Offshore exploratory well protection mechanism based on barrel-shaped base

Abstract

The invention discloses an offshore exploratory well protection mechanism based on barrel-shaped bases, which comprises four barrel-shaped bases used for penetrating into silt under the water surface; the protection truss is fixedly connected with the barrel-shaped base, and the protection truss is provided with a horn mouth used for installing a marine riser; and the floating box floats on the water surface and is connected with the protection truss through a connecting cable, and a through hole for mounting a marine riser is formed in the floating box. According to the offshore exploratory well protection mechanism based on the barrel-shaped base, the unsupported length of the marine riser can be greatly reduced through the cooperation effect of the horn mouth in the protection truss and the floating box floating on the water surface, and the purpose of protecting the marine riser is achieved.

Description

Technical Field

[0001] This invention relates to the field of offshore oilfield development mechanisms, and more specifically, to an offshore exploration well protection mechanism based on a barrel-shaped base. Background Technology

[0002] When developing offshore oil fields, it is necessary to drill multiple exploratory wells to test the target reservoir. If crude oil is produced from the exploratory wells, it indicates that the target reservoir has further exploitation value. Currently, exploratory wells in offshore oil fields usually need to be sealed. If they are abandoned, it will result in a certain degree of waste of drilling funds. However, if they are not abandoned, it is difficult to achieve independent self-sufficiency of offshore oil field exploratory wells under riser conditions without sealing them.

[0003] In summary, how to achieve independent self-sustaining of risers in offshore oilfield exploration wells without sealing the well is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a marine exploration well protection mechanism based on a barrel-shaped base. This mechanism works in conjunction with the buoy by setting a funnel on the protection truss, thereby extending the unsupported length of the riser to achieve the purpose of protecting the riser and enabling the independent self-sustaining of the riser in offshore oilfield exploration wells without sealing the well.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A marine exploration well protection mechanism based on a barrel-shaped base includes:

[0007] The barrel-shaped base has four sections for penetrating into the mud and sand below the water surface.

[0008] A protective truss is fixedly connected to the barrel-shaped base, and the protective truss is provided with a flared opening for installing a water-proof pipe;

[0009] A pontoon floats on the water surface and is connected to the protective truss by connecting cables. The pontoon is provided with a through hole for installing the water-proof pipe.

[0010] Preferably, the protective truss includes four support columns and a plurality of connecting rods for connecting the support columns, and each of the barrel-shaped bases is provided with one of the support columns, and the flared opening is located in the middle of the four support columns.

[0011] Preferably, the connecting rod includes horizontal connecting rods and cross connecting rods. The horizontal connecting rods include three groups, each group including four rods. The three groups of horizontal connecting rods are respectively located at both ends and the middle of the support column. The cross connecting rods include two groups, each group including four rods. The two groups of cross connecting rods and the three groups of horizontal connecting rods are alternately arranged.

[0012] Preferably, in each group of transverse connecting rods, two adjacent transverse connecting rods are arranged perpendicularly to each other, and the cross connecting rods include two intersecting connecting rods.

[0013] Preferably, the transverse connecting rod is provided with a vertical connecting rod, and the vertical connecting rod is provided in multiple forms and is used to connect the flared mouth.

[0014] Preferably, there are four connecting cables, each of which is connected to a different support column.

[0015] Preferably, the barrel-shaped base is a cylindrical structure, and the ratio of its length to its diameter is between 1:2 and 1:3.

[0016] Preferably, the barrel-shaped base has a hollow structure, and a pressure regulating component is provided inside the barrel-shaped base, which is used to adjust the pressure inside the barrel-shaped base.

[0017] Preferably, the interior of the pontoon is hollow, and the surface of the pontoon is provided with an anti-corrosion coating.

[0018] This invention provides a marine exploration well protection mechanism based on a barrel-shaped base. The barrel-shaped base is equipped with a protective truss, and four barrel-shaped bases are connected by the protective truss. The protective truss has a flared opening, into which the lower end of the riser is directly inserted, providing horizontal support to the lower end of the riser. The upper end of the protective truss is connected to a buoy via a connecting cable. The buoy floats on the water surface, and the riser passes through a through-hole on the buoy, significantly reducing the unsupported length of the riser and thus achieving the purpose of protecting it. This invention has a simple structure, low cost, and enables independent self-storage of the riser in offshore oilfield exploration wells without well sealing. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the offshore well protection mechanism based on a barrel-shaped base provided by the present invention;

[0021] Figure 2 This is a top view of the offshore well protection mechanism based on a barrel-shaped base provided by the present invention.

[0022] Figure label:

[0023] 1-Barrel-shaped base; 2-Floating box; 3-Connecting cable; 4-Protective truss; 401-Support column; 402-Horizontal connecting rod; 403-Cross connecting rod; 404-Vertical connecting rod; 5-Waterproof pipe. Detailed Implementation

[0024] 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.

[0025] The core of this invention is to provide a marine exploration well protection mechanism based on a barrel-shaped base, which can achieve independent self-sustaining of offshore oilfield exploration wells under riser conditions without well sealing.

[0026] It should be noted that the orientation or positional relationship indicated by terms such as "upper", "lower", "front", and "rear" is based on the orientation or positional relationship shown in the accompanying drawings and is only for the purpose of facilitating the description of this application and simplifying the description. It is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0027] This application provides a marine exploration well protection mechanism based on a barrel-shaped base, comprising: a barrel-shaped base 1, a buoy 2, a connecting cable 3, and a protection truss 4;

[0028] Among them, four barrel-shaped bases 1 are provided and used to penetrate into the mud and sand below the water surface;

[0029] The protective truss 4 is fixedly connected to the barrel-shaped base 1, and the protective truss 4 is provided with a flared opening for installing the water-proof pipe 5;

[0030] The pontoon 2 floats on the water surface and is connected to the protective truss 4 by the connecting cable 3. The pontoon 2 is provided with a through hole for installing the water-proof pipe 5.

[0031] Specifically, the barrel-shaped base 1 is fixedly connected to the protective truss 4. The barrel-shaped base 1 and the protective truss 4 are submerged together in the mud and sand below the water surface to achieve positioning. The protective truss 4 has a ring-shaped design with a flared opening that is narrower at the top and wider at the bottom on its inner circumference. The protective truss 4 is connected to the pontoon 2 by a connecting cable 3. The pontoon 2 has a through hole along the vertical direction and can float on the water surface, but it is limited by the connecting cable 3. The length of the connecting cable 3 must keep the pontoon 2 just floating on the water surface without swinging significantly. When the barrel-shaped base 1 and the protective truss 4 are installed in place, the riser 5 passes through the flared opening and the pontoon 2 from bottom to top, so that both the upper and lower ends of the riser 5 can be supported in the horizontal direction, thereby greatly reducing the unsupported length of the riser 5 to achieve the purpose of protecting the riser 5. This allows the riser to be independently self-sustaining in offshore oilfield exploration wells without sealing the well. The overall structure is simple and low-cost, which can save costs.

[0032] Based on the above embodiments, the protective truss 4 includes four support columns 401 and a plurality of connecting rods for connecting the support columns 401. Each barrel-shaped base 1 is provided with a support column 401, and the flared opening is located in the middle of the four support columns 401.

[0033] Specifically, the protective truss 4 includes support columns 401 and connecting rods. The number of support columns 401 is the same as the number of barrel-shaped bases 1. Each barrel-shaped base 1 has an upwardly extending support column 401 on its central axis. Adjacent support columns 401 are connected by connecting rods. The flared opening is set in the middle of the four support columns 401 by a fixing assembly to ensure that the flared opening can fully rely on the barrel-shaped base 1 and support columns 401 to provide horizontal support to the riser pipe 5 when it is impacted by ocean currents in any direction, thus preventing the riser pipe 5 from deforming.

[0034] Based on the above embodiment, the connecting rod includes a transverse connecting rod 402 and a cross connecting rod 403. The transverse connecting rod 402 includes three sets, each set including four rods. The three sets of transverse connecting rods 402 are respectively located at both ends and the middle of the support column 401. The cross connecting rod 403 includes two sets, each set including four rods. The two sets of cross connecting rods 403 and the three sets of transverse connecting rods 402 are alternately arranged.

[0035] Specifically, both the transverse connecting rod 402 and the cross connecting rod 403 need to be made of high-strength materials. The connection method between the transverse connecting rod 402 and the support column 401 and the connection method between the cross connecting rod 403 and the support column 401 are preferably welded. The three sets of transverse connecting rods 402 are respectively set at the upper, middle and lower parts of the support column 401 to ensure reliable connection between the support columns 401. In addition, the setting of the cross connecting rod 403 can also improve the overall structural strength and prevent structural deformation caused by seawater flow.

[0036] Based on the above embodiments, in each group of transverse connecting rods 402, two adjacent transverse connecting rods 402 are arranged perpendicularly to each other, and the cross connecting rods 403 include two cross connecting rods.

[0037] Specifically, each set of transverse connecting rods 402 is set in the same horizontal plane. Each set of transverse connecting rods 402 includes four rods, and the four transverse connecting rods 402 are completely identical. The two adjacent transverse connecting rods 402 are perpendicular to each other, so that the support column 401 and the barrel base 1 are arranged in a square. This ensures that the horizontal support force provided by the protective truss 4 to the flared mouth in all directions is the same. No matter how the seawater flows, the protective truss 4 can provide stable horizontal support to the flared mouth and the water-proof pipe 5, preventing their deformation.

[0038] Based on the above embodiment, the transverse connecting rod 402 is provided with a vertical connecting rod 404, and the vertical connecting rod 404 is provided with multiple rods and is used to connect the flared mouth.

[0039] Specifically, each transverse connecting rod 402 is provided with a vertical connecting rod 404 that is perpendicular to the transverse connecting rod 402, and the vertical connecting rod 404 and the transverse connecting rod are in the same plane. The flared mouth is fixed by the vertical connecting rod 404 to ensure the structural stability of the flared mouth.

[0040] In some embodiments, four connecting cables 3 are provided, each connecting cable 3 being connected to a different support column 401.

[0041] Specifically, the connecting cable 3 is connected to the support column 401 and the pontoon 2. The length of the connecting cable 3 is determined according to the distance between the top of the support column 401 and the water surface to ensure that the pontoon 2 can float directly above the flared end, thereby providing horizontal support for the riser 5 at the water surface. The connecting cable 3 is made of materials such as ultra-high molecular weight polyethylene to ensure that the cable has high corrosion resistance and effectively reduces the unsupported length of the riser 5, thereby enabling the independent survival of the offshore exploration well and providing support for the resumption of exploration well production in offshore oil fields.

[0042] In some embodiments, the barrel-shaped base 1 is a cylindrical structure, and the ratio of its length to its diameter is between 1:2 and 1:3.

[0043] Specifically, the barrel base 1 adopts a conventional cylindrical barrel base with a length-to-diameter ratio of 1:2 to 1:3, thereby providing better pull-out resistance and anti-slip force.

[0044] In some embodiments, the barrel-shaped base 1 is a hollow structure, and a pressure regulating component is provided inside the barrel-shaped base 1. The pressure regulating component is used to adjust the pressure inside the barrel-shaped base 1.

[0045] Specifically, the barrel-shaped base 1 adopts a 4-barrel arrangement. When the barrel-shaped base 1 is penetrated under negative pressure, the pressure inside the barrel is adjusted by the pressure regulating component to create a pressure difference between the barrel bases, thereby achieving the leveling problem during the penetration process.

[0046] Optionally, the pressure regulating component can be a pressure regulator that can automatically adjust the pressure to maintain a stable system pressure.

[0047] Based on the above embodiments, the interior of the float box 2 is a hollow structure, and the surface of the float box 2 is provided with an anti-corrosion coating.

[0048] Specifically, the float 2 is a cylindrical structure with a through hole, made of conventional high-strength steel, and coated with anti-corrosion paint. Its internal cavity has sufficient space to reduce the density of the float 2 and ensure that the float 2 can float on the water surface, so as to minimize the unsupported length of the riser pipe 5.

[0049] The installation and usage methods for the aforementioned offshore well protection mechanism based on a barrel-shaped base are as follows:

[0050] The offshore well protection mechanism based on a barrel-shaped base is transported to the target well location by a construction vessel. A floating crane then hoists the entire mechanism above the riser 5. Once in place, the mechanism is slowly lowered. The riser 5 passes through the funnel-shaped opening and pontoon 2 within the horizontal layer of the protective truss 4. After the barrel-shaped base 1 naturally sinks to a certain depth under gravity, a negative pressure extraction operation is initiated, allowing the barrel-shaped base 1 to penetrate under negative pressure. Once the top of the barrel-shaped base 1 reaches the mud surface, the negative pressure extraction operation is stopped, and the offshore well protection mechanism is in place. The pontoon 2 floats on the water surface, and the tension provided by the connecting cable 3 holds the riser 5, thus providing protective support for it.

[0051] When the offshore well protection mechanism needs to be withdrawn, it is only necessary to inflate the barrel-shaped base 1 to make the internal pressure of the barrel-shaped base 1 higher than the external pressure, thereby lifting the offshore well protection mechanism, and the barrel-shaped base 1 is removed from the mud surface. Then, the offshore well protection mechanism is lifted by the floating crane and transported to the next target well, thus realizing the reuse of the offshore well protection mechanism.

[0052] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0053] The above provides a detailed description of a marine exploration well protection mechanism based on a barrel-shaped base provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A marine exploration well protection mechanism based on a barrel-shaped base, characterized in that, include: The barrel-shaped base (1) has four parts and is used to penetrate into the mud and sand below the water surface; The protective truss (4) is fixedly connected to the barrel-shaped base (1), and the protective truss (4) is provided with a flared opening for installing the water-proof pipe (5); The pontoon (2) floats on the water surface and is connected to the protective truss (4) by the connecting cable (3). The pontoon (2) is provided with a through hole for installing the water-proof pipe (5).

2. The offshore well protection mechanism based on a barrel-shaped base according to claim 1, characterized in that, The protective truss (4) includes four support columns (401) and multiple connecting rods for connecting the support columns (401). Each barrel-shaped base (1) is provided with a support column (401), and the flared opening is located in the middle of the four support columns (401).

3. The offshore well protection mechanism based on a barrel-shaped base according to claim 2, characterized in that, The connecting rod includes a transverse connecting rod (402) and a cross connecting rod (403). The transverse connecting rod (402) includes three groups, each group including four rods. The three groups of transverse connecting rods (402) are respectively located at both ends and the middle of the support column (401). The cross connecting rod (403) includes two groups, each group including four rods. The two groups of cross connecting rods (403) and the three groups of transverse connecting rods (402) are alternately arranged.

4. The offshore well protection mechanism based on a barrel-shaped base according to claim 3, characterized in that, In each group of transverse connecting rods (402), two adjacent transverse connecting rods (402) are arranged perpendicularly to each other, and the cross connecting rod (403) includes two cross connecting rods.

5. The offshore well protection mechanism based on a barrel-shaped base according to claim 4, characterized in that, The horizontal connecting rod (402) is provided with a vertical connecting rod (404), and the vertical connecting rod (404) is provided in multiple forms and is used to connect the horn mouth.

6. The offshore well protection mechanism based on a barrel-shaped base according to claim 4, characterized in that, There are four connecting cables (3), each of which is connected to a different support column (401).

7. The offshore well protection mechanism based on a barrel-shaped base according to claim 1, characterized in that, The barrel-shaped base (1) is a cylindrical structure, and the ratio of its length to its diameter is between 1:2 and 1:

3.

8. The offshore well protection mechanism based on a barrel-shaped base according to claim 1, characterized in that, The barrel-shaped base (1) is a hollow structure, and a pressure regulating component is provided inside the barrel-shaped base (1). The pressure regulating component is used to adjust the pressure inside the barrel-shaped base (1).

9. The offshore well protection mechanism based on a barrel-shaped base according to any one of claims 1 to 8, characterized in that, The interior of the pontoon (2) is hollow, and the surface of the pontoon (2) is coated with an anti-corrosion coating.

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