Underwater oil and gas production tree tubing hanger blanking plug

Abstract

The utility model discloses an underwater oil and gas production tree tubing hanger plug which comprises a plug body, a metal sealing ring and a guide plate which are axially connected in sequence, and an inner fishing assembly is movably connected in the front end of the plug body. A first annular step is arranged at the position, close to the metal sealing ring, of the rear end of the plug body, the first annular step is sequentially sleeved with a first supporting ring, a first V-shaped sealing ring, an O-shaped ring, a second V-shaped sealing ring and a second supporting ring in the axial direction, and the end face, away from the second V-shaped sealing ring, of the second supporting ring makes contact with the front end of the metal sealing ring. According to the underwater oil production and gas production tree tubing hanger blanking plug, the metal sealing ring is matched with the first supporting ring, the first V-shaped sealing ring, the O-shaped ring, the second V-shaped sealing ring and the second supporting ring, multiple sealing is achieved, the blanking plug can move up and down in the working barrel while sealing is achieved, and the blanking plug is convenient to use. Therefore, the blanking plug is easy and convenient to salvage and easy to operate.

Description

Technical Field

[0001] This utility model relates to the field of sealing technology for underwater oil and gas production equipment, specifically to a plugging device for underwater oil and gas production tree pipes. Background Technology

[0002] Subsea production tree tubing plugs are sealing tools that sit inside the subsea production tree. When the production tree is in production mode, the plug prevents the oil medium from leaking upwards from the tubing. Sealing is a crucial aspect of the plug; traditional elastomeric sealing technology is mature and low-cost, and was widely used in the early stages of development. However, existing subsea production tree tubing plugs can experience problems such as loss of control, failure, or unstable sealing pressure. Failure of these plugs increases safety risks in oil / gas well production, leads to the shutdown of some wells, and may even cause the entire well to become unusable, thus putting pressure on maintaining stable production and efficiency. Furthermore, once a subsea production tree tubing plug leaks, the well faces difficulties such as high workover costs, difficulty in well repair, and even the inability to repair the well. Once an oil / gas well stops production, restarting it becomes extremely difficult. Utility Model Content

[0003] The purpose of this invention is to provide a plugging device for underwater oil and gas production tree pipes to solve the problems mentioned in the background art.

[0004] The technical solution of this utility model to solve the above-mentioned technical problems is as follows:

[0005] A plugging device for underwater oil and gas production tree pipes includes: a plugging body, a metal sealing ring, and a guide plate connected axially in sequence, with an internal retrieval component movably connected to the front end of the plugging body.

[0006] A first annular step is provided at the rear end of the plug body and near the metal sealing ring. A first support ring, a first V-shaped sealing ring, an O-ring, a second V-shaped sealing ring, and a second support ring are sequentially fitted on the first annular step along the axial direction. The end face of the second support ring away from the second V-shaped sealing ring contacts the front end of the metal sealing ring.

[0007] Furthermore, the aforementioned metal sealing ring includes a connecting part, a transition part, and a deformable part connected axially in sequence. The end of the connecting part away from the transition part is threadedly connected to the rear end of the plug body, and the end of the deformable part away from the transition part is threadedly connected to the guide plate. The end face of the deformable part away from the transition part is provided with an annular pressure groove that communicates with the outside.

[0008] The outer diameter of the transition section gradually decreases from the connecting section to the deformable section, and the outer diameter of the deformable section gradually decreases away from the transition section.

[0009] Furthermore, V-shaped grooves are respectively provided on the side of the first support ring near the first V-shaped sealing ring and on the side of the second support ring near the second V-shaped sealing ring.

[0010] Furthermore, the side of the first support ring away from the first V-shaped sealing ring and the side of the second support ring away from the second V-shaped sealing ring are respectively provided with chamfers.

[0011] Furthermore, a mud scraper ring is provided on the outer wall of the aforementioned guide plate.

[0012] Furthermore, the aforementioned internal retrieval assembly includes an internal retrieval neck and an annular cap fitted on the outer wall of the internal retrieval neck. The rear end of the internal retrieval neck is slidably engaged with the inner wall of the front end of the plug body, and the inner wall of the rear end of the plug body is provided with an annular protrusion for limiting the sliding position of the internal retrieval neck. The annular cap is threadedly connected to the front end of the plug body, and the inner wall of the annular cap is provided with a limiting component for limiting the position of the internal retrieval neck. The outer wall of the front end of the internal retrieval neck is provided with a through hole.

[0013] Furthermore, the outer wall of the front end of the aforementioned inner salvage neck is provided with an annular groove for installing an annular pressure cap; the inner wall of the rear end of the annular pressure cap is provided with a limiting groove to block the threaded connection between the main body and the side wall of the limiting groove.

[0014] The annular cap has an inclined hole on its inner front wall that communicates with the interior, and a drain hole that communicates with the inclined hole is provided on the outer front wall of the annular cap in the radial direction.

[0015] The limiting assembly includes a screw, a spring, and a cylindrical pin connected axially in sequence. The screw is threaded into the inlet end of the inclined hole, and the cylindrical pin extends out of the outlet end of the inclined hole and contacts the outer wall of the inner retrieval neck.

[0016] Furthermore, the inlet end of the aforementioned inclined hole faces the front end of the blockage body, and the drain hole corresponds to and is connected to the outlet end of the inclined hole.

[0017] Furthermore, the outer wall of the middle part of the aforementioned plug body is provided with a through groove that communicates with its interior, and a positioning block that matches the rear end of the inner retrieval neck is installed in the through groove. The end of the positioning block is provided with a limiting protrusion to prevent it from falling out of the through groove.

[0018] When the side wall of the annular groove on the inner retrieval neck contacts the inner wall of the annular cap, the outer end face of the positioning block is flush with the outer end face of the block body; when the inner retrieval neck extends into the block body, the outer end face of the positioning block extends out of the through groove.

[0019] Furthermore, the aforementioned limiting protrusion is located inside the through groove and faces the metal sealing ring.

[0020] This utility model has the following beneficial effects:

[0021] 1. The underwater oil and gas production tree pipe plug of this utility model uses a metal sealing ring in conjunction with a first support ring, a first V-shaped sealing ring, an O-ring, a second V-shaped sealing ring, and a second support ring to achieve multiple seals. Furthermore, while achieving a seal, the plug of this utility model can also move up and down inside the working cylinder, and its sealing performance can be maintained even during up and down movement. This makes the retrieval of the plug very simple, convenient, and easy to operate. The internal retrieval component facilitates cooperation with external lowering and retrieval tools, making it easy to carry out lowering and retrieval operations.

[0022] 2. The underwater oil and gas production tree pipe plug of this utility model has a mud scraper ring on the guide plate that provides primary protection for the sealing of the plug, a metal sealing ring as the second level of protection, and a V-shaped sealing ring and an O-ring as the third and fourth levels of protection, thereby achieving multi-level sealing and stable sealing pressure.

[0023] 3. The underwater oil and gas production tree tubing plug of this utility model has a deformable part of the metal sealing ring that matches the annular plane inside the working cylinder. The transition part is used to limit and fix the position of the plug when it is inserted, and the connecting part is used to straighten the plug and prevent it from tilting. During operation, the tubing medium first impacts the guide plate. After the mud scraper on the guide plate fails to seal, the tubing medium enters the annular pressure groove. Under pressure, the deformable part will undergo elastic deformation along its radial outer side, thereby forming a seal and greatly improving the sealing effect.

[0024] 4. The underwater oil and gas production tree pipe plugging device of this utility model has an internal retrieval component with a positioning block. The positioning block is used to cooperate with the inner wall of the working cylinder and can guide the plugging device. Attached Figure Description

[0025] Figure 1 A cross-sectional schematic diagram of a plugging device for oil pipes in subsea oil and gas production trees;

[0026] Figure 2 This is a schematic cross-sectional view of the blockage body.

[0027] Figure 3 This is a cross-sectional view of the metal sealing ring and the guide plate.

[0028] Figure 4 This is a cross-sectional view of the internal salvage component.

[0029] In the diagram: 1. Blocking body; 11. First annular step; 12. First support ring; 13. First V-shaped sealing ring; 14. O-ring; 15. Second V-shaped sealing ring; 16. Second support ring; 17. Annular protrusion; 18. Through groove; 2. Metal sealing ring; 21. Connecting part; 22. Transition part; 23. Deformation part; 24. Annular pressure groove; 3. Guide plate; 4. Internal retrieval assembly; 41. Internal retrieval neck; 411. Through hole; 42. Annular pressure cap; 421. Limiting groove; 43. Inclined hole; 44. Drain hole; 5. Sludge scraper ring; 6. Limiting assembly; 61. Screw; 62. Spring; 63. Cylindrical pin; 7. Positioning block; 71. Limiting protrusion. Detailed Implementation

[0030] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0031] like Figures 1 to 4As shown, this utility model provides a plugging device for underwater oil and gas production tree tubing, including: a plugging body 1, a metal sealing ring 2, and a guide plate 3 connected axially in sequence. In this embodiment, a mud scraper 5 is provided annularly on the outer wall of the guide plate 3, which provides initial sealing for the plugging device; an inner retrieval component 4 is movably connected to the front end of the plugging body 1, and several shaft holes of different sizes are sequentially opened along the axial direction inside the plugging body 1, which are used to cooperate with the outer wall of the inner retrieval component 4 and provide a moving space for the inner retrieval component 4; the inner retrieval component 4 is used to cooperate with external lowering and retrieval tools to facilitate lowering and retrieval operations; a first annular step 11 is provided at the rear end of the plugging body 1 near the metal sealing ring 2, and a first support ring 12, a first V-shaped sealing ring 13, an O-ring 14, a second V-shaped sealing ring 15, and a second support ring 16 are sequentially fitted on the first annular step 11 along the axial direction. The end face of the second support ring 16 away from the second V-shaped sealing ring 15 contacts the front end of the metal sealing ring 2. Multiple first V-shaped sealing rings 13 and second V-shaped sealing rings 15 are provided, and the first V-shaped sealing rings 13 and second V-shaped sealing rings 15 are symmetrical about the O-ring 14. The specific number depends on the length of the first annular step 11 and is not specifically limited here. The first support ring 12, first V-shaped sealing ring 13, O-ring 14, second V-shaped sealing ring 15, and second support ring 16 are used to seal with the external working cylinder. In this embodiment, the first support ring 12 near the first V-shaped sealing ring 13 and the second support ring 16 near the second V-shaped sealing ring 15 are respectively provided with V-shaped grooves for use with the V-shaped sealing rings. The first support ring 12 away from the first V-shaped sealing ring 13 and the second support ring 16 away from the second V-shaped sealing ring 15 are respectively provided with chamfers for easy guidance. This invention provides primary protection for the sealing of the blocker through the scraper ring 5 on the guide plate 3, the metal sealing ring 2 as the second level of protection, and the first V-shaped sealing ring 13, the second V-shaped sealing ring 15, and the O-ring 14 as the third and fourth levels of protection, thereby achieving multi-level sealing and stable sealing pressure.

[0032] Specifically, the metal sealing ring 2 includes a connecting part 21, a transition part 22, and a deformable part 23 connected axially in sequence. The end of the connecting part 21 away from the transition part 22 is threadedly connected to the rear end of the plug body 1. The end face of the connecting part 21 away from the transition part 22 is provided with an internal threaded hole along the axial direction. The rear end of the plug body 1 is provided with an external thread that mates with the internal threaded hole on the connecting part 21. At the same time, the outer wall of the connecting part 21 is also provided with a mounting hole. A set screw is provided in the mounting hole. The set screw is used to further fix the connecting part 21 and the plug body 1. The end of the deformable part 23 away from the transition part 22 is threadedly connected to the guide plate 3, and the end face of the deformable part 23 away from the transition part 22 is provided with an annular pressure groove 24 communicating with the outside; the end face of the deformable part 23 is provided with an internal threaded hole along the axial direction, and the end of the guide plate 3 facing the deformable part 23 is provided with a connecting post. The outer wall of the connecting post is provided with an external thread that mates with the internal threaded hole on the deformable part 23, and there is a gap between the guide plate 3 and the end face of the deformable part 23. The annular pressure groove 24 is located outside the internal threaded hole on the deformable part 23; at the same time, the guide plate 3 is provided with a set screw hole along the axial direction, and the guide plate 3 and the deformable part 23 are further fixed by the set screw; the outer diameter of the transition part 22 gradually decreases from the connecting part 21 to the deformable part 23, and the outer diameter of the deformable part 23 gradually decreases along the direction away from the transition part 22.

[0033] The deformable part 23 of the metal sealing ring 2 matches the annular plane inside the outer working cylinder. The transition part 22 is used to limit and fix the position of the plugger. The connecting part 21 is used to straighten the plugger and prevent it from tilting. During operation, the oil pipe medium first impacts the guide plate 3. After the seal of the mud scraper ring 5 on the guide plate 3 fails, the oil pipe medium enters the annular pressure groove 24. Under the pressure, the deformable part 23 will undergo elastic deformation along its radial outer side, and the conical surface of the deformable part 23 will be tightly attached to the inner wall of the working cylinder, thereby forming a seal and greatly improving the sealing effect.

[0034] like Figure 4 As shown, the internal retrieval assembly 4 includes an internal retrieval neck 41 and an annular pressure cap 42 sleeved on the outer wall of the internal retrieval neck 41. The inner wall of the internal retrieval neck 41 has several shaft holes of different sizes arranged axially, which are used to cooperate with external retrieval tools and lowering tools for normal deployment and retrieval. The outer wall of the front end of the internal retrieval neck 41 has a through hole 411, which is used for draining liquid or venting air, or reducing resistance during installation and lowering. The rear end of the internal retrieval neck 41 is slidably engaged with the inner wall of the front end of the blocking body 1, and the inner wall of the rear end of the blocking body 1 is provided with an annular protrusion 17 for limiting the sliding position of the internal retrieval neck 41. The annular pressure cap 42 is threadedly connected to the front end of the blocking body 1, and the inner wall of the annular pressure cap 42 is provided with a limiting component 6 for limiting the position of the internal retrieval neck 41.

[0035] Specifically, the outer wall of the front end of the inner retrieval neck 41 is provided with an annular groove for installing the annular pressure cap 42. After the annular pressure cap 42 is connected to the front end of the plug body 1, the annular groove can restrict the movement of the inner retrieval neck 41. The inner wall of the rear end of the annular pressure cap 42 is provided with a limiting groove 421. The plug body 1 is threaded to the side wall of the limiting groove 421. The side wall of the limiting groove 421 is provided with an internal thread. The outer wall of the front end of the plug body 1 is provided with an external thread that mates with the internal thread of the side wall of the limiting groove 421 to achieve thread engagement. The inner wall of the front end of the annular pressure cap 42 is provided with an inclined hole 43 that communicates with its interior. The outer wall of the front end of the annular pressure cap 42 is provided radially with a drain hole 44 that communicates with the inclined hole 43. The drain hole 44 is used for draining liquid or venting air, or to reduce resistance during installation and lowering. Furthermore, the inlet end of the inclined hole 43 faces the front end of the plug body 1, and the drain hole 44 corresponds to and communicates with the outlet end of the inclined hole 43.

[0036] The limiting component 6 includes a screw 61, a spring 62, and a cylindrical pin 63 connected axially in sequence. The screw 61 is threaded into the inlet end of the inclined hole 43, and the cylindrical pin 63 extends out of the outlet end of the inclined hole 43 and contacts the outer wall of the inner retrieval neck 41. The inner diameter of the inclined hole 43 is slightly larger than the outer diameter of the cylindrical pin 63, and the inner wall of the inclined hole 43 has an internal thread that matches the screw 61. The inclined hole 43 is used to install the limiting component 6. When the inner retrieval neck 41 gradually enters the blocking body 1, the outer wall of the inner retrieval neck 41 will squeeze the cylindrical pin 63. At this time, the cylindrical pin 63 does not limit the inner retrieval neck 41. When the inner retrieval neck 41 moves into place, the cylindrical pin 63 extends out of the inclined hole 43 under the elastic force of the spring 62. The cylindrical pin 63 can be used to limit the reverse movement of the inner retrieval neck 41.

[0037] The outer wall of the blocking body 1 has annularly spaced through grooves 18 communicating with its interior. A positioning block 7, matching the rear end of the inner retrieval neck 41, is installed within the through groove 18. The inner wall of the positioning block 7 has several steps matching the outer wall of the inner retrieval neck 41. The end of the positioning block 7 has a limiting protrusion 71 to prevent it from falling out of the through groove 18. The limiting protrusion 71 is located inside the through groove 18 and faces the metal sealing ring 2. When the side wall of the annular groove on the inner retrieval neck 41 contacts the inner wall of the annular cap 42, the outer end face of the positioning block 7 is flush with the outer end face of the blocking body 1. When the inner retrieval neck 41 extends into the blocking body 1, the outer end face of the positioning block 7 extends outside the through groove 18. In this embodiment, there are four positioning blocks 7, and the number of through grooves 18 is equal to the number of positioning blocks 7. The positioning block 7 is used to cooperate with the inner wall of the outer working cylinder. When the inner retrieval neck 41 enters the blockage body 1, the positioning block 7 can be pushed out. The positioning block 7 can extend out of the through groove 18, thereby guiding the blocker.

[0038] When using the underwater oil and gas production tree pipe plugging device of this utility model:

[0039] (1) Connect the metal sealing ring 2 to the plugging body 1, connect the guide plate 3 to the metal sealing ring 2, and connect the annular pressure cap 42 and the inner retrieval neck 41 to the plugging body 1.

[0040] (2) Connect the plug after the above connection to the matching insertion tool, and follow the insertion steps of the plug to insert the plug into the pre-set working cylinder inside the underwater oil pipe hanger;

[0041] The internal retrieval neck 41 is connected to the lowering tool and moves into the blockage body 1 during the lowering process, thereby pushing out the positioning block 7 and guiding the movement of the blocker through the positioning block 7;

[0042] (3) Apply pressure from the front end of the plug to ensure that the plug is seated in the pre-set working cylinder inside the underwater oil pipe hanger; under the pressure, the oil pipe medium will gradually enter the annular pressure groove 24 of the metal sealing ring 2, and the deformable part 23 will undergo elastic deformation and then come into close contact with the inner wall of the working cylinder to achieve a hard seal; a soft seal is formed with the cooperation of the first support ring 12, the first V-shaped sealing ring 13, the O-ring 14, the second V-shaped sealing ring 15 and the second support ring 16, thereby forming a multi-stage seal;

[0043] (4) Following the steps of inserting the plug, remove the insertion tool. The plug is successfully positioned in the pre-set working cylinder inside the underwater oil pipe hanger.

[0044] (5) Lower the retrieval device and remove the blocker according to the retrieval procedure of the blocker.

[0045] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A plugging device for underwater oil and gas production tree tubing, characterized in that, include: The blockage body (1), metal sealing ring (2), and guide plate (3) are connected axially in sequence. The front end of the blockage body (1) is movably connected to an internal retrieval assembly (4). A first annular step (11) is provided at the rear end of the plug body (1) and near the metal sealing ring (2). A first support ring (12), a first V-shaped sealing ring (13), an O-ring (14), a second V-shaped sealing ring (15) and a second support ring (16) are sequentially sleeved on the first annular step (11) along the axial direction. The end face of the second support ring (16) away from the second V-shaped sealing ring (15) contacts the front end of the metal sealing ring (2). The metal sealing ring (2) includes a connecting part (21), a transition part (22), and a deformable part (23) connected axially in sequence. The end of the connecting part (21) away from the transition part (22) is threadedly connected to the rear end of the plug body (1). The end of the deformable part (23) away from the transition part (22) is threadedly connected to the guide plate (3). The end face of the deformable part (23) away from the transition part (22) is provided with an annular pressure groove (24) communicating with the outside. The outer diameter of the transition portion (22) gradually decreases from the connecting portion (21) to the deformable portion (23), and the outer diameter of the deformable portion (23) gradually decreases in the direction away from the transition portion (22); The outer wall of the connecting part (21) is also provided with an installation hole, and a set screw is provided in the installation hole. The set screw is used to further fix the connecting part (21) and the plug body (1). The inner retrieval assembly (4) includes an inner retrieval neck (41) and an annular cap (42) sleeved on the outer wall of the inner retrieval neck (41). The rear end of the inner retrieval neck (41) is slidably engaged with the inner wall of the front end of the blocking body (1). The inner wall of the rear end of the blocking body (1) is provided with an annular protrusion (17) for limiting the sliding position of the inner retrieval neck (41). The annular cap (42) is threadedly connected to the front end of the blocking body (1). The inner wall of the annular cap (42) is provided with a limiting component (6) for limiting the position of the inner retrieval neck (41). The outer wall of the front end of the inner retrieval neck (41) is provided with a through hole (411).

2. The underwater oil and gas production tree plugging device according to claim 1, characterized in that, The first support ring (12) near the first V-shaped sealing ring (13) and the second support ring (16) near the second V-shaped sealing ring (15) are respectively provided with V-shaped grooves.

3. The underwater oil and gas production tree plugging device according to claim 2, characterized in that, The first support ring (12) on the side away from the first V-shaped sealing ring (13) and the second support ring (16) on the side away from the second V-shaped sealing ring (15) are respectively provided with chamfers.

4. The underwater oil and gas production tree plugging device according to claim 1, characterized in that, The outer wall of the guide plate (3) is provided with a mud scraping ring (5).

5. The underwater oil and gas production tree plugging device according to claim 1, characterized in that, The front outer wall of the inner retrieval neck (41) is provided with an annular groove for installing the annular cover (42); the rear inner wall of the annular cover (42) is provided with a limiting groove (421), and the plug body (1) is threadedly connected to the side wall of the limiting groove (421). The annular cap (42) has an inclined hole (43) communicating with its interior on the inner wall of the front end, and a drain hole (44) communicating with the inclined hole (43) is provided on the outer wall of the front end of the annular cap (42) in the radial direction. The limiting component (6) includes a screw (61), a spring (62) and a cylindrical pin (63) connected axially in sequence. The screw (61) is threaded to the inlet end of the inclined hole (43), and the cylindrical pin (63) extends out of the outlet end of the inclined hole (43) and contacts the outer wall of the inner retrieval neck (41).

6. The underwater oil and gas production tree plugging device according to claim 5, characterized in that, The inlet end of the inclined hole (43) faces the front end of the blockage body (1), and the drain hole (44) corresponds to and is connected to the outlet end of the inclined hole (43).

7. The underwater oil and gas production tree plugging device according to claim 5, characterized in that, The middle outer wall of the blocking body (1) is provided with a through groove (18) that communicates with its interior. A positioning block (7) that matches the rear end of the inner retrieval neck (41) is installed in the through groove (18). The end of the positioning block (7) is provided with a limiting protrusion (71) to prevent it from falling out of the through groove (18). When the side wall of the annular groove on the inner retrieval neck (41) contacts the inner wall of the annular cap (42), the outer end face of the positioning block (7) is flush with the outer end face of the blocking body (1); when the inner retrieval neck (41) extends into the blocking body (1), the outer end face of the positioning block (7) extends to the outside of the through groove (18).

8. The underwater oil and gas production tree plugging device according to claim 7, characterized in that, The limiting protrusion (71) is located inside the through groove (18) and faces the metal sealing ring (2).

Images