A retrievable and drillable pipe-type isolation mining device

Abstract

A retrieveable and drillable tubing-type wellbore isolation device belongs to the field of oilfield downhole tool technology. This utility model includes, from top to bottom, a tubing assembly, an anchoring and sealing assembly, and a blowout preventer (BOP) bottom valve assembly connected sequentially. The tubing assembly includes a coupling, a protective cap, and a tubing; the outer side of the coupling is threaded to the protective cap, and the inner side is threaded to the upper end of the tubing. The anchoring and sealing assembly includes a central tube, and a setting mechanism, an anchoring mechanism, a sealing mechanism, and a releasing mechanism fitted around the central tube. The BOP bottom valve assembly includes a lower short connector, a BOP sleeve, and a sealing sleeve; the lower short connector is threaded to the sealing sleeve, and the sealing sleeve contains a sealing rubber sleeve. The tubing can be inserted into the anchoring and sealing assembly and the BOP bottom valve assembly, forming a sealing fit with the sealing rubber sleeve. This utility model enables stratified oil production with a single tubing string run, effectively isolates oil layers during pump inspection, and has both retrieveable and drillable retrieval methods, greatly improving operational efficiency and safety.

Description

Technical Field

[0001] This utility model belongs to the field of oilfield downhole tool technology, specifically relating to a retrievable and drillable pipe-insertion isolation production device. Background Technology

[0002] Oilfields are often complex reservoirs with multiple layers, exhibiting significant differences in permeability, crude oil viscosity, and formation pressure among the layers. During combined production, high-pressure, high-permeability layers will preferentially produce fluid and may draw away large amounts of injected water, leading to premature water breakthrough or even flooding and a rapid decline in production capacity. Conversely, low-permeability layers produce less fluid, ultimately resulting in low overall recovery. Layered oil recovery technology is an effective measure to resolve these inter-layer contradictions.

[0003] Currently, there are two main types of stratified oil production tubing used in China: The first type involves direct connection between the tubing, pump, and packer. This type requires removing the packer during pump inspection and replacing it with a new one when re-running the production tubing, resulting in waste. After removal, the upper and lower layers are connected, causing inter-layer interference. Furthermore, in wells with severe corrosion or scaling, packer removal is difficult. The second type uses a double-seal, single-clamp design with a slip-release packer connected to the tubing and then back to the packer. This type has the following problems: if sand production is severe between the two packers, sand can easily bury the packer and tubing, leading to difficult retrieval or even accidents. It also requires two tubing runs: first, running the tubing into the packer for setting and releasing, then retrieving the delivery tubing, and finally running the production tubing, resulting in a complex and costly process.

[0004] Therefore, there is an urgent need for a segregation device that can achieve one-run tubing operation, effectively isolate layers, facilitate pump inspection, and has high retrieval reliability. Utility Model Content

[0005] This invention addresses the aforementioned problems and overcomes the shortcomings of existing technologies by providing a retrievable and drillable tubing-type isolation and extraction device. This invention enables stratified oil extraction with a single tubing run, effectively isolates oil layers during pump inspection, and offers both retrievable and drillable extraction methods, greatly improving operational efficiency and safety.

[0006] To achieve the above objectives, the present invention adopts the following technical solution.

[0007] This utility model provides a retrievable and drillable insert-type isolation mining device, characterized in that it includes an insert assembly, an anchoring and sealing assembly, and a blowout preventer bottom valve assembly connected sequentially from top to bottom; the insert assembly includes a coupling, a protective cap, and an insert, the outer side of the coupling is threaded to the protective cap, and the inner side is threaded to the upper end of the insert; the anchoring and sealing assembly includes a central tube, and a setting mechanism, an anchoring mechanism, a sealing mechanism, and an unsealing mechanism sleeved outside the central tube; the blowout preventer bottom valve assembly includes a lower short joint, a blowout preventer sleeve, and a sealing sleeve; the lower short joint is threaded to the sealing sleeve, and the sealing sleeve is provided with a sealing rubber sleeve; the insert can be inserted into the anchoring and sealing assembly and the blowout preventer bottom valve assembly, and forms a sealing fit with the sealing rubber sleeve.

[0008] Furthermore, the insertion tube assembly also includes a second nut, a second guide shoe, a second connecting sleeve, and an elastic sleeve; the lower end of the insertion tube is threadedly connected to the second nut; the lower end of the second nut is threadedly connected to the second guide shoe; the lower end of the second guide shoe is threadedly connected to the second connecting sleeve; the lower end of the second connecting sleeve is threadedly connected to the elastic sleeve; a small rubber tube, a first positioning cap, a retaining ring, and a second positioning cap are provided on the outside of the second nut; the small rubber tube is provided on the second guide shoe; a ball seat is provided inside the second connecting sleeve, and the ball seat is fixed to the second connecting sleeve by a fourth shear pin; a steel ball is provided inside the ball seat.

[0009] Furthermore, the anchoring mechanism includes a slip cover, a slip, an upper cone, and a lower cone; the slip cover is provided on the outer side of the upper cone and positioned by a shoulder; the slip is provided inside the slip cover, and a slip spring is provided between the slip and the slip cover; the lower end of the slip cover is threadedly connected to a first nut; the lower cone is provided inside the lower end of the slip cover, and the lower cone is positioned by the shoulder of the first nut.

[0010] Furthermore, the sealing mechanism includes a rubber sleeve shaft, a rubber sleeve, an upper pressure ring, and a lower pressure ring; the inner side of the lower cone is threadedly connected to the rubber sleeve shaft, and the outer side is threadedly connected to the upper pressure ring; the rubber sleeve and the lower pressure ring are provided on the outer side of the rubber sleeve shaft; an O-ring is provided on the sealing surface of the rubber sleeve.

[0011] Furthermore, the unsealing mechanism includes a first guide shoe, an unsealing sleeve, a retrieval head, and a protective cone; the first guide shoe is threadedly connected to the unsealing sleeve; a shearing cap is provided inside the first guide shoe and fixed by a first shearing pin; the unsealing sleeve is threadedly connected to the central tube; the retrieval head is provided inside the unsealing sleeve and fixed by a second shearing pin; the lower end of the unsealing sleeve is threadedly connected to the protective cone and the upper cone respectively; sandproof rubber sleeves are provided on the outer sides of the protective cone and the upper cone.

[0012] Furthermore, the setting mechanism includes a main piston, a secondary piston, a first connecting sleeve, and a cylinder liner; the main piston is threadedly connected to the first connecting sleeve; a first locking block is provided inside the main piston, and the main piston and the central tube are positioned by the first locking block; the cylinder liner is provided outside the first connecting sleeve; a second locking spring is provided inside the cylinder liner, and the second locking spring forms a one-way lock with the first connecting sleeve; the lower end of the cylinder liner is threadedly connected to a third nut; the inner side of the third nut is threadedly connected to the lower short connector; the lower short connector is threadedly connected to the central tube; the secondary piston is provided on the lower short connector; the secondary piston and the main piston are fixed by a third shear pin.

[0013] Furthermore, in the blowout preventer assembly, the lower short connector contains the blowout preventer sleeve, which is positioned with the shoulder of the second connecting sleeve; the lower end of the sealing sleeve is threadedly connected to the lower connector.

[0014] Furthermore, the protective cone, the upper cone, the slip, and the slip cover are made of a drillable material.

[0015] The beneficial effects of this utility model.

[0016] This utility model integrates functions: it highly integrates anchoring, sealing, blowout prevention and unsealing functions, so that setting and production can be completed in one trip of tubing, resulting in high work efficiency.

[0017] Reliable interlayer sealing: During pump inspection, as the tubing assembly is removed, the blowout preventer valve automatically closes, while the anchoring seal assembly maintains its seal on the casing, effectively preventing interlayer interference.

[0018] The anchor removal solution is safe and reliable: it offers both retrieval and drilling options. Under normal circumstances, it can be directly unsealed and retrieved using a retrieval head; if obstruction occurs, key anchoring components can be drilled out, greatly reducing operational risks.

[0019] Compact structure and durable anchoring seal: The setting mechanism has a one-way locking function to ensure a long-term effective seal; the connection relationship between each component is clear and the structure is stable.

[0020] High applicability: The device is resistant to high temperature and high pressure, and is especially suitable for complex well conditions such as sand production and scaling. Attached Figure Description

[0021] To make the technical problems solved, the technical solutions, and the beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0022] Figure 1 This is a schematic diagram of the overall half-section structure of this utility model.

[0023] Figure 2 This is a utility model Figure 1 The diagram shows an enlarged view of the upper part of the structure.

[0024] Figure 3 This is a utility model Figure 1 The diagram shows an enlarged view of the middle section.

[0025] Figure 4 This is a utility model Figure 1 The diagram shows an enlarged view of the lower part of the structure.

[0026] The markings in the diagram are as follows: 1 is the coupling, 2 is the protective cap, 3 is the first guide shoe, 4 is the unsealing sleeve, 5 is the shearing cap, 6 is the retrieval head, 7 is the protective cone, 8 is the sandproof rubber sleeve, 9 is the slip cover, 10 is the upper cone, 11 is the slip, 12 is the slip spring, 13 is the first nut, 14 is the lower cone, 15 is the upper pressure ring, 16 is the rubber sleeve shaft, 17 is the central tube, 18 is the insertion tube, 19 is the lower pressure ring, 20 is the second nut, 21 is the second locking spring, 22 is the first connecting sleeve, 23 is the small rubber sleeve, 24 is the first positioning cap, and 25 is the retaining ring. 26 is the second positioning cap, 27 is the main piston, 28 is the second guide shoe, 29 is the first locking block, 30 is the auxiliary piston, 31 is the second locking block, 32 is the cylinder liner, 33 is the third nut, 34 is the lower short connector, 35 is the ball seat, 36 is the second connecting sleeve, 37 is the blowout preventer, 38 is the elastic sleeve, 39 is the sealing sleeve, 40 is the sealing rubber sleeve, 41 is the lower connector, 42 is the first shear pin, 43 is the second shear pin, 44 is the rubber sleeve, 45 is the O-ring, 46 is the third shear pin, 47 is the steel ball, and 48 is the fourth shear pin. Detailed Implementation

[0027] Combined with appendix Figure 1 As shown, this embodiment provides a retrieval and drillable pipe-type isolation mining device, which mainly consists of three major assemblies, including a pipe assembly, an anchoring and sealing assembly, and a blowout preventer assembly connected in sequence from top to bottom.

[0028] Combined with appendix Figure 1 and attached Figure 2 As shown, the insertion tube assembly is a movable component that connects to and moves up and down with the production tube column, including a coupling 1, a protective cap 2, an insertion tube 18, a second nut 20, a second guide shoe 28, a second connecting sleeve 36, and an elastic sleeve 38.

[0029] The outer side of the coupling 1 is threaded to the cap 2, and the inner side is threaded to the upper end of the insertion tube 18. The lower end of the insertion tube 18 is threaded to the second nut 20. On the outer side of the second nut 20, a small rubber sleeve 23, a first positioning cap 24, a retaining ring 25, and a second positioning cap 26 are sequentially fitted, forming a dynamic sealing assembly. The lower end of the second nut 20 is threaded to the second guide shoe 28, which also has a small rubber sleeve 23. The lower end of the second guide shoe 28 is threaded to the second connecting sleeve 36; inside the second connecting sleeve 36, a ball seat 35 is fixed by a fourth shear pin 48, and the ball seat 35 can support a steel ball 47. The lower end of the second connecting sleeve 36 is threaded to the elastic sleeve 38, and the elastic claw spring at the lower end of the elastic sleeve 38 is the driving component controlling the opening and closing of the blowout preventer valve.

[0030] Combined with appendix Figure 1 , 2 As shown in Figure 3, the anchoring seal assembly is a fixed component set downhole, including a central tube 17, and a setting mechanism, an anchoring mechanism, a sealing mechanism, and an unsealing mechanism sleeved outside the central tube 17.

[0031] The central tube 17 passes through the anchoring and sealing assembly, and the second guide shoe 28 and the central tube 17 are initially positioned by the second locking block 31.

[0032] The unsealing mechanism includes a first guide shoe 3, an unsealing sleeve 4, a retrieval head 6, and a protective cone 7. The first guide shoe 3 is threadedly connected to the unsealing sleeve 4. Inside the first guide shoe 3, a shearing cap 5 is fixed by a first shearing pin 42, and the shearing cap 5 is threadedly connected to the upper part of the insertion tube 18. The unsealing sleeve 4 is threadedly connected to the upper end of the central tube 17, and inside it, the retrieval head 6 is fixed by a second shearing pin 43. The lower end of the unsealing sleeve 4 is threadedly connected to the protective cone 7 and the upper cone 10, respectively. The outer sides of the protective cone 7 and the upper cone 10 are jointly provided with a sand-proof rubber sleeve 8.

[0033] The anchoring mechanism includes a slip cover 9, a slip 11, an upper cone 10, and a lower cone 14. The slip cover 9 is positioned on the outer side of the upper cone 10 via a shoulder. The slip 11 is located inside the slip cover 9, and a slip spring 12 is provided between the slip 11 and the slip cover 9. The lower end of the slip cover 9 is threadedly connected to a first nut 13, and the lower cone 14 is located inside it, with the lower cone 14 positioned to the first nut 13 via a shoulder.

[0034] The protective cone 7, upper cone 10, slip 11, and slip cover 9 are made of drillable material, which can accurately and efficiently drill and grind to release the anchor when stuck. This is a backup plan to achieve the "drillable" function and ensure operational safety.

[0035] The sealing mechanism includes a rubber sleeve shaft 16, a rubber sleeve 44, an upper pressure ring 15, and a lower pressure ring 19. The inner side of the lower cone 14 is threaded to the rubber sleeve shaft 16, and the outer side is threaded to the upper pressure ring 15. The rubber sleeve 44 and the lower pressure ring 19 are located on the outer side of the rubber sleeve shaft 16. An O-ring 45 is provided on the sealing surface of the rubber sleeve 44 to enhance the seal. The lower pressure ring 19 is threaded to the first connecting sleeve 22.

[0036] The setting mechanism includes a main piston 27, a secondary piston 30, a first connecting sleeve 22, and a cylinder liner 32. The main piston 27 has a first locking block 29 inside, which positions it against the central tube 17. The main piston 27 is threadedly connected to the first connecting sleeve 22. A cylinder liner 32 is located on the outer side of the first connecting sleeve 22. A second locking spring 21 on the inner side of the cylinder liner 32 forms a one-way lock with the first connecting sleeve 22, ensuring that it does not retract after setting. The lower end of the cylinder liner 32 is threadedly connected to a third nut 33, and the inner side of the third nut 33 is threadedly connected to a lower short connector 34. The lower short connector 34 is threadedly connected to the lower part of the central tube 17. A secondary piston 30 is located on the lower short connector 34, and the secondary piston 30 is fixed to the main piston 27 by a third shear pin 46.

[0037] Combined with appendix Figure 1 and attached Figure 4 As shown, the blowout preventer assembly is connected at the lowest end and includes a lower short connector 34, a blowout preventer sleeve 37, and a sealing sleeve 39. The lower short connector 34 internally houses the blowout preventer sleeve 37, which is positioned with the second connecting sleeve 36 via a shoulder. The lower short connector 34 is threadedly connected to the sealing sleeve 39, which contains a sealing rubber sleeve 40. The lower end of the sealing sleeve 39 is threadedly connected to the lower connector 41. The insertion tube 18 can be inserted into the anchoring seal assembly and the blowout preventer assembly, forming a sealing fit with the sealing rubber sleeve 40.

[0038] The working principle of this device is as follows:

[0039] Setting: Connect the device to the tubing string and lower it to the designed well depth. Insert steel ball 47 into ball seat 35 from the tubing. Pressurize the tubing; the pressure pushes the auxiliary piston 30 downwards, shearing the third shear pin 46 and releasing the lock on the main piston 27. Under pressure, the main piston 27 moves upwards, pushing the first connecting sleeve 22, lower pressure ring 19, and other components, compressing the rubber sleeve 44 to create an annular space in its sealing sleeve 39, and pushing the lower cone 14 upwards to expand the lower part of the slip 11, achieving lower anchoring. Simultaneously, the auxiliary piston 30 moves downwards, driving the central tube 17, unsealing sleeve 4, and upper cone 10 downwards, shearing the first shear pin 42, causing the upper cone 10 to expand the upper part of the slip 11, achieving upper anchoring. The pressure continues to rise to the set value, the fourth shear pin 48 is sheared, and the ball seat 35 and steel ball 47 fall into the lower tubing.

[0040] Bottom Valve Opening and Production: After setting, the production tubing (with pump) is lowered. The insertion tube 18 at the bottom of the production tubing is lowered along with the tubing and inserted into the blowout preventer bottom valve assembly. The lower end of the insertion tube 18 pushes open the elastic sleeve 38, forcing the blowout preventer sleeve 37 downward until the elastic claw spring on it engages with the groove of the lower shorting connector 34. At this time, the fluid sampling channel is opened, and oil can flow into the production tubing through the channel between the blowout preventer sleeve 37 and the lower shorting connector 34.

[0041] Bottom valve closure and pump inspection: When pump inspection is required, the production tubing is lifted. The insertion tube 18 moves upward, causing the elastic sleeve 38 to move upward. The elastic sleeve 38 hooks onto the mounting platform of the blowout preventer 37, causing it to move upward together, disengaging from the groove of the lower short connector 34, until the upper end face of the blowout preventer 37 is limited by the lower end face of the central tube 17. The elastic sleeve 38 disengages from the blowout preventer 37, and the blowout preventer 37 falls back under its own weight or spring force (if provided), sealing the fluid collection channel and achieving upper and lower layer isolation.

[0042] Unsealing and salvage:

[0043] Retrieval method: Lower a special retractable retrieval tool and connect it with the retrieval head 6. Lift the retrieval tool to cut the second shear pin 43, which will drive the unsealing sleeve 4, upper cone 10, lower cone 14 and other components to move upward, causing the slip 11 to lose cone support and retract under the action of the slip spring 12. The rubber sleeve 44 will elastically reset, thus achieving unsealing. Then, the device can be lifted out.

[0044] Drillable method: If the retrieval method fails due to jamming, the retrieval tool can be withdrawn, and a milling retrieval tool with a screw drill bit can be lowered. The screw drill bit drives the milling shoe to remove the jamming components such as the slip cover 9, upper cone 10, and lower cone 14 made of easily drillable material. After the anchoring is released, the remaining part of the device can be retrieved.

[0045] It is understood that the above specific description of this utility model is only used to illustrate this utility model and is not limited to the technical solutions described in the embodiments of this utility model. Those skilled in the art should understand that modifications or equivalent substitutions can still be made to this utility model to achieve the same technical effect; as long as the use needs are met, they are all within the protection scope of this utility model.

Claims

1. A fishable, drillable, cannulated, interposition device, comprising: The device includes, from top to bottom, a cannula assembly, an anchoring and sealing assembly, and a blowout preventer assembly. The cannula assembly includes a coupling (1), a cap (2), and a cannula (18). The outer side of the coupling (1) is threaded to the cap (2), and the inner side is threaded to the upper end of the cannula (18). The anchoring and sealing assembly includes a central tube (17), and a setting mechanism, an anchoring mechanism, a sealing mechanism, and an unsealing mechanism fitted outside the central tube (17). The blowout preventer assembly includes a lower short connector (34), a blowout preventer sleeve (37), and a sealing sleeve (39). The lower short connector (34) is threaded to the sealing sleeve (39), and a sealing rubber sleeve (40) is provided inside the sealing sleeve (39). The cannula (18) can be inserted into the anchoring and sealing assembly and the blowout preventer assembly, and form a sealing fit with the sealing rubber sleeve (40).

2. A fishable and drillable, cased, separate-and-abandon device according to claim 1, characterized in that The cannula assembly further includes a second nut (20), a second guide shoe (28), a second connecting sleeve (36), and an elastic sleeve (38); the lower end of the cannula (18) is threadedly connected to the second nut (20); the lower end of the second nut (20) is threadedly connected to the second guide shoe (28); the lower end of the second guide shoe (28) is threadedly connected to the second connecting sleeve (36); the lower end of the second connecting sleeve (36) is threadedly connected to the elastic sleeve (38); a small rubber tube (23), a first positioning cap (24), a retaining ring (25), and a second positioning cap (26) are provided on the outside of the second nut (20); the small rubber tube (23) is provided on the second guide shoe (28); a ball seat (35) is provided inside the second connecting sleeve (36), and the ball seat (35) is fixed to the second connecting sleeve (36) by a fourth shear pin (48); a steel ball (47) is provided inside the ball seat (35).

3. A fishable and drillable, cased, separate-and-abandon device according to claim 1, wherein, The anchoring mechanism includes a slip cover (9), a slip (11), an upper cone (10), and a lower cone (14); the slip cover (9) is provided on the outside of the upper cone (10) and is positioned by a shoulder; the slip (11) is provided inside the slip cover (9), and a slip spring (12) is provided between the slip (11) and the slip cover (9); the lower end of the slip cover (9) is threadedly connected to a first nut (13); the lower cone (14) is provided inside the lower end of the slip cover (9), and the lower cone (14) is positioned by a shoulder of the first nut (13).

4. The retrievable and drillable insert-type isolation mining device according to claim 3, characterized in that, The sealing mechanism includes a rubber sleeve shaft (16), a rubber sleeve (44), an upper pressure ring (15), and a lower pressure ring (19); the inner side of the lower cone (14) is threaded to the rubber sleeve shaft (16), and the outer side is threaded to the upper pressure ring (15); the rubber sleeve (44) and the lower pressure ring (19) are provided on the outer side of the rubber sleeve shaft (16); an O-ring (45) is provided on the sealing surface of the rubber sleeve (44).

5. A fishable and drillable packer assembly according to claim 3, wherein, The unsealing mechanism includes a first guide shoe (3), an unsealing sleeve (4), a retrieval head (6), and a protective cone (7); the first guide shoe (3) is threadedly connected to the unsealing sleeve (4); the first guide shoe (3) is provided with a shear cap (5) and fixed by a first shearing nail (42); the unsealing sleeve (4) is threadedly connected to the central tube (17); the unsealing sleeve (4) is provided with the retrieval head (6) and fixed by a second shearing nail (43); the lower end of the unsealing sleeve (4) is threadedly connected to the protective cone (7) and the upper cone (10) respectively; the protective cone (7) and the upper cone (10) are provided with sandproof rubber sleeves (8) on their outer sides.

6. A fishable and drillable, cased, straddle device according to claim 1, wherein, The setting mechanism includes a main piston (27), a secondary piston (30), a first connecting sleeve (22), and a cylinder liner (32); the main piston (27) is threadedly connected to the first connecting sleeve (22); a first locking block (29) is provided inside the main piston (27), and the main piston (27) and the central tube (17) are positioned by the first locking block (29); the cylinder liner (32) is provided on the outside of the first connecting sleeve (22); a second locking spring (21) is provided on the inside of the cylinder liner (32), and the second locking spring (21) forms a one-way lock with the first connecting sleeve (22); the lower end of the cylinder liner (32) is threadedly connected to a third nut (33); the inside of the third nut (33) is threadedly connected to a lower short connector (34); the lower short connector (34) is threadedly connected to the central tube (17); the secondary piston (30) is provided on the lower short connector (34); the secondary piston (30) and the main piston (27) are fixed by a third shear pin (46).

7. A fishable and drillable packer assembly according to claim 2, wherein, In the blowout preventer assembly, the lower short connector (34) is provided with the blowout preventer sleeve (37), and the blowout preventer sleeve (37) is positioned with the shoulder of the second connecting sleeve (36); the lower end of the sealing sleeve (39) is threadedly connected to the lower connector (41).

8. A fishable and drillable packer assembly according to claim 5, wherein, The protective cone (7), the upper cone (10), the slip (11), and the slip cover (9) are made of a drillable material.

Images