Vessel and method for handling a power cable

Abstract

A method of handling a power cable (10) on a vessel (18), the method comprising the following steps in any order: pulling (520) an end part (12) of the power cable (10) onto the vessel (18) from a first area (20) next to a first side (30) of the vessel (18); and guiding (530) the end part (12) of the power cable (10) across and overboard the vessel (18) to a second area (22) next to a second side (32) of the vessel (18), the second side (32) being opposite the first side (30) of the vessel (18). A vessel for handling a power cable (10), comprising a handling system (100) for the power cable (10), the handling system (100) comprising a first guide (110) positioned at a first side (30) of the vessel (18); and a lifting device (200) for handling the power cable (10); wherein the vessel (18) comprises a second guide (300) for handling the power cable (10), the second guide (300) being movable towards and away in relation to the handling system (100), and movable in an away position where the power cable (10) can be guided overboard the vessel (18) at a second side (32) of the vessel (18), the second side (32) being opposite the first side (30) of the vessel (18); and wherein the first guide (110) and the second guide (300) are configured for guiding the power cable (10) across the vessel (18) from overboard the first side (30) of the vessel (18) to overboard the second side (32) of the vessel (18).

Description

[0001] VESSEL AND METHOD FOR HANDLING A POWER CABLE

[0002] Technical Field

[0003] The present disclosure relates to a vessel for handling a power cable, and a method of handling a power cable on a vessel. More particularly, the present disclosure relates to handling an inter array power cable for floating offshore structures, and how to retrieve a part of the power cable from a wet-parked condition so that ancillaries can be mounted to the power cable.

[0004] Background

[0005] Power cables are sometimes stored subsea, this is also known as a wet- parked power cable. Such a wet-parked power cable may be retrieved so that ancillaries can be mounted to the power cable. An end of the power cable is retrieved from the sea to a vessel so that ancillaries, for example boys, clamps, protections, etc., can be installed on the power cable. Counting from the end of the power cable it may be necessary to retrieve 200 meters, or more or less, of the power cable. This length of the power cable must be presented on the vessels work area so that the ancillaries can be installed on the power cable. Thereafter the power cable may be wet-parked again. This may be done for each end of the power cable. Such retrieval of the power cable onto the vessel is made by using a reel. Using a reel on the vessel is time consuming, takes space on the deck of the vessel, and requires additional staff handling the reel. The size of the reel limits the length of the power cable that can be reeled up.

[0006] It is a problem how to retrieve a power cable onto a vessel, especially for the length that may be required. It is desirable to keep costs low for retrieving the power cable, and to do it in an efficient way. A further consideration is to ensure not to damage the power cable while handling the power cable. Any solution must provide a good area to work on for installing ancillaries. Further technical problems includes that the power cable terminations often do not go through a tensioner, the length that must be retrieved and the depth of the sea where the vessel operates.

[0007] It is desirable that any solution can use an existing vessel without too much of a change or need to rebuild the deck and / or the vessel. It is a problem to comply with the relevant regulation technically and in a cost effective manner. It is further a problem to avoid damage to the power cable and any part of the vessel. The power cable is normally heavy, especially when pulling of the power cable up from the sea. Retrieving a long part of the power cable results in complicated handling of that length on the vessel. Any solution needs to be flexible and fit different types of power cables.

[0008] A further technical problem is that any part of handling a power cable on a vessel must be safe and function without a possibility to fail, fulfil technical and legal requirements, and be easy to use. It is desirable that any solution is simple, not expensive to produce, and is reliable. It is a further technical problem to avoid cumbersome arrangements that are expensive to realise.

[0009] Summary of the Invention

[0010] It is an object of the present invention to provide a vessel for handling a power cable, and a method of handling a power cable. This object can be achieved by the features as defined by the independent claims. Further enhancements are characterized by the dependent claims. The invention is defined by the claims.

[0011] According to one embodiment, a method of handling a power cable 10 on a vessel 18 is disclosed. The method comprising the following steps in any order: pulling 520 an end part 12 of the power cable 10 onto the vessel 18 from a first area 20 next to a first side 30 of the vessel 18; and guiding 530 the end part 12 of the power cable 10 across and overboard the vessel 18 to a second area 22 next to a second side 32 of the vessel 18, the second side 32 being opposite the first side 30 of the vessel 18.

[0012] The method may further comprise the following steps in order: taking 510 a wet-parked power cable 10 and pulling 520 the end part 12 of the wet-parked power cable 10 from the first area 20 next to the first side 30 of the vessel 18; guiding 530 the end part 12 of the power cable 10 across and overboard the vessel 18 to the second area 22 next to the second side 32 of the vessel 18; working 560 on at least a part of the end part 12 of the power cable 10; and wet-parking 570 the power cable 10 back into the sea the first area 20 next to the first side 30 of the vessel 18.

[0013] The method may further comprise using the vessel 18 according to any one of the embodiments disclosed herein. The method further comprising: attaching an end 11 of the power cable 10 to the lifting device 200; using the first guide 110 when pulling 520 the end part 12 of the power cable 10 onto the vessel 18 from a first area 20 next to a first side 30 of the vessel 18; using the second guide 300 when guiding 530 the end part 12 of the power cable 10 across the vessel 18 and overboard the vessel 18 to the second area 22 next to the second side 32 of the vessel 18; moving 540 the lifting device 200 on the vessel 18 between the first guide 100 and the second guide 300; holding 550 the end 11 of the power cable 10 with the lifting device 200 overboard the second side 32 of the vessel 18, thereby allowing the end part 12 of the power cable 10 to be guided from overboard on one side 30 of the vessel 18 to overboard to an opposite side 32 of the vessel 18 and up to the lifting device 200 while working on at least a part of the end part 12 of the power cable 10.

[0014] The method may further comprise moving the second guide 300 towards or away from the first guide 100. The method may further comprise using the second guide 300 to guide a wire 14 connectable to the power cable 10.

[0015] According to one embodiment, a vessel for handling a power cable 10 is disclosed. The vessel comprises: a handling system 100 for the power cable 10, the handling system 100 comprising a first guide 110 positioned at a first side 30 of the vessel 18; and a lifting device 200 for handling the power cable 10; wherein the vessel 18 comprises a second guide 300 for handling the power cable 10, the second guide 300 being movable towards and away in relation to the handling system 100, and movable in an away position where the power cable 10 can be guided overboard the vessel 18 at a second side 32 of the vessel 18, the second side 32 being opposite the first side 30 of the vessel 18; and wherein the first guide 110 and the second guide 300 are configured for guiding the power cable 10 across the vessel 18 from overboard the first side 30 of the vessel 18 to overboard the second side 32 of the vessel 18.

[0016] According to one embodiment, the second guide 300 may be moved to reach overboard the vessel 18. According to one embodiment, the lifting device 200 may be movably arranged on the vessel 18 for movement between the first guide 110 and the second guide 300, and may be configured to reach overboard the vessel 18 on at least one of the first side 30 and the second side 32 of the vessel 18.

[0017] According to one embodiment, the lifting device 200 may be a derrick, preferably an A-frame derrick, transferring vertical and horizontal loads. The second guide 300 may be one or more of a wheel, a reel, a sheave, and a chute. The second guide 300 may be configured, in addition to handling the power cable 10, for guiding a wire 14 connectable to the power cable 10. The wheel may be a circular frame arrangement revolvable around an axis supporting, guiding, the power cable 10 on its outer surface with radial protrusions for preventing the power cable 10 sliding of the outer surface. Further examples of the second guide 300 are a drum, or a reel, for the power cable 10.

[0018] According to one embodiment, the vessel may further comprise a reel 15 for the wire 14. A working space may be provided on a deck of the vessel 18 between the handling system 100 and the second guide 300 for attaching one or more of the following to the power cable 10: a bend restrictor, a connector, a clamp, a sensor, a buoyancy element, a ballast element, an anchor, a termination element, and a protective element. The handling system 100 may further comprise a tensioner 120.

[0019] According to one embodiment, the first guide 110 may be positioned at the first side 30 with an angle to the first side 30, and the second guide 300 may be positioned at the second side 32 with the same angle to the second side 32.

[0020] At least one of the above embodiments provides one or more solutions to the problems and disadvantages with the background art. Other technical advantages of the present disclosure will be readily apparent to one skilled in the art from the following description and claims. Various embodiments of the present application obtain only a subset of the advantages set forth. No one advantage is critical to the embodiments. Any disclosed embodiment may be technically combined with any other disclosed embodiment or embodiments.

[0021] Brief Description of the Drawings

[0022] The accompanying drawings illustrate presently exemplary embodiments of the disclosure and serve to explain, by way of example, the principles of the disclosure.

[0023] Fig 1 is a diagrammatic and schematic illustration of a cross section of a vessel for handling a power cable according to an exemplary embodiment of the disclosure;

[0024] Fig 2 is a diagrammatic and schematic illustration of a plan view of a vessel for handling a power cable according to an exemplary embodiment of the disclosure;

[0025] Fig 3 is a diagrammatic and schematic illustration of a cross section of a vessel for handling a power cable according to an exemplary embodiment of the disclosure; Fig 4 is a diagrammatic and schematic illustration of a cross section of a vessel for handling a power cable according to an exemplary embodiment of the disclosure;

[0026] Fig 5 is a diagrammatic and schematic illustration of a part of a vessel for handling a power cable according to an exemplary embodiment of the disclosure;

[0027] Fig 6 is a diagrammatic and schematic illustration of a part of a vessel for handling a power cable according to an exemplary embodiment of the disclosure;

[0028] Fig 7 is a diagrammatic and schematic illustration of a cross section of a vessel for handling a power cable according to an exemplary embodiment of the disclosure; and

[0029] Fig 8 is a diagrammatic illustration of a method of handling a power cable on a vessel according to an exemplary embodiment of the disclosure.

[0030] Detailed Description

[0031] Figures 1 to 7 illustrate exemplary embodiments of a vessel for handling a power cable according to an exemplary embodiment of the disclosure. Figures 1 , 3, 4, and 7 are cross sections of the vessel perpendicular to a direction from bow to stern. Details of the vessel have been omitted for clarity reasons. Figure 2 is a schematic plan view of a part of a deck of a vessel according to an exemplary embodiment of the disclosure. Figure 8 illustrated a flow chart of a method of handling a power cable on a vessel according to an exemplary embodiment of the disclosure.

[0032] Turning to figures 1 , 3, 4, and 7, vessels and methods for handling a power cable according to exemplary embodiments of the disclosure are illustrated. The vessel 18 is shown in a cut, perpendicular to the horizontal axis of the vessel, i.e. perpendicular to a direction from bow to stern. For clarity purposes the vessel 18 in figures 1, 3, 4, and 7 has not been hachured. The vessel 18 may be a ship, a boat, or a floating structure, with or without its own means of transportation. Figure 1 shows the vessel 18 at sea with the sea surface 16 and the seabed 17. A first area 20 is next to a first side 30 of the vessel 18. The first area 20 is a body of sea water next to the first side 30 of the vessel 18. A second area 22 is next to a second side 32 of the vessel 18. The second area 22 is a body of sea water next to the second side 32 of the vessel 18. The first area 20 is opposite the second area 22 with the vessel 18 being in between the two areas 20, 22. The first side 30 of the vessel 18 is opposite the second side 32 of the vessel 18. The first side 30 and the second side 32 are part of the vessel 18, while the first area 20 and the second area 22 are seawater areas next to the vessel 18.

[0033] With reference to the figures, especially figure 8, at least one embodiment described herein provides a method for handling a power cable 10 on a vessel 18. The power cable 10 may be an inter array power cable to be used for a floating offshore structure, for example, with a wind turbine. The power cable 10 may be an electrical power cable, an assembly of one or more electrical conductors, for example held together with an overall sheath. The power cable 10 may be used for transmission of electrical power.

[0034] The method of handling the power cable 10 on the vessel 18 comprises the following steps taken in any order: pulling 520 an end part 12 of the power cable 10 onto the vessel 18 from a first area 20 next to a first side 30 of the vessel 18; and guiding 530 the end part 12 of the power cable 10 across and overboard the vessel 18 to a second area 22 next to a second side 32 of the vessel 18, the second side 32 being opposite the first side 30 of the vessel 18. Preferably the pulling 520 is done before the guiding 530.

[0035] The power cable 10 has an end 11. The end 11 of the power cable 10 may have an end termination. Only a part of the power cable 10 is pulled up onto the vessel 18. The part pulled up is the end part 12. This end part 12 has been marked with an arrow and the reference number 12 in figures 1 , 3, and 7. In these figures the end part 12 is the part of the power cable 10 from the arrow and the reference number 12 to the end 11. The end part 12 is not the whole power cable 10. For example, the end part 12 may be just a few hundred meters from an end 11 of the power cable 10. The end part 12 may be the part of the power cable 10 counting from where the power cable 10 can be accessed from a handling system 100, especially from a balcony 130 of the handling system 100, until the end 11.

[0036] The end part 12 of the power cable 10 is pulled up onto the vessel 18, for example by a lifting device 200 lifting up the end 11 of the power cable 10 from the first area 20. The power cable 10 is then guided across the vessel 18 to an opposite side, and overboard the opposite side of the vessel 18, i.e. overboard the vessel 18 to the second area 22. The power cable 10 may hang overboard with the end 11 in the sea as illustrated in figure 3, or the power cable 10 may hang overboard and the end 11 may be kept on the vessel 18, for example the end 11 may be held by the lifting device 200 as illustrated in figure 1 or kept at the vessel deck. For example, as illustrated in figure 2, the power cable 10 may extend up from the first area 20 next to the vessel 18 via the handling system 100, extend over the vessel to the second guide 300, extend overboard to the second area 22 next to the vessel 18, and extend back up on the vessel 18 where an attachment 140 may hold the end 11 of the power cable 10 on the deck of the vessel 18. The attachment 140 may comprise a winch with a winch wire connected to the end 11 of the power cable 11. In both cases the end part 12 of the power cable 10 may go from the sea on one side of the vessel 18, across the vessel 18, and into the sea on the opposite side of the vessel 18, depending how much of the power cable 10 is pulled up. The power cable 10 may cross the vessel 18 perpendicular to a direction from bow to stern, or at an angle to that direction. If the end part 12 is long, for example so long that it may touch the seabed 14 on the opposite side, then the end 11 may be held by the lifting device 200. This allows a longer end part 12 to be pulled up onto the vessel 18 and to be worked on.

[0037] As illustrated by the figures, especially figure 8, a method may comprise one or more of the following steps 510 to 570. The steps may be taken in any order as long as it makes technical sense, but preferably in the order given by figure 8.

[0038] The method may comprise taking 510 a wet-parked power cable 10 and pulling 520 the end part 12 of the wet-parked power cable 10 from the first area 20 next to the first side 30 of the vessel 18. A wet-parked power cable 10 is a power cable that is stored subsea. An end part 12 of the power cable 10 may be retrieved from the sea and taken up onto the vessel 18. This may be done by using of the lifting device 200 and the handling system 100.

[0039] The method may comprise guiding 530 the end part 12 of the power cable 10 across and overboard the vessel 18 to the second area 22 next to the second side 32 of the vessel 18. In this way the end part 12 of the power cable 10 is accessible to work on as it is guided across the deck of the vessel 18. This may be done by using one or more of the lifting device 200, the handling system 100, the first guide 110, and the second guide 300. This is also explained in more detail hereinafter.

[0040] The method may comprise working 560 on at least a part of the end part 12 of the power cable 10. When the end part 12 of the power cable 10 is on the deck of the vessel 18, then work can be done on the cable. A working space may be provided on a deck of the vessel 18. The work may comprise attaching, or removing, one or more of the following to the power cable 10: a bend restrictor, a connector, a clamp, a sensor, a buoyancy element, a ballast element, an anchor, a termination element, and a protective element. The method may comprise wet-parking 570 the power cable 10 back into the first area 20 next to the first side 30 of the vessel 18. The power cable 10 may be put back into storage subsea. This may best be done on the same side of the vessel 18 where the power cable 10 was pulled up. This side is preferably the first side 30 of the vessel 18, the side 30 where the handling system 100 is positioned.

[0041] As illustrated by the figures, especially figure 8, a method of handling a power cable 10 on a vessel 18 is disclosed according any one of the embodiments disclosed herein. The method may use the vessel 18 according to any one of the embodiments described herein. The method may comprise one or more of the steps 510 to 570 and / or other steps mentioned herein. The steps may be taken in any order as long as it makes technical sense.

[0042] The method may comprise attaching an end 11 of the power cable 10 to the lifting device 200. In this way the power cable 10 may be handled and moved about on board the vessel 18. In this way the power cable 10 may be held overboard so that the power cable 10 can go overboard from the deck of the vessel 18 to the second area 22, and make a U-turn up to the lifting device 200, as best illustrated in figure 1. In this way the power cable 10 may be held on board the vessel 18 so that the power cable 10 can be held on the deck of the vessel 18, as best illustrated in figure 7.

[0043] The method may comprise using the first guide 110 when pulling 520 the end part 12 of the power cable 10 onto the vessel 18 from a first area 20 next to a first side 30 of the vessel 18. This may include guiding the power cable 10 through the first guide 110 and the tensioner 120 of the handling system 100.

[0044] The method may comprise using the second guide 300 when guiding 530 the end part 12 of the power cable 10 across the vessel 18 and overboard the vessel 18 to the second area 22 next to the second side 32 of the vessel 18. In this way the power cable 10 goes via the second guide 300 overboard the vessel 18. The second guide 300 may be one, or more, of a wheel, a reel, a sheave, and a chute. The use of a chute would be an inexpensive and efficient solution.

[0045] The method may comprise moving 540 the lifting device 200 on the vessel 18 between the first guide 100 and the second guide 300. The lifting device 200 may be movable on the deck of the vessel 18 between the first guide 100 and the second guide 300. An example of this movement is illustrated with arrow 202 in figure 2. This allows the lifting device 200 to hold the end 11 of the power cable 10, or any other part of the power cable 10, and handle the power cable 10 by moving it on board the vessel 18, but also moving the power cable 10 overboard.

[0046] The method may comprise holding 550 the end 11 of the power cable 10 with the lifting device 200 overboard the second side 32 of the vessel 18, thereby allowing the end part 12 of the power cable 10 to be guided from overboard on one side 30 of the vessel 18 to overboard to an opposite side 32 of the vessel 18 and up to the lifting device 200 while working on at least a part of the end part 12 of the power cable 10. This may best be taken from figures 1 to 3, 7, and 8, and is further described herein.

[0047] According to one embodiment, a method may comprise moving the second guide 300 towards or away from the first guide 100. The second guide 300 may be moved so that the second guide is substantially on board the vessel, see for example figure 7. Figures 2 and 4 show two positions of the second guide 300, one position is more towards the first guide 100 with the second guide 300 being substantially on board the vessel 18, the other position is more away from the first guide 100 with the second guide 300 being substantially overboard the vessel 18. In the latter position, the power cable 10 may be guided out and away from the second side 32 into the second area 22, such that the power cable 10 does not come in contact with the second side 32 of the vessel 18.

[0048] According to one embodiment, a method may comprise using the second guide 300 to guide a wire 14 connectable to the power cable 10. The wire 14 may be a hold-back wire connectable to the power cable 10. The wire 14 may be used when handling the power cable 10 and the tensioner 120 or the lifting device 200 may have to let go of, or change hold of, the power cable 10. A reel 15 may be used for reeling the wire 14. The reel 15 may be arranged on board the vessel 18. This may best be taken from figure 7.

[0049] With reference to the figures, embodiments of vessels 18 for handling a power cable 10 are disclosed. According to at least one embodiment, a vessel for handling a power cable 10, comprises a handling system 100 for the power cable 10 and a lifting device 200 for handling the power cable 10. The handling system 100 comprises a first guide 110 positioned at a first side 30 of the vessel 18. The positioning may allow the first guide 110 to reach overboard the first side 30 of the vessel 18. This may best be taken from figures 1 to 4, and 7. The handling system 100 may include a tensioner 120. The lifting device 200 may handle the end 11 of the power cable 10, the end part 12, or any other part of the power cable 10. More details of the lifting device 200 is given below.

[0050] The vessel 18 comprises a second guide 300 for handling the power cable 10. The second guide 300 is movable towards and away in relation to the handling system 100. The second guide 300 is movable in an away position where the power cable 10 can be guided overboard the vessel 18 at a second side 32 of the vessel 18. The second side 32 is opposite the first side 30 of the vessel 18. The first guide 110 and the second guide 300 are configured for guiding the power cable 10 across the vessel 20 from overboard the first side 30 of the vessel 18 to overboard the second side 32 of the vessel 18. The end part 12 of the power cable 10 is thus guided via the first guide 110 from the area 20 on one side 30 of the vessel 18, across the vessel’s deck, to overboard via the second guide 300 into the area 22 on the opposite side 32 of the vessel 18. This is illustrated in figures 1 and 3.

[0051] The second guide 300 may be movable to reach overboard the vessel 18. The second guide 300 may be movable substantially overboard the vessel 18. The second guide 300 may be movable such that the power cable 10 is guided overboard the vessel 18, for example down and into the sea, into the second area 22. The second guide 300 may guide the power cable 10 away from the deck and / or away from the second side 32 of the vessel 18. This allows the power cable 10 to be protected and not hitting the second side 32 of the vessel 18.

[0052] With reference to the figures, especially figures 1 and 2, the handling system 100 includes the first guide 110 and may include a tensioner 120. The handling system 100 may have the first guide 110 to receive the end part 12 of a wet-parked power cable 10. That power cable 10 may then be pulled up via the first guide 110 by, for example, the lifting device 200. The end part 12 of the power cable 10 may then optionally go through the tensioner 120. The end part 12 of the power cable 10 may then be pulled by the lifting device 200 to the second guide 300 and be guided overboard the vessel 18. The end 11 of the power cable 10 may hang freely into the sea in the second area 22 next to the second side 32 of the vessel 18. This may be best taken from figure 3. Alternatively, the lifting device 200 may hold the end 11 of the power cable 10 so that the power cable 10 makes a U-turn in the second area 22 next to the second side 32 of the vessel 18. This may be best taken from figure 3. Alternatively, another device may hold the end 11 of the power cable 10 on the vessel 18. For example, as best illustrated in figure 2, the end 11 of the power cable 10 may be secured to the attachment 140 on the vessel 18. The attachment 140 may comprise a winch and a winch wire and / or a holder for holding the end of the power cable 10.

[0053] Figure 2 shows the layout of the handling system 100, the lifting device 200, and the second guide 300 according to one example showing the general principal. Following the layout in the direction of a power cable pulled up from the sea, the first guide 110 may reach overboard the first side 30. The tensioner 120 may be connected, or very close to the first guide 110. Thereafter there may be space on the deck of the vessel 18 to do work on the power cable 10. The second guide 300 may be at the opposite side, the second side 32, of the vessel 18. The second guide 300 may be moved between at least two positions as illustrated in figures 2 and 4. One position is substantially on the deck of the vessel 18, such that the power cable 10 is not guided overboard the vessel 18. The other position is such that the second guide can reach, guide the power cable 10, overboard the vessel 18. Both of these two positions are illustrated in figures 2 and 4, while figures 1 and 3 show the second guide 300 reaching overboard the vessel 18, and figure 7 shows the second guide 300 substantially on the vessel 18.

[0054] The lifting device 200 may be movably arranged on the vessel 18 for movement 202 between the first guide 110 and the second guide 300. The lifting device 200 may be configured to reach overboard the vessel 18 on at least one of the first side 30 and the second side 32 of the vessel 18. The lifting device 200 may reach overboard at each of the two opposite sides 30, 32 of the vessel 18. The lifting device 200 may be movable in the horizontal direction between the first guide 110 and the second guide 300. The movement is illustrated with arrow 202 in figure 2. The movement is in the plane of the deck. For example, the lifting device 200 may run on rails on the deck or similar. The lifting device 200, or a stationary device, on the vessel 18 may hold the end 11 of the power cable 10 stationary on the vessel 18.

[0055] With reference to figure 6, the lifting device 200 may be a derrick or a crane. For example, an A-frame derrick. The lifting device 200 may be configured to transfer vertical and horizontal loads that arises when handling the power cable 10. Such a configuration may be an A-frame derrick or similar derricks. An A-frame derrick may have a boom hinged from a cross member between the bottom ends of two upright members spread apart at the lower ends and joined at the top; the boom point secured to the junction of the side members, and the side members are braced or guyed from this junction point. The lifting device 200 may comprise at least one guyed mast 220, as in a gin pole derrick, which may be articulated over a load by adjusting its guys. The lifting device 200 may have at least two components, either a guyed mast or self-supporting tower, and a boom hinged at its base to provide articulation, as in a stiffleg derrick. The lifting device 200 may be controlled by three or four lines connected to the top of a mast, which allow it both to move laterally and up and down. To lift a load, a separate line may run up and over the mast with a hook 230 on its free end, as with a crane. The lifting device 200 may be a basket derrick, a breast derrick, a Chicago boom derrick, a gin pole derrick, a guy derrick, a shearleg derrick, or a stiffleg derrick. The derrick may be supported by a frame 210. The frame 210 may be movably arranged on the deck of the vessel 18, for example running on rails.

[0056] The second guide 300 may be one or more of a wheel, a sheave, and a chute. Each of the first guide 100 and the second guide 300 may guide the power cable 90 degrees, for example from a vertical direction to a horizontal direction, or from a horizontal direction to a vertical direction.

[0057] As best illustrated in figure 7, the second guide 300 may be configured, in addition to handling the power cable 10, for guiding a wire 14. The wire 14 may be connectable to the power cable 10. The wire 14 may be a hold-back wire connectable to the power cable 10. The vessel 18 may further comprise a reel 15 for the wire 14. The reel 15 may be positioned within the handling system, for example in the frame of the handling system 100. The second guide 300 may comprise a guide for the power cable 10 and a guide for the wire 14, both guides being separate guides but connected to each other for support.

[0058] As may be taken from the figures, the vessel 18 may comprise a working space, an area on the deck, for working on the power cable 10. The working space may be provided on a deck of the vessel 18 between the handling system 100 and the second guide 300. The working space may be used for attaching one or more of the following to the power cable 10: a bend restrictor, a connector, a clamp, a sensor, a buoyancy element, a ballast element, an anchor, a termination element, and a protective element. The lifting device 200 may be movable along the entire working space to allow the lifting device 200 to handle the power cable 10. The lifting device 200 may be outside the working space and reach over the working space.

[0059] As illustrated in figures 1-3, and 7 the handling system 100 may further comprises a tensioner 120. Figures 4 and 5 illustrate the handling system 100 without a tensioner. The tensioner 120 may be a cable mover that can move, feed, the power cable 10. The position of the handling system 100 may be at an angle 102 to the side 30 of the vessel 18. Figure 2 illustrates that the angle is 90 degrees, however the angle may be anything from 45 to 135 degrees. The second guide 300 may be in line with that angle. That is, on a vessel with, for example, a tensioner 120 in a specific angle, the second guide 300 on the opposite side of the vessel 18 may have the corresponding specific angle such that the power cable 10 is guided in a straight line across the vessel 18 from the first guide 110 via the tensioner 120 to the second guide 300. The straight line is then in the specific angle to the sides 30 and 32 of the vessel 18. In figure 2 the angle 102 is 90 degrees and the first guide 110, the tensioner 120, and the second guide 300 are all arranged perpendicular to the sides 30 and 32 of the vessel 18. The first guide 110 may be positioned at the first side 30 with an angle to the first side 30, and the second guide 300 may be positioned at the second side 32 with the same angle to the second side 32. Such an arrangement allows to easily modify an existing vessel 18 that may have a tensioner or first guide positioned at an angle, because the position of the tensioner or first guide need not to be changed.

[0060] A fourth guide may be used. The fourth guide may be placed on the deck close to the second side 32 of the vessel 18 so that the power cable makes two II- shaped turns, similar to a W-shape, instead of merely making a single U-turn in the second area 22. This would allow for a longer part of the power cable 10 to be pulled up and worked on without the power cable 10 touching the seabed 17. A similar two U-shaped configuration may be achieved with a second lifting device, or simply a stationary hook, holding the end 11 , while the lifting device 200 may lift the middle of the one U-shaped power cable and thereby making a two U-shaped configuration.

[0061] One or more of the embodiments described herein allows retrieving a wet- parked power cable 10 across and on board the vessel 18, with the power cable 10 being in the sea on two opposite sides of the vessel, so that ancillaries can be mounted to the power cable 10. An end part 12 of the power cable 10 may be retrieved from the sea onto the vessel 18 so that ancillaries, for example boys, clamps, protections, etc., can be installed on the power cable 10. The end part 12 may be 200 meters, 300 meters, or more or less. Thereafter the power cable 10 may be wet-parked again. This may be done for each end of the power cable 10.

[0062] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using the vessel for handling a power cable and performing the methods of handling a power cable on a vessel. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

[0063] List of elements

[0064] 10 power cable

[0065] 11 end of power cable

[0066] 12 end part of power cable

[0067] 14 wire

[0068] 15 reel for wire

[0069] 16 sea surface

[0070] 17 seabed

[0071] 18 vessel

[0072] 20 first area next to the vessel

[0073] 22 second area next to the vessel

[0074] 30 first side of the vessel

[0075] 32 second side of the vessel

[0076] 100 handling system

[0077] 102 angle

[0078] 110 first guide

[0079] 120 tensioner

[0080] 130 balcony

[0081] 140 attachment for power cable

[0082] 200 lifting device

[0083] 202 direction of movement of lifting device

[0084] 210 frame

[0085] 220 mast

[0086] 230 hook

[0087] 300 second guide

[0088] 510 taking a wet-parked power cable

[0089] 520 pulling the power cable onto the vessel

[0090] 530 guiding the power cable overboard the vessel moving the lifting device on the vessel holding an end of the power cable working on at least a part of the power cable wet-parking the power cable

Claims

Claims1 A vessel for handling a power cable (10), comprising a handling system (100) for the power cable (10), the handling system (100) comprising a first guide (110) positioned at a first side (30) of the vessel (18); and a lifting device (200) for handling the power cable (10); wherein the vessel (18) comprises a second guide (300) for handling the power cable (10), the second guide (300) being movable towards and away in relation to the handling system (100), and movable in an away position where the power cable (10) can be guided overboard the vessel (18) at a second side (32) of the vessel (18), the second side (32) being opposite the first side (30) of the vessel (18); and wherein the first guide (110) and the second guide (300) are configured for guiding the power cable (10) across the vessel (18) from overboard the first side (30) of the vessel (18) to overboard the second side (32) of the vessel (18).2 The vessel according to claim 1, wherein the second guide (300) can be moved to reach overboard the vessel (18).3 The vessel according to claim 1 or 2, wherein the lifting device (200) is movably arranged on the vessel (18) for movement between the first guide (110) and the second guide (300), and configured to reach overboard the vessel (18) on at least one of the first side (30) and the second side (32) of the vessel (18).4 The vessel according to any one of the claims 1 to 3, wherein the lifting device (200) is a derrick transferring vertical and horizontal loads.5 The vessel according to any one of the claims 1 to 4, wherein the second guide (300) is one or more of a wheel, a sheave, and a chute.6 The vessel according to any one of the claims 1 to 5, wherein the second guide (300) is configured, in addition to handling the power cable (10), for guiding a wire (14) connectable to the power cable (10).7 The vessel according to claim 6, further comprising a reel (15) for the wire (14).8 The vessel according to any one of the claims 1 to 7, wherein a working space is provided on a deck of the vessel (18) between the handling system (100) and the second guide (300) for attaching one or more of the following to the power cable (10): a bend restrictor, a connector, a clamp, a sensor, a buoyancy element, a ballast element, an anchor, a termination element, and a protective element.9 The vessel according to any one of the claims 1 to 8, wherein the handling system (100) further comprises a tensioner (120).10 The vessel according to any one of the claims 1 to 9, wherein the first guide (110) is positioned at the first side (30) with an angle to the first side (30), and the second guide (300) is positioned at the second side (32) with the same angle to the second side (32).11 A method of handling a power cable (10) on a vessel (18), the method comprising the following steps in any order: pulling (520) an end part (12) of the power cable (10) onto the vessel (18) from a first area (20) next to a first side (30) of the vessel (18); and guiding (530) the end part (12) of the power cable (10) across and overboard the vessel (18) to a second area (22) next to a second side (32) of the vessel (18), the second side (32) being opposite the first side (30) of the vessel (18).12 The method according to claim 11 , comprising the following steps in order: taking (510) a wet-parked power cable (10) and pulling (520) the end part(12) of the wet-parked power cable (10) from the first area (20) next to the first side (30) of the vessel (18); guiding (530) the end part (12) of the power cable (10) across and overboard the vessel (18) to the second area (22) next to the second side (32) of the vessel (18); working (560) on at least a part of the end part (12) of the power cable (10); andwet-parking (570) the power cable (10) back into the sea the first area (20) next to the first side (30) of the vessel (18).13 The method of handling a power cable (10) on a vessel (18) according any one of the claims 11 or 12, using the vessel (18) according to any one of the claims 1 to 10, the method further comprising: attaching an end (11) of the power cable (10) to the lifting device (200); using the first guide (110) when pulling (520) the end part (12) of the power cable (10) onto the vessel (18) from a first area (20) next to a first side (30) of the vessel (18); using the second guide (300) when guiding (530) the end part (12) of the power cable (10) across the vessel (18) and overboard the vessel (18) to the second area (22) next to the second side (32) of the vessel (18); moving (540) the lifting device (200) on the vessel (18) between the first guide (100) and the second guide (300); holding (550) the end (11) of the power cable (10) with the lifting device (200) overboard the second side (32) of the vessel (18), thereby allowing the end part (12) of the power cable (10) to be guided from overboard on one side (30) of the vessel (18) to overboard to an opposite side (32) of the vessel (18) and up to the lifting device (200) while working on at least a part of the end part (12) of the power cable (10).14 The method according to claim 13, further comprising moving the second guide (300) towards or away from the first guide (100); and / or further comprising using the second guide (300) to guide a wire (14) connectable to the power cable (10).15 The method according to claim 11, further comprising keeping the end (11) of the power cable (10) on the vessel (18).

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