Annulus plugging device and using method thereof

Abstract

The invention discloses an annulus plugging device and a using method thereof. The plugging device comprises an upper connector, a center pipe and a lower connector which are connected, and an annulus plugging assembly, a first thrust assembly, a second thrust assembly and an anchoring assembly which are sequentially connected to the center pipe in a sleeving mode. The annulus plugging assembly comprises at least two rubber sleeve sealing assemblies and a metal sealing assembly arranged between every two adjacent rubber sleeve sealing assemblies, and the two ends of each metal sealing assembly abut against the corresponding rubber sleeve sealing assembly. The anchoring assembly comprises a taper sleeve and a slip sleeve matched with the taper sleeve, and one end of the slip sleeve is slidably arranged on the taper sleeve in a sleeving mode. In the state of pressure building in the central pipe, the first thrust assembly pushes the rubber sleeve sealing assembly to expand in the radial direction and drives the metal sealing assembly to expand in the radial direction so as to seal an annular space between the central pipe and an external sleeve; the second pushing assembly pushes the taper sleeve to move in the axial direction so that the slip sleeve can expand in the radial direction and be embedded into the casing pipe. The wellbore annulus plugging capacity can be improved, and the annulus pressure risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas cementing tools, and particularly to an annulus plugging device and a method for using the same. Background Art

[0002] The problem of annulus pressure has always been a technical problem that plagues the safe production of gas storage reservoirs and gas wells. At present, most oilfields mainly use packer technology in combination with cementing cement rings to plug and improve the annulus plugging ability, so as to reduce the risk of annulus pressure. The commonly used existing packers are mainly hydraulic expansion packers, compression packers, and oil / water self-expanding packers. Summary of the Invention

[0003] The inventors of the present application found that the existing hydraulic expansion packers and compression packers have insufficient packing ability and are greatly affected by the vibration of the pipe string, resulting in a high risk of seal failure of the rubber cylinder; while the existing oil / water self-expanding packers can only seal the first cementing surface of the cementing cement ring, and also have poor packing ability.

[0004] In view of the above problems, embodiments of the present invention are proposed to provide an annulus plugging device and a method for using the same that overcome the above problems or at least partially solve the above problems.

[0005] Embodiments of the present invention provide an annulus plugging device, including: an upper joint, a central tube, a lower joint connected in sequence, and an annulus plugging assembly, a first thrust assembly, a second thrust assembly, and an anchoring assembly sleeved on the central tube in sequence;

[0006] The annulus plugging assembly includes: at least two rubber cylinder sealing assemblies and a metal sealing assembly disposed between adjacent two rubber cylinder sealing assemblies, and both ends of the metal sealing assembly are respectively abutted against the rubber cylinder sealing assemblies;

[0007] The anchoring assembly includes a cone sleeve and a slip sleeve adapted to the cone sleeve, and one end of the slip sleeve is slidably sleeved on the cone sleeve;

[0008] Under the state of pressure buildup in the central tube:

[0009] The first thrust assembly pushes the rubber cylinder sealing assembly to expand radially, and drives the metal sealing assembly to expand radially to seal the annulus between the central tube and the external casing; and the second thrust assembly pushes the cone sleeve to move axially, so that the slip sleeve expands radially and embeds into the casing.

[0010] In an optional embodiment, the rubber cylinder sealing assembly includes: a rubber cylinder and first protective sleeves disposed at both ends of the rubber cylinder;

[0011] The metal sealing assembly includes: two symmetrically arranged metal sealing rings, with one end face of the metal sealing ring in abutment and an inner hole adapted to the shape of the first protective sleeve provided at the other end for abutting against the first protective sleeve through the inner hole.

[0012] In an alternative embodiment, the barrel of the rubber cylinder is of a cylindrical structure with conical structures at both ends; the first protective sleeve includes: a first abutting portion abutting against the outer surface of the conical structure of the rubber cylinder and a second abutting portion abutting against a part of the outer surface of the cylindrical structure;

[0013] The metal sealing ring includes: a cylindrical section and a conical section, with the large-diameter end of the cylindrical section connected to the conical section and the two being transitioned by an arc, and adjacent metal sealing rings abutting against each other through the end face of the small-diameter end of the conical section; and the inner hole at one end of the cylindrical section of the metal sealing ring fits with the first abutting portion.

[0014] In an alternative embodiment, an annular groove is provided on the inner wall of the metal sealing ring, and a plurality of sealing bodies are arranged in the annular groove to seal the metal sealing ring and the central pipe, and a spacer ring is arranged between adjacent sealing bodies.

[0015] In an alternative embodiment, the sealing body includes: a plurality of metal sealing rings and a plurality of rubber sealing rings, and the metal sealing rings and rubber sealing rings are arranged alternately.

[0016] In an alternative embodiment, the first protective sleeve is a metal protective sleeve with a ductility greater than that of 45# steel; silver plating layers are provided on the end faces where the metal sealing rings abut against each other and on the outer surface of the metal sealing rings.

[0017] In an alternative embodiment, the annulus plugging device of the embodiment of the present invention further includes: a self-expanding sealing assembly slidably sleeved on the central pipe;

[0018] The self-expanding sealing assembly is arranged between the second thrust assembly and the anchoring assembly, and the self-expanding sealing assembly can expand in an oil-encountering or water-encountering state.

[0019] In an alternative embodiment, the self-expanding sealing assembly includes: a matrix, self-expanding rubber, and a second protective sleeve; a plurality of through holes are provided on the matrix, the self-expanding rubber is located on the inner surface, outer surface, and through holes of the matrix, and the second protective sleeve is arranged at both ends of the self-expanding rubber.

[0020] In an alternative embodiment, the annulus plugging device of the embodiment of the present invention further includes: a connecting sleeve arranged between the first thrust assembly and the second thrust assembly, and a plug arranged on the central pipe, and a sealing ring is arranged between the plug and the central pipe;

[0021] The connecting sleeve is sleeved on the central tube, and a first diversion groove is provided on the connecting sleeve;

[0022] The plug is used to connect the central flow channel of the central tube and the first diversion groove of the connecting sleeve after the pressure in the tube reaches a preset pressure, so that the hydraulic pressure acts on the first thrust assembly and the second assembly through the first diversion groove.

[0023] In an optional embodiment, a limiting assembly may further be provided between the first thrust assembly and the connecting sleeve;

[0024] The limiting assembly includes an open lock ring, the open lock ring is sleeved in the groove of the central tube, and is connected to the central tube through a screw and a fixing ring, and a second diversion groove communicating with the first diversion groove is provided on the open lock ring.

[0025] In an optional embodiment, the plug includes: an upper base body, a lower base body and a rupture plate arranged between the upper base body and the lower base body;

[0026] The upper base body is provided with a first through hole communicating with the central flow channel, the lower base body is provided with a second through hole communicating with the diversion groove, and the rupture plate can rupture under a preset pressure to connect the first through hole and the second through hole.

[0027] In an optional embodiment, the first pushing assembly includes: a spacer ring, an upper push sleeve and an upper piston sequentially sleeved on the central tube, and an upper cylinder sleeve sleeved outside the upper push sleeve and the upper piston;

[0028] One end of the upper push sleeve abuts against the spacer ring and is connected to the upper push sleeve through an upper shear pin, and the other end is connected to the connecting sleeve; an upper lock ring is further sleeved on the upper piston, the upper lock ring is provided with a first reverse tooth, and the upper cylinder sleeve is provided with a second reverse tooth adapted to the first reverse tooth;

[0029] The second pushing assembly includes: a lower piston and a lower push sleeve sequentially sleeved on the central tube, and a lower cylinder sleeve sleeved outside the lower push sleeve and the lower piston;

[0030] One end of the upper cylinder sleeve is connected to the connecting sleeve, the other end is connected to the base body of the self-expanding sealing assembly, and is connected to the lower push sleeve through a lower shear pin; a lower lock ring is further sleeved on the lower piston, the lower lock ring is provided with a third reverse tooth, and the lower cylinder sleeve is provided with a fourth reverse tooth adapted to the third reverse tooth.

[0031] In an optional embodiment, the tapered sleeve includes a first body and a plurality of cone assemblies arranged on the first body, and the cone assemblies are arranged at intervals along the axial direction;

[0032] The cone assembly includes a plurality of cones arranged circumferentially along the body, and the cones of adjacent cone assemblies are arranged staggeredly in the circumferential direction;

[0033] The cone includes: two side baffles and an inclined surface structure arranged between the side baffles;

[0034] Correspondingly, the slip sleeve includes a second body and a plurality of slips connected to the second body. The slips are arranged corresponding to the cones and are mutually attached through the inclined surface structure.

[0035] In an alternative embodiment, one end of the slip sleeve close to the lower sub is connected to the lower sub through a compression cap, and the compression cap and the lower sub are connected through a shear ring.

[0036] Based on the same inventive concept, an embodiment of the present invention further provides a method for using the above-mentioned annulus packer, which is characterized by including:

[0037] Apply pressure inside the pipe. When the pressure reaches the preset pressure, the first thrust assembly pushes the rubber barrel seal assembly to expand radially and drives the metal seal assembly to expand radially to seal the annulus between the central pipe and the external casing; and the second push assembly pushes the cone sleeve to move axially, so that the slip sleeve expands radially and is embedded in the casing.

[0038] In an alternative embodiment, the method for using the annulus packer according to the embodiment of the present invention further includes:

[0039] In the pre-set hanging state of the packer, pull up the central pipe to drive the lower sub to move axially to cut the shear ring, and then the slip sleeve moves axially downward to achieve release of the stuck.

[0040] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:

[0041] The annulus packer provided by the embodiment of the present invention is provided with an annulus sealing assembly and an anchoring assembly. Among them, the annulus sealing assembly includes a rubber barrel seal assembly and a metal seal assembly. Under the state of applying pressure inside the central pipe, the first thrust assembly can push the rubber barrel seal assembly to expand radially and drive the metal seal assembly to expand radially to seal the annulus between the central pipe and the external casing. That is, under the state of applying pressure inside the pipe, the annulus between the central pipe and the external casing of the packer provided by the embodiment of the present invention is sealed by two methods of metal seal and rubber barrel seal, which can improve the sealing effect; and under the state of applying pressure inside the pipe, the second push assembly pushes the cone sleeve to move axially, so that the slip sleeve expands radially and is embedded in the casing, which can reduce the occurrence of the situation that the annulus sealing assembly fails to seal due to the vibration of the pipe string, further improves the annulus sealing ability, and reduces the risk of pressure in the pipe annulus.

[0042] Other features and advantages of the present invention will be described in the following specification, and partly will become obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the written specification, claims, and drawings.

[0043] The technical solutions of the present invention will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0044] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0045] Figure 1 is a schematic structural view of the annulus plugging device in the embodiment of the present invention;

[0046] Figure 2 is a schematic structural view of the annulus sealing assembly in the embodiment of the present invention;

[0047] Figure 3 is a schematic structural view of the metal sealing assembly in the embodiment of the present invention;

[0048] Figure 4 is a schematic structural view of the self-expanding sealing assembly in the embodiment of the present invention;

[0049] Figure 5 is a schematic structural view of the plug in the embodiment of the present invention;

[0050] Figure 6 is a schematic structural view of the locking ring in the embodiment of the present invention;

[0051] Figure 7 is a schematic structural view of the open locking ring in the embodiment of the present invention;

[0052] Figure 8 is a schematic structural view of the anchoring assembly in the embodiment of the present invention.

[0053] Description of the Reference Numerals:

[0054] 1. Upper connector; 2. Central tube; 3. Rubber barrel seal assembly; 4. Metal seal assembly; 5. Spacer ring; 6. Upper shear pin; 7. Upper push sleeve; 8. Upper cylinder sleeve; 9. Upper locking ring; 10. Upper piston; 11. Split locking ring; 12. Fixed ring; 13. Connecting sleeve; 14. Plug; 15. Lower cylinder sleeve; 16. Lower piston; 17. Lower locking ring; 18. Lower push sleeve; 19. Lower shear pin; 20. Self-expanding seal assembly; 21. Tapered sleeve; 22. Slip sleeve; 23. Compression cap; 24. Set screw; 25. Shear ring; 26. Lower connector

[0055] 31. First protective sleeve; 32. Rubber barrel; 41. Metal seal ring; 42. Silver plating; 43. Gasket ring; 44. Metal sealing ring; 45. Inner surface; 46. Rubber sealing ring

[0056] 111. Second flow guide groove; 141. Lower base; 142. Sealing ring; 143. Rupture plate; 144. Upper base; 145. First through hole; 146. Second through hole; 201. Connecting thread; 202. Second protective sleeve; 203. Self-expanding rubber; 211. Upper cone; 212. Lower cone; 213. First body; 221. Long-arm slip; 222. Short-arm slip; 223. Second body Detailed implementation manners

[0057] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0058] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "central", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0059] In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] In order to solve the problems existing in the prior art, an embodiment of the present invention provides an annulus plugging device and a using method thereof to improve the annulus plugging ability of a gas well borehole and reduce the risk of annulus pressure. It should be noted that in the embodiment of the present invention, the end close to the wellhead during the lowering process of the annulus plugging device is called the upper end, and the end far from the wellhead is called the lower end.

[0061] An embodiment of the present invention provides an annulus plugging device, as shown in Figure 1 which includes: an upper sub 1, a central tube 2, a lower sub 26 connected in sequence, and an annulus plugging assembly, a first thrust assembly, a second thrust assembly, and an anchoring assembly sleeved on the central tube 2 in sequence;

[0062] The annulus plugging assembly includes: at least two rubber barrel sealing assemblies 3 and a metal sealing assembly 4 arranged between two adjacent rubber barrel sealing assemblies 3, and both ends of the metal sealing assembly 4 are respectively in contact with the rubber barrel assembly 3;

[0063] The anchoring assembly includes a cone sleeve 21 and a slip sleeve 22 adapted to the cone sleeve 21, and one end of the slip sleeve 22 is slidably sleeved on the cone sleeve 21;

[0064] In the state of building pressure inside the central tube 2:

[0065] The first thrust assembly pushes the rubber barrel sealing assembly 3 to expand radially and drives the metal sealing assembly 4 to expand radially to seal the annulus between the central tube 2 and the external casing; and the second thrust assembly pushes the cone sleeve 21 to move axially so that the slip sleeve 22 expands radially and embeds into the casing.

[0066] The annular plugging device provided by the embodiment of the present invention is provided with an annular plugging assembly and an anchoring assembly. Among them, the annular plugging assembly includes a rubber barrel sealing assembly 3 and a metal sealing assembly 4. Under the state of pressure buildup inside the central pipe 2, the first thrust assembly can push the rubber barrel sealing assembly 3 to expand radially and drive the metal sealing assembly 4 to expand radially to seal the annulus between the central pipe 2 and the external casing. That is, under the state of pressure buildup inside the pipe, the annulus between the central pipe 2 and the external casing of the plugging device provided by the embodiment of the present invention is sealed by two methods: metal sealing and rubber barrel 32 sealing, which can improve the sealing effect; and under the state of pressure buildup inside the pipe, the second pushing assembly pushes the cone sleeve 21 to move axially, so that the slip sleeve 22 expands radially and is embedded in the casing, which can reduce the occurrence of the sealing failure of the annular plugging assembly caused by the vibration of the pipe string, further improve the annular plugging ability, and reduce the risk of pressure in the pipeline annulus.

[0067] Among them, the upper sub 1, the central pipe 2 and the lower sub 26 can be specifically connected together by casing threads. The upper sub 1 and the lower sub 26 are respectively used to connect the upper pipe string and the lower pipe string, and the upper end of the rubber barrel sealing assembly 3 is limited by the end face of the upper sub 1.

[0068] In an alternative embodiment, referring to Figure 2 as shown, the rubber barrel sealing assembly 3 includes: a rubber barrel 32 and first protective sleeves 31 arranged at both ends of the rubber barrel 32;

[0069] The metal sealing assembly 4 includes: two metal sealing rings 41 symmetrically arranged, and one end face of the metal sealing ring 41 abuts against each other, and the other end is provided with an inner hole adapted to the shape of the first protective sleeve 31 to abut against the first protective sleeve 31 through the inner hole.

[0070] Furthermore, the rubber barrel 32 is sleeved on the central pipe 2. Among them, referring to Figure 2 as shown, the barrel of the rubber barrel 32 is a cylindrical structure, and both ends are conical structures, and the obtuse angle of the conical structure of the rubber barrel 32 is transitioned by an arc;

[0071] The first protective sleeve 31 is a thin-wall flat arch structure, including: a first abutting portion abutting against the outer surface of the conical structure of the rubber barrel 32 and a second abutting portion abutting against a part of the outer surface of the cylindrical structure;

[0072] The metal sealing ring 41 includes: a cylindrical section and a conical section. The cylindrical section is connected to the large-diameter end of the conical section, and the two are transitioned by an arc. The adjacent metal sealing rings 41 abut against each other through the end face of the small-diameter end of the conical section; and the inner hole at one end of the cylindrical section of the metal sealing ring 41 fits with the first abutting portion. That is, the cross-section of the metal sealing ring 41 is semi-Y-shaped; since the metal sealing assembly 4 is composed of metal sealing rings 41 symmetrically distributed between two groups of rubber barrel sealing assemblies 3, the cross-section of the metal sealing assembly 4 is a Y-shaped structure.

[0073] Optionally, the first protective sleeve 31 and the rubber cylinder 32 can be an integrated structure processed by vulcanization process, or a structure connected together after being processed separately. The embodiments of the present invention do not make specific limitations on this.

[0074] Among them, the first protective sleeve 31 is a metal protective sleeve and has a ductile structure, and its ductility can be greater than that of 45# steel to avoid breakage when the first protective sleeve 31 expands radially together with the rubber cylinder 32 and lose the protective effect on the rubber cylinder 32.

[0075] Furthermore, silver coatings 42 are provided on the end faces where the metal sealing rings 41 abut against each other and on the outer surfaces of the metal sealing rings 41. Specifically, silver coatings 42 are provided on the end faces where the metal sealing rings 41 abut against each other, on the outer surfaces of the cylindrical sections of the metal sealing rings 41, on the outer surfaces of the transition sections, and on the outer surfaces of at least part of the conical sections. The provision of the silver coatings 42 can increase the sealing effect between the metal sealing rings 41 and the casing, and between two adjacent metal sealing rings 41; when the rubber cylinder 32 sealing assembly is squeezed and deformed, the compressed rubber cylinder 32 forces the two branches of the Y-shaped metal sealing assembly 4 to expand outwards, and the silver-coated areas on the outer surfaces of the cylindrical section and the transition section are closely attached to the outer casing to achieve metal sealing; and the silver-coated areas on the inner surfaces 45 of the two groups of metal sealing rings 41 are squeezed and attached to achieve metal sealing.

[0076] In an optional embodiment, referring to Figure 3 As shown, annular grooves are provided on the inner walls of the metal sealing rings 41, and a plurality of sealing bodies are provided in the annular grooves to seal the metal sealing rings 41 and the central pipe 2, and spacer rings 43 are provided between adjacent sealing bodies. The provided sealing bodies can enhance the sealing effect of the metal sealing rings 41 and can prevent oil, water, and gas from flowing through the gap between the metal sealing rings 41 and the central pipe 2 when the inner surfaces 45 where the metal sealing rings 41 abut against each other are sealed and fail, so as to keep the annulus under pressure.

[0077] Optionally, the seal body in the embodiments of the present invention may be entirely a metal sealing ring 44, entirely a rubber sealing ring 46, or in a form including a metal sealing ring 44 and a rubber sealing ring 46; preferably, the seal body disposed within the metal sealing ring 41 includes: a plurality of metal sealing rings 44 and a plurality of rubber sealing rings 46, and the metal sealing rings 44 and the rubber sealing rings 46 are alternately arranged; the seal body being arranged in a form including a metal sealing ring 44 and a rubber sealing ring 46 can function to seal both gas and fluid, further improving the sealing effect between the central tube 2 and the metal sealing ring 41; and it can avoid the situation where gas sealing cannot be achieved when only a rubber sealing ring 46 is provided, and the problem that when only a metal sealing ring 44 is provided, the deformation amount of the metal sealing ring 44 is small when the extrusion force is insufficient, thereby resulting in a poor sealing effect. Among them, the specific number of the metal sealing rings 44 and the rubber sealing rings 46 can be designed according to actual needs, and the embodiments of the present invention do not make specific limitations thereon; referring to Figure 2 As shown, taking the setting of two metal sealing rings 44 and one rubber sealing ring as an example, the description is as follows: the combination mode of the spacer ring 43, the metal sealing ring 44, and the rubber sealing ring 46 is spacer ring 43 + metal sealing ring 44 + spacer ring 43 + rubber sealing ring 46 + spacer ring 43 + metal sealing ring 44 + spacer ring 43, and the openings of the two groups of metal sealing rings 44 are installed back to back; among them, the structure of the metal sealing ring 44 is as follows, its outer shell section is C-shaped and silver-plated, and an annular spring is wrapped inside, and specifically, it can be but is not limited to a spring-enhanced metal sealing ring 44.

[0078] In an optional embodiment, the annulus plug provided in the embodiments of the present invention further includes: a self-expanding sealing assembly 20 slidably sleeved on the central tube 2;

[0079] The self-expanding sealing assembly 20 is disposed between the second thrust assembly and the anchoring assembly, and the self-expanding sealing assembly 20 can expand in an oil-encountering or water-encountering state to perform sealing compensation on the first cementing surface between the annulus plug and the external cement sheath.

[0080] Among them, referring to Figure 4As shown, the self-expanding sealing assembly includes: a matrix, a self-expanding rubber 203, and a second protective sleeve 202; a plurality of through holes are provided on the matrix, the self-expanding rubber 203 is located on the inner surface, outer surface and through holes of the matrix, and the second protective sleeve 202 is provided at both ends of the self-expanding rubber 203. Optionally, connection threads 201 are provided at both ends of the matrix, the through holes are evenly distributed in the middle of the matrix, and the matrix, the self-expanding rubber 203, and the second protective sleeve 202 are integrally formed by vulcanization process, and a certain thickness of self-expanding rubber 203 is left on both the inner and outer surfaces of the matrix. Among them, the self-expanding rubber can expand when encountering oil or water. During the process of the annulus plugging device entering the well and cementing, the self-expanding rubber 203 of the self-expanding sealing assembly 20 does not expand or only expands slightly, and absorbs the water in the cement slurry during the cement setting process to complete the sealing between the first cementing surface of the cement sheath. In the later stage, when oil and gas gush up after micro-cracks appear on the first cementing surface of the cement sheath due to vibration or other factors, it can absorb oil, gas and water and expand again to complete the crack sealing. Therefore, setting the self-expanding sealing assembly 20 can play a role in sealing compensation and further improve the annulus plugging effect.

[0081] Optionally, referring to Figure 1 As shown, the annulus plugging device provided by the embodiment of the present invention further includes: a connecting sleeve 13 provided between the first thrust assembly and the second thrust assembly, and a plug 14 provided on the central tube 2, and a sealing ring 142 is provided between the plug 14 and the central tube 2;

[0082] The connecting sleeve 13 is sleeved on the central tube 2, and a first diversion groove is provided on the connecting sleeve 13;

[0083] The plug 14 is used to connect the central flow channel of the central tube 2 and the first diversion groove of the connecting sleeve 13 after the pressure in the pipe reaches a preset pressure, so that the hydraulic pressure acts on the first thrust assembly and the second assembly through the first diversion groove.

[0084] In an alternative embodiment, referring to Figure 5 As shown, the plug 14 includes: an upper matrix 144, a lower matrix 141, and a rupture plate 143 provided between the upper matrix 144 and the lower matrix 141;

[0085] The upper matrix 144 is provided with a first through hole 145 communicating with the central flow channel, the lower matrix 141 is provided with a second through hole 146 communicating with the diversion groove, and the rupture plate 143 can rupture under a preset pressure to communicate the first through hole 145 and the second through hole 146; wherein, the rupture plate 143 can be welded between the upper matrix 144 and the lower matrix 141, and the rupture plate 143 can be a bursting disc that can be penetrated under a certain pressure difference.

[0086] Specifically, the first flow guiding groove includes: a groove provided on the outer wall of the connecting sleeve 13, and keyway-shaped flow guiding grooves provided on the contact surface between the connecting sleeve 13 and the central tube 2 and evenly distributed along the circumference, wherein the groove is correspondingly communicated with the second through hole 146; preferably, the groove is provided at the middle position of the connecting sleeve 13, and the axis of the plug 14 mounting hole is perpendicular to the axis of the central tube 2 and aligned with the central plane of the connecting sleeve 13.

[0087] The plug 14 of the embodiment of the present invention will only rupture when the hydraulic pressure reaches the preset pressure. Compared with the existing plug 14 provided with a single opening rod, it can avoid the situation that the plugging device is pre-set in the case of falling objects in the wellbore and the like.

[0088] Optionally, for the annular plugging device provided by the embodiment of the present invention, a limiting component may also be provided between the first thrust component and the connecting sleeve 13;

[0089] The limiting component includes an open lock ring 11. The open lock ring 11 is sleeved in the groove of the central tube 2, connected to the central tube 2 through screws and a fixing ring 12, and a second flow guiding groove 111 communicated with the first flow guiding groove is provided on the open lock ring 11.

[0090] Specifically, referring to Figure 7 As shown, the open lock ring 11 has a break opening and circumferentially evenly distributed second flow guiding grooves 111. It is installed in the card slot of the central tube 2. The inner diameter of the open lock ring 11 can be the same as the inner diameter of the card slot, and the outer diameter and the diameter of the second flow guiding grooves 111 are larger than the outer diameter of the central tube 2 to prevent the high-pressure fluid in the first flow guiding groove from not flowing into the second flow guiding groove 111 and acting on the second thrust component; further, the fixing ring 12 is designed with a plurality of uniformly distributed threaded holes, and its inner diameter is slightly larger than the outer diameter of the open lock ring 11 to be sleeved outside the open lock ring 11, and the fixing ring 12 and the open lock ring 11 are fixed on the central tube 2 through screws to form a limiting mechanism; the upper end surface of the connecting sleeve 13 fits with the lower end of the limiting mechanism composed of the fixing ring 12 and the open lock ring 11 to limit the axial upward movement of the connecting sleeve 13.

[0091] Optionally, the first pushing component includes: a spacer ring 5, an upper pushing sleeve 7 and an upper piston 10 sequentially sleeved on the central tube 2, and an upper cylinder sleeve 8 sleeved outside the upper pushing sleeve 7 and the upper piston 10;

[0092] One end of the upper pushing sleeve 7 abuts against the spacer ring 5 and is connected to the upper pushing sleeve 7 through an upper shear pin 6, and the other end is connected to the connecting sleeve 13; a locking ring 9 is also sleeved on the upper piston 10. The locking ring 9 is provided with first reverse teeth, and the upper cylinder sleeve 8 is provided with second reverse teeth adapted to the first reverse teeth;

[0093] The second pushing component includes: a lower piston 16 and a lower pushing sleeve 18 sequentially sleeved on the central tube 2, and a lower cylinder sleeve 15 sleeved outside the lower pushing sleeve 18 and the lower piston 16;

[0094] One end of the upper cylinder liner 8 is connected to the connecting sleeve 13, the other end is connected to the matrix of the self-expanding seal assembly, and is connected to the lower push sleeve 18 through the lower shear pin 19; a lower locking ring 17 is also sleeved on the lower piston 16, the lower locking ring 17 is provided with third reverse teeth, and the lower cylinder liner 15 is provided with fourth reverse teeth adapted to the third reverse teeth.

[0095] Specifically, referring to Figure 1 As shown, the upper piston 10 is a stepped annular boss with a sealing ring and a connecting thread 201, and is sealed with the central tube 2 and the upper cylinder liner 8 through a sealing ring. It is specifically installed at the upper end of the opening locking ring 11 and the fixing ring 12 in the axial direction, and the downward movement in the axial direction is restricted by a limiting component at the lower end; referring to Figure 6 As shown, the upper locking ring 9 is a C-shaped opening ring with a conical surface and serrated reverse teeth. Its inner diameter is larger than the diameter of the stepped surface that cooperates with the upper piston 10, and it is sleeved on the stepped surface at the lower end of the thread of the upper piston 10; the upper push sleeve 7 is designed with a conical surface whose conical angle is the same as that of the conical surface of the upper locking ring 9, and the upper push sleeve 7 and the upper piston 10 are connected together by a thread. The lower end of the upper cylinder liner 8 is connected to the connecting sleeve 13 by a thread and is sealed by a sealing ring 142. The upper end is fixed to the upper push sleeve 7 through an upper shear pin 6. The upper cylinder liner 8 is designed with serrated reverse teeth that are the same as the tooth shape of the upper locking ring 9.

[0096] It should be noted that the structures of the lower piston 16, the lower push sleeve 18, the lower cylinder liner 15, the lower shear pin 19, and the lower locking ring 17 included in the second thrust assembly are respectively similar to the structures of the upper piston 10, the upper push sleeve 7, the upper cylinder liner 8, the upper shear pin 6, and the upper locking ring 9 of the first thrust assembly. The assembly and combination methods of each component are the same. The difference is that the lower end of the lower push sleeve 18 is designed with a thread structure connected to the self-expanding seal assembly 20. Therefore, the specific structures of the components of the second thrust assembly in the embodiments of the present invention will not be elaborated in detail.

[0097] Optionally, in the anchoring assembly, referring to Figure 8 As shown, the tapered sleeve 21 includes a first body 213 and a plurality of tapered body assemblies arranged on the first body 213. The tapered body assemblies are arranged at intervals along the axial direction;

[0098] The tapered body assembly includes a plurality of tapered bodies (211, 212) arranged circumferentially on the first body 213, and the tapered bodies of adjacent tapered body assemblies are staggered circumferentially;

[0099] The tapered body includes: two side baffles and an inclined surface structure arranged between the side baffles;

[0100] Correspondingly, the slip sleeve 22 includes a second body 223 and a plurality of slips (221, 222) connected to the second body 223. The slips are arranged corresponding to the tapered bodies and are mutually attached through the inclined surface structure.

[0101] It should be noted that the embodiments of the present invention do not specifically limit the number of cone assemblies provided on the cone sleeve 21, the number of cones included in each cone assembly, etc. For example, in an alternative embodiment, referring to Figure 8 As shown, the cone sleeve 21 includes two sets of cones (211, 212) arranged up and down. Each set of cones is composed of 4 sets of evenly distributed independent cones; the two sets of cones are axially spaced apart by a certain distance and circumferentially offset by 45°. Each independent cone includes: side baffles, and a bevel structure is provided between the two side baffles, and the outer surface of the side baffle is a combination of a cylindrical surface and a conical surface. Correspondingly, the slip sleeve 22 is composed of 4 sets of circumferentially evenly distributed long-arm slips 221, 4 sets of circumferentially evenly distributed short-arm slips and connecting threads 201. There is a certain axial distance and a circumferential interval of 45° between adjacent long-arm slips 221 and short-arm slips 222. The slip teeth of each set of slips are evenly distributed, and the long-arm slips cooperate with the upper cones of the cone sleeve 21 one by one, and the short-arm slips 222 cooperate with the lower cones of the cone sleeve 21 one by one. Each slip bevel is completely attached to the bevel of the cone sleeve 21, and the two side baffles of the cone can prevent the slip sleeve 22 from rotating.

[0102] Under the condition of internal pressure buildup in the central pipe 2, under the action of the second thrust assembly, relative movement occurs between the slip sleeve 22 and the cone sleeve 21, and the slips expand outward along the slope on the cone sleeve 21. The slip teeth on the slip sleeve are used to bite with the outer casing. When the pipe string vibrates, the annulus packer is not affected by the vibration, and the combination of the length and axial spacing of the slips can disperse the anchoring force while increasing the anchoring force to the upper and lower parts of the outer casing, avoiding damage to the outer casing caused by a plurality of single slips evenly distributed in the circumferential direction.

[0103] Furthermore, for the annulus packer of the embodiments of the present invention, one end of the slip sleeve 22 close to the lower sub 26 is connected to the lower sub 26 through a compression cap 23, and a shear ring 25 is connected between the compression cap 23 and the lower sub 26.

[0104] Specifically, the compression cap 23 is threadedly connected to the slip sleeve 22 and fixed by a setscrew 24. The shear ring 25 can be an open structure, installed in the slot of the lower sub 26 and fixed by the compression cap 23 and the slip sleeve 22; referring to Figure 1 As shown, after the components of the annulus packer are assembled, the lower end face of the first body of the cone sleeve 21 is spaced from the upper step face of the second body of the slip sleeve 22 by a distance L1, the lower inner step face of the second body of the slip sleeve 22 is spaced from the upper end face of the lower sub 26 by a distance L2, and the lower end face of the compression cap 23 is spaced from the upper step face of the lower sub 26 by a distance L3. Among them, L1 should be greater than the stroke of the cone sleeve 21 for the slips to bite with the outer casing. L2 and L3 are greater than the stroke required for the slips to release.

[0105] The annulus plugger provided by the embodiment of the present invention has an annulus plugging component, a self-expanding sealing component 20 and an anchoring component whose activation is jointly controlled by the plug 14 and the upper and lower shear pins 19; after the pressure inside the central tube 2 reaches the breakdown pressure of the rupture plate 143 of the plug 14, the high-pressure liquid flows through the first through hole 145 and the second through hole 146 of the plug 14 through the first guide groove of the connecting sleeve 13, and after passing through the first guide groove, the upper end flows through the second guide groove 111 of the open locking ring 11 to apply pressure to the end face of the upper piston 10, driving the upper push sleeve 7 to shear off the upper shear pin 6, and further driving the upper locking ring 9 to move axially upward, pushing the spacer ring 5 to extrude the annulus plugging component, and the rubber sleeve 32 sealing component is gradually squeezed to expand outward and fit with the outer casing to achieve sealing and plugging between the rubber sleeve 32 and the central tube 2 and the outer casing. While the rubber cylinder 32 sealing assembly is extruded and deformed, the compression rubber cylinder 32 forces the two branches of the Y-shaped metal sealing assembly 4 to expand outward, and the silver-plated area of ​​the Y-shaped branch of the metal sealing ring 41 is tightly fitted with the outer sleeve to achieve metal sealing; further, the silver-plated areas of the inner surface 45 of the two sets of expandable metal sealing rings 41 are squeezed and fitted to achieve metal sealing; and the metal sealing ring 44 and rubber sealing ring 46 arranged in the annular groove of the metal sealing ring 41 play the role of metal sealing and rubber sealing at the same time, and the upper locking ring 9 and the reverse tooth stop mechanism of the upper cylinder sleeve 8 are meshed; after the pressure load of the setting seal is released, the upper push sleeve 7 is reversely stressed, and the upper locking ring 9 is opened by the cone surface, and the reverse tooth mechanism is locked, and the annular space plugging assembly cannot be unsealed. While the upper end is subjected to the setting seal pressure load, the high-pressure fluid acts on the lower piston 16 through the first guide groove at the lower end of the connecting sleeve 13, and further pushes the lower push sleeve 18, the self-expanding sealing assembly 20, and the cone sleeve 21 to move axially downward. The slip sleeve 22 moves relative to the cone sleeve 21, and the slip expands outward along the slope on the cone sleeve 21, and the slip teeth are engaged with the outer casing. When the pipe string vibrates, the annulus plugger is not affected by the vibration. The length combination and axial spacing combination of the slip can disperse the anchoring force in the upper and lower parts of the outer casing while improving the anchoring force, avoiding the damage of multiple single slips evenly distributed around the circumference to the outer casing. At the same time, the lower lock ring 17 and the lower cylinder sleeve 15 reverse tooth mechanism complete the meshing and locking to prevent the slip from being unstuck.

[0106] Furthermore, after cementing is completed, the self-expanding rubber on the self-expanding sealing assembly 20 can realize the self-expanding function. When oil and gas rise after micro-cracks appear in the cement ring due to vibration or other factors, it can absorb oil, gas and water to automatically expand and complete the crack plugging. When the annulus plugger is prematurely seated during the well entry process, the central pipe 2 can be pulled axially by lifting the pipe string, driving the lower joint 26 to cut the shear ring 25, and the slip is reset and unstuck.

[0107] The annular blowout preventer in the embodiments of the present invention mainly includes: an annular blowout prevention assembly, a self-expanding sealing assembly, and an anchoring assembly. The annular blowout prevention assembly includes two methods of expanding and sealing by compressing the rubber cylinder 32 and extruding metal seals. The sealing between the annular blowout preventer in the embodiments of the present invention and the outer casing is achieved by the hydraulic mechanism pushing the rubber cylinder sealing assembly and the metal sealing assembly 4 to deform, and the sealing between the central pipe 2 and the outer casing is realized through rubber-metal sealing and metal-metal sealing, which serves as the main sealing system to achieve high-pressure sealing. The self-expanding sealing assembly can utilize the self-expanding packer mechanism to compensate for the sealing of the first cementing surface. In order to reduce the influence of pipe string vibration on the sealing performance of the blowout preventer, a misaligned anchor claw anchoring assembly is designed to reduce the damage to the outer casing caused by the over-concentration of the anchor claws while achieving anchoring.

[0108] Based on the same inventive concept, the embodiments of the present invention also provide a method for using the above-mentioned annular blowout preventer, including:

[0109] Pressurize the inside of the pipe. When the pressure reaches the preset pressure, the first thrust assembly pushes the rubber cylinder sealing assembly 3 to expand radially, and drives the metal sealing assembly 4 to expand radially to seal the annulus between the central pipe 2 and the external casing; and the second pushing assembly pushes the cone sleeve 21 to move axially, so that the slip sleeve 22 expands radially and embeds into the casing.

[0110] Optionally, the method for using the annular blowout preventer further includes:

[0111] In the state where the blowout preventer is pre-set and hung, pull up the central pipe 2 to drive the lower joint 26 to move axially to cut the shear ring 25, and then the slip sleeve 22 moves downward axially to achieve untying.

[0112] Regarding the method for using the annular blowout preventer in the above embodiments, the specific ways in which each component performs operations have been described in detail in the embodiments related to the annular blowout preventer, and will not be elaborated here in detail. It should be understood that the specific order or hierarchy of the steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of the steps in the process can be rearranged without departing from the protection scope of the present disclosure. The appended method claims list the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy.

[0113] In the foregoing detailed description, various features are combined in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are expressly recited in each claim. Rather, as reflected in the appended claims, the invention lies in less than the full scope of the features of the single disclosed embodiment. Accordingly, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0114] The above description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but one of ordinary skill in the art should recognize that the various embodiments can be further combined and arranged. Accordingly, the embodiments described herein are intended to embrace all such changes, modifications, and variations that fall within the scope of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, this term is inclusive in a manner similar to the term "including", as is explained when "including" is used as a transitional word in a claim. Further, any use of the term "or" in the claims or specification is to be meant "non-exclusive or".

Claims

1. An annulus plugging device, characterized in that: include: An upper joint, a central pipe, a lower joint connected in sequence, and an annulus plugging assembly, a first thrust assembly, a second thrust assembly, and an anchor assembly sleeved on the central pipe in sequence; The annulus plugging assembly comprises: at least two rubber sleeve sealing assemblies and a metal sealing assembly arranged between two adjacent rubber sleeve sealing assemblies, and two ends of the metal sealing assembly are respectively abutted against the rubber sleeve sealing assemblies; The anchor assembly includes a cone sleeve and a slip sleeve adapted to the cone sleeve, and one end of the slip sleeve is slidably sleeved on the cone sleeve; When the center tube is under pressure: The first thrust assembly pushes the rubber sleeve sealing assembly to expand radially, and drives the metal sealing assembly to expand radially to seal the annulus between the center pipe and the outer casing; and the second pushing assembly pushes the cone sleeve to move axially, so that the slip sleeve expands radially and embeds into the casing.

2. The annulus plugging device according to claim 1, characterized in that: The rubber cylinder sealing assembly comprises: a rubber cylinder and a first protective sleeve arranged at both ends of the rubber cylinder; The metal sealing assembly includes: two symmetrically arranged metal sealing rings, one end of which is in abutment with end faces, and the other end is provided with an inner hole adapted to the shape of the first protective sleeve, so as to abut with the first protective sleeve through the inner hole.

3. The annulus plugging device according to claim 2, characterized in that: The body of the rubber cylinder is a cylindrical structure, and both ends are conical structures; the first protective sleeve includes: a first abutting portion abutting against the outer surface of the conical structure of the rubber cylinder, and a second abutting portion abutting against a part of the outer surface of the cylindrical structure; The metal sealing ring comprises: a cylindrical section and a conical section, the cylindrical section is connected to the large diameter end of the conical section, and the two are transitioned by a circular arc, and adjacent metal sealing rings are abutted by the end surface of the small diameter end of the conical section; and the inner hole of one end of the cylindrical section of the metal sealing ring is in contact with the first abutment portion.

4. The annulus plugging device according to claim 2, characterized in that: An annular groove is arranged on the inner wall of the metal sealing ring, a plurality of sealing bodies are arranged in the annular groove to seal the metal sealing ring and the central tube, and gaskets are arranged between adjacent sealing bodies.

5. The annulus plugging device according to claim 4, characterized in that: The sealing body comprises: a plurality of metal sealing rings and a plurality of rubber sealing rings, and the metal sealing rings and the rubber sealing rings are arranged alternately.

6. The annulus plugging device according to claim 3, characterized in that: The first protective sleeve is a metal protective sleeve, and its ductility is greater than that of 45# steel; a silver coating is provided on the end surfaces of the metal sealing rings abutting against each other and on the outer surface of the metal sealing rings.

7. The annulus plugging device according to claim 1, characterized in that: It also includes: a self-expanding sealing assembly slidably sleeved on the central pipe; The self-expanding sealing assembly is disposed between the second thrust assembly and the anchor assembly, and the self-expanding sealing assembly can expand when in contact with oil or water.

8. The annulus plugging device according to claim 7, characterized in that: The self-expanding sealing assembly comprises: a substrate, a self-expanding rubber and a second protective cover; the substrate is provided with a plurality of through holes, the self-expanding rubber is located on the inner surface, the outer surface and the through holes of the substrate, and the second protective cover is provided at both ends of the self-expanding rubber.

9. The annulus plugging device according to claim 7, characterized in that: Also includes: A connecting sleeve arranged between the first thrust assembly and the second thrust assembly, and a plug arranged on the central tube, wherein a sealing ring is arranged between the plug and the central tube; The connecting sleeve is sleeved on the central tube, and a first guide groove is provided on the connecting sleeve; The plug is used to connect the central flow channel of the central pipe with the first guide groove of the connecting sleeve after the pressure in the pipe reaches a preset pressure, so that the hydraulic pressure acts on the first thrust component and the second component through the first guide groove.

10. The annulus plugging device according to claim 9, characterized in that: A limit assembly may also be provided between the first thrust assembly and the connecting sleeve; The limiting assembly includes an open locking ring, which is sleeved in the groove of the central tube and connected to the central tube via screws and a fixing ring, and a second guide groove connected to the first guide groove is provided on the open locking ring.

11. The annulus plugging device according to claim 9, characterized in that: The plug includes: an upper base, a lower base, and a rupture plate arranged between the upper base and the lower base; The upper substrate is provided with a first through hole communicating with the central flow channel, the lower substrate is provided with a second through hole communicating with the guide groove, and the rupture plate can be ruptured under a preset pressure to connect the first through hole with the second through hole.

12. The annulus plugging device according to claim 9, characterized in that: The first pushing assembly comprises: a spacer ring, an upper push sleeve and an upper piston which are sequentially sleeved on the central tube, and an upper cylinder sleeve which is sleeved outside the upper push sleeve and the upper piston; One end of the upper push sleeve abuts against the spacer ring and is sheared The pin is connected to the upper push sleeve, and the other end is connected to the connecting sleeve; the upper piston is also provided with an upper locking ring, the upper locking ring is provided with a first inverted tooth, and the upper cylinder sleeve is provided with a second inverted tooth adapted to the first inverted tooth; The second pushing assembly comprises: a lower piston and a lower pushing sleeve which are sequentially sleeved on the central tube, and a lower cylinder sleeve which is sleeved outside the lower pushing sleeve and the lower piston; One end of the upper cylinder sleeve is connected to the connecting sleeve, and the other end is connected to the base of the self-expanding sealing assembly, and is connected to the lower push sleeve through a lower shear pin; a lower locking ring is also sleeved on the lower piston, and the lower locking ring is provided with a third inverted tooth, and the lower cylinder sleeve is provided with a fourth inverted tooth matched with the third inverted tooth.

13. The annulus plugging device according to claim 1, characterized in that: The cone sleeve comprises a first body and a plurality of cone assemblies arranged on the first body, wherein the cone assemblies are arranged at intervals along the axial direction; The cone assembly includes a plurality of cones arranged along the circumference of the body, and the cones of adjacent cone assemblies are staggered along the circumference; The cone includes: two side baffles and an inclined surface structure arranged between the side baffles; Correspondingly, the slip sleeve includes a second body and a plurality of slips connected to the second body. The slips are arranged corresponding to the cone and fit each other through an inclined structure.

14. The annulus plugging device according to any one of claims 1 to 13, characterized in that: One end of the slip sleeve close to the lower joint is connected to the lower joint through a pressure cap, and the pressure cap and the lower joint are connected through a shear ring.

15. A method for using the annulus plugging device according to any one of claims 1 to 14, characterized in that: include: The pipe is pressurized. When the pressure reaches the preset pressure, the first thrust assembly pushes the rubber sleeve sealing assembly to expand radially, and drives the metal sealing assembly to expand radially, thereby sealing the annulus between the center pipe and the outer casing; and the second thrust assembly pushes the cone sleeve to move axially, thereby causing the slip sleeve to expand radially and embed into the casing.

16. The method of use according to claim 15, characterized in that: Also includes: When the plugger is in the pre-seated state, the central tube is pulled upward to drive the lower joint to move axially to cut off the shear ring, and then the slip sleeve moves axially downward to achieve release.

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