CN113802994A

CN113802994A - Suspension device

Info

Publication number: CN113802994A
Application number: CN202010534819.1A
Authority: CN
Inventors: 侯治民; 雷炜; 陈琛; 崔警宇; 谢志; 严焱诚; 董海峰; 刘涛; 范培杰
Original assignee: China Petroleum and Chemical Corp; Sinopec Southwest Oil and Gas Co
Current assignee: China Petroleum and Chemical Corp; Sinopec Southwest Oil and Gas Co
Priority date: 2020-06-12
Filing date: 2020-06-12
Publication date: 2021-12-17

Abstract

The present invention provides a suspension device comprising: the releasing mechanism comprises a first central pipe, and both ends of the first central pipe are respectively connected with an upper joint and a ball seat; the elastic sheet is connected with the upper joint; the first shearing pin passes through an elastic sheet supporting ring fixedly connected with the upper joint; the anchoring mechanism is connected with the releasing mechanism in a plug-in manner and comprises a tieback cylinder; the second central tube is connected to the lower end of the tieback cylinder; the slip sleeve is sleeved outside the second central pipe, a plurality of slips are mounted at the upper end of the slip sleeve, and the slips are in conical surface fit with the tie-back cylinder; the slip sleeve can push the slip to move upwards and radially outwards to be spread when drilling fluid reaches first pressure through the ball seat suppressed pressure, so that the slip and the sleeve outside the suspension device form anchoring, the elastic sheet support ring is constructed to be capable of shearing a first shearing pin and moving downwards when drilling fluid pressure in the first central pipe reaches second pressure, so that the elastic sheet support ring is separated from radial support of the elastic sheet, releasing is completed, and the first pressure is smaller than the second pressure.

Description

Suspension device

Technical Field

The invention relates to the technical field of oil and gas drilling and exploitation tools, in particular to a suspension device.

Background

With the continuous development of oil and gas reservoir development engineering, oil and gas exploitation is gradually promoted to a low-permeability compact reservoir, and exploitation wells are deeper and deeper, particularly horizontal sections of horizontal wells are longer and longer. Therefore, in the process of running the pipe column, the friction force of the pipe column at the horizontal section is large, so that the running difficulty of the pipe column is large. Therefore, it is usually necessary to run in two runs, specifically, the lower part of the pipe string is sent to a predetermined position by using a drill pipe or a drill collar and then is released, and the upper part of the pipe string is directly hung by using a tail pipe or is connected back to the upper pipe string.

However, there are still some problems with the existing suspension devices. For example, traditional linkage's structure is comparatively complicated, appears giving up easy not successful pit shaft complex conditions such as, leads to giving up to become the power difference, and operating condition is complicated in the pit shaft, and the tubular column is gone into the in-process and is connected unstably because of vibrations easily down to lead to the anchor unstable, and then lead to giving up, anchor inefficiency, influence linkage's normal construction.

Disclosure of Invention

In view of the above technical problems, the present invention aims to provide a suspension device, which can effectively avoid the complex situations of pipe column jamming, unsuccessful releasing and unstable anchoring during the running process, greatly improve the releasing success rate, and enhance the anchoring stability.

To this end, according to the invention, a suspension device is provided comprising: a release mechanism, the release mechanism comprising: the upper end of the first central pipe is fixedly connected with an upper joint, and the lower end of the first central pipe is fixedly connected with a ball seat; the elastic sheet is sleeved on the outer side of the first central pipe and is fixedly connected with the upper joint; the elastic sheet support ring is used for providing radial support for the elastic sheet and is fixedly connected with the upper joint through a first shearing pin; the cartridge type is connected at the anchoring mechanism of the downstream end of the releasing mechanism, the anchoring mechanism comprises: the tieback cylinder can form clamping connection with the elastic sheet; the second central tube is fixedly connected to the lower end of the tieback cylinder; the slip sleeve is sleeved outside the second central pipe, a plurality of slips are uniformly distributed at the upper end of the slip sleeve in the circumferential direction, and the slips are connected with the lower end face of the return cylinder in a conical surface matching manner; the slip sleeve is configured to push the slip to move upwards when drilling fluid in the second central pipe is suppressed through the ball seat to reach a first pressure, so that the slip is radially outwards propped under the action of conical surface fit, the slip and a sleeve outside the suspension device form anchoring, the elastic sheet support ring is configured to cut the first shearing pin and move downwards when the drilling fluid pressure in the first central pipe reaches a second pressure, so that the elastic sheet support ring is separated from radial support of the elastic sheet, the connecting back cylinder is separated from the elastic sheet to complete releasing, and the first pressure is smaller than the second pressure.

In one embodiment, be equipped with first step on the internal wall face of top connection be formed with inclosed first annular cavity between first step, shell fragment support ring with first center tube be equipped with first discharge orifice on the lateral wall of first center tube with first annular cavity corresponds, wherein, drilling fluid in the first center tube passes through first discharge orifice gets into first annular cavity to form axial decurrent pressure to the up end of shell fragment support ring under the suppress pressure effect, cut first shear pin and down when reaching the second pressure.

In one embodiment, the elastic sheet is sleeved outside the elastic sheet support ring, the lower ends of the outer wall surfaces of the elastic sheet and the elastic sheet support ring are respectively provided with a first annular boss and a second annular boss which extend outwards in the radial direction, the inner wall of the tieback cylinder is provided with a groove which can be matched with the first annular boss, and in an initial state, the first annular boss is matched and clamped with the groove under the radial supporting action of the second annular boss, so that the anchoring mechanism is connected with the releasing mechanism through the tieback cylinder.

In one embodiment, the outer wall of the central tube is provided with a protrusion extending radially outwards to form a first limit end surface, the inner wall surface of the tieback cylinder is provided with a first shoulder to form a second limit end surface, the first limit end surface and the second end surface are configured into adaptive inclined surfaces, and the first limit end surface is in contact with the second limit end surface in an initial state so as to form axial limit for the first central tube.

In one embodiment, a second step is arranged on the outer wall of the second central pipe, a second shoulder is arranged on the inner wall of the slip sleeve, a closed second annular cavity is formed between the second step and the second shoulder, and a second overflowing hole is arranged on the side wall, corresponding to the second annular cavity, of the second central pipe, wherein drilling fluid from the first central pipe can enter the second annular cavity through the second overflowing hole and form axially upward pressure on the second shoulder under the pressure holding effect so as to push the slips to move upwards and radially outwards prop open, so that the slips and a sleeve outside the suspension device form anchoring.

In one embodiment, the inner wall of the upper end of the slip is configured into a first conical surface, the outer wall of the lower end of the tieback cylinder is configured into a second conical surface which can be matched with the first conical surface, and the slip can be radially outwards expanded under the action of the first conical surface and the second conical surface when going upwards.

In one embodiment, the ball seat and the first center pipe are fixedly connected through a cylindrical center pipe extension piece, a closed gap is formed among the center pipe extension piece, the second center pipe and the ball seat, the gap is communicated with the second overflowing hole, and a plurality of through holes capable of being communicated with the gap are formed in the side wall of the center pipe extension piece.

In one embodiment, a ratchet ring is fixedly connected to the lower end of the slip sleeve, and a ratchet capable of being matched with the ratchet ring is arranged on the corresponding outer wall of the second central tube, and the ratchet ring can move upwards along with the slip sleeve and form downward locking under the action of the ratchet.

In one embodiment, a lower joint is fixedly connected to the lower end of the second central pipe, a fixed connection is formed between the ratchet ring and the lower joint through a second shear pin, and the ratchet ring shears the second shear pin when the drilling fluid pressure in the second annular cavity reaches the first pressure and moves upwards along with the slip sleeve.

In one embodiment, the ratchet is fixedly attached to the outer wall of the second base pipe by a third shear pin, and the second base pipe is capable of shearing the third shear pin under a deblocking pressure to cause the slip bowl to descend relative to the second base pipe and retract the slips to complete the deblocking.

Compared with the prior art, the invention has the advantages that:

according to the suspension device disclosed by the invention, the releasing is carried out by combining a spring plate supporting type structure with a liquid pressure pushing mode, the hydraulic transmission acting force is large and stable, the reliability of the releasing can be effectively ensured, the complex conditions of dead locking, unsuccessful releasing and the like in the running-in process of a tubular column are effectively avoided, and the releasing success rate is greatly improved. The anchoring mechanism adopts a hydraulic transmission combined rail type slip structure, the annular space can be guaranteed to pass through liquid under the condition of reliable anchoring, and the slip can only move upwards by adopting a ratchet structure, so that the slip is not moved under the condition that no pressure is built in the pipe, the complex condition of the pipe column in the running-in process is effectively avoided, and the anchoring stability is obviously enhanced. In addition, the suspension device has stable structure, stable anchoring and high releasing success rate, greatly improves the working efficiency of the suspension device and is very favorable for underground production operation.

Drawings

The invention will now be described with reference to the accompanying drawings.

Fig. 1 shows the structure of a suspension device according to the present invention.

Figure 2 shows the structure of the release mechanism in the suspension shown in figure 1.

Figure 3 is a schematic view of the installation of slips in the suspension of figure 1.

Fig. 4 shows the anchoring of the suspension device.

Figure 5 shows the suspension in a released state.

Figure 6 shows the suspension after its release.

In the present application, the drawings are all schematic and are used only for illustrating the principles of the invention and are not drawn to scale.

Detailed Description

The invention is described below with reference to the accompanying drawings.

In this application it is to be noted that the end of the suspension device lowered into the wellbore close to the wellhead is defined as the upper end or similar and the end remote from the wellhead is defined as the lower end or similar.

Fig. 1 shows the structure of a suspension 100 according to the invention. As shown in FIG. 1, suspension 100 includes a release mechanism 10 and an anchor mechanism 20 that is in plug-in connection with release mechanism 10. After the suspension device 100 is placed in a working position in a shaft, the suspension device is anchored with a casing through the anchoring mechanism 20, and after the anchoring mechanism 20 is anchored with the casing, the suspension device is released through the releasing mechanism 10, so that the releasing of the suspension device 100 is realized.

As shown in fig. 1 and 2, the releasing mechanism 10 includes a first base pipe 11. An upper joint 12 is fixedly connected to the upper end of the first center pipe 11 by a screw. An axial mounting surface facing downward is provided on the inner wall of the upper joint 12, and the upper end surface of the first center tube 11 is fixedly mounted in contact with the axial mounting surface. The lower end of the upper connector 12 is fixedly connected with a spring plate 14, the lower end of the upper connector 12 is constructed into a positive step-shaped connecting buckle, and the upper end of the spring plate 14 is constructed into a negative step-shaped connecting buckle. The elastic sheet 14 and the upper connector 12 are fixedly connected through the matching installation of the positive step-shaped connecting buckle and the negative step-shaped connecting buckle. A spring plate support ring 15 is further disposed between the spring plate 14 and the first central tube 11 in the radial direction, and the spring plate support ring 15 is used for providing a radially outward supporting force for the spring plate 14. In the initial state, the spring support ring 15 is fixedly connected to the upper connector 12 by means of the first shear pin 16.

In this embodiment, the elastic sheet is sleeved outside the elastic sheet support ring, a first annular boss 141 extending radially outward is disposed at the lower end of the outer wall surface of the elastic sheet 14, and a second annular boss 151 extending radially outward is disposed at the lower end of the outer wall surface of the elastic sheet support ring 15. In an initial state, the spring plate 14 is sleeved outside the spring plate support ring 15, and the second annular boss 151 correspondingly abuts against an inner wall surface of the spring plate 14 corresponding to the first annular boss 141, so that a radially outward supporting force is formed on the first annular boss 141. Thereby, the releasing mechanism 10 and the anchoring mechanism 20 are connected through the elastic sheet 14.

The side wall of the spring 14 is provided with a spring assembly hole 142, the side wall of the spring support ring 15 is provided with a spring support ring assembly hole 152, and the spring assembly hole 142 can be adapted to the spring support ring assembly hole 152. During the installation process, a special tool is used to pass through the clip assembly holes 142 and the clip support ring assembly holes 152, thereby sliding the clip support ring 15 to the top end and causing the second annular projection 151 to exert a radially outward supporting force on the first annular projection 141.

Further, a first step is provided on the inner wall surface of the upper joint 12 with the end surface facing downward. A first closed annular cavity 30 is formed between the first step, the first center tube 11 and the upper end face of the spring support ring 15. Meanwhile, a first overflowing hole 111 penetrating through the side wall of the first central pipe 11 is formed in the side wall of the first central pipe 11 corresponding to the first annular cavity 30, and the first overflowing hole 111 communicates the central passage of the first central pipe 11 with the first annular cavity 30. When the pressure of the drilling fluid in the first central tube 11 reaches a predetermined second pressure, the upper end face of the spring support ring 15 shears the first shear pin 16 and moves downward under the pressure of the drilling fluid, so that the spring support ring 15 is separated from the radial support of the spring 14. Thereby, the anchoring mechanism 20 is disengaged from the striking plate 14, thereby completing the release.

In order to ensure the sealing performance of the first annular cavity 30, a sealing member may be disposed between the spring support ring 15 and the upper joint 12 and the first central tube 11.

As shown in fig. 2, a ball seat 13 is fixedly coupled to a lower end of the first center pipe 11. The ball seat 13 is fixedly connected to the first base pipe 11 by a base pipe extension 112. In one embodiment, the base pipe extension 112 is threadably secured to the first base pipe 11 and the ball seat 13 is threadably secured to the first base pipe 11. To ensure the sealing between the first base pipe 11 and the base pipe extension 112, a sealing element may be provided at the connection of the first base pipe 11 and the base pipe extension 112. The function of the ball seat 13 will be described below.

As shown in fig. 1, the anchoring mechanism 20 includes a tieback cylinder 21 and a second center tube 22 fixedly attached to a lower end of the tieback cylinder 21. The release mechanism 10 forms a cartridge connection with a tieback cartridge 21. The inner wall of the upper end of the tieback cylinder 21 is provided with a groove 211, and the groove 211 can be matched with the first annular boss 141 on the elastic sheet 14. In the initial state, the first annular boss 141 of the spring 14 is fittingly engaged with the groove 211 on the inner wall of the tieback cylinder 21 under the radial supporting action of the second annular boss 151 of the spring support ring 15, so that the anchoring mechanism 20 forms a snap-fit connection with the releasing mechanism 10 through the tieback cylinder 21. And, after the spring plate support ring 15 is disengaged from the radial support of the spring plate 14, the first annular boss 141 of the spring plate 14 is not subjected to radially outward supporting force, so that the anchoring mechanism 20 is disengaged from the spring plate 14 to complete releasing.

In the present embodiment, a first shoulder is provided on an inner wall surface of the tieback cylinder 21 near the lower end, thereby forming a second stopper end surface 212. Meanwhile, a protrusion 114 extending radially outward is provided on the outer wall of the first center pipe 11, thereby forming a first stopper end surface 115. The first limiting end face 115 can form adaptive butt joint with the second limiting end face 212, so that the releasing mechanism 10 is inserted into the tieback cylinder 21, and axial limiting is formed through the first limiting end face 115 and the second limiting end face 212. In one embodiment, the first limiting end surface 115 and the second limiting end surface 212 are configured as adaptable inclined surfaces, and the first limiting end surface 115 contacts the second limiting end surface 212 in an initial state, thereby forming an axial limit for the first central tube.

An annular projection having an outer diameter equal to the inner diameter of the second center tube 22 is provided on the outer wall surface of the center tube extension 112. Also, the outer diameter of the ball seat 13 is equal to the inner diameter of the second center tube 22, thereby forming a sealed gap between the center tube extension 112 and the second center tube 22 in the radial direction and between the annular protrusion and the ball seat 13 in the axial direction. Meanwhile, a plurality of through holes 113 are formed in the sidewall of the central pipe extension 112 corresponding to the annular space, and the through holes 113 communicate with the inner passage and the slit of the central pipe extension 112. In order to ensure the tightness of the gap, a sealing member may be provided between the annular protrusion and the second center tube 22, and between the ball seat 13 and the second center tube 22. The function of the slit is explained below.

As shown in fig. 1, the second center tube 22 is fixedly connected to the tieback cylinder 21 by a screw thread. The inner wall surface of the lower end of the connecting back cylinder 21 is provided with a downward step surface, the inner wall is provided with an internal thread, and the upper end of the second central tube 22 is provided with an external thread. The second central tube 22 and the tie-back cylinder 21 are connected with each other in a matching manner through internal threads and external threads, and the upper end face of the second central tube 22 is abutted against the step face, so that fixed connection is formed.

According to the invention, a slip sleeve 23 is sleeved on the outer wall of the second center tube 22. An upwardly facing second step is provided on the outer wall surface of the second central tube 22, while a downwardly facing second shoulder is provided on the inner wall of the slip sleeve 23, so that a closed second annular cavity 40 is formed between the second step and the second shoulder. A second flow hole 221 is formed in the side wall of the second center tube 22 corresponding to the second annular cavity 40, and the second flow hole 221 communicates the gap between the center tube extension 112 and the second center tube 22 and the second annular cavity 40. Thereby, the second annular chamber 40 communicates with the inner passage of the second center pipe 22 through the second flow hole 221, the slit, and the through hole 113, so that the drilling fluid from the first center pipe 11 can enter the second annular chamber 40 through the through hole 113, the slit, and the second flow hole 221 in order. When the drilling fluid pressure from within the first base pipe 11 reaches a predetermined first pressure, the drilling fluid in the second annular chamber 40 exerts an upward pressure on the end face of the second shoulder of the slip sleeve 23 and is able to push the slip sleeve 23 upwards. Wherein the first pressure is less than the second pressure.

As shown in fig. 1, the anchoring mechanism 20 further includes a plurality of slips 24 mounted at the upper end of the slip bowl 23. The slip sleeve 23 is provided with a mounting groove, and the slips 24 are correspondingly mounted in the mounting groove. Thus, the slips 24 are pushed to travel synchronously upward as the slip sleeve 23 travels upward. Figure 3 shows a schematic view of the installation configuration of one of the slips 24. The slips 24 are connected with the lower end face of the tieback cylinder 21 in a conical surface fit mode. The inner wall surface of the upper end of the slips 24 is formed into a first tapered surface, and the outer wall surface of the lower end surface of the return cylinder 21 is formed into a second tapered surface capable of fitting the first tapered surface of the slips 24. When the slip bowl 23 pushes the slips 24 up, the slips 24 are radially outwardly spread by the first and second tapered surfaces until the slips 24 are anchored to the casing outside the suspension 100.

According to the present invention, a ratchet ring 25 is fixedly connected to the lower end of the slip cover 23. In one embodiment, the ratchet ring 25 is threadedly connected to the slip bowl 23 to form a secure connection. Meanwhile, ratchets 26 capable of fitting the ratchet ring 25 are provided on the corresponding outer wall of the second center tube 22. A lower joint 27 is fixedly connected to the lower end of the second central tube 22, and the lower joint 27 is fixedly connected to the second central tube 22 by a threaded connection. In order to ensure the sealing between the lower joint 27 and the second center tube 22, a sealing member is provided between the lower joint 27 and the second center tube 22.

In the initial state, the lower end of the ratchet ring 25 is fixedly connected to the lower joint 27 by the second shear pin 28. When the drilling fluid pressure in the second annular cavity 40 reaches the first pressure, the slip sleeve 23 drives the ratchet ring 25 to shear the second shear pin 28 and then move upwards under the action of the drilling fluid pressure, and the ratchet ring 25 moves upwards synchronously with the slip sleeve 23. During the process that the ratchet ring 25 moves up with the slip bowl 23, the ratchet ring 25 engages the ratchet 26 and forms a down lock under the action of the ratchet 26, thereby preventing the slips 24 from backing back to avoid anchoring failure.

In one embodiment, ratchet 26 is fixedly attached to the outer wall of second center tube 22 by third shear pin 19. The second base pipe 22 can shear the third shear pin 29 under the unsetting pressure to allow the slip sleeve 23 to travel down the second base pipe 22 and to retract the slips 24 to complete the unsetting.

When the suspension 100 according to the present invention is assembled, the anchoring mechanism 20 is first assembled with the slips 24 in an initial retracted state. Then, the releasing device 10 is assembled, and the elastic sheet support ring 15 and the elastic sheet 14 are sequentially sleeved and installed outside the first central tube 11. Thereafter, the releasing device 10 is inserted into the tieback pipe 21 until the first limit end surface 115 of the first center pipe 11 contacts the second limit end surface 212 on the inner wall of the tieback pipe 21, and a special tool is used to pass through the spring piece assembly hole 142 and the spring piece support ring assembly hole 152, thereby sliding the spring piece support ring 15 to the top end, so that the second annular boss 151 forms a radially outward supporting force to the first annular boss 141. Therefore, the first annular boss 141 on the elastic sheet 14 is matched and clamped with the groove 211 on the tieback cylinder 21, so that the anchoring mechanism 20 is in clamping connection with the releasing mechanism 10 through the tieback cylinder 21. Then, the first shear pin 16 is installed, so that the spring support ring 15 is fixedly connected with the upper connector 12 through the first shear pin 16. Thereby, the assembly of the suspension device 100 is completed. At this time, the suspension 100 is in the initial state. Fig. 1 shows a configuration of the suspension device 100 in an initial state.

Briefly describing the operation of the suspension 100 according to the present invention, first, the suspension 100 is assembled and connected to a pipe string. The suspension device 100 is then lowered through the tubing string to the desired working formation in the wellbore. At this time, the suspension 100 is in the initial state.

Thereafter, the string is pressurized, or a separate pressure ball is dropped from the wellhead to the ball seat, so that the drilling fluid entering the suspension 100 flows through the first base pipe 11 and through the base pipe extension 112. Drilling fluid in the center tube extension 112 passes through the throughbore 113, the slots, and the second flow orifice 221 in sequence and into the second annular chamber 40. Along with the pipe string is suppressed, the pressure of the drilling fluid in the second annular cavity 40 is continuously increased, when the pressure of the drilling fluid in the second annular cavity 40 reaches a predetermined first pressure, the drilling fluid forms an upward pressure on the end face of the second shoulder of the slip sleeve 23, and drives the ratchet ring 25 to shear the second shear pin 28, so as to push the slip sleeve 23 to move upwards. As the slip bowl 23 pushes the slips 24 up, the slips 24 are radially outwardly spread by the first and second tapered surfaces until the slips 24 engage the casing outside the suspension 100 to form an anchor. Thereby completing the slip anchoring. At this time, the suspension 100 is in an anchored state. Fig. 4 shows the structure of the suspension 100 in an anchored state.

Thereafter, the pressure continues to be held, and the pressure in the suspension 100 continues to rise. The drilling fluid in the first base pipe 11 enters the first annular chamber 30 through the first flow passage 111. When the pressure of the drilling fluid in the first central tube 11 reaches a predetermined second pressure, the upper end face of the spring support ring 15 shears the first shear pin 16 and moves downward under the pressure of the drilling fluid, so that the spring support ring 15 is separated from the radial support of the spring 14. At this time, the snap connection between the first annular projection 141 of the resilient tab 14 and the groove 211 of the tieback cylinder 21 is disabled. At this time, the suspension 100 is in the state at the time of release. Fig. 5 shows the configuration of the suspension 100 in the state when it is released. Then, the first annular boss 141 on the shrapnel 14 is disengaged from the groove 211 on the tieback cylinder 21, so that the anchoring mechanism 20 is disengaged from the shrapnel 14, thereby completing the pipe column releasing. At this time, the suspension 100 is in the released state. Fig. 6 shows the configuration of the suspension 100 in a released state.

The suspension device 100 according to the invention can be used as a liner hanger alone or as a completion string with a run-back, and a packer below the hanger 100 can also be used as a suspension packer.

The suspension device 100 provided by the invention adopts a spring plate support type structure and combines a liquid pressure pushing mode to release the hands, the hydraulic transmission acting force is large and stable, the reliability of the release can be effectively ensured, the complex conditions of dead locking, unsuccessful release and the like in the running-in process of a tubular column are effectively avoided, and the success rate of the release is greatly improved. The anchoring mechanism 20 adopts a hydraulic transmission combined rail type slip structure, which can ensure that liquid passes through the annular space under the condition of reliable anchoring, and adopts a ratchet structure to ensure that the slip can only move upwards, thereby ensuring that the slip is not moved under the condition that pressure is not built in the pipe, effectively avoiding the complex condition of the pipe column in the process of running in, and obviously enhancing the anchoring stability. In addition, the suspension device 100 has stable structure, stable anchoring and high releasing success rate, greatly improves the working efficiency of the suspension device 100 and is very favorable for underground production operation.

Finally, it should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and do not limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing examples, or that equivalents may be substituted for elements thereof. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A suspension device comprising:

a releasing mechanism (10), the releasing mechanism comprising:

the upper end of the first central pipe (11) is fixedly connected with an upper joint (12), and the lower end of the first central pipe is fixedly connected with a ball seat (13);

the elastic sheet (14) is sleeved on the outer side of the first central pipe and is fixedly connected with the upper joint;

the spring plate supporting ring (15) is used for providing radial support for the spring plate and is fixedly connected with the upper joint through a first shearing pin (16);

an anchoring mechanism (20) cartridge-connected at a downstream end of the releasing mechanism, the anchoring mechanism comprising:

a tieback cylinder (21) which can form a clamping connection with the elastic sheet;

a second central tube (22) fixedly connected to the lower end of the tieback cylinder; and

the slip sleeve (23) is sleeved outside the second central pipe, a plurality of slips (24) are uniformly distributed at the upper end of the slip sleeve in the circumferential direction, and the slips are connected with the lower end face of the return cylinder in a conical surface matching mode;

wherein the slip sleeve is configured to push the slips upward when the drilling fluid in the second center tube reaches a first pressure by being held down by the ball seat, so that the slips are radially outwardly spread under the conical surface fit, thereby anchoring the slips with the casing outside the suspension,

the spring plate support ring is configured to shear the first shear pin and descend when the drilling fluid pressure in the first central pipe reaches a second pressure, so that the spring plate support ring is separated from radial support of the spring plate, the tieback cylinder is separated from the spring plate to complete releasing,

the first pressure is less than the second pressure.

2. The suspension device according to claim 1, wherein a first step is arranged on the inner wall surface of the upper joint, a closed first annular cavity (30) is formed among the first step, the spring plate support ring and the first central pipe, a first overflowing hole (111) is arranged on the side wall of the first central pipe corresponding to the first annular cavity,

drilling fluid in the first central pipe enters the first annular cavity through the first overflowing hole, and forms axial downward pressure on the upper end face of the elastic sheet support ring under the pressure building effect, and the first shearing pin is sheared and descends until the second pressure is reached.

3. The suspension device according to claim 1, wherein the spring plate is sleeved outside the spring plate support ring, the lower ends of the outer wall surfaces of the spring plate and the spring plate support ring are respectively provided with a first annular boss (141) and a second annular boss (151) which extend outwards in the radial direction, the inner wall of the tieback cylinder is provided with a groove (211) which can be matched with the first annular boss,

in an initial state, the first annular boss is matched and clamped with the groove under the radial supporting action of the second annular boss, so that the anchoring mechanism is connected with the releasing mechanism through the tieback cylinder.

4. A suspension arrangement according to claim 1, characterized in that the outer wall of the central tube is provided with a radially outwardly extending protrusion (114) to form a first stop face (115), and the inner wall surface of the tieback cylinder is provided with a first shoulder to form a second stop face (212),

the first limit end face and the second limit end face are configured into adaptive inclined faces, and the first limit end face is in contact with the second limit end face in an initial state, so that the first central pipe is axially limited.

5. The suspension device according to claim 1, characterized in that a second step is provided on the outer wall of the second center tube and a second shoulder is provided on the inner wall of the slip sleeve, a closed second annular cavity (40) is formed between the second step and the second shoulder, a second overflow hole (221) is provided on the side wall of the second center tube corresponding to the second annular cavity,

drilling fluid from the first center pipe can enter the second annular cavity through the second overflowing hole, and forms axial upward pressure on the second shoulder under the pressure building effect so as to push the slips to move upwards and expand radially outwards, and therefore the anchoring effect is formed between the drilling fluid and the casing pipe outside the suspension device.

6. A suspension arrangement according to claim 5, wherein the inner wall of the upper end of the slip is configured as a first tapered surface and the outer wall of the lower end of the tieback is configured as a second tapered surface adapted to the first tapered surface, the slip being able to expand radially outwardly on ascent under the action of the first and second tapered surfaces.

7. The suspension device according to claim 1, characterized in that the ball seat is fixedly connected to the first center tube by a cylindrical center tube extension, and a closed gap is formed between the center tube extension, the second center tube and the ball seat, the gap communicating with the second overflowing hole, and a plurality of through holes (113) communicating with the gap are provided on a side wall of the center tube extension.

8. Suspension arrangement according to claim 1, characterized in that a ratchet ring (25) is fixedly connected to the lower end of the slip sleeve and on the corresponding outer wall of the second central tube there are arranged ratchet teeth (26) which can be adapted to the ratchet ring, which can move upwards with the slip sleeve and form a downward lock under the action of the ratchet teeth.

9. Suspension device according to claim 8, characterized in that a lower joint (27) is fixedly connected to the lower end of the second central tube, the ratchet ring and the lower joint forming a fixed connection by means of a second shear pin (28),

and the ratchet ring shears the second shearing pin when the pressure of the drilling fluid in the second annular cavity reaches the first pressure, and the ratchet ring ascends along with the slip sleeve.

10. A suspension arrangement according to claim 8, characterised in that the ratchet is fixedly connected to the outer wall of the second base pipe by a third shear pin (29), the second base pipe being adapted to shear the third shear pin under unseating pressure to cause the slip sleeve to descend relative to the second base pipe and to retract the slips to complete the unseating.