Offshore exploratory well protection mechanism based on barrel-shaped base

Abstract

The utility model discloses an offshore exploratory well protection mechanism based on barrel-shaped bases, which comprises the following components: four barrel-shaped bases which are 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] The utility model relates to the technical field of offshore oilfield exploitation mechanisms, and more specifically, to an offshore exploration well protection mechanism based on a barrel-shaped base. Background Art

[0002] After decades of development, China's offshore oilfields are gradually entering the late stage of development. As the development difficulty increases, the development cost gradually rises, and the economic efficiency of oilfield development becomes increasingly important. At the same time, China is currently vigorously developing marginal oilfields, which are more sensitive to the economic efficiency of development. Therefore, it can be seen that how to reduce the comprehensive cost of oilfield development has become a key factor affecting the development of China's offshore oilfields.

[0003] When developing offshore oilfields, it is first necessary to drill multiple exploration wells to test the production of the target oil reservoir. If crude oil is produced from the exploration wells, it indicates that the target oil reservoir has further exploitation value. Currently, the exploration wells in offshore oilfields usually need to be sealed. If abandoned, it will cause a certain degree of waste of drilling funds. If not abandoned, it is difficult to achieve independent self-existence under the condition of riser pipes without sealing the exploration wells in offshore oilfields.

[0004] In summary, how to achieve the independent self-existence of riser pipes under the condition of not sealing the exploration wells in offshore oilfields is an urgent problem to be solved by those skilled in the art at present. Content of the Utility Model

[0005] In view of this, the purpose of the utility model is to provide an offshore exploration well protection mechanism based on a barrel-shaped base. The mechanism cooperates with the flaring mouth arranged on the protection truss and the floating box, so as to be able to reduce the unsupported length of the riser pipe, so as to achieve the purpose of protecting the riser pipe and realize the independent self-existence of the riser pipe under the condition of not sealing the exploration wells in offshore oilfields.

[0006] In order to achieve the above purpose, the utility model provides the following technical scheme:

[0007] An offshore exploration well protection mechanism based on a barrel-shaped base, comprising:

[0008] Four barrel-shaped bases for penetrating into the sediment under the water surface;

[0009] A protection truss fixedly connected to the barrel-shaped base, and a flaring mouth for installing a riser pipe is arranged on the protection truss;

[0010] A floating box floating on the water surface and connected to the protection truss through a connecting cable, and a through hole for installing the riser pipe is arranged on the floating box.

[0011] Preferably, the protective truss includes four support columns and a plurality of connecting rods for connecting the support columns. One support column is provided on each of the barrel-shaped bases, and the bell mouth is arranged in the exact middle of the four support columns.

[0012] Preferably, the connecting rods include horizontal connecting rods and cross connecting rods. There are three groups of horizontal connecting rods, with four in each group. The three groups of horizontal connecting rods are respectively arranged at both ends and the middle position of the support columns. There are two groups of cross connecting rods, with four in each group. The two groups of cross connecting rods and the three groups of horizontal connecting rods are arranged alternately.

[0013] Preferably, two adjacent horizontal connecting rods in each group of horizontal connecting rods are arranged perpendicular to each other, and the cross connecting rod includes two intersecting connecting rods.

[0014] Preferably, vertical connecting rods are provided on the horizontal connecting rods. There are a plurality of vertical connecting rods and they are used to connect the bell mouth.

[0015] Preferably, there are four connecting cables, and each connecting cable is connected to a different support column.

[0016] Preferably, the barrel-shaped base is a cylindrical structure, and the ratio of its length to diameter ranges from 1:2 to 1:3.

[0017] Preferably, the barrel-shaped base is a hollow structure, and a pressure regulating component is arranged inside the barrel-shaped base. The pressure regulating component is used to adjust the pressure inside the barrel-shaped base.

[0018] Preferably, the inside of the floating box is a hollow structure, and an anti-corrosion coating is provided on the surface of the floating box.

[0019] A kind of offshore well exploration protection mechanism based on a barrel-shaped base provided by the present utility model. A protective truss is arranged on the barrel-shaped base of the mechanism. The four barrel-shaped bases are connected through the protective truss. A bell mouth is arranged on the protective truss. The lower end of the riser is directly inserted into the bell mouth, which can provide horizontal support for the lower end part of the riser. The upper end of the protective truss is connected to the floating box through a connecting cable. The floating box floats on the water surface. The riser passes through the through hole on the floating box, so that the unsupported length of the riser can be greatly reduced, so as to achieve the purpose of protecting the riser. The structure of the present application is simple and the cost is low, and it can realize the independent self-existence of the riser under the condition of not sealing the well in the offshore oilfield well exploration. Description of the Drawings

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0021] Figure 1 Structural schematic diagram of the offshore well exploration protection mechanism based on a barrel-shaped base provided by the present invention;

[0022] Figure 2 Top view of the offshore well exploration protection mechanism based on a barrel-shaped base provided by the present invention.

[0023] Reference numerals:

[0024] 1 - Barrel-shaped base; 2 - Float box; 3 - Connecting cable; 4 - Protection truss; 401 - Support column; 402 - Horizontal connecting rod; 403 - Cross connecting rod; 404 - Vertical connecting rod; 5 - Riser. Detailed implementation manners

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0026] The core of the present invention is to provide an offshore well exploration protection mechanism based on a barrel-shaped base, which can achieve independent self-existence under the condition of the riser without shutting in the well in an offshore oilfield.

[0027] It should be noted that the orientation or positional relationship indicated by "up", "down", "front", "rear", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0028] An offshore well exploration protection mechanism based on a barrel-shaped base provided by the present application includes: a barrel-shaped base 1, a float box 2, a connecting cable 3 and a protection truss 4;

[0029] Among them, there are four barrel-shaped bases 1 and they are used to penetrate into the sediment under the water surface;

[0030] The protective truss 4 is fixedly connected to the barrel-shaped base 1, and a bell mouth for installing the riser 5 is provided on the protective truss 4.

[0031] The floating box 2 floats on the water surface and is connected to the protective truss 4 through a connecting cable 3. A through hole for installing the riser 5 is provided on the floating box 2.

[0032] Specifically, the barrel-shaped base 1 is fixedly connected to the protective truss 4. Sinking the barrel-shaped base 1 and the protective truss 4 together into the sediment under the water surface can achieve positioning. The protective truss 4 is designed in a ring shape, and a bell mouth with a narrow upper part and a wide lower part is arranged on its inner circumference. The protective truss 4 is connected to the floating box 2 through a connecting cable 3. A through hole is arranged vertically on the floating box 2 and it can float on the water surface, but it is restricted by the connecting cable 3. The length of the connecting cable 3 needs to be such that the floating box 2 just floats on the water surface without large swings. When the barrel-shaped base 1 and the protective truss 4 are installed in place, the riser 5 passes through the bell mouth and the floating box 2 from bottom to top in sequence, 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, so that the riser can be independently self-existent under the condition of not sealing the well in the offshore oilfield exploration well. The overall structure is simple and the cost is low, which can save costs.

[0033] On the basis of the above embodiment, the protective truss 4 includes four support columns 401 and a plurality of connecting rods for connecting the support columns 401. One support column 401 is provided on each barrel-shaped base 1, and the bell mouth is arranged in the exact middle of the four support columns 401.

[0034] 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. An upward-extending support column 401 is arranged on the central axis of each barrel-shaped base 1. The adjacent support columns 401 are connected by connecting rods. The bell mouth is arranged in the exact middle of the four support columns 401 through a fixing component to ensure that the bell mouth can fully rely on the barrel-shaped base 1 and the support columns 401 to provide horizontal support to the riser 5 when being impacted by ocean currents in any direction, preventing the deformation of the riser 5.

[0035] On the basis of the above embodiment, the connecting rods include transverse connecting rods 402 and cross connecting rods 403. There are three groups of transverse connecting rods 402, and each group includes four. The three groups of transverse connecting rods 402 are respectively arranged at both ends and the middle position of the support columns 401. There are two groups of cross connecting rods 403, and each group includes four. The two groups of cross connecting rods 403 and the three groups of transverse connecting rods 402 are arranged alternately.

[0036] Specifically, both the horizontal connecting rod 402 and the cross connecting rod 403 need to be made of high-strength materials, and the connection methods of the horizontal connecting rod 402 with the support column 401 and the cross connecting rod 403 with the support column 401 are preferably welding. The three groups of horizontal connecting rods 402 are respectively arranged at the upper, middle and lower parts of the support column 401 to ensure the 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.

[0037] On the basis of the above embodiments, two adjacent horizontal connecting rods 402 in each group of horizontal connecting rods 402 are arranged perpendicular to each other, and the cross connecting rod 403 includes two intersecting connecting rods.

[0038] Specifically, each group of horizontal connecting rods 402 is arranged in the same horizontal plane. Each group of horizontal connecting rods 402 includes four, and the four horizontal connecting rods 402 are exactly the same. Two adjacent horizontal connecting rods 402 among the four horizontal connecting rods 402 are perpendicular to each other, so that the support columns 401 and the barrel-shaped base 1 are both arranged in a square layout, so that the horizontal support forces provided by the protection truss 4 in all directions of the flare are the same, and no matter how the seawater flows, it can ensure that the protection truss 4 provides stable horizontal support for the flare and the riser 5 to prevent its deformation.

[0039] On the basis of the above embodiments, vertical connecting rods 404 are provided on the horizontal connecting rod 402, and a plurality of vertical connecting rods 404 are provided and used to connect the flare.

[0040] Specifically, a vertical connecting rod 404 perpendicular to the horizontal connecting rod 402 is arranged on each horizontal connecting rod 402, and the vertical connecting rod 404 and the horizontal connecting rod are in the same plane. The flare is fixed through the vertical connecting rod 404 to ensure the structural stability of the flare.

[0041] In some embodiments, there are four connecting cables 3, and each connecting cable 3 is connected to a different support column 401.

[0042] Specifically, the connecting cable 3 is connected to the support column 401 and the floating box 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, so as to ensure that the floating box 2 can float directly above the flare, thereby providing a horizontal support force 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 realizing the independent self-existence of the offshore well and providing support for the restoration of production of the offshore oilfield well.

[0043] In some embodiments, the barrel-shaped base 1 is a cylindrical structure, and the ratio of its length to diameter ranges from 1:2 to 1:3.

[0044] Specifically, the barrel-shaped base 1 adopts a conventional cylindrical bucket foundation with a length-diameter ratio of 1:2 to 1:3, thereby providing better uplift resistance and anti-slip force.

[0045] In some embodiments, the barrel-shaped base 1 is a hollow structure, and a pressure regulating component is arranged inside the barrel-shaped base 1 for adjusting the pressure inside the barrel-shaped base 1.

[0046] Specifically, the barrel-shaped base 1 adopts a four-barrel layout scheme. When the barrel-shaped base 1 is negatively penetrated, the pressure inside the barrel is adjusted through the pressure regulating component to create a pressure difference between the barrel foundations, thereby realizing the leveling problem during the sinking and penetration process.

[0047] Optionally, the pressure regulating component can be a pressure regulator, which can automatically adjust the pressure to maintain the stability of the system pressure.

[0048] Based on the above embodiments, the interior of the floating box 2 is a hollow structure, and an anti-corrosion coating is provided on the surface of the floating box 2.

[0049] Specifically, the floating box 2 is a cylindrical structure with a through hole, made of conventional high-strength steel, coated with anti-corrosion paint on the outer layer, and has sufficient space in its internal cavity to reduce the density of the floating box 2, ensuring that the floating box 2 can float on the water surface to minimize the unsupported length of the riser 5.

[0050] For the above-mentioned offshore well protection mechanism based on the barrel-shaped base, its installation method and usage method are as follows:

[0051] The offshore well protection mechanism based on the barrel-shaped base is transported to the target well location by a construction ship. Through a floating crane device, the offshore well protection mechanism is hoisted as a whole above the riser 5. After being in place, the offshore well protection mechanism is slowly lowered. The riser 5 passes through the bell mouth and the floating box 2 in the horizontal layer of the protection truss 4. When the barrel-shaped base 1 naturally penetrates to a certain depth by gravity, the negative pressure pumping operation is started on the barrel-shaped base 1 to make the barrel-shaped base 1 negatively penetrate. When the top of the barrel-shaped base 1 reaches the mud surface, the negative pressure pumping operation is stopped, and the offshore well protection mechanism is in place. The floating box 2 floats on the water surface by buoyancy, and the tension provided by the connecting cable 3 can hold the riser 5, thus completing the protection and support of the riser 5.

[0052] When the offshore well protection mechanism needs to be evacuated, only the inflation operation needs to be carried out on the barrel-shaped base 1 to make the pressure inside the barrel-shaped base 1 higher than the external pressure, thereby jacking up the offshore well protection mechanism, separating the barrel-shaped base 1 from the mud surface, and then lifting the offshore well protection mechanism by a floating crane device and transporting it to the next target well, thus realizing the reuse of the offshore well protection mechanism.

[0053] In the present specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other.

[0054] The above has introduced in detail a marine exploration well protection mechanism based on a barrel-shaped base provided by the present utility model. Specific examples are used herein to elaborate on the principle and implementation manner of the present utility model. The description of the above embodiments is only used to help understand the method and its core idea of the present utility model. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present utility model, several improvements and modifications can be made to the present utility model, and these improvements and modifications also fall within the protection scope of the claims of the present utility model.

Claims

1. An offshore well protection mechanism based on a barrel-shaped base, characterized in that: include: A barrel-shaped base (1), provided with four barrel-shaped bases (1), used for penetrating into the mud and sand under the water surface; A protection truss (4) is fixedly connected to the barrel-shaped base (1), and a bell mouth for installing a watertight pipe (5) is provided on the protection truss (4); The buoy (2) floats on the water surface and is connected to the protection truss (4) via a connecting cable (3). The buoy (2) is provided with a through hole for installing the watertight pipe (5).

2. The offshore well protection mechanism based on a barrel-shaped base according to claim 1 is characterized in that: The protection truss (4) comprises four support columns (401) and a plurality of connecting rods for connecting the support columns (401); each of the barrel-shaped bases (1) is provided with one support column (401); and the bell mouth is arranged 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 is characterized in that: The connecting rods include transverse connecting rods (402) and cross connecting rods (403). The transverse connecting rods (402) include three groups, each group includes four rods, and the three groups of transverse connecting rods (402) are respectively arranged at both ends and a middle position of the support column (401). The cross connecting rods (403) include two groups, each group includes four rods, and 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 is characterized in that: Two adjacent transverse connecting rods (402) in each group of transverse connecting rods (402) are arranged perpendicular to each other, and the cross connecting rod (403) comprises two cross connecting rods.

5. The offshore well protection mechanism based on a barrel-shaped base according to claim 4 is characterized in that: A vertical connecting rod (404) is provided on the transverse connecting rod (402), and a plurality of the vertical connecting rods (404) are provided and are used to connect the bell mouth.

6. The offshore well protection mechanism based on a barrel-shaped base according to claim 4 is characterized in that: Four connecting cables (3) are provided, and each connecting cable (3) is connected to a different supporting column (401).

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

3.

8. The offshore well protection mechanism based on a barrel-shaped base according to claim 1 is characterized in that: The barrel-shaped base (1) is a hollow structure, and a pressure regulating component is arranged inside the barrel-shaped base (1), and 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 buoyancy box (2) is a hollow structure, and the surface of the buoyancy box (2) is provided with an anti-corrosion coating.

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