Turned ball seat and method of downhole construction

Abstract

The application provides a turnover ball seat, which comprises a body, a storage groove formed on the inner wall of the body, an inner sleeve nested on the upper end of the body, and a ball seat body fixed in the inner sleeve through a shear pin, wherein a guide rod is arranged below the ball seat body, a guide mechanism matched with the guide rod is arranged in the body, the ball seat body and the pressure ball rotate and shrink into the storage groove under the traction of the guide rod and the guide mechanism, so that a flow position is left. In addition, the application further provides a downhole construction method.

Description

Technical Field

[0001] This invention relates to the field of downhole cementing tools for oil wells, and more specifically to a rotating ball bearing and a downhole construction method. Background Technology

[0002] Currently, for vertical or deviated wells using single-pass cementing, existing cementing technology typically involves placing the ball seat below the cementing tools that require action, such as packers, tailpipe hangers, and restraining subs, and above cementing tool accessories that do not require action, such as floats and float shoes. By dropping a suitably sized sulfide metal ball, its own weight causes it to fall smoothly into the ball seat opening and engage with the inner conical surface of the ball seat. After engagement, the tubing pressure increases, and when the internal pressure reaches the designed value, the cementing tools above the ball seat will perform the intended action. Continued pressure then forces the sulfide metal ball to puncture the ball seat pin, allowing it to fall into the bottom recovery cage, completing one cementing operation. It is worth noting that with existing ball seat technology, a drilling run is required before the next operation to remove the ball seat and the sulfide ball from the bottom recovery cage. This undoubtedly prolongs the operation time and increases production costs.

[0003] Therefore, it is desirable to provide a method for rotating the ball seat and downhole construction in this field to solve the technological problem of needing to separately run drill strings to remove the ball seat and other accessories at the cementing construction site, thereby saving construction time and costs. Summary of the Invention

[0004] The purpose of this invention is to propose a rotating ball seat and a downhole construction method, which can solve the technical problem of needing to separately run drilling tools to drill and remove ball seats and other accessories at the cementing construction site, thereby saving construction time and costs and ensuring the safety and reliability of engineering operations.

[0005] According to a first aspect of the invention, a flip ball seat is provided, comprising a body, wherein a storage groove is formed on the inner wall of the body. The inner sleeve nested at the upper end of the main body, and The ball seat is fixed in the inner sleeve by a shear pin. A guide rod is provided below the ball seat body, and the flip ball seat includes a guide mechanism disposed within the body and adapted to the guide rod. The ball is thrown and pressed to cut the shear pin. The ball seat and the pressed ball rotate and retract into the storage tank under the traction of the guide rod and the guide mechanism, thereby making room for the flow.

[0006] In one embodiment, the guiding mechanism further includes a guide chassis fixed to the inner wall of the body, and a guide groove formed on the guide chassis in an arcuate configuration.

[0007] In one embodiment, the guiding mechanism further includes a first connecting rod connected to the guide rod, a second connecting rod adapted to the guide groove, and springs respectively abutting against the first connecting rod and the second connecting rod. In this configuration, the second link compresses the spring in its initial state and is embedded within the first link.

[0008] In one embodiment, an anti-swing groove is provided on the inner wall of the body, the end hole of the guide groove coincides with the anti-swing groove, and the second link is configured to extend through the end hole under the action of the spring to lock with the anti-swing groove.

[0009] In one embodiment, a buffer pad for bearing pressure on the second connecting rod is provided at the end of the guide groove. In one embodiment, the guide rod is configured to be flat and laterally fixed to the lower end face of the ball seat.

[0010] In one embodiment, a transition plane is formed on the side of the storage tank near the inner sleeve to guide the ball seat body into it.

[0011] In one embodiment, the guide chassis is secured to the inner wall of the body by at least four set screws.

[0012] According to a second aspect of the present invention, a downhole construction method is provided, which utilizes a rotating ball seat as described above, comprising the following: S1. Throw the ball and pressurize until the critical action pressure is reached so that the setting tool is set in the well; S2. Continue to pressurize until the shear pin is cut off. The ball seat and the pressurized ball rotate and retract into the storage tank under the traction of the guide rod and the guide mechanism, thereby making room for the flow.

[0013] In one embodiment, in step S2, the ball seat rotates 90°.

[0014] Compared with the prior art, the advantages of the present invention are as follows: This invention solves the technological challenge of separately running drill strings and other accessories such as drilling balls into cementing sites, thereby saving construction time and costs while ensuring the safety and reliability of the operation. This device not only creates a pressure-locking environment within the well using the pressure-locking ball and the ball seat to complete the pressure-locking / sealing operation, but also rotates the ball seat 90° counterclockwise along the guide groove under the traction of the guide rod and guide mechanism, causing the ball seat and pressure-locking ball to retract into the storage tank, thus freeing up the flow space. Therefore, this device eliminates the need for drilling after cementing and does not affect the next operation, effectively improving downhole operation efficiency and reducing production costs. Attached Figure Description

[0015] The present invention will now be described in detail with reference to the accompanying drawings.

[0016] Figure 1 The schematic diagram illustrates the structure of the flip ball seat according to the present invention.

[0017] Figure 1a The illustration schematically shows the state of the rotating ball seat after it has been rotated according to the present invention.

[0018] Figure 1b for Figure 1a A partial sectional view.

[0019] Figure 2 The internal structure of the body according to the invention is schematically shown.

[0020] Figure 3 The schematic diagram illustrates the structure of the central guide chassis of the flip ball seat according to the present invention.

[0021] Figure 4 The diagram illustrates the working relationship between the first link, the second link, and the spring.

[0022] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not drawn to scale. Detailed Implementation

[0023] To make the technical solutions and advantages of the present invention clearer, exemplary embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not an exhaustive list of all embodiments. Furthermore, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0024] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0025] In this invention, unless otherwise explicitly specified and limited, the terms “installation,” “connection,” “linking,” “fixing,” etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components.

[0026] Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0027] Current ball-and-socket technology requires a drilling run to remove the ball-and-socket body and sulfide-filled pressure balls from the bottom cage before each subsequent well operation. However, with the development of more and more deep and ultra-deep wells, higher demands are being placed on cementing operations. Typically, to save time and costs in cementing work, it is no longer necessary to separately drill down the ball-and-socket assembly and other cementing accessories. This device can be flipped to create a flow path, eliminating the need for drilling after cementing and without affecting subsequent well operations, effectively improving downhole efficiency and reducing production costs.

[0028] The invention will now be further described with reference to the accompanying drawings.

[0029] Figure 1 A schematic cross-sectional view of the inverted ball seat according to the present invention is shown.

[0030] like Figure 1 As shown, according to a first aspect of the present invention, a flip ball seat 100 is provided, mainly comprising a body 10, an inner sleeve 11 nested in the upper end of the body 10, and a ball seat body 12 concentrically arranged in the inner sleeve 11. Preferably, the ball seat body 12 is fixedly mounted on the inner sleeve 11 by a shear pin 121 in the initial state. A guide rod 14 is provided below the ball seat body 12, and the flip ball seat 100 further includes a guide mechanism disposed within the body 10 and adapted to the guide rod 14.

[0031] exist Figures 1 to 1aIn the process shown, the ball-launching pressure is first applied using a setting / sealing tool, followed by pressure application to shear the shear pin 121. This allows the ball seat 12 to rotate counter-clockwise under the traction of the guide rod 14 and the guide mechanism, enabling it to retract smoothly into the storage tank 101 of the main body 10 along with the pressure ball 15. This further frees up the flow space, providing sufficient downhole movement space for the next operation. Because this device can retract into the storage tank 101, it can still free up the flow space even after dismantling following cementing, thus ensuring that the next operation is not affected.

[0032] Figure 3 The schematic diagram illustrates the structure of the central guide chassis of the flip ball seat according to the present invention.

[0033] In one embodiment, such as Figure 1 As shown, the guiding mechanism also includes a guide base 21 fixed to the inner wall of the body 10, and a guide groove 22 formed on the guide base 21. Preferably, the guide groove 22 is constructed as follows: Figure 3 The 1 / 4 ring structure provides an accurate movement path for the ball seat 12, thus ensuring that the ball seat 12 can accurately enter the storage tank 101 after the flipping motion is completed.

[0034] In this invention, a square planar structure is formed on the side end face of the body 10 for fixing the guide chassis 21. Preferably, as shown... Figure 1 As shown, the guide base 21 is fixed to the planar structure of the body 10 by at least four set screws 26. It is worth noting that each set screw 26 has high compressive strength, so it can effectively withstand the thrust generated by the ball seat 12 during the flipping motion, thereby making it easier to ensure that the ball seat 12 smoothly enters the storage tank 101.

[0035] In such Figure 1 In the illustrated embodiment, the guide rod 14 is configured to be flat and laterally fixed to the lower end face of the ball seat 12. In such... Figure 1b In the illustrated embodiment, the guide rod 14 is actually fixedly installed at the bottom of the lower end face of the ball seat 12, so that the flow position can be more easily made open after the ball seat 12 completes the flipping movement, so as to ensure that the device does not need to be drilled out after cementing and does not affect the next opening operation.

[0036] Because the overall size of the guiding mechanism is small, and the gap between the guide rod 14 and the guide base 21 is only 3% to 5% of the inner diameter of the body 10, the overall structure consisting of the ball seat 12, the guiding mechanism, and the guide base 21 occupies at most 5% of the flow channel of the body 10 after the flipping motion is completed. Therefore, this application, by retracting the ball seat and the pressure-retaining ball into the storage tank, frees up a larger flow space. Thus, after cementing, there is no need for drilling or removal, nor does it affect the next operation, effectively improving downhole operation efficiency and reducing production costs.

[0037] Figure 4 The diagram illustrates the working relationship between the first link, the second link, and the spring.

[0038] In one embodiment, such as Figure 1 and 4 As shown, the guiding mechanism also includes a first link 23, a second link 24, and a spring 25. The first link 23 is arranged perpendicularly to the guide rod 14 and the two are fixedly connected; the end of the second link 24 away from the first link 23 is embedded in the guide groove 22, and the second link 24 can slide in the guide groove 22, thereby playing the role of traction ball seat 12; the spring 25 is sleeved on the outside of the first link 23 and the second link 24, and the two ends of the spring 25 abut against the first link 23 and the second link 24 axially, respectively.

[0039] In the initial state, the second link 24 will compress the spring 25 under the action of the guide groove 22 and partially embed itself into the first link 23, so as to shorten the total length of the first link 23 and the second link 24.

[0040] Figure 2 The internal structure of the body according to the invention is schematically shown.

[0041] In one embodiment, such as Figure 2 As shown, an anti-swing groove 13 is provided on the inner wall of the main body 10. The guide base 21 is installed above the anti-swing groove 13, and the end hole 221 of the guide groove 22 coincides with the anti-swing groove 13 in the radial direction. Therefore, after the ball seat 12 rotates counterclockwise under the traction of the guide rod 14 and the guide mechanism, the second connecting rod 24 can first enter the end hole 221, and then extend through the end hole 221 and enter the anti-swing groove 13 under the elastic force of the spring 25. This locks the second connecting rod 24 with the anti-swing groove 13, thereby effectively limiting the ball seat 12 in the storage tank 101, so that the device does not need to be drilled after cementing and does not affect the next operation.

[0042] In this invention, a buffer pad (not shown) is provided at the end of the guide groove 22, that is, the buffer pad is arranged near the end hole 221. Thus, after the ball seat 12 moves at high speed along the direction of the guide groove 22 under the action of the pressure, the buffer pad can effectively buffer the movement, and at the same time, it can also ensure that the second connecting rod 24 smoothly enters the anti-backswing hole groove 13 to achieve an effective locking function.

[0043] In this invention, a transition plane 16 is formed on the side of the storage groove 101 near the inner sleeve 11. Therefore, during the rotation of the ball seat 12, the pressure ball 15 can fully contact the transition plane 16, so that the ball seat 12 can slide more easily into the storage groove 101, thereby achieving rapid contraction of the ball seat 12 and the pressure ball 15.

[0044] In one embodiment, the inner sleeve 11 has an external thread on its outer side and an internal thread on its inner side, thus the inner sleeve 11 and the body 10 are threaded together, ensuring sufficient pressure-bearing capacity. Furthermore, sealing rings are provided between the inner sleeve 11, the body 10, and the ball seat 12, further enhancing the sealing effect.

[0045] In one embodiment, the upper and lower ends of the body 10 can be provided with M-type straight threads to be fixedly connected to the upper and lower inner tubes. Alternatively, depending on the usage requirements, the upper and lower ends of the body 10 can be machined into sleeve threads, achieving the same technical effect of direct connection with the upper and lower inner tubes.

[0046] In this invention, the pressure-retaining ball 15 is constructed as a vulcanized pressure-retaining ball and is a non-connecting component. It is only deployed to the wellhead when the ball seat body 12 needs to be activated. Preferably, the inner core of the pressure-retaining ball 15 is a metal structure, and the outer skin is vulcanized rubber. Therefore, after it comes into contact with the ball seat body 12, it can form a sealed connection with it through the vulcanized rubber, thereby helping to create a pressure-retaining environment.

[0047] According to a second aspect of the present invention, a downhole construction method is provided, which utilizes a rotating ball seat as described above, comprising the following: First, connect the upper and lower ends of the assembled flip ball seat to the inner tubing string or casing, and then put it into the well.

[0048] Preferably, the position of the inverted ball seat in the tubing should be above the float shoe and float clamp, and simultaneously below the setting / sealing tool, to facilitate pressure setting / sealing.

[0049] Then, the pressure-holding ball 15 is dropped above the wellhead. As the circulating drilling fluid reaches the position, the pressure-holding ball 15 comes into contact with the ball seat body 12. When the pressure reaches the critical operating pressure, the setting / sealing tool is activated to achieve the setting / sealing function.

[0050] Finally, continue to pressurize until the shear pin 121 is cut off. The ball seat 12 tends to slide downwards, so that it can rotate 90 degrees counterclockwise along the trajectory of the guide groove 22 under the traction of the guide rod 14 and the guide mechanism. This causes the ball seat 12 and the pressurized ball 15 to retract into the storage tank 101, thereby making room for the flow.

[0051] Preferably, the second connecting rod 24 can first enter the end hole 221, and then extend through the end hole 221 and enter the anti-swing groove 13 under the elastic force of the spring 25, so as to lock the second connecting rod 24 with the anti-swing groove 13, thereby effectively limiting the ball seat body 12 in the storage tank 101, so that the device does not need to be drilled after cementing and does not affect the next opening operation.

[0052] Preferably, after the ball seat 12 moves at high speed along the direction of the guide groove 22 under the pressure, it can effectively buffer the movement through the buffer pad, and at the same time ensure that the second link 24 can smoothly enter the anti-swing hole groove 13 to achieve an effective locking function.

[0053] Compared with existing technologies, the advantages of this invention are: This invention solves the technological challenge of separately running drill strings and other accessories such as drilling balls into cementing sites, thereby saving construction time and costs while ensuring the safety and reliability of the operation. This device not only creates a pressure-locking environment within the well via the pressure-locking ball 15 and the ball seat body 12 to complete the pressure-locking / sealing operation, but also, under the traction of the guide rod 14 and the guide mechanism, rotates 90° counterclockwise along the trajectory of the guide groove 22 to flip the ball seat body 12, causing the ball seat body 12 and the pressure-locking ball 15 to retract into the storage tank 101. This frees up the flow space, allowing the device to be used without drilling or removing accessories after cementing is completed, without affecting the next operation, thus effectively improving downhole operation efficiency and reducing production costs.

[0054] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art can easily make changes or modifications within the scope of the present invention, and such changes or modifications should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A flip ball seat, comprising: The body (10) has a storage groove (101) formed on its inner wall. The inner sleeve (11) nested at the upper end of the main body (10), and The ball seat (12) is fixed in the inner sleeve (11) by a shear pin (121). A guide rod (14) is provided below the ball seat body (12), and the flip ball seat includes a guide mechanism disposed within the body (10) and adapted to the guide rod (14). The ball is thrown and pressed to cut the shear pin (121). The ball seat (12) and the pressed ball (15) rotate and retract into the storage tank (101) under the traction of the guide rod (14) and the guide mechanism, thereby making room for the flow.

2. The flip ball seat according to claim 1, characterized in that, The guiding mechanism also includes a guide base (21) fixed on the inner wall of the body (10) and a guide groove (22) formed on the guide base (21) in an arc shape.

3. The flip ball seat according to claim 2, characterized in that, The guiding mechanism also includes a first link (23) connected to the guide rod (14), a second link (24) adapted to the guide groove (22), and springs (25) abutting against the first link (23) and the second link (24) respectively. In this configuration, the second link (24) compresses the spring (25) in the initial state and is embedded in the first link (23).

4. The flip ball seat according to claim 3, characterized in that, An anti-swing groove (13) is provided on the inner wall of the body (10). The end hole (221) of the guide groove (22) coincides with the anti-swing groove (13). The second connecting rod (24) is configured to extend through the end hole (221) under the action of the spring (25) to lock with the anti-swing groove (13).

5. The flip ball seat according to claim 4, characterized in that, A buffer pad for bearing pressure on the second connecting rod (24) is provided at the end of the guide groove (22).

6. The flip ball seat according to any one of claims 1 to 5, characterized in that, The guide rod (14) is constructed in a flat shape and is fixed laterally to the lower end face of the ball seat (12).

7. The flip ball seat according to any one of claims 1 to 5, characterized in that, A transition plane (16) is formed on the side of the storage tank (101) near the inner sleeve (11) to guide the ball seat (12) into the tank.

8. The flip ball seat according to any one of claims 2 to 5, characterized in that, The guide chassis (21) is fixed to the inner wall of the body (10) by at least four set screws (26).

9. A downhole construction method utilizing a rotating ball seat according to any one of claims 1 to 8, comprising the following: S1. Throw the ball and pressurize until the critical action pressure is reached so that the setting tool is set in the well; S2. Continue to press until the shear pin (121) is cut off. The ball seat (12) and the pressurized ball (15) rotate and retract into the storage tank (101) under the traction of the guide rod (14) and the guide mechanism, thereby making room for the flow.

10. The downhole construction method according to claim 9, characterized in that, In step S2, the ball seat (12) is rotated 90° counterclockwise.

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