A dual-cone self-locking liner hanger device

Abstract

This invention discloses a double-cone self-locking tailpipe hanger device, belonging to the field of oil extraction technology. The device includes a central tube, a central sleeve, a second cylinder, a second piston, an upper slip, a first cylinder, a first piston, a lower slip, and an interlocking mechanism. When the upper slip opens, the whole device forms an inverted V shape, which can stably bear the downward gravity of the tailpipe string. When the lower slip opens, the whole device forms a V shape, which can reliably bear the upward axial thrust caused by the bottom hole pressure, thermal expansion, and buckling of the tubing string. The two sets of slips correspond to the load requirements in different directions. When any set of slips is subjected to an impact load and retracts slightly, it will drive the corresponding piston to move. The steel wire traction rope will pull the other set of pistons to move synchronously, causing the other set of slips to further open outward and participate in bearing the load, thus distributing the single-point load to the two sets of slips to be borne jointly.

Description

Technical Field

[0001] This invention belongs to the field of petroleum extraction technology, specifically, it relates to a double-cone self-locking tailpipe hanger device. Background Technology

[0002] Deep and ultra-deep oil and gas resources are abundant and have great potential, accounting for 34% of the total oil and gas resources. They are an important energy replacement field. As the reservoir depth increases, the formation and pressure system become more complex. High temperature and high pressure bring great challenges to cementing. Tail pipe cementing is an important technical means for cementing deep and complex wells. Tail pipe hangers are cementing tools used in cementing processes. The main function of tail pipe hangers is to fix the tail pipe near the wellhead and provide support force to ensure that the tail pipe is stable, fixed and vertically extended to the target formation, and to prevent the tail pipe from being accidentally displaced or tilted during operation.

[0003] The invention patent CN120968477A discloses a fully adaptive anchoring oil well tailpipe hanger, including an outer cylinder, a casing at the bottom of the outer cylinder, and a connecting cylinder at the top of the outer cylinder. The connecting cylinder has several through grooves inside, with mounting blocks slidably disposed within the through grooves. Slips are mounted on the mounting blocks, and protrusions are mounted on the outside of the slips. This invention converts the unidirectional linear motion of the connecting frame into the synchronous radial expansion motion of multiple sets of slips through a drive assembly. The slips slide within the through grooves via the mounting blocks, and their radial displacement is determined by the stroke of the drive assembly. This effectively adapts to tailpipes of different diameters within a certain range, improving the tool's versatility and field applicability. A locking pin driven by a first electric telescopic mechanism is inserted into a locking hole on the vertical plate, mechanically locking the positions of the first and second moving blocks, thereby fixing the entire drive assembly and slips.

[0004] The anchoring force and self-locking effect of the slips in this device are mainly designed for axial loads in one direction. However, in actual downhole operations, the tailpipe string not only has to bear huge downward gravity, but also frequently suffers upward axial thrust caused by bottom hole pressure surges, thermal expansion, and string buckling. Under reverse loads, the existing structure may fretting and loosen, causing suspension failure and leading to downhole accidents. When encountering an impact load in one direction, the device is only passively borne by the set of slips corresponding to that direction, while the other set of slips is in an idle state and cannot be activated synchronously to share the load. Under extreme conditions, there is a risk of single-point overload failure. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] To address the issues raised in the background section regarding the following technical solutions: in actual downhole operations, the tailpipe string not only bears enormous downward gravity but also frequently experiences upward axial thrust caused by bottom hole pressure surges, thermal expansion, and string buckling. Under reverse loads, existing structures may experience fretting and loosening, leading to suspension failure and downhole accidents. Furthermore, when encountering impact loads in one direction, the device is passively borne only by one set of slips corresponding to that direction, while the other set of slips remains idle and cannot be synchronously activated to share the load, posing a risk of single-point overload failure under extreme conditions. The present invention adopts the following technical solution.

[0007] A double-cone self-locking tailpipe suspension device includes a central tube, a central sleeve fixedly connected to the outer wall of the central tube, a second cylinder detachably connected to one end of the central tube, a second piston body telescopically connected to the lower end of the second cylinder body, and multiple upper slips rotatably connected to the second piston body. A first cylinder detachably connected to the other end of the central tube, a first piston body telescopically connected to the upper end of the first cylinder body, and multiple lower slips rotatably connected to the outer wall of the first piston body. The axial cross-section of the multiple upper slips when open is inverted V-shape, and the axial cross-section of the multiple lower slips when open is V-shaped. An interlocking mechanism is installed inside the central sleeve. The interlocking mechanism can cause another set of lower slips or upper slips to open outward and simultaneously bear the impact load when one set of lower slips or upper slips bears the impact load.

[0008] Preferably, the central sleeve is provided with a misalignment mechanism, which can control the upper and lower slips to open in sequence, with the upper slip opening at a certain angle first and then the lower slip opening outward.

[0009] Preferably, a locking mechanism is provided between the second cylinder, the first cylinder and the center sleeve. After the second piston and the first piston move to the seated position and contact the center sleeve, the locking mechanism rigidly fixes the first piston and the second piston to the center sleeve respectively.

[0010] Preferably, the interlocking mechanism includes a sliding plate, a steel wire traction rope, a guide wheel, and a side extension plate. The sliding plate is fixedly connected to the bottom of the second piston body in a circumferential array. The central sleeve is provided with multiple mounting chambers opposite to the position of the second piston body. The sliding plate is inserted into the corresponding mounting chamber. The end of the sliding plate is fixedly connected to the side extension plate. The steel wire traction rope is fixedly connected to the outer wall of the side extension plate. The guide wheel is rotatably connected to the interior of the chamber near the second piston body. The steel wire traction rope extends along the axial direction of the central sleeve and extends downward after adhering to the outer wall of the guide wheel. The end of the steel wire traction rope is fixedly connected to the upper end of the first piston body. When subjected to impact load, the upper slip retracts slightly, which drives the second piston body to move upward. The steel wire traction rope pulls the first piston body downward, causing the lower slip to open outward synchronously. The lower slip retracts slightly, which drives the first piston body to move upward. The steel wire traction rope pulls the second piston body downward, causing the upper slip to open outward synchronously. Thus, the lower slip and the upper slip simultaneously participate in bearing the impact load.

[0011] Preferably, the misalignment mechanism includes multiple first pins and second pins. The lower end face of the second piston body and the upper end face of the first piston body are respectively fixedly connected to the insertion part. The two ends of the central sleeve are provided with sliding chambers. The insertion part is inserted into the sliding chamber. The multiple first pins pass through the insertion parts on the central sleeve and the second piston body in a circumferential array. The multiple second pins are inserted into the insertion parts on the central sleeve and the first piston body in a circumferential array. The shearing force of the second pin is greater than that of the first pin.

[0012] Preferably, the portion of the steel wire traction rope near the first piston body is provided with a redundant part. The redundant part is in a bent state before the upper slip opens outward, and the redundant part straightens after the upper slip opens outward at a preset angle.

[0013] Preferably, the axial length of the upper slip is shorter than that of the lower slip, so that the distance the second piston needs to move is longer for the upper slip to contact the sleeve. After the upper and lower slips rotate outward in sequence and clamp with the pipe wall, the steel wire traction rope is in a taut state.

[0014] Preferably, the locking mechanism includes an insertion plate, a conical plate, a snap-fit ​​part, a insertion groove, and a spring-loaded locking plate. The insertion plate is fixedly connected in a circumferential array to the second cylinder and the end of the first cylinder near the central sleeve. The insertion grooves are arranged in a circumferential array at both ends of the central sleeve and correspond to the positions of the insertion plate. Each insertion groove has a spring-loaded locking plate fixedly connected to both sides of its interior, which is inclined towards the center of the insertion groove. The bottom of the insertion plate is fixedly connected to a conical plate. A snap-fit ​​part is provided at the connection between the conical plate and the insertion plate. When the conical plate is inserted into the insertion groove, it squeezes the spring-loaded locking plates on both sides to cause elastic deformation. When the conical plate is fully inserted, the spring-loaded locking plates on both sides pass over the snap-fit ​​part and elastically return to their original position.

[0015] Preferably, the upper and lower ends of the central sleeve are provided with multiple axial inclined grooves, the inner sides of the upper and lower slips are inserted into the corresponding inclined grooves, and the inner wall of the central tube is provided with built-in pressure transmission holes that communicate with the second cylinder and the first cylinder respectively.

[0016] Preferably, the outer surfaces of the lower and upper jaws are provided with multiple friction grooves.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In this invention, the upper slip opens to form an inverted V shape, which can stably bear the downward gravity of the tailpipe string. The lower slip opens to form a V shape, which can reliably bear the upward axial thrust caused by the bottom hole pressure, thermal expansion, and string buckling. The two sets of slips correspond to load requirements in different directions. When any set of slips is subjected to an impact load and retracts slightly, it will drive the corresponding piston body to move. The steel wire traction rope will pull the other set of piston bodies to move synchronously, so that the other set of slips will further open outward and participate in bearing the load, distributing the single-point load to the two sets of slips to be borne by both. 2. In this invention, by setting two-stage pins with different shear forces, the upper slip can be controlled to open first and then contact the sleeve without locking it. At this time, the operator can check whether the sitting position is accurate. If there is a deviation, the hanger can be lifted out smoothly for adjustment. After confirming that there is no error, the pressure can be increased to make the lower slip fully open, thus avoiding the problem that the traditional structure cannot recover from a single sitting failure. 3. In this invention, after the ground pressure is released by the seat, the piston body moves to the position. The insertion plate at the end of the cylinder body drives the conical plate to insert into the insertion groove of the center sleeve, squeezing the elastic locking plates on both sides to produce elastic deformation. When the conical plate is fully inserted, the elastic locking plate passes over the locking part and resets, rigidly fixing the piston body and the center sleeve, avoiding the risk of loosening of the locking slip caused by the free floating of the piston body. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a double-cone self-locking tailpipe suspension device according to the present invention; Figure 2 In this invention Figure 1 Enlarged structural diagram of section A; Figure 3 This is a front view structural diagram of the tailpipe suspension device in this invention; Figure 4 This is a schematic diagram of the extended posture of the Kawa in this invention; Figure 5 This is a schematic diagram of the interlocking mechanism structure in this invention; Figure 6 In this invention Figure 5 Enlarged structural diagram of section B; Figure 7 This is a schematic diagram of the locking mechanism structure in this invention; Figure 8 In this invention Figure 7 Enlarged structural diagram of section C.

[0019] The correspondence between the labels and component names in the attached figures is as follows: 100. Central tube; 101. First cylinder body; 102. First piston body; 103. Lower slip; 104. Upper slip; 105. Second cylinder body; 106. Central sleeve; 107. Inclined groove; 108. Second piston body; 109. Friction groove; 111. Insertion part; 200. Interlocking mechanism; 201. Sliding plate; 202. Steel wire traction rope; 203. Guide wheel; 204. Side extension plate; 205. Redundancy part; 206. First pin; 207. Second pin; 300. Locking mechanism; 301. Insertion plate; 302. Conical plate; 303. Snap-fit ​​part; 304. Insertion groove; 305. Spring lock plate. Detailed Implementation

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0021] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0022] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that mutually excludes other embodiments. The present invention provides the following embodiments.

[0023] like Figure 1 , Figure 2 as well as Figure 3The diagram shown is a schematic representation of a preferred embodiment of the double-cone self-locking tailpipe suspension device of the present invention. This embodiment includes a central tube 100, with a central sleeve 106 fixedly connected to the outer wall of the central tube 100. One end of the central tube 100 is detachably connected to a second cylinder 105, and the lower end of the second cylinder 105 is telescopically connected to a second piston 108. Multiple upper slips 104 are rotatably connected to the second piston 108. The other end of the central tube 100 is detachably connected to a first cylinder 101, and the upper end of the first cylinder 101 is telescopically connected to a first piston 102. Multiple lower slips 104 are rotatably connected to the outer wall of the first piston 102. 3. The upper and lower ends of the central sleeve 106 are respectively provided with multiple axial inclined grooves 107. The inner sides of the upper slip 104 and the lower slip 103 are respectively inserted into the corresponding inclined grooves 107. The inner wall of the central tube 100 is provided with built-in pressure transmission holes that communicate with the second cylinder 105 and the first cylinder 101 respectively. The outer surfaces of the lower slip 103 and the upper slip 104 are respectively provided with multiple friction grooves 109. In this embodiment, when the ball is thrown into the central tube to pressurize, the second piston 108 and the first piston 102 move relative to each other axially. The upper slip 104 and the lower slip 103 open outward through the inclined grooves 107 during the movement, and then contact the inner wall of the sleeve. They are clamped to the inner wall of the sleeve through the friction grooves 109 (e.g., Figure 4 As shown in the figure, the axial cross-sections of the multiple upper slips 104 are inverted V-shaped, and the axial cross-sections of the multiple lower slips 103 are V-shaped. When gravity descends, the upper slips 104 support the tailpipe. When the upward axial thrust is caused by the bottom hole pressure, thermal expansion, and pipe buckling, the lower slips 103 bear the impact load, thereby making the hanger more stable with respect to the pipe wall.

[0024] When encountering an impact load in one direction, only one set of lower slips 103 or upper slips 104 bears the impact load, while the other set of lower slips 103 or upper slips 104 remains idle. To ensure that both sets of lower slips 103 and upper slips 104 can bear the impact load, the specific structure can be as follows: Figure 1 In the embodiment shown, an interlocking mechanism 200 is installed inside the central sleeve 106. When one set of lower slips 103 or upper slips 104 bears the impact load, the other set of lower slips 103 or upper slips 104 opens outward to bear the impact load at the same time. In this embodiment, by setting the interlocking mechanism 200, the lower slips 103 and upper slips 104 can bear the impact load at the same time, making the tailpipe hanger more firmly fixed to the inner wall of the pipe and preventing it from falling off.

[0025] To achieve the goal of enabling the interlocking mechanism 200 to simultaneously bear the impact load when one set of lower slips 103 or upper slips 104 bears the impact load, the other set of lower slips 103 or upper slips 104 can open outwards, thus bearing the impact load at the same time, the specific structure of the interlocking mechanism 200 can be as follows: Figure 5 In the embodiment shown, the interlocking mechanism 200 includes a sliding plate 201, a steel wire traction rope 202, a guide wheel 203, and a side extension plate 204. The sliding plate 201 is fixedly connected to the bottom of the second piston body 108 in a circumferential array. The central sleeve 106 is provided with a plurality of mounting chambers opposite to the position of the second piston body 108. The sliding plate 201 is inserted into the corresponding mounting chamber. The end of the sliding plate 201 is fixedly connected to the side extension plate 204. The steel wire traction rope 202 is fixedly connected to the outer wall of the side extension plate 204. The guide wheel 203 is rotatably connected to the interior of the chamber near the second piston body 108. The steel wire traction rope 202 extends along the axial direction of the central sleeve 106 and fits against the guide wheel 204. Extending downwards and backwards from the outer wall of wheel 203, the end of the steel wire traction rope 202 is fixedly connected to the upper end of the first piston body 102. In this embodiment, when subjected to impact load, the upper slip 104 slightly retracts, causing the second piston body 108 to move upwards. The steel wire traction rope 202 then pulls the first piston body 102 downwards, causing the lower slip 103 to open outwards simultaneously. Similarly, the slight retraction of the lower slip 103 causes the first piston body 102 to move upwards, and the steel wire traction rope 202 then pulls the second piston body 108 downwards, causing the upper slip 104 to open outwards simultaneously. This allows both the lower slip 103 and the upper slip 104 to simultaneously bear the impact load, resulting in better fixation. When the hanger first engages with the inner wall mounting bracket, the interlocking mechanism 200 allows the lower slip 103 and upper slip 104 to open simultaneously. If a positional deviation occurs during the mounting process, the tailpipe hanger will be unable to be successfully retrieved. To increase trial-and-error redundancy and improve operational safety, the specific structure can be as follows: Figure 3 as well as Figure 6 In the embodiment shown, a misalignment mechanism is provided on the central sleeve 106. The misalignment mechanism can control the upper slip 104 and the lower slip 103 to open sequentially. The upper slip 104 opens at a certain angle first, and then the lower slip 103 opens outward. In this embodiment, by setting the misalignment mechanism, the upper slip 104 opens first to contact the sleeve but does not lock tightly during the hanging operation. At this time, any problems can be detected in time. If there is a problem, the tailpipe hanger can be pulled outward. After the problem is solved, it can be reinstalled. If there is no problem, the upper slip 104 can be opened outward directly, and finally the lower slip 103 and the upper slip 104 are both locked on the inner wall of the sleeve.

[0026] To achieve the goal of opening the upper slip 104 at a certain angle before the lower slip 103 opens, the specific structure of the misalignment mechanism can be as follows: Figure 3 as well as Figure 6 In the embodiment shown, the misalignment mechanism includes multiple first pins 206 and second pins 207. Insertion portions 111 are fixedly connected to the lower end face of the second piston body 108 and the upper end face of the first piston body 102, respectively. Sliding chambers are provided at both ends of the central sleeve 106, and the insertion portions 111 are inserted into the sliding chambers. Multiple first pins 206, arranged in a circumferential array, simultaneously pass through the insertion portions 111 on the central sleeve 106 and the second piston body 108. Multiple second pins 207, arranged in a circumferential array, are inserted into the insertion portions 111 on the central sleeve 106 and the first piston body 102. The shearing force of pin 207 is greater than that of pin 206. In this embodiment, during the first hanging operation, after pressurizing the central tube 100, the second piston body 108 is pushed downward to cut the first pin 206, causing the upper slip 104 to open outward at a certain angle. At this time, the extension pressure of the first piston body 102 is insufficient to cut the second pin 207. After confirming that there is no problem, as the pressure rises, the first piston body 102 cuts the second pin 207, causing the lower slip 103 to open outward, and finally realizing the function of the upper slip 104 and the lower slip 103 opening outward in a staggered manner.

[0027] Because the steel wire traction rope 202 in the interlock mechanism 200 is tightened when the second piston body 108 descends, the tension of the steel wire traction rope 202 may cause the lower slip 103 to open outward prematurely. To avoid the steel wire traction rope 202 affecting the function of the misalignment mechanism, the specific structure can be as follows: Figure 6 In the illustrated embodiment, the portion of the wire traction rope 202 near the first piston body 102 is provided with a redundant part 205. The redundant part 205 is in a bent state before the upper slip 104 opens outward. After the upper slip 104 opens outward by a preset angle, the redundant part 205 straightens. The axial length of the upper slip 104 is shorter than the axial length of the lower slip 103. In this embodiment, by providing the redundant part 205, it is possible to prevent the upper slip 104 from interfering with the interlocking mechanism 200 when it opens first. Because the axial length of the upper slip 104 is shorter than the axial length of the lower slip 103, the distance that the second piston body 108 needs to move to contact the sleeve is longer. Therefore, after the upper slip 104 and the lower slip 103 rotate outward in sequence and clamp with the pipe wall, the wire traction rope 202 is in a taut state.

[0028] After the suspension is completed and the ground pressure is released, the second piston body 108 and the first piston body 102 lose their hydraulic support and are in a free-floating state. Under strong impact loads, the locking between the lower slip 103 and the upper slip 104 and the inner wall of the casing may loosen. To avoid this situation, the specific structure can adopt the following... Figure 7 as well as Figure 8In the embodiment shown, a locking mechanism 300 is provided between the second cylinder 105, the first cylinder 101, and the central sleeve 106. After the second piston 108 and the first piston 102 move to the seated position and contact the central sleeve 106, the locking mechanism 300 rigidly fixes the first piston 102 and the second piston 108 to the central sleeve 106 respectively. The locking mechanism 300 includes an insertion plate 301, a conical plate 302, a snap-fit ​​portion 303, a insertion groove 304, and a spring-loaded locking plate 305. The insertion plate 301 is fixedly connected in a circumferential array to the ends of the second cylinder 105 and the first cylinder 101 near the central sleeve 106. The insertion groove 304 is arranged in a circumferential array on the central sleeve. At both ends of 106, and corresponding to the position of the insertion plate 301, each insertion slot 304 has elastic locking plates 305 fixedly connected to both sides of its interior, which are inclined toward the center of the insertion slot. A conical plate 302 is fixedly connected to the bottom of the insertion plate 301. A snap-fit ​​part 303 is provided at the connection between the conical plate 302 and the insertion plate 301. When the conical plate 302 is inserted into the insertion slot 304, it squeezes the elastic locking plates 305 on both sides to make them elastically deform. When the conical plate 302 is fully inserted, the elastic locking plates 305 on both sides pass over the snap-fit ​​part 303 and elastically reset. In this embodiment, by setting the locking mechanism 300, it is possible to avoid the suspension from loosening under strong impact load after the ground pressure is released.

[0029] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered to fall within the scope of protection defined by the claims submitted herein.

Claims

1. A double-cone self-locking tailpipe suspension device, comprising a central tube (100), a central sleeve (106) fixedly connected to the outer wall of the middle part of the central tube (100), a second cylinder (105) detachably connected to one end of the central tube (100), a second piston (108) telescopically connected to the lower end of the second cylinder (105), a plurality of upper slips (104) rotatably connected to the second piston (108), a first cylinder (101) detachably connected to the other end of the central tube (100), a first piston (102) telescopically connected to the upper end of the first cylinder (101), a plurality of lower slips (103) rotatably connected to the outer wall of the first piston (102), characterized in that, The axial cross section of the multiple upper slips (104) when they open is inverted V-shape, and the axial cross section of the multiple lower slips (103) when they open is V-shaped. An interlocking mechanism (200) is installed inside the central sleeve (106). When one set of lower slips (103) or upper slips (104) bears the impact load, the other set of lower slips (103) or upper slips (104) opens outward and bears the impact load at the same time.

2. The double-cone self-locking tailpipe suspension device according to claim 1, characterized in that, The center sleeve (106) is provided with a misalignment mechanism, which can control the upper slip (104) and the lower slip (103) to open in sequence. The upper slip (104) opens at a certain angle first, and then the lower slip (103) opens outward.

3. The double-cone self-locking tailpipe suspension device according to claim 1, characterized in that, A locking mechanism (300) is provided between the second cylinder (105), the first cylinder (101), and the center sleeve (106). After the second piston (108) and the first piston (102) move to the seat position and come into contact with the center sleeve (106), the locking mechanism (300) rigidly fixes the first piston (102) and the second piston (108) to the center sleeve (106) respectively.

4. The double-cone self-locking tailpipe suspension device according to claim 1, characterized in that, The interlocking mechanism (200) includes a sliding plate (201), a steel wire traction rope (202), a guide wheel (203), and a side extension plate (204). The sliding plate (201) is fixedly connected to the bottom of the second piston body (108) in a circumferential array. The central sleeve (106) is provided with multiple mounting chambers that are opposite to the position of the second piston body (108). The sliding plate (201) is inserted into the corresponding mounting chamber. The end of the sliding plate (201) is fixedly connected to the side extension plate (204). The steel wire traction rope (202) is fixedly connected to the outer wall of the side extension plate (204). The guide wheel (203) is rotatably connected to the interior of the chamber near the second piston body (108). The steel wire traction rope (202) moves along the axial direction of the central sleeve (106). The direction extends and fits against the outer wall of the guide wheel (203) and then extends downward. The end of the steel wire traction rope (202) is fixedly connected to the upper end of the first piston body (102). When subjected to impact load, the upper slip (104) will retract slightly, which will drive the second piston body (108) to move upward. The steel wire traction rope (202) will pull the first piston body (102) to move downward, so that the lower slip (103) will open outward synchronously. The lower slip (103) will retract slightly, which will drive the first piston body (102) to move upward. The steel wire traction rope (202) will pull the second piston body (108) to move downward, so that the upper slip (104) will open outward synchronously, so that the lower slip (103) and the upper slip (104) will participate in bearing the impact load at the same time.

5. The double-cone self-locking tailpipe suspension device according to claim 2, characterized in that, The misalignment mechanism includes multiple first pins (206) and second pins (207). The lower end face of the second piston body (108) and the upper end face of the first piston body (102) are respectively fixedly connected to the insertion part (111). The two ends of the central sleeve (106) are provided with sliding chambers. The insertion part (111) is inserted into the sliding chamber. Multiple first pins (206) pass through the insertion part (111) on the central sleeve (106) and the second piston body (108) in a circumferential array. Multiple second pins (207) are inserted into the insertion part (111) on the central sleeve (106) and the first piston body (102) in a circumferential array. The shearing force of the second pin (207) is greater than that of the first pin (206).

6. The double-cone self-locking tailpipe suspension device according to claim 4, characterized in that, The steel wire traction rope (202) near the first piston body (102) is provided with a redundant part (205). The redundant part (205) is bent before the upper slip (104) opens outward. After the upper slip (104) opens outward at a preset angle, the redundant part (205) straightens.

7. The double-cone self-locking tailpipe suspension device according to claim 6, characterized in that, The axial length of the upper slip (104) is shorter than that of the lower slip (103). The distance that the second piston body (108) needs to move to contact the sleeve is longer. After the upper slip (104) and the lower slip (103) rotate outward in sequence and clamp with the pipe wall, the wire traction rope (202) is in a taut state.

8. The double-cone self-locking tailpipe suspension device according to claim 3, characterized in that, The locking mechanism (300) includes an insertion plate (301), a conical plate (302), a snap-fit ​​part (303), a insertion slot (304), and a spring-loaded locking plate (305). The insertion plate (301) is fixedly connected in a circumferential array to the second cylinder (105) and the end of the first cylinder (101) near the central sleeve (106). The insertion slots (304) are arranged in a circumferential array at both ends of the central sleeve (106) and correspond to the positions of the insertion plates (301). The inner sides of each insertion slot (304) are... A spring-loaded locking plate (305) inclined towards the center of the insertion slot is fixedly connected. A conical plate (302) is fixedly connected to the bottom of the insertion plate (301). A snap-fit ​​part (303) is provided at the connection between the conical plate (302) and the insertion plate (301). When the conical plate (302) is inserted into the insertion slot (304), it squeezes the spring-loaded locking plates (305) on both sides to produce elastic deformation. When the conical plate (302) is fully inserted, the spring-loaded locking plates (305) on both sides pass over the snap-fit ​​part (303) and elastically reset.

9. The double-cone self-locking tailpipe suspension device according to claim 1, characterized in that, The upper and lower ends of the center sleeve (106) are respectively provided with multiple axial inclined grooves (107). The inner sides of the upper slip (104) and the lower slip (103) are respectively inserted into the corresponding inclined grooves (107). The inner wall of the center tube (100) is provided with built-in pressure transmission holes that communicate with the second cylinder (105) and the first cylinder (101) respectively.

10. The double-cone self-locking tailpipe suspension device according to claim 9, characterized in that, The outer surfaces of the lower slip (103) and the upper slip (104) are respectively provided with multiple friction grooves (109).

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