Scraping and setting integrated bridge plug for well completion operation

Abstract

The utility model relates to the technical field of oil and gas field well completion operation tools, and aims to solve the problems that the existing bridge plug needs to be fed and set by a special setting tool, so that the well descending difficulty and the drilling tool jamming risk are high; the scraping and setting integrated bridge plug for well completion operation aims at solving the problems that in the prior art, an existing bridge plug is not provided with a pipe scraping operation function, and increasingly complex and diversified operation requirements of an oil field are difficult to meet. The scraping and setting integrated bridge plug comprises a setting mechanism, an anchoring mechanism and a sealing assembly; the anchoring mechanism comprises a central pipe, an upper end slip, a lower end slip, an upper cone, a lower cone, a first guiding shoe and a locking ring; the pipe scraping device further comprises a pipe scraping mechanism, the pipe scraping mechanism comprises a pipe scraper body and a spiral pipe scraping piece, the pipe scraper body is arranged at the lower end of the central pipe in a sleeving mode and attached to the end face of the lower end slip, and the spiral pipe scraping piece is installed on the periphery of the pipe scraper body through a compression spring. The scraping and setting integrated bridge plug does not need to be equipped with a special setting tool; and a pipe scraping function is integrated, so that the inner wall of an oil pipe can be effectively scraped and cleaned while the bridge plug realizes a packing function.

Description

Technical Field

[0001] This utility model relates to the technical field of well completion tools for oil and gas fields, and more specifically, to a scraper-seat integrated bridge plug for well completion operations. Background Technology

[0002] Currently, bridge plugs used domestically are mainly divided into mechanical bridge plugs, hydraulic bridge plugs, or cable bridge plugs. The use of these bridge plugs requires specialized setting tools for insertion and setting. However, the total length of typical setting tools is around 2 meters, increasing the difficulty of running the bridge plug into the well and the risk of stuck pipe. On the other hand, during oilfield production, impurities such as wax and scale may adhere to the inner wall of the tubing, affecting normal well production and subsequent operations. Scraping operations are crucial for cleaning the inner wall of the tubing and ensuring its unobstructed flow. However, most existing bridge plugs focus on the sealing function, with few possessing scraping capabilities. Scrapers are also sent down into the well to clean the casing wall using specialized tools. Existing casing wire brush workover tools have complex structures, low efficiency when brushing casing, inconvenient maintenance, and are prone to losing wire in the well. Currently, there is a shortage of bridge plug products that simultaneously meet the requirements of simple structure, no need for special setting tools, combination of hydraulic and mechanical bridge plug advantages, meet the requirements of oilfields for bridge plug setting, and have pipe scraping operation function, making it difficult to fully adapt to the increasingly complex and diversified operational needs of oilfields.

[0003] Therefore, there is an urgent need for a bridge plug that is simple in structure, easy to use, requires no special setting tools, meets the requirements of oilfields for bridge plug setting, and has the function of scraping pipe operation for well completion operations. Utility Model Content

[0004] The purpose of this invention is to solve the problems of existing bridge plugs, which require specialized setting tools for insertion and setting, resulting in high difficulty in running them into the well and a high risk of stuck pipe; and they lack the function of scraping casing, making them difficult to adapt to the increasingly complex and diverse operational needs of oilfields. This invention provides a bridge plug with integrated scraping and setting for well completion operations, which achieves a simple structure, is easy to use, requires no specialized setting tools, and integrates the function of a high-efficiency scraper for cleaning casing, thus meeting the technical requirements of oilfields for bridge plug setting and scraper workover.

[0005] This utility model is achieved through the following technical solution: a scraper-seat integrated bridge plug for well completion operations, comprising a setting mechanism, an anchoring mechanism, and a sealing assembly; the anchoring mechanism includes a central tube, an upper slip, a lower slip, an upper cone, a lower cone, a first guide shoe, and a locking ring; the upper slip is fitted onto the upper end of the central tube, the upper cone is fitted onto the central tube and fits against the conical surface of the upper slip, and a first shear pin passes between the upper cone and the central tube; the locking ring is screwed into the upper cone, and the end of the locking ring is provided with a first shear pin. A retaining ring; the lower end slip is fitted onto the lower end of the central tube and fixedly connected to the first guide shoe, the first guide shoe being fitted onto the lower end thread of the central tube; the lower cone is fitted onto the central tube and fits against the conical surface of the lower end slip; the integrated scraper bridge plug also includes a scraper mechanism, the scraper mechanism including a scraper body and a spiral scraper blade, the scraper body being fitted onto the lower end of the central tube and fits against the end face of the lower end slip, and multiple spiral scraper blades being respectively installed on the outer periphery of the scraper body by compression springs.

[0006] Preferably, the scraper body has multiple radial grooves, which are divided into multiple groups. The multiple groups of radial grooves are distributed at intervals along the length of the scraper body, and each group of radial grooves is arranged at intervals along the circumference of the scraper body. Multiple through holes are formed between each group of radial grooves of the scraper body. Multiple spiral scraper blades are respectively installed in the multiple radial grooves. One end of the compression spring is detachably connected to the scraper body, and the other end of the compression spring is detachably connected to the spiral scraper blade.

[0007] Preferably, a second retaining ring is fitted onto one end of the scraper body near the central tube.

[0008] Preferably, a second guide shoe is fitted onto the end of the scraper body away from the central tube.

[0009] Preferably, the setting mechanism includes an inlet connector, an upper connector, a piston, a hook connector, a release plug, and a plug. The inlet connector is threaded to the upper end of the upper connector. The piston is sleeved on the upper connector. The upper connector has a liquid inlet hole at the connection between its inclined surface and the piston. A second shear pin passes between the piston and the upper connector. The lower end of the upper connector is threaded to the hook connector. The outer wall of the hook connector has a boss. The upper end of the release plug is threaded to the hook connector. The lower end of the release plug is threaded to the plug. The release plug has a locking spring. The plug is threaded onto the internal thread of the central tube.

[0010] Preferably, the thread at the connection between the feed connector and the upper connector is a left-hand thread structure.

[0011] Preferably, the sealing assembly includes a rubber sleeve, which is sleeved on the central tube and located between the upper cone and the lower cone, and a retaining ring is provided inside the rubber sleeve.

[0012] Preferably, the sealing assembly further includes two sets of inner back rings and outer back rings, the inner back rings and the outer back rings being fitted together through grooves, the two sets of inner back rings and outer back rings being respectively disposed on the upper cone and the lower cone, and the inner back rings being positioned facing the rubber sleeve, and the outer back rings being positioned facing the upper cone or the lower cone.

[0013] Preferably, the sealing assembly further includes a plurality of O-rings, which are respectively disposed at the root of the upper connector and the feed connector sleeve, at the piston sleeve with the upper connector, at the ends of the upper slip and the lower slip, at the retaining ring sleeve with the central tube, and at the plug sleeve with the central tube.

[0014] The technical solution of this utility model has the following beneficial effects:

[0015] (1) The setting and scraping functions are integrated into a single design: On the one hand, there is no need to equip the setting tools with special, complex and long tools, which reduces the operating cost and difficulty, improves the operating efficiency and adapts to the operating environment with limited total length. The short total length of the tool reduces the difficulty of running the bridge plug into the well and the risk of stuck drill bit. On the other hand, the scraping mechanism is cleverly integrated into the bridge plug structure, so that the bridge plug can effectively scrape and clean the inner wall of the tubing while realizing the sealing function, ensuring the cleanliness and smooth flow of the inner wall of the tubing. After the bridge plug is set, the original tubing string can be used directly to empty the ash without running another tubing string, which improves the overall operating effect and production efficiency of the oilfield.

[0016] (2) During the scraping process, the spiral scraper blades extend and retract under the restoring force of the compression spring, allowing them to make close contact with the inner wall of the casing. When the integrated bridge plug moves along the axial direction of the casing, the spiral scraper blades can scrape away debris from the inner wall of the casing, thus achieving the function of milling the casing. Multiple through holes facilitate the circulation of external water to flush the wellbore.

[0017] (3) The feed connector is designed with a left-hand thread to ensure that it can be turned right-handed to release the device in an emergency. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the integrated scraper and seat bridge plug in Embodiment 1 of this utility model;

[0019] Figure 2 This is a cross-sectional view of the integrated bridge plug with scraper and seat in Embodiment 1 of this utility model;

[0020] Figure 3 for Figure 2 A magnified structural diagram of part A in the middle;

[0021] Figure 4 This is a schematic diagram of the scraping mechanism in Embodiment 1 of this utility model;

[0022] Figure 5 This is a side view schematic diagram of the scraping mechanism in Embodiment 1 of this utility model.

[0023] Reference numerals: 1-Setting mechanism, 11-Infeed connector, 12-Upper connector, 12a-Liquid inlet, 13-Piston, 14-Hanging connector, 15-Release plug, 16-Plug, 17-Second shear pin, 18-Boss, 19-Locking spring, 2-Anchoring mechanism, 21-Central tube, 22-Upper end slip, 23-Lower end slip, 24-Upper cone, 25-Lower cone, 26-First guide shoe, 27-Locking ring, 28-First shear pin, 29-First retaining ring, 3-Sealing assembly, 31-Rubber sleeve, 32-Retention ring, 33-Inner back ring, 34-Outer back ring, 35-O-ring seal, 4-Scraper mechanism, 41-Scraper body, 41a-Radial groove, 41b-Through hole, 42-Spiral scraper blade, 43-Compression spring, 44-Second retaining ring, 45-Second guide shoe, 5-Steel ball. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown herein can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] Example 1

[0028] like Figures 1 to 5As shown, this embodiment provides a scraper-seat integrated bridge plug for well completion operations, including a setting mechanism 1, an anchoring mechanism 2, and a sealing assembly 3. The anchoring mechanism 2 includes a central tube 21, an upper slip 22, a lower slip 23, an upper cone 24, a lower cone 25, a first guide shoe 26, and a locking ring 27. The upper slip 22 is fitted onto the upper end of the central tube 21, and the upper cone 24 is fitted onto the central tube 21 and fits against the conical surface of the upper slip 22. A first shear pin 28 passes between the upper cone 24 and the central tube 21. The locking ring 27 is screwed into the upper cone 24, and a first retaining ring 29 is provided at the end of the locking ring 27. The end slip 23 is fitted onto the lower end of the central tube 21 and fixedly connected to the first guide shoe 26, which is fitted onto the threaded lower end of the central tube 21. The lower cone 25 is fitted onto the central tube 21 and fits against the conical surface of the lower end slip 23. The integrated bridge plug also includes a scraping mechanism 4, which includes a scraper body 41 and spiral scraper blades 42. The scraper body 41 is fitted onto the lower end of the central tube 21 and fits against the end face of the lower end slip 23. The scraper body 41 is threadedly connected to the central tube 21. Multiple spiral scraper blades 42 are respectively installed on the outer periphery of the scraper body 41 by compression springs 43.

[0029] This integrated bridge plug combines setting and tubing scraping functions in a single, integrated design to meet various performance requirements. Firstly, it eliminates the need for specialized, complex, and lengthy setting tools, reducing operating costs and difficulty, improving efficiency, and adapting to environments with limited overall length. The shorter tool length also reduces the difficulty of running the bridge plug into the well and the risk of stuck pipe. Secondly, the cleverly integrated tubing scraping mechanism 4 allows the bridge plug to effectively scrape and clean the tubing wall while simultaneously performing its sealing function, ensuring cleanliness and unobstructed flow. Furthermore, because this bridge plug is designed as an integrated setter and scraper, after setting, the original tubing string can be used directly for ash removal, unlike bridge plugs without a scraping function which require first running a scraping string, then removing the scraping string, and finally running the bridge plug string for ash removal. This improves the overall operational efficiency and production effectiveness of the oilfield.

[0030] In this embodiment, the scraper body 41 has multiple radial grooves 41a, which are divided into multiple groups. The multiple groups of radial grooves 41a are distributed at intervals along the length of the scraper body 41. Each group of radial grooves 41a is arranged at intervals along the circumference of the scraper body 41. Multiple through holes 41b are provided between each group of radial grooves 41a of the scraper body 41. Multiple spiral scraper blades 42 are respectively installed in the multiple radial grooves 41a. One end of the compression spring 43 is welded to the scraper body 41, and the other end of the compression spring 43 is welded to the spiral scraper blades 42.

[0031] During casing scraping, the spiral scraper blade 42 extends and retracts under the restoring force of the compression spring 43, allowing it to make close contact with the inner wall of the casing. When the integrated bridge plug moves along the casing axial direction, the spiral scraper blade 42 can scrape away debris from the inner wall of the casing, achieving the function of casing milling. Multiple through holes 41b facilitate external water source circulation for flushing the wellbore.

[0032] In this embodiment, a second retaining ring 44 is also fitted onto one end of the scraper body 41 near the central tube 21. The connection between the second retaining ring 44 and the scraper body 41 can provide radial compression and limiting for the spiral scraper blade 42. Furthermore, the second retaining ring 44 and the scraper body 41 are fixed by hexagonal head screws.

[0033] In this embodiment, a second guide shoe 45 is fitted onto the end of the scraper body 41 furthest from the central tube 21. The second guide shoe 45 serves to limit the movement of the spiral scraper blade 42, ensuring that it is fixed and locked in the correct position. Furthermore, both the first guide shoe 26 and the second guide shoe 45 are fixed by hexagonal set screws.

[0034] In this embodiment, the setting mechanism 1 includes an inlet connector 11, an upper connector 12, a piston 13, a hook connector 14, a release plug 15, and a plug 16. The inlet connector 11 is threadedly connected to the upper end of the upper connector 12. The piston 13 is sleeved on the upper connector 12. The upper connector 12 has a liquid inlet hole 12a at the connection between its inclined surface and the piston 13. A second shear pin 17 passes between the piston 13 and the upper connector 12. The lower end of the upper connector 12 is threadedly connected to the hook connector 14. The outer wall of the hook connector 14 has a boss 18. The upper end of the release plug 15 is threadedly connected to the hook connector 14, and the lower end of the release plug 15 is threadedly connected to the plug 16. A locking spring 19 is provided on the release plug 15. The plug 16 is threaded onto the internal thread of the central tube 21. Furthermore, both the first shear pin 28 and the second shear pin 17 are fixed by set screws to prevent them from coming loose.

[0035] In this embodiment, the thread at the connection between the feed connector 11 and the upper connector 12 is a left-hand thread. The left-hand thread structure ensures that the device can be turned right-hand to release the device in an emergency.

[0036] In this embodiment, the sealing assembly 3 includes a rubber sleeve 31, which is fitted onto the central tube 21 and located between the upper cone 24 and the lower cone 25. A retaining ring 32 is disposed inside the rubber sleeve 31. The rubber sleeve 31 forms a seal in the structure, preventing fluid leakage through the connection between the upper cone 24 and the lower cone 25; the retaining ring 32 provides load-bearing and support, ensuring the stability and safety of the structure.

[0037] In this embodiment, the sealing assembly 3 further includes two sets of inner back rings 33 and outer back rings 34. The inner back rings 33 and outer back rings 34 are fitted together through grooves. The two sets of inner back rings 33 and outer back rings 34 are respectively disposed on the upper cone 24 and the lower cone 25, with the inner back ring 33 facing the rubber sleeve 31 and the outer back ring 34 facing the upper cone 24 or the lower cone 25. The inner back rings 33 and outer back rings 34 can further improve the sealing effect.

[0038] In this embodiment, the sealing assembly 3 further includes multiple O-rings 35, which are respectively disposed at the root of the upper connector 12 and the insertion connector 11, at the connection between the piston 13 and the upper connector 12, at the ends of the upper slip 22 and the lower slip 23, at the connection between the retaining ring 32 and the central tube 21, and at the connection between the plug 16 and the central tube 21. Each of the above-mentioned sealing rings is disposed in a corresponding sealing groove.

[0039] Specific workflow:

[0040] S1: When the integrated bridge plug is run into the well, its upper end is connected to the tubing or drill pipe. It is lowered to the setting depth. By repeatedly lifting or lowering the integrated bridge plug, the spiral scraper blades 42 of the scraper mechanism 4 scrape the tubing near the designed setting point several times. External equipment, such as the pump of the pump truck, is opened to circulate and flush the wellbore, which plays the role of scraping the tubing.

[0041] S2: A steel ball 5 is dropped into the wellhead. The steel ball 5 falls freely into place and sits on the coupling 14. The oil pipe or drill pipe is used to pressurize the fluid. The high-pressure fluid reaches the inlet hole 12a of the upper coupling 12 from the feed joint 11. Using the ball, the hydraulic pressure generated by the oil pipe acts on the piston 13. When the hydraulic pressure reaches the set pressure, the piston 13 shears the second shear pin 17 and moves downward to squeeze the upper slip 22. The pump continues to pressurize. The upper slip 22 moves downward along the upper cone 24 and breaks and is embedded in the inner wall of the casing. When the pressure suddenly drops to 0, it means that the upper slip 22 has been set and the piston 13 loses its seal.

[0042] S3: At this time, the pressure is released, the tubing or drill pipe is pulled out downhole, and the pulling force drives the first guide shoe 26 to move upward and compress the lower slip 23. Through the upper cone 24 and the lower cone 25, two forces, pressure and pull, are applied to the sealing rubber sleeve 31. Within a certain range of tension, the lower slip 23 of the bridge plug ruptures, the rubber sleeve 31 expands and seals, and the setting seal is completed.

[0043] S4: When the pulling force continues to rise to a certain value, the release plug 15 is broken, and the components above the upper slip are disengaged from the bridge plug. At the same time, the piston 13 is carried out of the wellbore by the boss 18 on the coupling 14, completing the release. During the setting and release process, the scraper mechanism moves up and down with the bridge plug.

[0044] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A scraper-and-seat integrated bridge plug for well completion operations, characterized in that, It includes a setting mechanism (1), an anchoring mechanism (2), and a sealing assembly (3); The anchoring mechanism (2) includes a central tube (21), an upper slip (22), a lower slip (23), an upper cone (24), a lower cone (25), a first guide shoe (26), and a locking ring (27). The upper slip (22) is fitted onto the upper end of the central tube (21), and the upper cone (24) is fitted onto the central tube (21) and fits against the conical surface of the upper slip (22). A first shear is inserted between the upper cone (24) and the central tube (21). Cutting pin (28); the locking ring (27) is screwed into the upper cone (24), and the end of the locking ring (27) is provided with a first retaining ring (29); the lower end slip (23) is sleeved on the lower end of the central tube (21) and fixedly connected to the first guide shoe (26), and the first guide shoe (26) is sleeved on the lower end thread of the central tube (21); the lower cone (25) is sleeved on the central tube (21) and fits against the conical surface of the lower end slip (23); The integrated bridge plug also includes a scraping mechanism (4), which includes a scraper body (41) and spiral scraper blades (42). The scraper body (41) is sleeved on the lower end of the central tube (21) and fits against the end face of the lower end slip (23). Multiple spiral scraper blades (42) are respectively installed on the outer periphery of the scraper body (41) by compression springs (43).

2. The integrated scraper-and-seat bridge plug for well completion operations according to claim 1, characterized in that, The scraper body (41) has a plurality of radial grooves (41a), which are divided into multiple groups. The multiple groups of radial grooves (41a) are distributed at intervals along the length of the scraper body (41). Each group of radial grooves (41a) is arranged at intervals along the circumference of the scraper body (41). A plurality of through holes (41b) are provided between each group of radial grooves (41a) of the scraper body (41). Multiple spiral scraper blades (42) are respectively installed in multiple radial grooves (41a). One end of the compression spring (43) is detachably connected to the scraper body (41), and the other end of the compression spring (43) is detachably connected to the spiral scraper blades (42).

3. The integrated scraper-and-seat bridge plug for well completion operations according to claim 1, characterized in that, The scraper body (41) is also fitted with a second retaining ring (44) at one end near the central tube (21).

4. The integrated scraper-and-seat bridge plug for well completion operations according to claim 1, characterized in that, A second guide shoe (45) is fitted onto one end of the scraper body (41) away from the central tube (21).

5. The integrated scraper-and-seat bridge plug for well completion operations according to any one of claims 1 to 4, characterized in that, The sealing mechanism (1) includes an inlet connector (11), an upper connector (12), a piston (13), a hook connector (14), a release plug (15), and a plug (16). The inlet connector (11) is threadedly connected to the upper end of the upper connector (12). The piston (13) is sleeved on the upper connector (12). The upper connector (12) has an inlet hole (12a) at the connection point with the inclined surface of the piston (13). The piston (13) and the upper connector (12) pass through a through-hole. A second shear pin (17) is provided; the lower end of the upper connector (12) is threadedly connected to the hook connector (14), and the outer wall of the hook connector (14) is provided with a boss (18); the upper end of the release plug (15) is threadedly connected to the hook connector (14), and the lower end of the release plug (15) is threadedly connected to the plug (16), and the release plug (15) is provided with a locking spring (19); the plug (16) is provided on the internal thread of the central tube (21) through a threaded structure.

6. The integrated scraper-and-seat bridge plug for well completion operations according to claim 5, characterized in that, The thread at the connection between the feed connector (11) and the upper connector (12) is a left-hand thread structure.

7. The integrated scraper-and-seat bridge plug for well completion operations according to claim 5, characterized in that, The sealing assembly (3) includes a rubber sleeve (31), which is sleeved on the central tube (21) and located between the upper cone (24) and the lower cone (25). A retaining ring (32) is provided inside the rubber sleeve (31).

8. The integrated scraper-and-seat bridge plug for well completion operations according to claim 7, characterized in that, The sealing assembly (3) further includes two sets of inner back rings (33) and outer back rings (34). The inner back rings (33) and the outer back rings (34) are fitted together through grooves. The two sets of inner back rings (33) and the outer back rings (34) are respectively disposed on the upper cone (24) and the lower cone (25), and the inner back rings (33) are kept facing the rubber sleeve (31), and the outer back rings (34) are facing the upper cone (24) or the lower cone (25).

9. The integrated scraper-and-seat bridge plug for well completion operations according to claim 7, characterized in that, The sealing assembly (3) also includes a plurality of O-rings (35), which are respectively disposed at the root of the upper connector (12) and the feed connector (11), at the connection between the piston (13) and the upper connector (12), at the ends of the upper slip (22) and the lower slip (23), at the connection between the retaining ring (32) and the central tube (21), and at the connection between the plug (16) and the central tube (21).

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