Multi-functional ship

Abstract

To provide a multi-functional ship which balances cost and mobility when the construction and the maintenance of a floating-type, offshore wind power generation facility are performed.SOLUTION: A multi-functional ship is switchable between a survey mode in which a derrick is installed on the deck; an anchor-handling mode in which an anchor of an offshore wind power generation facility can be mounted on the deck, a chain can be accommodated in a storage space below the deck, and the anchor can be installed on the seabed with the chain paid out; and a maintenance mode in which a gangway is installed on the deck.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a multi-function vessel. [Background technology]

[0002] When constructing a floating offshore wind power generation facility such as that shown in Patent Document 1, a survey process, an anchor handling process, and a construction process are typically carried out. In the survey process, a geological survey of the seabed at the site where the floating offshore wind power generation facility will be installed is carried out. In the anchor handling process, chains, anchors, etc. used in the construction of the floating offshore wind power generation facility are transported to the construction site, and the chains are extended and the anchors are installed on the seabed. In the construction process, suction piles are dropped into the water, and the offshore wind power generation facility is secured using the suction piles, anchors, etc.

[0003] After the floating offshore wind power generation facility is constructed, a process of maintaining and inspecting the facility (simply referred to as the maintenance process in this specification) is carried out. During the maintenance process, workers use a gangway installed on the ship to transfer to the floating offshore wind power generation facility and perform their work. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-163979 Summary of the Invention [Problem to be solved by the invention]

[0005] To carry out the survey, anchor handling, construction, and maintenance processes, vessels with the appropriate functions for each process are required. For example, the survey process requires a vessel equipped with a scaffolding, while the anchor handling process requires a vessel with space to carry chains, anchors, etc. Furthermore, the construction process requires a vessel equipped with a large construction crane that can drop suction piles into the water, and the maintenance process requires a vessel equipped with a gangway.

[0006] However, if multiple dedicated ships with each of the above functions were prepared, the costs of acquiring and maintaining each dedicated ship would increase. Furthermore, during periods when a dedicated ship is not performing its designated process, that dedicated ship would be idle, reducing its utilization rate. As a result, there is the issue of difficulty in recovering operating costs. Furthermore, if a single ship were to simultaneously accommodate a rafter, chain storage space, a large construction crane, and a gangway, the ship's hull would be excessively large, impairing its maneuverability.

[0007] The present invention has been made in consideration of the above circumstances, and aims to provide a multi-functional vessel that achieves both cost and maneuverability when constructing and maintaining floating offshore wind power generation facilities. [Means for solving the problem]

[0008] In order to solve the above problems, the multifunctional vessel according to aspect 1 of the present invention is switchable between an investigation mode in which a scaffold is attached to the deck, an anchor handling mode in which the anchor of an offshore wind power generation facility can be placed on the deck, the chain of the offshore wind power generation facility can be stored in the storage space below the deck, and the anchor can be installed on the seabed and the chain can be extended, and a maintenance mode in which a gangway is attached to the deck.

[0009] A second aspect of the present invention is a multi-function vessel according to the first aspect, wherein in the survey mode, the tower is provided above a moonpool that passes through the vessel from top to bottom.

[0010] A third aspect of the present invention is a multi-purpose vessel according to the first or second aspect, wherein in the anchor handling mode, a non-watertight bottom cover is attached to the bottom of the moonpool that passes through the vessel from top to bottom.

[0011] A fourth aspect of the present invention is a multi-purpose vessel according to any one of the first to third aspects, wherein in the maintenance mode, an upper cover to which the gangway is fixed is positioned so as to cover the top of a moonpool that passes vertically through the hull. [Effects of the Invention]

[0012] According to the multi-function ship according to the above aspect of the present invention, it is possible to achieve both cost reduction and mobility in the construction and maintenance of a floating offshore wind power generation facility. [Brief explanation of the drawings]

[0013] [Figure 1] 1A and 1B are a cross-sectional view and a plan view, respectively, of a multi-functional vessel in a survey mode according to an embodiment of the present invention; [Figure 2] 1A and 1B are a cross-sectional view and a plan view, respectively, of a multifunctional vessel in anchor handling mode according to an embodiment of the present invention; [Figure 3] 1A and 1B are a cross-sectional view and a plan view, respectively, of a multi-purpose vessel in construction mode according to an embodiment of the present invention. [Figure 4] 1A and 1B are a cross-sectional view and a plan view, respectively, of a multi-function ship in a maintenance mode according to an embodiment of the present invention; [Figure 5] 1 is a schematic diagram of a floating offshore wind power generation facility. [Figure 6] FIG. 10 is a diagram illustrating a survey process using a multifunctional vessel in survey mode. [Figure 7] FIG. 10 is a diagram illustrating the transport phase using a multifunctional vessel in anchor handling mode. [Figure 8] FIG. 10 is a diagram illustrating a construction process using a multi-function ship in construction mode. [Figure 9] FIG. 10 is a diagram illustrating how the multi-function ship is switched to maintenance mode. DETAILED DESCRIPTION OF THE INVENTION

[0014] The multifunctional ship of this embodiment will be described below with reference to the drawings. The multi-function vessel 10 is configured to be switchable among a survey mode M1 (Fig. 1), an anchor handling mode M2 ​​(Fig. 2), a construction mode M3 (Fig. 3), and a maintenance mode M4 (Fig. 4). The multi-function vessel 10 has a moonpool 16 that passes through the hull 10a from top to bottom.

[0015] The multi-function vessel 10 is capable of carrying out various processes for constructing and maintaining a floating offshore wind power generation facility (hereinafter simply referred to as the power generation facility 1) as shown in FIG. 5. The power generation facility 1 generally comprises a floating structure 1a, a pillar 1b, a wind turbine 1c, etc. The pillar 1b is supported by the floating structure 1a. The wind turbine 1c is attached to the top of the pillar 1b. The floating structure 1a is moored to the seabed G by a number of anchors 1d and chains 1e.

[0016] As shown in FIG. 1, in survey mode M1, a turret 12 is mounted on the deck 11. The turret 12 is positioned above the moonpool 16. In survey mode M1, the multifunctional vessel 10 performs a survey process. Specifically, as shown in FIG. 6, an observation survey pile 20 (also called a cone) is supported by the turret 12, and the observation survey pile 20 is dropped into the water through the moonpool 16. The observation survey pile 20 is equipped with various sensors (load cells, water pressure gauges, etc.) for surveying the ground on the seabed G. By penetrating the observation survey pile 20 into the seabed G, data related to the ground, such as tip resistance, skin friction, and water pressure, can be obtained.

[0017] As shown in Figure 2, in anchor handling mode M2, multiple anchors 1d can be placed on the deck 11. Also, a chain 1e used together with the anchor 1d is stored in a storage space 15 (shaded area in Figure 2(a)) below the deck 11. The storage space 15 may include a moonpool 16. Or, the storage space 15 may be the moonpool 16 itself. In other words, the chain 1e may be stored only in the moonpool 16, or the chain 1e may be stored in a storage space 15 other than the moonpool 16. Or, cargo other than the chain 1e may be stored in the storage space 15.

[0018] As shown in Figure 7, in anchor handling mode M2, a bottom cover 17 is attached to the bottom of the moonpool 16. Therefore, even if a payload such as a chain 1e is stored in the moonpool 16, the payload can be prevented from falling into the water. In other words, the moonpool 16 can be used as a storage space 15 for storing the payload. The bottom cover 17 may be watertight, but it is more preferable that it is not watertight. By making the bottom cover 17 non-watertight, the structure of the bottom of the moonpool 16 for attaching the bottom cover 17 can be simplified. Furthermore, since the chain 1e is used underwater, there is no problem if it gets wet during transportation.

[0019] The multi-function vessel 10 is equipped with a crane 10b for grasping and moving the anchor 1d, a winch 10c for extending the chain 1e, and the like. In anchor handling mode M2, the multi-function vessel 10 transports the anchor 1d and chain 1e from a port or the like to the construction site of the power generation facility 1. Furthermore, the anchor 1d is installed underwater while extending the chain 1e. At this time, since the rafters 12 and the like used in other modes are not on the deck 11, more anchors 1d can be placed on the deck 11. In addition, the chain 1e can be stored in the storage space 15, which includes the moonpool 16, thereby reducing dead space.

[0020] In this way, by being able to load more anchors 1d and chains 1e, the number of times the multi-function vessel 10 makes round trips between a port or the like and the construction site for transportation can be reduced. The crane 10b and winch 10c used to operate the anchors 1d and chains 1e are small in size. Therefore, the crane 10b and winch 10c may be mounted on the multi-function vessel 10 not only in the anchor handling mode M2, but also in the survey mode M1, construction mode M3, and maintenance mode M4. The crane 10b and winch 10c can also be used in the survey process, construction process, and maintenance process.

[0021] As shown in FIG. 3, in construction mode M3, a construction crane 13 is mounted on the deck 11. The construction crane 13 grasps and moves a suction pile 19. The suction pile 19 is fixed to the seabed G. The suction pile 19 and the floating structure 1a are moored by a chain 1e. This prevents the power generation facility 1 from being carried away by ocean currents, etc. Note that, to moor the power generation facility 1 to the seabed G, the anchor 1d and the suction pile 19 may be used together, or only one of the anchor 1d and the suction pile 19 may be used. Note that the suction pile 19 can also be referred to as a suction anchor.

[0022] The construction crane 13 may throw the suction pile 19 into the water from the side of the hull 10a. Alternatively, as shown in Figure 8, the suction pile 19 may be thrown into the water through a moonpool 16. As shown in Figure 3, the construction crane 13 is larger than the crane 10b used to operate the anchor 1d, etc., and occupies a large area on the deck 11. For this reason, it is preferable to equip the multi-purpose vessel 10 with the construction crane 13 when carrying out construction work, and not to equip it with the construction crane 13 at other times.

[0023] As shown in Fig. 4, in maintenance mode M4, a gangway 14 is installed on the deck 11. The gangway 14 is equipped with a movable ladder. After the power generation facility 1 is constructed, the gangway 14 is used by workers to transfer from the hull 10a to the power generation facility 1 when performing work such as maintenance and inspection.

[0024] The tower 12, the construction crane 13, and the gangway 14 are detachable from the deck 11. In other words, by attaching and detaching the tower 12, the construction crane 13, and the gangway 14 to and from the deck 11, the modes M1 to M4 can be switched.

[0025] Next, a method for investigating, constructing, and maintaining the power generation facility 1 using the multifunctional ship 10 will be described.

[0026] When constructing the power generation facility 1, an investigation process is first carried out. In the investigation process, a ground survey of the seabed G at the planned construction site is carried out. At this time, the multi-function vessel 10 is in investigation mode M1, and a scaffold 12 is installed on the deck 11. In the investigation process, the scaffold 12 is used to penetrate an observation survey pile 20 into the seabed G, and various data is acquired (see Figure 6).

[0027] Next, the anchor handling process is performed. The anchor handling process is divided into a transportation phase and an installation phase. In both the transportation phase and the installation phase, the multifunctional vessel 10 is set to anchor handling mode M2. To switch from survey mode M1 to anchor handling mode M2, the yacht 12 is removed from the deck 11 at a port or the like.

[0028] In the transportation phase, the anchor 1d and chain 1e for mooring the power generation facility 1 are transported to the planned construction site. At this time, for example, the chain 1e is stored in the storage space 15, and the anchor 1d is placed on the deck 11. However, the chain 1e may also be placed on the deck 11, or the anchor 1d may be stored in the storage space 15. Furthermore, in the transportation phase, components such as the floating structure 1a may be towed. In the installation phase, the anchor 1d is installed on the seabed G, and the chain 1e is extended.

[0029] Next, the construction process is carried out. At this time, the multifunctional vessel 10 is in construction mode M3, and the construction crane 13 is installed on the deck 11. To switch from anchor handling mode M2 ​​to construction mode M3, the construction crane 13 is attached to the deck 11 at a port or the like. In the construction process, the power generation facility 1 is constructed at the planned construction site. That is, the floating structure 1a is assembled, the columns 1b and wind turbines 1c are fixed to the floating structure 1a, the suction piles 19 are fixed to the seabed G, and the floating structure 1a is moored to the anchors 1d or suction piles 19. The construction crane 13 can be used in these operations. When the construction of the power generation facility 1 is completed, wind power generation begins.

[0030] Next, the maintenance process is performed. At this time, the multifunctional ship 10 is in maintenance mode M4, with the gangway 14 installed on the deck 11. To switch from construction mode M3 to maintenance mode M4, the construction crane 13 is removed from the deck 11 at a port or the like, and the gangway 14 is installed. Figure 9 shows an example of how the gangway 14 is installed on the deck 11. In the example of Figure 9, the gangway 14 is fixed to a top cover 18 for closing the moonpool 16. By attaching the top cover 18 together with the gangway 14 to the top of the moonpool 16 at a port or the like, maintenance mode M4 can be easily achieved. In this example, the gangway 14 is located above the moonpool 16. However, as shown in Figure 4, the gangway 14 may also be located away from the moonpool 16.

[0031] As described above, the multifunctional vessel 10 of this embodiment can be switched between survey mode M1, anchor handling mode M2, construction mode M3, and maintenance mode M4. In survey mode M1, the rafter 12 is attached to the deck 11. In anchor handling mode M2, the anchor 1d of the power generation facility 1 can be placed on the deck 11, and the chain 1e of the power generation facility 1 can be stored in the storage space 15 below the deck 11, allowing the anchor 1d to be installed on the seabed G and the chain 1e to be extended. In construction mode M3, a construction crane 13 is attached to the deck 11. In maintenance mode M4, a gangway 14 is attached to the deck 11.

[0032] According to this embodiment, a single multi-function vessel 10 can perform survey, transportation, construction, and maintenance processes by switching between survey mode M1, anchor handling mode M2, construction mode M3, and maintenance mode M4. Therefore, costs can be reduced compared to preparing multiple dedicated vessels for each process when constructing and maintaining the power generation facility 1. Furthermore, if multiple dedicated vessels were prepared, the dedicated vessels would be idle during periods when the vessels were not performing their assigned processes, resulting in a reduced availability rate. In response to this issue, the multi-function vessel 10 can perform multiple processes, thereby reducing idle periods and improving availability. Furthermore, compared to a vessel equipped with a yacht 12, construction crane 13, gangway 14, and storage space 15, the hull 10a can be made smaller and mobility can be ensured.

[0033] In addition, in the survey mode M1, a tower 12 is provided above a moonpool 16 that penetrates the hull 10a from top to bottom. Using this tower 12, an observation survey pile 20 can be inserted into the seabed G to carry out the survey process.

[0034] In anchor handling mode M2, a non-watertight bottom cover 17 may be attached to the bottom of the moonpool 16 that passes vertically through the hull 10a. This allows the moonpool 16 to be used as a space for storing the chain 1e. Furthermore, compared to when the bottom cover 17 is watertight, the structure of the attachment portion of the bottom cover 17 can be simplified.

[0035] Furthermore, in maintenance mode M4, a top cover 18 to which the gangway 14 is fixed may be arranged so as to cover the top of the moonpool 16 that passes vertically through the hull. With this configuration, the top cover 18 can be used as a part for attaching the gangway 14 to the hull 10a. In other words, when switching the multifunctional vessel 10 between maintenance mode M4 and the other modes M1 to M3, the top cover 18 can be replaced. This makes mode switching easier.

[0036] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0037] For example, in the above embodiment, the modes are switched in the order of survey mode M1, anchor handling mode M2, construction mode M3, and maintenance mode M4. However, this switching order can be changed. For example, in order to construct and maintain multiple power generation facilities 1 in parallel, the modes of the multifunctional vessel 10 may be flexibly switched. Furthermore, construction mode M3 does not necessarily have to be included, and may be configured to be implemented appropriately as needed.

[0038] In addition, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, and the above-described embodiments and variations may be combined as appropriate, without departing from the spirit of the present invention. [Explanation of symbols]

[0039] 1d...Anchor 1e...Chain 10...Multi-function vessel 10a...Hull 10b...Crane 11...Deck 12...Scaffolding 13...Construction crane 14...Gangway 15...Storage space 16...Moon pool 17...Bottom cover 18...Top cover G...Seabed

Claims

1. Survey mode with a yagura attached to the deck, an anchor handling mode in which an anchor of the offshore wind power generation facility can be placed on the deck, a chain of the offshore wind power generation facility can be stored in a storage space below the deck, and the anchor can be installed on the seabed and the chain can be stretched; A multi-function ship that can be switched between a maintenance mode and a mode in which a gangway is installed on the deck.

2. 2. The multi-function vessel according to claim 1, wherein in the survey mode, the yacht is provided above a moonpool that passes vertically through the hull of the vessel.

3. 3. The multi-purpose vessel according to claim 1, wherein in the anchor handling mode, a non-watertight bottom cover is attached to the bottom of a moonpool that passes through the vessel from top to bottom.

4. 3. The multi-function vessel according to claim 1, wherein in the maintenance mode, an upper cover to which the gangway is fixed is positioned so as to cover an upper portion of a moonpool that passes vertically through the vessel body.

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