High-pressure self-sealing leak-proof oil production wellhead device

Abstract

The present application relates to oil well mouth technical field, specifically relates to high pressure self-sealing leakproof oil production well mouth device, including oil well body, the outer wall of oil well body is fixedly connected with base, the top of oil well body is equipped with well lid, the upper surface of base is equipped with pressing mechanism, the pressing mechanism includes fixed base, the fixed base is fixedly connected at one end close to well lid, the end away from base of fixed base is fixedly connected with limit box, the inner wall of limit box is provided with groove, the inner wall of groove is fixedly connected with slide rail, the outer wall of slide rail is slidably connected with slide rod, the one end of slide rod is provided with slide groove for sliding on the outer wall of slide rail. The combination of screw rod, slide rail and limit groove makes the pressing plate exert continuous pressure, even if the downhole pressure fluctuates, the pressing plate always presses the well lid tightly because the screw rod cannot be pushed back reversely, thereby eliminating the possibility of opening the gap due to pressure rise.

Description

Technical Field

[0001] This invention relates to the field of oil wellhead technology, specifically to a high-pressure self-sealing leak-proof oil wellhead device. Background Technology

[0002] With the increasing demand for energy, oil extraction has become a crucial source of energy supply. As oilfield development and production extend, the workload for various well-related processes is increasing. Wellhead equipment, especially production wellhead equipment, is vital for ensuring normal oil well production. While there are many types and structures, their shortcomings become increasingly apparent with repeated use. Components frequently fail, maintenance is difficult, and the lack of effective sealing structures makes them prone to leaks. They cannot reliably perform multiple processes, have short service lives, and increase production costs. Furthermore, in the event of a blowout, existing wellhead sealing devices cannot release pressure promptly, leading to oil waste, environmental pollution, and compromised personnel safety.

[0003] Patent document CN215292419U discloses a sealing device, specifically an oil wellhead sealing device. It includes a buffer chamber, with an upper pipe and a lower pipe fixed to its upper and lower ends respectively, communicating with it. An inner ring is fixed inside the buffer chamber, and an inner sleeve is fixed inside the inner ring. A smooth rod passes through the inner sleeve and is slidably sealed to it. An inner concentric conical sleeve is fixed to the lower end of the inner sleeve, with the smooth rod passing through it. A gap is provided between the inner conical sleeve and the bottom plate of the buffer chamber. An outer conical sleeve is fitted outside the inner conical sleeve, with its lower end fixed to the bottom plate of the buffer chamber. A gap is provided between the upper end of the outer conical sleeve and the inner ring, and a gap is provided between the inner edge of the outer conical sleeve and the outer edge of the inner conical sleeve. A connecting pipe is fixed to the buffer chamber and communicates with it. This invention can promptly release pressure in the event of a blowout, thereby avoiding oil waste and environmental pollution, ensuring the safety of workers, reducing costs, decreasing downhole accidents, and improving oilfield production efficiency.

[0004] Although the aforementioned application documents state that in the event of a blowout, pressure can be released in a timely manner to avoid oil waste and environmental pollution, ensure the safety of personnel, reduce costs, decrease downhole accidents, and improve oilfield production efficiency, the bolt preload is fixed during use. When the pressure inside the well increases, the medium will attempt to open the sealing surface. Once the opening force generated by the well pressure exceeds the bolt preload, the sealing surface will be pushed open with a small gap, leading to instantaneous leakage.

[0005] Therefore, a high-pressure self-sealing leak-proof oil wellhead device is proposed to solve the problems mentioned above. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a high-pressure self-sealing leak-proof oil wellhead device, thereby solving the problem that when the bolt preload is fixed during use, the medium will attempt to open the sealing surface when the well pressure increases. Once the opening force generated by the well pressure exceeds the bolt preload, the sealing surface will be pushed open with a small gap, leading to instantaneous leakage.

[0007] To achieve the above objectives, the present invention provides the following technical solution: including an oil well body, a base fixedly connected to the outer wall of the oil well body, a well cover mounted on the top of the oil well body, and a pressing mechanism mounted on the upper surface of the base; The pressing mechanism includes a fixed base, which is fixedly connected to one end near the manhole cover. A limit box is fixedly connected to the end of the fixed base away from the base. A groove is formed in the inner wall of the limit box, and a slide rail is fixedly connected to the inner wall of the groove. A slide rod is slidably connected to the outer wall of the slide rail. One end of the slide rod has a groove for sliding on the outer wall of the slide rail. A support rod is fixedly connected to the bottom of the slide rod. A connecting rod is hinged to the front of the support rod. A fixed rod is fixedly connected to the end of the connecting rod away from the support rod. A pressure plate is fixedly connected to the front of the fixed rod. A drive assembly for driving the pressure plate to descend is assembled on the top of the base. The pressure plate is cast in one piece, which improves the overall integrity. There are no internal interfaces, eliminating the weakness problem at the interface. No assembly is required; it can be directly installed, which facilitates production, manufacturing, and maintenance. It reduces the number of parts and steps in the assembly process, reduces assembly costs and time, reduces connection points and joints, reduces the risk of loosening or failure between parts, enhances the structural strength and stability of the overall component, and improves the long service life of the product.

[0008] Preferably, the drive assembly includes a rotating rod and a pulley, the rotating rod being rotatably connected to the front of the pressure plate via a bearing, and the pulley being fixedly connected to the outer wall of the arc-shaped surface of the rotating rod.

[0009] Preferably, a vertical plate is fixedly connected to the upper surface of the limiting box, a limiting groove is formed on the front of the vertical plate, and the pulley is slidably connected to the inner wall of the limiting groove.

[0010] Preferably, a fixing plate is fixedly connected to the back of the vertical plate, and a lead screw is threaded through the side of the fixing plate. The extension end of the lead screw extends to the left and is fixedly connected to the side of the support rod.

[0011] Preferably, a horizontal plate is fixedly connected to the side of the support rod, a limit block is fixedly connected to the upper surface of the horizontal plate, and the pressure plate is slidably connected to the outer wall of the limit block.

[0012] Preferably, the slide rail is T-shaped, the slide groove is T-shaped, and there are two slide rods, which are mirror images of the upper and lower surfaces of the support rod.

[0013] Preferably, the limiting block has a cross-shaped overall shape, and the end of the pressure plate that contacts the well cover has an arc shape. The limiting block is cast in one piece, which improves the integrity. There are no internal interfaces, so there are no weaknesses at the interfaces. No assembly is required, and it can be installed directly, which facilitates production and maintenance. It reduces the number of parts and steps in the assembly process, reduces assembly costs and time, reduces connection points and joints, reduces the risk of loosening or failure between parts, enhances the structural strength and stability of the overall component, and improves the long service life of the product.

[0014] Preferably, the limiting groove has an overall L-shaped shape and is mirror-image positioned.

[0015] Preferably, the vertical plate has a horizontal groove on its front side, and a movable block is fixedly connected to the front side of the horizontal groove, and the movable block is slidably connected to the inner wall of the horizontal groove.

[0016] Compared with the prior art, the present invention provides a high-pressure self-sealing leak-proof oil wellhead device, which has the following beneficial effects: 1. By combining the lead screw with the slide rail and the limiting groove, the pressure plate applies continuous pressure. Even if the downhole pressure fluctuates, the pressure plate will always firmly press the well cover down because the lead screw cannot be pushed back in the opposite direction, thus eliminating the possibility of the gap being opened due to increased pressure.

[0017] Second, the movement trajectory of the pressure plate is strictly regulated through the cooperation of the L-shaped limiting groove and the pulley. It first approaches horizontally and then presses down vertically, ensuring that the pressure plate can press vertically and accurately on the side of the manhole cover, rather than cutting across it at an angle. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a front view of part of the structure of the present invention; Figure 3 This is a schematic diagram of the left side of a portion of the structure of the present invention; Figure 4 This is a top view of part of the structure of the present invention; Figure 5 For the present invention Figure 2 Enlarged structural diagram at point A in the middle; Figure 6 For the present invention Figure 3 Enlarged structural diagram at point B.

[0019] In the diagram: 1. Oil well body; 2. Base; 3. Pressing mechanism; 31. Fixed seat; 32. Screw rod; 33. Sliding rod; 34. Sliding groove; 35. Limiting box; 36. Sliding rail; 37. Support rod; 38. Connecting rod; 39. Fixed rod; 310. Pulley; 311. Rotating rod; 312. Limiting groove; 313. Pressure plate; 314. Limiting block; 315. Horizontal plate; 316. Moving block; 317. Horizontal groove; 4. Well cover. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example: Please see Figure 1 - Figure 6 The high-pressure self-sealing leak-proof oil wellhead device in this embodiment includes an oil well body 1, a base 2 fixedly connected to the outer wall of the oil well body 1, a well cover 4 mounted on the top of the oil well body 1, and a pressing mechanism 3 mounted on the upper surface of the base 2. The pressing mechanism 3 includes a fixed base 31, which is fixedly connected to one end near the manhole cover 4. A limit box 35 is fixedly connected to the end of the fixed base 31 away from the base 2. A groove is provided on the inner wall of the limit box 35. A slide rail 36 is fixedly connected to the inner wall of the groove. A slide rod 33 is slidably connected to the outer wall of the slide rail 36. A groove 34 for sliding on the outer wall of the slide rail 36 is provided at one end of the slide rod 33. A support rod 37 is fixedly connected to the bottom of the slide rod 33. A connecting rod 38 is hinged to the front of the support rod 37. A fixed rod 39 is fixedly connected to the end of the connecting rod 38 away from the support rod 37. A pressure plate 313 is fixedly connected to the front of the fixed rod 39. A drive assembly for driving the pressure plate 313 to descend is assembled on the top of the base 2. The entire pressing mechanism 3 is mounted on the base 2 of the oil well body 1 via the fixed seat 31. The slide rod 33 slides on the slide rail 36 via the slide groove 34 without shaking or deflection. When the drive component works, it pushes the pressure plate 313. The pressure plate 313 pulls the connecting rod 38 via the fixed rod 39. The connecting rod 38 pulls the support rod 37, thereby driving the slide rod 33 to move. The pressure plate 313 is cast in one piece, which improves the integrity. There are no internal interfaces, so there are no weak points at the interfaces. No assembly is required. It can be installed directly, which is convenient for production and maintenance. It reduces the number of parts and steps in the assembly process, reduces assembly costs and time, reduces connection points and joints, reduces the risk of loosening or failure between parts, enhances the structural strength and stability of the overall component, and improves the long service life of the product.

[0022] The drive assembly includes a rotating rod 311 and a pulley 310. The rotating rod 311 is rotatably connected to the front of the pressure plate 313 via a bearing, and the pulley 310 is fixedly connected to the outer wall of the arc-shaped surface of the rotating rod 311. When the drive mechanism pushes the pressure plate 313, the pulley 310 will roll along a specific track. Without the pulley 310, the pressure plate 313 would directly rub against the limit box 35, making operation very difficult and prone to jamming. The introduction of the pulley 310 makes the movement of the pressure plate 313 smoother and reduces operating resistance.

[0023] A vertical plate is fixedly connected to the upper surface of the limiting box 35. A limiting groove 312 is opened on the front of the vertical plate. The pulley 310 is slidably connected to the inner wall of the limiting groove 312. The limiting groove 312 forcibly restricts the rolling path of the pulley 310, ensuring that the pressure plate 313 will not sway back and forth or left and right during the descent, but will move according to the trajectory of the limiting groove 312, ensuring that the pressure plate 313 can accurately press on the side of the manhole cover 4.

[0024] A fixing plate is fixedly connected to the back of the vertical plate. A lead screw 32 is threaded through the side of the fixing plate. The extension end of the lead screw 32 extends to the left and is fixedly connected to the side of the support rod 37. When the operator rotates the lead screw 32, the rotational motion is converted into linear motion of the lead screw 32 due to the threaded engagement between the lead screw 32 and the fixing plate. This pushes and pulls the support rod 37. The pressure downhole cannot push the lead screw 32 to rotate in the opposite direction, thus achieving mechanical anti-loosening, which is safer than simple bolt tightening.

[0025] A horizontal plate 315 is fixedly connected to the side of the support rod 37. A limit block 314 is fixedly connected to the upper surface of the horizontal plate 315. The pressure plate 313 is slidably connected to the outer wall of the limit block 314. When the pressure plate 313 moves back and forth, it is also constrained by the limit block 314. The pressure plate 313 has a matching groove that is stuck on the limit block 314. The cross-shaped limit block 314 can prevent the pressure plate 313 from twisting or deflecting when under force, ensuring that the pressure plate 313 always faces the manhole cover 4 at the correct angle arc, and avoiding leakage caused by uneven force on the manhole cover 4 due to the tilt of the pressure plate 313.

[0026] The slide rail 36 is T-shaped, the slide groove 34 is T-shaped, and there are two slide rods 33, which are mirror images of the upper and lower surfaces of the support rod 37. The T-shaped structure can withstand forces in multiple directions, including up and down and left and right, to prevent the support rod 37 from tilting. The double slide rods 33 make the pressure plate 313 more balanced in terms of force and move more smoothly, improving the durability of the mechanism under high pressure vibration environment. At the same time, the upper and lower slide rods 33 constrain the support rod 37.

[0027] The limiting block 314 has a cross-shaped overall shape, and the end of the pressure plate 313 that contacts the manhole cover 4 is arc-shaped, which can achieve surface contact with the outer circle of the manhole cover 4 to increase the contact area and avoid concentrating huge pressure on one point to damage the surface of the manhole cover 4. At the same time, the clamping force is more uniform and the sealing effect is better. The limiting block 314 is cast in one piece, which improves the integrity. There are no internal interfaces, so there are no weak points at the interface. No assembly is required, and it can be installed directly, which facilitates production, manufacturing and maintenance. It reduces the number of parts and steps in the assembly process, reduces assembly costs and time, reduces connection points and joints, reduces the risk of loosening or failure between parts, enhances the structural strength and stability of the overall component, and improves the long service life of the product.

[0028] The limiting groove 312 has an overall L-shaped shape. The limiting groove 312 is mirrored. In the initial stage, the pressure plate 313 moves closer to the well cover 4. In the final stage, a huge downward squeezing force is generated through the L-shaped bend.

[0029] A horizontal groove 317 is provided on the front of the vertical plate. A movable block 316 is fixedly connected to the front of the horizontal groove 317. The movable block 316 is slidably connected to the inner wall of the horizontal groove 317. When the lead screw 32 pushes the support rod 37 to move, the horizontal plate 315 on the support rod 37 slides synchronously in the horizontal groove 317 with the movable block 316. The support rod 37 is not only fixed to the rear by the slide rod 33, but also connected to the front vertical plate by the movable block 316 and the horizontal groove 317. It can withstand huge blowout pressure, and the structure is more stable and will not deform.

[0030] The working principle of the above embodiment is as follows: When the pressing mechanism 3 is in the released state, the pressure plate 313 is away from the manhole cover 4. The manhole cover 4 is initially sealed by its own weight and bolts. The operator starts to rotate the screw 32. The screw 32 rotates and pushes the support rod 37 to move towards the manhole cover 4. When the support rod 37 moves, it drives the upper and lower slide rods 33 to slide smoothly along the T-shaped slide rail 36 to ensure that the whole does not shake. At the same time, the support rod 37 drives the pressure plate 313 to move through the connecting rod 38 and the fixing rod 39. The pulley 310 on the pressure plate 313 rolls along the L-shaped limiting groove 312 on the vertical plate. The L-shaped track guides the pressure plate 313 to move. Plate 313 first approaches the manhole cover 4, and then as the screw 32 continues to advance, the pulley 310 generates a downward component force at the L-shaped bend, forcing the pressure plate 313 to press down on the manhole cover 4. At this time, the arc-shaped pressure plate 313 fits tightly against the top of the manhole cover 4, applying a huge downward preload. During the pressing process, the cooperation between the cross-shaped limit block 314 and the transverse groove 317 with the moving block 316 ensures that the pressure plate 313 will not twist and always maintains the best pressing posture. The thread self-locking characteristic of the screw 32 makes it impossible to push the screw 32 back even if there is high pressure in the well pushing the manhole cover 4 upward.

[0031] The installation, connection, or setting methods disclosed in this embodiment are all common mechanical connection methods. As long as they can achieve their beneficial effects, they can be implemented. Therefore, this embodiment will not elaborate on their specific structural composition and working principle.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-pressure self-sealing leak-proof oil wellhead device, characterized in that: The well body (1) is included, and a base (2) is fixedly connected to the outer wall of the well body (1). A well cover (4) is installed on the top of the well body (1), and a pressing mechanism (3) is installed on the upper surface of the base (2). The pressing mechanism (3) includes a fixed base (31), which is fixedly connected to one end near the manhole cover (4). A limit box (35) is fixedly connected to the end of the fixed base (31) away from the base (2). A groove is provided on the inner wall of the limit box (35). A slide rail (36) is fixedly connected to the inner wall of the groove. A slide rod (33) is slidably connected to the outer wall of the slide rail (36). A groove (34) for sliding on the outer wall of the slide rail (36) is provided at one end of the slide rod (33). A support rod (37) is fixedly connected to the bottom of the slide rod (33). A connecting rod (38) is hinged to the front of the support rod (37). A fixed rod (39) is fixedly connected to the end of the connecting rod (38) away from the support rod (37). A pressure plate (313) is fixedly connected to the front of the fixed rod (39). A drive assembly for driving the pressure plate (313) to descend is assembled on the top of the base (2).

2. The high-pressure self-sealing leak-proof oil wellhead device according to claim 1, characterized in that: The drive assembly includes a rotating rod (311) and a pulley (310). The rotating rod (311) is rotatably connected to the front of the pressure plate (313) via a bearing, and the pulley (310) is fixedly connected to the outer wall of the arc-shaped surface of the rotating rod (311).

3. The high-pressure self-sealing leak-proof oil wellhead device according to claim 2, characterized in that: A vertical plate is fixedly connected to the upper surface of the limiting box (35), and a limiting groove (312) is opened on the front of the vertical plate. The pulley (310) is slidably connected to the inner wall of the limiting groove (312).

4. The high-pressure self-sealing leak-proof oil wellhead device according to claim 3, characterized in that: A fixing plate is fixedly connected to the back of the vertical plate, and a screw rod (32) is threaded through the side of the fixing plate. The extension end of the screw rod (32) extends to the left and is fixedly connected to the side of the support rod (37).

5. The high-pressure self-sealing leak-proof oil wellhead device according to claim 4, characterized in that: The support rod (37) is fixedly connected to a horizontal plate (315) on its side. A limit block (314) is fixedly connected to the upper surface of the horizontal plate (315). The pressure plate (313) is slidably connected to the outer wall of the limit block (314).

6. The high-pressure self-sealing leak-proof oil wellhead device according to claim 1, characterized in that: The slide rail (36) is T-shaped, the slide groove (34) is T-shaped, and there are two slide rods (33), which are mirror images of the upper and lower surfaces of the support rod (37).

7. The high-pressure self-sealing leak-proof oil wellhead device according to claim 5, characterized in that: The limiting block (314) has a cross-shaped overall shape, and the end of the pressure plate (313) that contacts the well cover (4) has an arc shape.

8. The high-pressure self-sealing leak-proof oil wellhead device according to claim 3, characterized in that: The limiting groove (312) has an overall L-shaped shape, and the limiting groove (312) is mirrored.

9. The high-pressure self-sealing leak-proof oil wellhead device according to claim 8, characterized in that: The vertical plate has a horizontal groove (317) on its front side, and a movable block (316) is fixedly connected to the front side of the horizontal groove (317). The movable block (316) is slidably connected to the inner wall of the horizontal groove (317).

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