Offshore installation method of heavy jacket

Abstract

The invention discloses an offshore installation method for a heavy jacket. The offshore installation method comprises the following steps that S1, the seabed state of a jacket installation area is detected through equipment; s2, the semi-submersible transport ship carries the heavy jacket to the wind field construction sea area; s3, the heavy crane ship enters the wind field construction sea area, and the heavy crane ship and the semi-submersible transport ship are arranged in a T shape; s4, a rigging on the heavy crane ship is hung on a lifting lug of the heavy jacket; s5, sea binding pieces of the heavy jacket are unbound, and the semi-submersible transport ship is prepared and checked before diving; s6, the semi-submersible transport ship begins to submerge, and the rigging on the heavy crane ship begins to load; and S7, after the heavy jacket is completely separated from the semi-submersible transport ship, the heavy crane ship hoists the heavy jacket to a mounting position. According to the invention, the offshore installation of the heavy jacket is realized by combining the hoisting of the crane ship and the floating of the semi-submersible transport ship.

Description

Technical Field

[0001] The present invention relates to the installation technology of offshore wind power jacket, and more specifically, to an offshore installation method for a heavy jacket. Background Art

[0002] When installing the jacket in an offshore wind power project, a crane ship is generally used for hoisting during offshore construction, and the process is as follows:

[0003] The crane ship and the jacket transport ship are positioned at the installation site → the crane ship hooks up → the jacket is unfastened → the crane ship's boom slowly lifts → the jacket detaches from the transport ship → the crane ship and the jacket are moved to the installation position → the jacket completes offshore installation → the slings are disassembled → the crane ship and the jacket transport ship return, so as to complete the offshore installation operation.

[0004] However, for a heavy jacket (the weight of the jacket is greater than 10,000 tons), due to the ultra-large weight and external dimensions of the jacket, the existing crane ships can no longer achieve installation through the above-mentioned offshore hoisting. Summary of the Invention

[0005] Aiming at the defects existing in the prior art, the purpose of the present invention is to provide an offshore installation method for a heavy jacket, which realizes the offshore installation of the heavy jacket by combining the hoisting of a crane ship and the floating of a semi-submersible transport ship.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] An offshore installation method for a heavy jacket, comprising the following steps:

[0008] S1, detecting the seabed state of the installation area of the jacket through equipment;

[0009] S2, the semi-submersible transport ship transports the heavy jacket to the construction sea area of the wind farm;

[0010] S3, the heavy crane ship enters the construction sea area of the wind farm and is arranged in a T shape with the semi-submersible transport ship;

[0011] S4, hanging the slings on the heavy crane ship onto the lifting lugs of the heavy jacket;

[0012] S5, unfastening the sea fasteners of the heavy jacket, and the semi-submersible transport ship makes preparations and inspections before diving;

[0013] S6, the semi-submersible transport ship starts to dive, and the slings on the heavy crane ship start to be loaded;

[0014] S7, after the heavy jacket is completely detached from the semi-submersible transport ship, the heavy crane ship hoists the heavy jacket to the installation position.

[0015] Preferably, in step S1, before installing the heavy jacket, the seabed conditions within a range of 200 meters × 200 meters of the installation area of the heavy jacket are detected in advance using equipment to check whether there are obvious convex obstacles or other abnormal features in the installation area. If so, they need to be processed in advance.

[0016] Preferably, in step S2, the semi-submersible transport ship is assisted by an anchor boat and four fixed anchors are dropped for fixation.

[0017] Preferably, in step S3, the heavy lift vessel uses DP positioning or anchors are dropped by the anchor boat for positioning.

[0018] Preferably, in step S4, the preparations and inspections before the semi-submersible transport ship dives specifically include whether the sea fasteners are cut, whether the deck equipment of the semi-submersible ship is cleaned, and whether the ballast pump set is in good condition.

[0019] Preferably, step S6 specifically includes:

[0020] The rigging on the heavy lift vessel starts to be loaded according to the design requirements. After the console shows that the rigging load on the heavy lift vessel reaches the theoretical value for the heavy jacket to break away from the semi-submersible transport ship, then check whether the actual distance between the heavy jacket and the semi-submersible transport ship reaches the theoretical value. After reaching it, the heavy lift vessel is ready to shift.

[0021] Preferably, in step S7, the heavy lift vessel slowly moves through DP or slowly moves the heavy lift vessel to the installation position of the heavy jacket through the anchor winch.

[0022] The offshore installation method of a heavy jacket provided by the present invention has the following specific beneficial effects:

[0023] 1) High installation efficiency: Most of the assembly work of the jacket can be completed on shore, reducing the time and workload of offshore operations. At the same time, the floating transportation process of the semi-submersible transport ship is relatively stable, which can effectively shorten the installation cycle and improve the overall project progress;

[0024] 2) Less affected by sea conditions: The semi-submersible transport ship can also operate in medium sea conditions, has strong adaptability to wind waves and ocean currents, and has a relatively long operation window period, which can reduce the impact of poor sea conditions on the installation operation and improve the safety and reliability of construction;

[0025] 3) High positioning accuracy: The heavy jacket is lifted from the semi-submersible transport ship by a heavy lift vessel and accurately installed at the predetermined position. Through the precise operation of the heavy lift vessel, the installation deviation of the heavy jacket can be controlled within a small range, ensuring the accurate docking of the heavy jacket with the seabed foundation and meeting the strict requirements for the structural installation accuracy in offshore oil and gas development.

[0026] 4) Strong adaptability: It is applicable to various water depths and seabed conditions. Whether in shallow or deep sea areas, as long as the lifting capacity and working radius of the heavy lift vessel meet the requirements, the lifting and installation of the heavy jacket can be carried out, showing good adaptability to different marine environments.

[0027] 5) Fast construction speed: The overall installation of the heavy jacket can be completed in one lifting. Compared with some other methods that require step-by-step installation, it can greatly shorten the offshore operation time, reduce the input of manpower and material resources in offshore construction, improve construction efficiency, and reduce construction costs. Description of the Drawings

[0028] Figure 1 is a schematic layout diagram of the heavy lift vessel and the semi-submersible transport ship in the offshore installation method of the present invention;

[0029] Figure 2 is Figure 1 a top view schematic diagram of Detailed Embodiment

[0030] In order to better understand the above technical solutions of the present invention, the technical solutions of the present invention will be further described below with reference to the drawings and embodiments.

[0031] Combined with Figure 1 and Figure 2 shown, an offshore installation method for a heavy jacket provided by the present invention includes the following steps:

[0032] S1, Detect the seabed state of the jacket installation area through equipment;

[0033] S2, After the semi-submersible transport ship 2 transports the heavy jacket 1 to the wind farm construction sea area, drop the eight-character anchors to fix the semi-submersible transport ship 2;

[0034] S3, The heavy lift vessel 3 enters the wind farm construction sea area and is arranged in a T shape with the semi-submersible transport ship 2;

[0035] S4, Unbind the main hook on the heavy lift vessel 3 and hang the rigging on the lifting lugs of the heavy jacket 1;

[0036] S5, Unbind the sea fasteners of the heavy jacket 1, and the semi-submersible transport ship 2 makes preparations and inspections before diving;

[0037] S6. The semi-submersible transport ship 2 starts to submerge, and the rigging on the heavy lift vessel 3 begins to be gradually loaded.

[0038] S7. After the heavy jacket 1 is completely detached from the semi-submersible transport ship 2, the heavy lift vessel 3 hoists the heavy jacket 1 to the installation position. After the heavy jacket 1 is fine-tuned to meet the design requirements, it is installed in place.

[0039] In the above step S1, before installing the heavy jacket 1, the seabed conditions within a range of 200 meters × 200 meters of the installation area of the heavy jacket 1 are detected in advance using equipment to check whether there are obvious convex obstacles or other abnormal features in this installation area. If so, treatment needs to be carried out in advance.

[0040] In the above step S2, the semi-submersible transport ship 2 is assisted by an anchor boat and four fixed anchors are cast according to the design requirements for fixation.

[0041] In the above step S3, the heavy lift vessel 3 uses DP positioning or anchors are cast by an anchor boat for positioning.

[0042] In the above step S4, the preparations and inspections before the semi-submersible transport ship 2 submerges specifically include whether the sea fasteners are cut, whether the deck equipment of the semi-submersible ship is cleaned, and whether the ballast pump set is in good condition.

[0043] The above step S6 specifically includes:

[0044] The rigging on the heavy lift vessel 3 starts to be loaded according to the design requirements. After the console shows that the load of the rigging on the heavy lift vessel 3 reaches the theoretical value for the heavy jacket 1 to be detached from the semi-submersible transport ship 2, then check whether the actual distance between the heavy jacket 1 and the semi-submersible transport ship 2 reaches the theoretical value. After reaching, the heavy lift vessel 3 prepares to shift.

[0045] In the above step S7, the heavy lift vessel 3 slowly moves through DP or slowly moves the heavy lift vessel 3 to the installation position of the heavy jacket 1 through the anchor winch.

[0046] In summary, the present invention realizes the offshore installation of the heavy jacket by combining the hoisting of a heavy lift vessel and the floating support of a semi-submersible transport ship (that is, the combination of two methods: hoisting + floating).

[0047] Those of ordinary skill in the art in this technical field should recognize that the above embodiments are only used to illustrate the present invention and are not used to limit the present invention. As long as it is within the scope of the essential spirit of the present invention, changes and modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. An offshore installation method for a heavy jacket, characterized in that, It includes the following steps: S1. Detect the seabed condition of the installation area of the jacket through equipment; S2. The semi-submersible transport ship transports the heavy jacket to the construction sea area of the wind farm; S3. The heavy lift vessel enters the construction sea area of the wind farm and is arranged in a T shape with the semi-submersible transport ship; S4. Hang the rigging on the heavy lift vessel onto the lifting lugs of the heavy jacket; S5. Unbind the sea fasteners of the heavy jacket, and the semi-submersible transport ship makes preparations and inspections before diving; S6. The semi-submersible transport ship starts to dive, and the rigging on the heavy lift vessel starts to be loaded; S7. After the heavy jacket is completely detached from the semi-submersible transport ship, the heavy lift vessel hoists the heavy jacket to the installation position.

2. The offshore installation method of the heavy jacket according to claim 1, characterized in that, In step S1, before installing the heavy jacket, use equipment to detect the seabed conditions within a range of 200 meters × 200 meters of the installation area of the heavy jacket in advance, and check whether there are obvious raised obstacles or other abnormal features in this installation area. If so, they need to be processed in advance.

3. The offshore installation method of the heavy jacket according to claim 1, characterized in that: In step S2, the semi-submersible transport ship is assisted by an anchor boat and four fixed anchors are dropped for fixation.

4. The offshore installation method of the heavy jacket according to claim 1, characterized in that: In step S3, the heavy lift vessel uses DP positioning or anchors are dropped by an anchor boat for positioning.

5. The offshore installation method of the heavy jacket according to claim 1, characterized in that: In step S4, the preparations and inspections made by the semi-submersible transport ship before diving specifically include whether the sea fasteners are cut off, whether the deck equipment of the semi-submersible ship is cleaned up, and whether the ballast pump set is in good condition.

6. The offshore installation method of the heavy jacket according to claim 1, characterized in that, Step S6 specifically includes: The rigging on the heavy lift vessel starts to be loaded according to the design requirements. After the console shows that the lifting load of the rigging on the heavy lift vessel reaches the theoretical value for the heavy jacket to be detached from the semi-submersible transport ship, then check whether the actual distance between the heavy jacket and the semi-submersible transport ship is up to the theoretical value. After reaching it, the heavy lift vessel is ready to shift.

7. The offshore installation method of the heavy jacket according to claim 1, characterized in that: In step S7, the heavy lift vessel slowly moves through DP or slowly moves the heavy lift vessel to the installation position of the heavy jacket through the anchor winch.

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