NO347117B1

NO347117B1 - Marine gangway and a marine structure comprising such a marine gangway

Info

Publication number: NO347117B1
Application number: NO20220055A
Authority: NO
Inventors: Karl Fredrik Sandvik
Original assignee: Ulmatec Handling Systems As
Priority date: 2022-01-17
Filing date: 2022-01-17
Publication date: 2023-05-15
Also published as: WO2023136733A1; NO20220055A1

Description

The present invention is related to a marine gangway and a marine structure comprising such a marine gangway.

BACKGROUND ART AND PROBLEMS RELATED THERETO

Transport of people and goods between a marine structure and a fixed, landbased structure or between two marine structures used to be carried out by lowering a boat on the water and the transport were done on the water. Later, the use of cranes became common and now such transport is often conducted with marine gangways between the structures.

Over the last years the offshore industry, and particularly offshore windmills, has gone through a significant development. Offshore windmills and many other types of marine structures are unmanned and all service personnel and goods must be transported to the site and further transferred to the offshore windmills in a safe and efficient matter. Goods, such as spare parts, also need to be brought to the offshore windmills in a safe manner to avoid any damage to the goods.

Document WO2020009570A1 describes a motion compensated transfer system for transferring persons and/or cargo from a vessel to an offshore object and vice versa. The document discloses a tower with an external lifting unit carrying a platform that together with the lifting unit is adjustable in height along at least a part of said tower, and said tower is provided with a lift and/or staircase housed in a shaft extending in said tower.

Document WO2021191152A1 describes a walk-to-walk system for allowing personnel and/or equipment to move between a vessel and an offshore with turbine.

Document WO 2017135821 A1 describes a height adjustable marine telescopic access bridge, which may be used as a marine gangway attached to a marine structure. The access bridge comprises a tower, and the tower is rotatable around a vertical rotation axis. The tower has at least two openings/doorways for people and/or goods to pass through. A gangway platform is attached to the tower and a gangway is attached to the platform. A lift is arranged inside the tower movably in the longitudinal direction of the tower and adapted to align with the doorways/openings.

The state-of-the-art gangway platforms are installed onboard the marine structure, such as a service boat, fixed in the vertical direction. This means that the gangway will be tilted up or down if the landing point of the platform is not located at the same vertical level as the gangway platform. Since the tide at various sites will raise and lower the vertical level of the deck of the marine structure relative to a fixed structure, it is difficult to arrange the gangway at a horizontal level when it is used. Needless to say, transporting a heavy carriage/wagon on a tilted gangway is neither safe nor efficient.

Furthermore, state-of-the-art gangways rotates about the vertical rotational axis of the support platform which they are connected to, but with limited operational freedom. Such rotational movement about a vertical axis is often controlled by limit switches on the equipment, to ensure that the gangway does not collide with any of the various installations on the marine structure. This limitation in the positioning of the gangway can under certain weather conditions be problematic since the marine structure may have to be located in a given position relative to the offshore windmill. In some locations of the marine structure relative to the offshore windmill the gangway, with its limited movements, may not be able to reach the offshore windmill and when the weather conditions is such that the marine structure has to be in such locations, it is not possible to transfer people or goods from the marine structure to the offshore windmill or vice versa.

Furthermore, the distance and heading between two marine structures where the marine gangway is connected to one of them, may vary during an operation, and it may vary quite rapidly, and sometimes to rapidly for the marine structures to change their headings and/or positions to keep the marine gangway connected. If the heading drops out or the distance for the gangway gets too far, or both, then the operation needs to be aborted and the gangway needs to be decoupled. Aborting such operations is costly and they can be very time consuming.

An object of the present invention was therefore to provide a safe and efficient way of transporting people and goods between a floating marine structure and another fixed or floating structure.

A further object of the present invention was to provide gangway which can be used in a broad variety of weather conditions.

It was also an object of the present invention was to provide a gangway which makes the marine structure less dependent on its position relative to the other fixed or floating structure for a safe and secure connection of the gangway to the fixed or floating structure.

It was also an object of the present invention was to provide a gangway which is capable of a large range of movements without causing damage to other structures on the marine structure it is arranged on.

BRIEF SUMMARY OF THE INVENTION

These objects are achieved with a marine gangway as defined in claim 1 and marine structure as defined in claim 15. Further embodiments of the marine gangway are provided in the dependent claims.

Hence, there is provided a marine gangway which comprises:

a tower which is adapted to be attached to a marine structure, rotatably about a tower rotational axis which extends in a longitudinal direction of the tower, the tower being provided with a tower aperture and at least one tower doorway arranged below and/or above the tower aperture, the tower aperture and the at least one tower doorway being adapted for people and/or goods to pass through,

a gangway device comprising a gangway platform which is attached to the tower movably in the longitudinal direction of the tower, and a gangway which is rotatably attached to the gangway platform,

a lift which is arranged inside the tower movable in the longitudinal direction of the tower, the lift being provided with a lift doorway which is adapted to align with the tower aperture and with the at least one tower doorway as the lift moves in the longitudinal direction of the tower.

It should be noted that the term below should be understood as substantially vertically below in the longitudinal direction of the tower when the marine gangway is installed on a marine structure such a vessel, i.e. vertically below the tower aperture. Similarly, the term above should be understood as substantially vertically above in the longitudinal direction of the tower when the marine gangway is installed on a marine structure such as a vessel, i.e. vertically above the tower aperture.

The fact that you can move the gangway vertically on the tower to align the level of lift door with the gangway platform and minimize the level for the landing point at the approached marine structure, results in a safer and easier passage for people and goods between the marine structures.

Furthermore, the rotatably tower and gangway has two substantially vertical and parallel rotational axes for the gangway operation, a tower rotational axis A for the tower which can be rotated 360 degrees relative to the marine structure, and an attachment platform rotational axis B for the gangway which is usually more limited and may typically be operated within a rotational range of up to 260 degrees relative to the tower. In combination, the rotation of the tower relative to the marine structure it is arranged on and the rotation of the gangway relative to the tower will minimize the shadow areas for the marine gangway operation and allow the gangway to be used in a much wider range of weather conditions.

Since the tower, the lift inside the tower and the gangway device rotate together as a unit about the tower rotational axis, a person and goods can thereby move into and out of the lift through the lift doorway and through the tower aperture or the tower doorway. Furthermore, since the tower aperture can be made fairly long in the longitudinal direction of the tower, there is a good possibility for adjustment of the vertical positioning of the gangway platform so that the gangway can be kept as close as possible to a horizontal level to avoid a sloping gangway, while at the same time the lift can stop at the same vertical level as the gangway platform and people and goods can safely move or be moved from the lift to the gangway platform or vice versa.

A person and goods can thereby move into and out of the lift through the lift doorway and through the tower aperture or the tower doorway. The lift and the doorways are made in such way that goods transport can be brought through on carriages without any obstacles.

The tower doorways can be located on the main deck, or at any other weather deck which is applicable for the installation, and on each applicable deck below the main deck all the way down to the tank top of the marine structure. The tower may be provided with a lift doorway at all the decks of the vessel, and the lift may then stop on each deck, from the tank top up to the tower aperture.

As mentioned above, the tower aperture is preferably elongated and preferably extends in the longitudinal direction of the tower.

In addition, the gangway device is preferably movable in the longitudinal direction of the tower, at least partly along the tower aperture, but preferably along the entire tower aperture. Thereby, the gangway platform can be arranged at a position that allows for a desired slope of the gangway towards the landing point, and ensures safe passage of people and good to the gangway.

The gangway platform may be rollingly and/or slidably attached to the tower. Thereby, the gangway can move along the tower aperture in the longitudinal direction of the tower, i.e. the vertical direction when the marine gangway is installed on a marine structure and in operation, to make it possible for people and goods to move, or be moved, between the lift inside the tower and the gangway platform.

The tower aperture may be provided with a curtain device or any other device that can cover the whole tower aperture or the part of the tower aperture above and/or below the gangway device which, at any time, is exposed to the environment to prevent, or at least reduce, the amount of water in any form (rain, snow, water spray from the sea etc.) to pass through the tower aperture.

The gangway platform preferably comprises a support platform, which is movably attached to the tower in the longitudinal direction of the tower, and an attachment platform, which is rotatably attached to the support platform, where the gangway is rotatably attached to the attachment platform.

The attachment platform is preferably rotatably attached to the support platform about an attachment platform rotational axis which preferably, but not necessarily, is substantially parallel to the tower rotational axis.

The rotational movement of the attachment platform rotational axis can be used to adjust the horizontal direction/angel of the gangway to its landing point on the object that shall be entered.

The gangway is preferably rotatably attached to the attachment platform about an axis C which lie in a plane that is perpendicular, or at least substantially perpendicular, to the attachment platform rotational axis. The rotational movement of the gangway relative to the attachment platform preferably allows

the gangway to pivot up and down relative to a horizontal plane when the marine gangway is in operation and the tower is arranged substantially vertically. Thus, the slope of the gangway can be adjusted to a desired angle and the gangway can be pivoted into a storage position where the gangway is substantially vertically arranged, i.e. substantially parallel to the tower.

The gangway may alternatively be rotatably attached to the attachment platform about two independent axes, C and D, where at least one axis C is perpendicular, or at least substantially perpendicular, to the attachment platform rotational axis. Thus, the gangway be rotatably attached to the attachment platform about two axes, C and D, where the first rotational axis C lie in a plane that is perpendicular, or at least substantially perpendicular, to the attachment platform rotational axis as described above, and the second rotational axis D is substantially perpendicular to the first rotational axis C. Hence, the gangway can be rotated about an axis D in its own longitudinal direction, and therefore, in addition to adjustment of the slope of the gangway from the attachment platform to towards the landing point, the sideways sloping of the gangway can also be adjusted.

The support platform preferably comprises a support platform floor and the attachment platform comprises an attachment platform floor, and the support platform floor and the attachment platform floor are preferably level or at least substantially level. This allows for a safe passage of people and goods between the gangway and the lift in the tower.

The gangway may comprise a first gangway section and a second gangway section, where the second gangway section being telescopically arranged in or on the first gangway section. The gangway may of course also be provided with more than two telescopically arranged gangway sections.

Furthermore, the gangway is preferably rotatable to a stowed position where the gangway extends in the longitudinal direction of the tower, i.e. to a stowed position where the gangway is substantially parallel to the tower.

With a gangway comprising two or more telescopically arranged gangway sections, the longitudinal length can be adjusted to compensate for a variable length from the marine structure, on which the gangway is arranged, to the landing point of the gangway, and the gangway can be arranged in a

substantially vertical storage position, as mentioned above, since the length of the gangway when all the gangway section are retracted, is manageable.

Alternatively, the gangway may also be stowed in a crib arranged on the marine structure on which the gangway is arranged. Thus, the gangway may be stowed in a substantially horizontal position on the deck of the marine structure.

Preferably, the tower and the lift rotate together about the tower rotational axis. Furthermore, the tower and the gangway device preferably rotate together about the tower rotational axis.

The result is that the tower doorway and the tower aperture then is aligned aligned with the lift door in such that it is possible for people to walk and goods to be transported between the lift and the gangway platform and vice versa.

The tower may further be provided with a sail device which is retractable to a storage position and expandable to an active position. The sailing device may be used during a voyage to save fuel. While the gangway device is in operation the sail device can be stowed away in the storage position where the sail device will not interfere with the operation of the gangway device.

The tower is preferably adapted to be mounted to a deck structure of the marine structure with a bearing device, such as a collar bearing or pivot bearing, such that the tower is rotatable about the tower rotational axis. The tower may also be provided with a slewing bearing or any other equivalent solution to turn the tower 360 degrees about the tower rotational axis.

Hence, the tower is preferably adapted to be mounted to the bearing device such that the tower rotational axis is substantially vertical when the deck structure lies in a horizontal plane.

The tower is preferably perpendicular, or at least substantially perpendicular, to the marine structure it is fitted on. It can be mentioned that the longitudinal direction of the tower, i.e. the vertical direction of the tower when the marine gangway is mounted on a marine structure, corresponds to, i.e. is the same as, the direction of the tower rotational axis.

There is also provided a marine structure comprising a marine gangway as defined above including one, some, all or none of the additional features

described herein, where the marine gangway is mounted to the marine structure rotatably relative to the marine structure about the tower rotational axis.

The tower is preferably mounted to a deck of said marine structure with a main bearing such that the tower is rotatable about the tower rotational axis.

The tower is preferably further mounted to the main bearing such that the tower rotational axis is substantially vertical when the deck lies in a horizontal plane. Hence, the rotational axis of the main bearing corresponds to the tower rotational axis, i.e. the rotational axis of the main bearing is identical to or coaxial with the tower rotational axis. The main bearing and tower are then aligned together about the same axis.

The deck of the marine structure, to which the tower is mounted, is preferably the main deck of the marine structure. However, the deck of the marine structure, to which the tower is mounted, may be any other deck of the marine structure with sufficient strength to support the marine gangway including the tower.

The marine structure can be a floating structure, i.e. a structure arranged in a body of water. For example, the marine structure may be one of the following marine structures: a vessel, a ship, a floating platform, a semisubmersible platform, a floating wind power plant or a buoy.

BRIEF FIGURE CAPTIONS

In the following, a non-limiting embodiment of the present invention is shown in various configurations in figures 1-8, and will be described in more detail with reference to said figures, where:

Figures 1a and 1b show respective perspective views of a marine gangway according to the present invention where the tower of the marine gangway has slewed about its own longitudinal axis from a position shown in figure 1a to a position shown in figure 1b.

Figures 2a and 2b show perspective views of the marine gangway shown in figures 1a-1b indicating a rotational movement of the gangway where it is pivoted up and down in a vertical plane.

Figures 3a-3c show perspective views of the marine gangway shown in figures 1-2 where internal travel of the lift inside the tower is indicated.

Figures 4a and 4b show perspective views of the marine gangway shown in figures 1-3 where rotational movement of the attachment platform and the gangway about the rotational axis B is indicated.

Figures 5a and 5b show perspective views of the marine gangway shown in figures 1-4 where rotational movement of the gangway relative to the attachment platform about the rotational axis C is indicated.

Figures 6a and 6b show perspective views of the marine gangway shown in figures 1-5 where the telescopic movement of the second gangway section relative to the first gangway section is indicated.

Figure 7 shows a perspective view of the marine gangway shown in figures 1-6 where the gangway is in the stowed position.

Figures 8a show a perspective view of the marine gangway shown in figures 1-7 including a sail device arranged in a stowed position and where the gangway is in an operating position.

Figures 8b show a perspective view of the marine gangway shown in figures 1-7 including a sail device arranged in a stowed position and where the gangway is also arranged in its stowed position.

Figures 8c show a perspective view of the marine gangway shown in figures 1-7 including a sail device arranged in an active, operating position and where the gangway is arranged in its stowed position.

EMBODIMENTS OF THE INVENTION

Reference is made to figures 1-7 which shows a marine structure 10 comprising a marine gangway 18 according to the present invention. All drawing figures show generally the same embodiment of the marine structure 10, but with that marine gangway 18 arranged in various positions. It should be noted that for the sake of clarity, are not all reference numbers shown in all figures.

The marine gangway 18 comprises a tower 20 which is adapted to be mounted on a marine structure 10, such a vessel, a ship, a floating platform, a semisubmersible platform, a floating wind power plant or a buoy. The tower 20 is rotatably mounted to a main deck 11 of the marine structure 10, preferably, but not necessarily, the main deck 11 with a main bearing 15 that allows the tower 20 to rotate about a tower rotational axis A (see figure 2a). The tower rotational axis A extends in the longitudinal direction of the tower 20 and is substantially vertical when the marine gangway 18 is arranged on the marine structure 10 and the main deck 11 is substantially horizontal.

It should be mentioned that the main bearing 15 of the tower 20 could mounted in another deck of the marine structure 10 which is sufficiently strong to support the tower 20, such as the first lower deck 12 or the second lower deck 13 as indicated on the figures.

The main bearing 15 can be a collar bearing or a pivot bearing which allows the tower 20 to rotate about the tower rotational axis A, preferably 360 degrees about the tower rotational axis A. The tower 20 may also be provided with a slewing bearing or any other equivalent solution to turn the tower 360 degrees about the tower rotational axis A. It should be mentioned that since the tower 20 is rotatably mounted to the marine structure 10, the marine gangway 18 is much more flexible in its use since the marine gangway 18 can now be used in all directions, 360 degrees around the tower rotational axis A as the tower 20 rotates around the tower rotational axis A.

The tower 20 is provided with a lift 28 that runs up and down inside the tower 20. The lift can be adapted to carry any desired number of people and/or any desired goods.

The tower 20 is further provided with a tower aperture 25 and at least one tower doorway 26. The tower doorway 26 or tower doorways 26 corresponds to the lift doorway 29 such that people can enter and exit the lift 28 and goods can be transported in and out of the lift 28 when the lift 28 is arranged adjacent to a tower doorway 26 or the tower aperture 25.

The tower aperture 25 and the tower doorway 26 or tower doorways 26 allow people to enter and exit the lift 28 and goods to be transported in and out of the lift 28 at different vertical levels of the tower 20 and the marine structure 10, for

example through the tower doorway 26 on the second lower deck 13, through the tower doorway 26 on the first lower deck 12 or through the tower aperture 25 above the main deck as indicated on the figures.

The lift 28 is further arranged in the tower 20 such at it rotates together with the tower 20 about the tower rotational axis A. Thus, the lift doorway 29 will always align with the tower aperture 25 and the tower doorway or tower doorways 26 no matter how much the tower 20 is rotated about the tower rotational axis A.

The tower aperture 25 is arranged above the main deck 11 and preferably has an elongated shape as indicated in the figures. The elongated shape of the tower aperture 25 allows the lift 28 to stop at any position between lower most part of the tower aperture 25 to the top most part of the tower aperture 25.

The marine gangway 18 is further provided with a gangway device 32 for transport of people and goods between the marine structure 10 on which the marine gangway 18 is mounted, and an external location (not shown in the figures). The external location can be another marine structure such as a vessel, a ship, a floating platform, a semisubmersible platform, a floating wind power plant or a buoy. The external location can also be a fixed structure such a quay, a pier, an offshore fixed-foundation wind power plant or any other structure arranged in or near the body of water in which the marine structure 10 with the marine gangway 18 is operating.

The gangway device 32 comprises a gangway platform 34. The gangway platform 34 is movably mounted to the tower 20, so that the gangway platform 34 can be moved up and down along the tower 20 in the longitudinal direction of the tower 20. The gangway platform 34 may be rollingly and/or slidably attached to the tower using commonly known roller devices or sliding devices. The marine gangway 18 can thereby move along the tower aperture 25 in the longitudinal direction of the tower 20, which makes it possible for people to move between the lift 28 and the gangway device 32, and goods to be transported between the lift 28 and the gangway device 32, at any desired position along the tower aperture 25 on the tower 20.

The gangway platform 34 preferably comprises a support platform 36 adjacent to the tower 20 as indicated in the figures. The support platform 36 comprises a

support platform floor 37. The support platform floor 37 is preferably plane and substantially horizontal when the tower rotational axis A is substantially vertical.

The gangway platform 34 further comprises an attachment platform 39. The attachment platform 39 is rotatably mounted to the support platform about an attachment platform rotational axis B (see figure 3b). The attachment platform rotational axis B is preferably substantially parallel to the tower rotational axis A.

The attachment platform 39 is provided with an attachment platform floor 40. The attachment platform floor 40 is level, or at least substantially level, with the support platform floor 37 to facilitate easy and secure transport of goods across the gangway platform 34 and to make it safe for people to walk across the gangway platform 34.

The gangway device 32 further comprises a gangway 42. The gangway 42 is rotatably attached to the attachment platform 39 about at least one rotational axis C, D. The gangway 42 is provided with a transport floor 43 on which people can walk and goods can be transported. The gangway 42 is preferably preferably arranged so that the transport surface 43 is level with, or at least substantially level with, the attachment platform floor 40 and the support platform floor 37 when the gangway 42 is arranged in a position where the gangway floor 43 is substantially horizontal. That will ensure that it is safe and secure for people to walk from the lift 28, across the gangway platform 34 and to the gangway floor 43, and that goods can be securely transported across the gangway platform 34 and to the gangway floor 43.

It should also be mentioned that the elongated shape of the tower aperture 25 allows the gangway platform 34 to be positioned at any position along the length of the tower aperture 25 allowing the level of the transport floor 43 of the gangway 42 to be adjusted so that the slope of the gangway 42 between the gangway platform 34 and the external location that the gangway is landed on, can be adjusted and reduced to a desired slope. A desired slope may be substantially horizontal, or as close as possible to horizontal, or if heavy goods are being transported across the gangway 42, possibly so that the gangway has a slight downward slope in the direction that the goods will be transported.

As mentioned above, the attachment platform 39 is rotatable about the attachment platform rotational axis B. This rotational movement of the

attachment platform 39 allows the gangway 42 to turn sideways relative to the support platform 36 as indicated in figures 4a and 4b where the gangway 42 is shown in two different positions relative to the support platform 36.

The gangway 42 is preferably at least rotatable about a first gangway rotational axis C (see figure 3b) allowing the gangway to pivot up and down about the first gangway rotational axis C as indicated in figure 5a, where the gangway 42 is pivoted downwards relative to the attachment platform 39 about the first gangway rotational axis C, and in figure 5b, where the gangway 42 is pivoted upwards relative to the attachment platform 39 about the first gangway rotational axis C.

The gangway 42 may also be rotatable about a second gangway rotational axis D (see figure 3b) allowing the gangway 42 to rotate or pivot about the second gangway rotational axis D. The second gangway rotational axis D extends in the longitudinal direction of the gangway 42, preferably centrally along the gangway 42, so that the gangway 42 turns about itself in the longitudinal direction of the gangway 42.

The gangway 42 preferably comprises a telescopic structure as indicated in the figures, in order to extend the reach of the gangway 42 and to provide the gangway 42 with a variable length so that the length of the gangway 42 can be adapted to a variety of distances between the marine structure 10 and an external location to which the gangway 42 is to connect the marine structure 10.

Thus, the gangway may comprise at least a first gangway section 44, which is rotatably attached to the attachment platform 39, and a second gangway section 45, which is telescopically arranged in or on or to the first gangway section 44. As indicated in figure 6b, the second gangway section 45 can be retracted to a inner position where the length of the gangway 42 is the same as the length of the first gangway section 44. The second gangway section 45 can further be extended telescopically from the first gangway section 44 to a fully extended position as indicated in figure 6a, and to any desired intermediate position between the stowed position and the fully extended position so that the length of the gangway 42 is variable and can be adapted as is necessary.

It should be noted that if it is deemed to be necessary or desirable, the gangway 42 may also comprise three or more telescopically arranged gangway sections.

Although not shown in the figures, the gangway platform 32, i.e. the support platform 36 and the attachment platform 39, are preferably provided with the necessary railings for safety for people and goods crossing the gangway platform 34.

In figure 7 the gangway 42 is shown in its stowed position or storage position, i.e. the position in which the gangway 42 is arranged when it is not in use.

In the stowed position, the gangway platform 34 is preferably moved to its lower most position on the tower 20, the telescopic sections of the gangway 42, i.e. the second gangway section 45 in the figures, are preferably fully retracted and the gangway 42 is rotated upwards until it is substantially vertical, i.e. substantially parallel with the tower 20 as indicated in figure 7. As mentioned, the gangway 42 can be arranged in the stowed position when it is not in use, for example when the marine structure 10, on which the marine gangway 18 is mounted, is travelling between two locations. It should be mentioned that a stowed position like this, and as shown in figure 7, saves a lot of space on the main deck 11 of the marine structure 10 and the gangway 42 is much less in the way for other operations that may take place on the main deck 11 than if the gangway 42 is stored horizontally in a crib on the main deck 11.

As described above, the marine gangway 18 is designed to be very flexible in its use. The tower 20 is provided with a lift 28 travelling up and down inside the tower 20 to any desired level, one or more tower doorways 26 allowing access to the lift from one or more decks on the marine structure 10, a tower aperture with an elongated shape which provides flexibility of the positioning of the gangway platform 34 so that a desired slope of the gangway floor 43 can be obtained. Furthermore, since the gangway 42 is mounted on the attachment platform 39, which can be rotated about the attachment platform rotational axis B relative to the support platform 36, the gangway 42 can be moved sideways relative to a vertical direction. In addition, the gangway 42 may comprise two or more gangway sections 44, 45 such that the length of the gangway 42 can be adjusted. The result is that the marine gangway 18 according to the present invention is very flexible when it comes to landing the gangway on an external location, such as an offshore wind mill.

Furthermore, the marine gangway 18 may be provided with sensors that register the position of the tower 20 relative to the marine structure 10, i.e. the rotational

position of the tower 20 about the tower rotational axis A, the position of the support platform 36 relative to the tower 20, the position of the attachment platform 39 relative to the support platform 36, i.e. the rotational position of the attachment platform 39 about the attachment platform rotational axis B, the position of the gangway 42 relative to the attachment platform 39, i.e. the rotational position of the gangway 42 about the first gangway rotational axis C and/or about the second gangway rotational axis D, and the extension of the telescopic gangway section or sections 45, i.e. the total length of the gangway 42. The marine gangway 18 may further be provided with a control system which is signally connected to said sensors and which controls and adjusts said positions of the tower 20, support platform 36, attachment platform 39, gangway 42 and the length of the gangway 42 such that the outer end portion of the gangway is kept at a desired position when the marine structure 10 moves, for example due to wave motions in the sea.

In figures 8a-8c there is shown a variant of the marine gangway shown in figures 1-7 comprising a sail device 48. The sail device 48 comprises a sail 49 which can be extended to an active position, as shown in figure 8c, and retracted or pulled back into an inactive position as shown in figures 8a and 8b.

The sail device 48 may further comprise a sail expanding element 51 and at least one, but preferably two attachment elements 50 which are attached to the tower 20 of the marine gangway 18. The attachment elements 50 preferably comprise means for storing the sail 49, for example by rolling the sail on and off a cylindrical core element (not shown in the figures). The sail device 48 preferably further comprises at least one expanding device (not shown in the figures) which is capable of moving the expanding element 51 between the active position and the inactive position of the sail 49. The expanding device may, for example, comprise a piston/cylinder arrangement.

The sail 49 may be made of a canvas material or any other suitable material that is strong enough to function as a sail, and preferably which can be rolled up when the sail 49 is in the inactive position.

When the marine structure 10 is travelling between two locations, the gangway can be arranged in its stowed position as shown in figures 8a-8c, and the tower 20 can be rotated about the tower rotational axis A as indicated by arrow V.

Thus, the position of the sail 49 can adjusted to account for the wind direction to make sure that the maximum efficiency obtain.

It should be noted that the only difference between the marine gangway 18 shown in figures 8a-c and the marine gangway 18 shown in figure 1-7 is the sail device 49 that the marine gangway 18 shown in figures 8a-c is provided with. Thus, all the description of the marine structure shown in figures 1-7 is also valid for the marine structure shown in figures 8a-c.

Claims

1. A marine gangway (18), comprising:

a tower (20) which is adapted to be attached to a marine structure (10), rotatably about a tower rotational axis (A) which extends in a longitudinal direction of the tower (20), the tower (20) being provided with a tower aperture (25) and at least one tower doorway (26) arranged below and/or above the tower aperture (25), the tower aperture (25) and the at least one tower doorway (26) being adapted for people and/or goods to pass through, c h a r a c t e r i z e d b y;

a gangway device (32) comprising a gangway platform (34) which is attached to the tower (20) movably in the longitudinal direction of the tower (20), and a gangway (42) which is rotatably attached to the gangway platform (34),

a lift (28) which is arranged inside the tower (20) movable in the longitudinal direction of the tower (20), the lift (28) being provided with a lift doorway (29) which is adapted to align with the tower aperture (25) and with the at least one tower doorway (26) as the lift (28) moves in the longitudinal direction of the tower (20).

2. The marine gangway according to claim 1,

wherein the gangway platform (34) comprises a support platform (36), which is movably attached to the tower (20) in the longitudinal direction of the tower (20), and an attachment platform (39), which is rotatably attached to the support platform (36), and wherein the gangway (42) is rotatably attached to the attachment platform (39).

3. The marine gangway according to claim 2,

wherein the attachment platform (39) is rotatably attached to the support platform (36) about an attachment platform rotational axis (B) which is substantially parallel to the tower rotational axis (A).

4. The marine gangway according to claim 2 or 3,

wherein the gangway (42) is rotatably attached to the attachment platform (39) about an axis (C or D) which lie in a plane that is substantially perpendicular to the attachment platform rotational axis (B).

5. The marine gangway according to claim 2 or 3,

wherein the gangway (42) is rotatably attached to the attachment platform (39) about two independent axes (C, D), of which at least one axis (C) lie in a plane that is substantially perpendicular to the attachment platform rotational axis (B).

6. The marine gangway according to one of the claims 2-5,

wherein the support platform (36) comprises a support platform floor (37) and the attachment platform (39) comprises an attachment platform floor (40), the support platform floor (37) and the attachment platform floor (40) being level or at least substantially level.

7. The marine gangway according to one of the claims 1-6,

wherein the tower aperture (25) is elongated and extends in the longitudinal direction of the tower (20).

8. The marine gangway according to one of the claims 1-7,

wherein the gangway device (32) is movable in the longitudinal direction of the tower (20) at least partly along the tower aperture (25).

9. The marine gangway according to one of the claims 1-8,

wherein the gangway (42) comprises a first gangway section (44) and a second gangway section (45), the second gangway section (45) being telescopically arranged in or on the first gangway section (44).

10. The marine gangway according to one of the claims 1-9,

wherein the gangway (42) is rotatable to a stowed position where the gangway (42) extends in the longitudinal direction of the tower (20).

11. The marine gangway according to one of the claims 1-10,

wherein the gangway platform (34) is rollingly and/or slidably attached to the tower (20).

12. The marine gangway according to one of the claims 1-11,

wherein the tower (20) and the lift (28) rotate together about the tower rotational axis (A).

13. The marine gangway according to one of the claims 1-12,

wherein tower (20) and the gangway device (32) rotate together about the tower rotational axis (A).

14. The marine gangway according to one of the claims 1-13,

wherein tower (20) is provided with a sail device (48) which is retractable to a storage position and expandable to an active position.

15. A marine structure (10) comprising a marine gangway (18) according to any one of the claims 1-14, where the marine gangway (18) is mounted to the marine structure (10) rotatably relative to the marine structure (10) about the tower rotational axis (A).

16. The marine structure according to claim 15,

wherein the tower (20) is mounted to a deck (11, 12, 13) of said marine structure (10) with a main bearing (15) such that the tower (20) is rotatable about the tower rotational axis (A).

17. The marine structure according to claim 16,

wherein the tower (20) is mounted to the main bearing (15) such that the tower rotational axis (A) is vertical, or at least substantially vertical, when the deck (11, 12, 13) lies in a horizontal plane.

18. The marine structure according to claim 16 or 17,

wherein said deck of the marine structure (10) is the main deck (11) of the marine structure (10).

19. The marine structure according to one of the claims 15-18,

wherein the marine structure (10) is a floating structure.

20. The marine structure according to one of the claims 15-19,

wherein the marine structure (10) is one of the following marine structures: a vessel, a ship, a floating platform, a semisubmersible platform, a floating wind power plant, a buoy.