism ensures precise synchronization between the setting process and the wellbore pressure curve, improving the setting success rate.

[0026] The implementation principle of the long well section wellbore anchoring and plugging structure of this application is as follows: In this application, the upper connector 1 is connected to the oil pipe, and the lower connector 37 is connected to the check valve. As the downhole tubing is lowered to the designed depth, the surface is pressurized. After reaching a certain pressure, under the action of the hydraulic cylinder assembly, the shear pin 2-1, the intermediate pipe 9 and the intermediate pipe connector 19 are cut off respectively. The cylinder liner 3 is pushed downward to push the connecting sleeve 5, the pressure cap 6, the upper rubber sleeve cap 8, the central pipe 10, the spacer ring 12, the lower rubber sleeve seat 13, the locking block 14, the shear pin 2-15, the locking block connector 16, the intermediate pipe coupling 1-17, the O-ring 1-18 and the upper telescopic pipe 20 downward or outward, compressing the upper sealing assembly to achieve sealing and opening the slip anchoring casing. Simultaneously, the locking spring 6 and the sawtooth thread on the intermediate tube 7 are progressively locked until the setting and anchoring are completed; the shear pin 38 is cut off and pushes the lower cylinder liner 35 upward, pushing the lower rubber sleeve seat 28 through the pressure cap 33, compressing the lower sealing assembly upward. At the same time, the locking spring 312 and the sawtooth thread on the rubber sleeve core 34 are progressively locked until the lower sealing assembly is set. Continue to inject liquid and pressurize until the shear ring of the shear pin sleeve 32 is broken, realizing the sealing component and the delivery component, and remove the upper connector and the central tube and other delivery components to complete the sleeve sealing process. When unsealing, the upper slip and rubber sleeve and other components can be milled first, and then the inner hole of the central tube can be retrieved with a spear, the tubing can be lifted, and the shear pin 30 can be cut off to achieve unsealing.

[0027] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0028] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A long-hole-section wellbore anchoring and plugging structure, comprising an upper joint (1), a lower joint (46) and a plugging structure and an anchoring structure connected therebetween, characterized in that: The upper joint (1) is connected with the oil pipe through API standard thread, and the lower end surface of the upper joint (1) is provided with an axial through hole, the right end of the upper joint (1) is connected with a cylinder sleeve (3) through a shear pin (2), the inside of the cylinder sleeve (3) is sleeved with a center joint (4), the left end of the center joint (4) is in interference fit with the upper joint (1), and the middle part of the center joint (4) is provided with a radial through hole to communicate a hydraulic chamber, the right side surface of the cylinder sleeve (3) is threadedly connected with a connecting sleeve (5), the right side surface of the connecting sleeve (5) is fixedly connected with a lock spring (7) through a pressure cap (6), the lock spring (7) is nested on the sawtooth thread of the outer wall of an intermediate pipe (9), the upper end of the intermediate pipe (9) is fixedly connected with an upper rubber cylinder (8), and the intermediate pipe (9) penetrates the connecting sleeve (5) and the center joint (4); The sealing structure comprises a center pipe (10), a rubber cylinder (11) and a spacer ring (12), the intermediate pipe (9) and the center pipe (10) are coaxially sleeved to form an annular space, the rubber cylinder (11) and the spacer ring (12) are alternately stacked in the annular space, the lower end of the intermediate pipe (9) is connected with a lower rubber cylinder seat (13) through API standard thread, and the outer wall of the lower rubber cylinder seat (13) is provided with a 45° inclined surface in wedge-shaped fit with a lock block (14), the lock block (14) is fixed in the clamping groove in the inner wall of a lock block joint (16) through a shear pin (15), the right end of the intermediate pipe (9) is threadedly connected with an intermediate pipe coupling (17), the right end of the intermediate pipe coupling (17) is threadedly connected with an intermediate pipe joint (19), the right end of the center pipe (10) is threadedly connected with a center pipe coupling (21), and the outer surface of the center pipe coupling (21) is provided with an upper telescopic pipe (20), and the right end of the center pipe (10) is connected with a lower telescopic pipe (23); The center pipe coupling (21) is connected with a center connecting pipe (24) through API standard thread, the outer wall of the center connecting pipe (24) is provided with a stepped annular groove in interference fit with the inner hole of a rubber cylinder upper joint (25), the right end of the center connecting pipe (24) is fixed with a sealing assembly composed of a rubber cylinder (26) and a spacer ring (27) through a rubber cylinder lower seat (28), the middle part of the center connecting pipe (24) is fixedly connected with a lock spring limiting sleeve (29) through a shear pin (30) and a shear pin sleeve (32), the inner wall sawtooth of the lock spring limiting sleeve (29) is engaged with the outer teeth of a lock spring (31), the outer part of the center connecting pipe (24) is provided with a double-acting cylinder sleeve (36), the left side of the double-acting cylinder sleeve (36) is fixed with an upper piston (35) through a connecting screw (33) and a shear pin (34), and the right side of the double-acting cylinder sleeve (36) is in taper surface fit with a lower piston (37), and the hydraulic chamber is limited through a shear pin (38) and a shear pin sleeve (39). The anchor structure is composed of lock spring three (40), cone (41), slip (42) and lower central tube (43), the cone (41) is linked with the lower piston (37) through the shear pin sleeve two (39), the slip (42) adopts split design, realizes radial expansion through the axial movement of the lower central tube (43), the upper end of the lower central tube (43) is connected with the central connecting pipe (24) through the shear pin six (44), and the right end of the lower central tube (43) is connected with the lower joint (46) by API standard thread, the annular groove of the outer wall of the central tube (43) is embedded with a guide sleeve (45), and the lower telescopic pipe (23) is slidably connected with the inner hole of the lower telescopic pipe (23).

2. A long- borehole-section wellbore anchoring and plugging structure according to claim 1, characterized by: The O-shaped sealing ring one (18) is arranged at the joint of the intermediate pipe coupling (17), the intermediate pipe (9) and the intermediate pipe joint (19).

3. A long- borehole-section wellbore anchoring and plugging structure according to claim 1, characterized by: The upper telescopic pipe (20) is connected with the central pipe coupling (21) by trapezoidal thread, and the O-shaped sealing ring two (22) is arranged at the joint of the upper telescopic pipe (20) and the central pipe coupling (21).

4. A long- borehole-section wellbore anchoring and plugging structure according to claim 1, characterized by: The rubber cylinder (11) is made of high-temperature-resistant rubber material, and is alternately arranged with the spacer ring (12) to form a multi-layer sealing structure.

5. A long- borehole-section wellbore anchoring and plugging structure according to claim 1, characterized by: The shear strength of the shear pin one (2), the shear pin two (15), the shear pin three (30), the shear pin four (34), the shear pin five (38) and the shear pin six (44) is 50MPa, 60MPa, 70MPa, 80MPa, 90MPa and 100MPa respectively, forming a progressive pressure response.

6. A long- borehole-section wellbore anchoring and plugging structure according to claim 1, characterized by: The slip (42) is provided with six split parts, the back surface of each split part is provided with a 45° inclined surface, and the inclined surface is matched with the cone (41) to realize radial expansion.

7. A long- borehole-section wellbore anchoring and plugging structure according to claim 1, characterized by: The tungsten carbide teeth of the slip (42) are arranged in a spiral, the tooth height is 2.5mm, and the tooth pitch is 5mm.

8. A long- borehole-section wellbore anchoring and plugging structure according to claim 1, characterized by: The shear ring of the connecting sleeve (5) is made of 45# steel material, and the shear strength is 120MPa.

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