The present invention is related to a mooring device for mooring of a floating unit to a floating or non-floating structure and a floating unit and a non-floating structure comprising one or more such mooring devices.
Floating units of various types such as semi-submersible units, ships, barges and other types of floating unit, for various reasons, at times usually need to be moored to a floating structure, such as a semi-submersible unit, a ship, a barge or other types of floating vessels, or to a non-floating structure, such as a quay, a pier or similar non-floating structure that the floating unit can be moored to.
Transfer of temperate fluids from ship to shore is today achieved, among other methods, through a submerged flexible hose, which is lifted from the seabed and connected directly to the vessel manifold.
The handling of pipes for cryogenic applications will, however, often be difficult for the ship's lifting equipment and manifold since the transfer of cryogenic fluids through the pipes will cause accumulation of an external ice layer. The transfer of cryogenic liquids through any pipe in contact with water therefore requires the pipe to be extensively insulated, resulting in considerably larger weight per meter than pipes for transfer of temperate fluids. The insulation is also required to avoid excessive heat loss.
The use of loading systems comprising various types of floating concepts are known in the offshore petroleum industry. Environmental conditions offshore are often harsh, which significantly increases the requirements and cost for systems to operate in these conditions.
A few mooring devices, other than traditional ropes, wires or the like, are known in the art. For example, to overcome at least some of the problems of the prior art, a floating unit for transfer of a fluid or electric power between a floating structure and a floating or non-floating structure has been proposed and described in the publication WO 2015/107147 A1. There is, however, a need for further improvement of the mooring system that is disclosed in this publication that can be used to moor a floating unit to a floating or non-floating structure.
Other known mooring systems are disclosed in the publications US 2004/154518 A1 and WO 2009/048342 A2.
An objective of the present invention has therefore been to provide a mooring device for mooring a floating unit to a floating or non-floating structure that allows vertical translational motion and rotational motion about any horizontal axis of the floating unit relative to the floating or non-floating structure while lateral translational motion and rotational motion about a vertical axis of the floating unit relative to the floating or non-floating structure is substantially restricted.
Another objective of the present invention has been to optimize the transfer of loads through the mooring device where the loads are caused by relative motions between a floating unit and a floating or non-floating structure when the floating unit is moored to the floating or non-floating structure with one or more mooring devices according to the present invention.
Another objective has been to make it possible to obtain a close mooring distance between a floating unit and a floating or non-floating structure also when there is a large freeboard difference between the floating unit and the floating or non-floating unit.
Another objective has been to obtain a mooring device that provides a robust and reliable connection between the floating unit and the floating or non-floating structure to which the floating unit is moored.
Another objective has been to obtain a mooring device with low manufacturing and installation costs and low maintenance costs.
These objectives are achieved by a mooring frame as defined in claim 1, a floating structure as defined in claim 21, a non-floating structure as defined in claim 22, and use of the mooring frame as defined in claims 29 and 30. The independent claims define further embodiments of mooring frame and the floating structure.
The mooring device disclosed herein can be used to temporarily moor a floating unit, such as a vessel or a platform, to another floating or non-floating unit, vessel or structure. The mooring device absorbs forces and energy that arise from relative motions between the floating unit and the floating or non-floating structure. The forces and energy that arises from relative motions taking place in two main directions in a horizontal plane, a first direction and a second direction, which are typically the x-direction and y-direction in a Cartesian coordinate system, are absorbed by the mooring device.
Typically, two mooring devices may be used to moor the floating unit which are connected to the floating unit or to the floating or non-floating unit, vessel or structure with a joint that allows rotational motion about three independent axes, for example universal joints. The frames are provided with vacuum pads or electromagnetic pads for temporary mooring of the floating unit to the floating or non-floating unit or vessel and thereby transferring loads that arise from the relative motion. The mooring devices may be provided with mooring units and support elements that absorb energy from relative translational motion in the horizontal plane by using integrated stiffness elements, for example spring elements. Damping elements may also be included if that is required.
There is disclosed a mooring device for mooring of a floating unit to a structure where the structure is floating or non-floating. The mooring device is adapted to be mounted on the structure and the mooring device comprises:
a first mooring arm for transferring and/or absorbing forces and energy that arises when the floating unit is moored to the structure and the floating unit moves relative to the structure, the first mooring arm having a longitudinal axis,
a second mooring arm for transferring and/or absorbing forces and energy that arises when the floating unit is moored to the structure and the floating unit moves relative to the structure, the second mooring arm having a longitudinal axis,
a joint device comprising a support element, a support element joint device and an attachment unit joint device, the support element joint device being connected to the support element and the attachment unit joint device being attached to or connected to the support element,
an attachment unit that is attached to the attachment unit joint device, the attachment unit joint device allowing rotation of the attachment unit about two or three independent axes of rotation relative to the support element, wherein
the support element joint device comprises a first mooring arm joint device connected to or attached to the support element and a second mooring arm joint member connected to or attached to the support element,
the first mooring arm comprises a first end portion and a second end portion, the second end portion being adapted for attachment to the floating unit or the structure, and the first end portion being attached to the first mooring arm joint device,
the second mooring arm comprises a first end portion and a second end portion, the second end portion being adapted for attachment to the floating unit or the structure, and the first end portion being attached to the second mooring arm joint device,
the support element joint device allows rotation of the support element about one rotational axis A only, relative to the first mooring arm and/or the second mooring arm in all positions of the axis A, the rotational axis A being perpendicular to a plane that is formed by the longitudinal axis of the first mooring arm and the longitudinal axis of the second mooring arm in all positions of the first mooring arm and the second mooring arm.
The second mooring arm joint device may allow rotation of the second mooring arm about zero, one or two or three independent axes of rotation relative to the support element.
The first mooring arm joint device may allow rotation of the first mooring arm about one or two or three independent axes of rotation relative to the support element.
The first mooring arm is telescopic and comprises first telescopic part comprising the first end portion of the first mooring arm, and a second telescopic part comprising the second end portion of the first mooring arm.
The second mooring arm is preferably telescopic and comprises first telescopic part comprising the first end portion of the second mooring arm, and a second telescopic part with the second end portion of the second mooring arm.
The first mooring arm may comprise a first double-acting, hydraulic cylinder and that the second arm comprises a second double-acting, hydraulic cylinder.
The first double-acting hydraulic cylinder and the second double-acting hydraulic cylinder are preferably passive hydraulic cylinders.
The first mooring arm joint device of the support element joint device or the second mooring arm joint device of the support element joint device is preferably securely attached to the support element.
The support element preferably comprises a base plate element, a first side plate element that is securely attached to the base plate element and a second side plate element that is securely attached to the base plate element, the first mooring arm and the second mooring arm being rotatably connected to the first side plate element and the second side plate element.
The support element joint device further preferably comprises a bolt element that goes through the first mooring arm joint device, the second mooring arm joint device, the first side plate element and the second side plate element such that the first mooring arm and the second mooring arm are rotatably connected to the support element about a longitudinal axis A of the bolt element.
In an embodiment, the first mooring arm joint device may be fork-shaped, the second mooring arm joint device is plate-shaped and adapted to fit into the fork-shaped first mooring arm joint device, the support element may be fork-shaped and the fork-shaped first mooring arm joint device may be adapted to fit into the fork-shaped support element, such that the bolt element goes through the first mooring arm joint device, the second mooring arm joint device, the first side plate element and the second side plate element.
The fork-shaped first mooring arm joint device may be securely attached to the support element, i.e. the first side plate element and/or the second side plate element.
The second end portion of the first mooring arm may be attached to a first attachment joint device that is adapted for attachment to the floating unit or the structure and allows rotation of the first mooring arm about three independent axes relative to the floating unit or the structure.
The second end portion of the second mooring arm may be attached to a second attachment joint device that is adapted for attachment to the floating unit or the structure and allows rotation of the second mooring arm about three independent axes relative to the floating unit or the structure.
This arrangement allows each of the first and second mooring arms to rotate about two different axes—about the axis A that is perpendicular to the plane formed by the longitudinal axes of the first and second mooring arms as defined above and about a second axis that passes through the first and second attachment joint devices respectively. When the arms are moving sideways, i.e. the first and second mooring arms move in a plane that is perpendicular to axis A, the axis A will be parallel to the rotational axes passing through the first and second attachment joint devices.
In an embodiment, the support element may comprise a plate element to which the first mooring arm joint device and the second mooring arm joint device are securely attached, the first mooring arm joint device and the second mooring arm joint device allowing rotation of the first mooring arm and the second mooring arm respectively about three independent axes of rotation.
The first mooring arm joint device and the second mooring arm joint device are preferably ball joints and/or universal joints.
The support element joint device preferably further comprises a restricting arm comprising a first end portion and a second end portion, the second end portion being adapted for attachment to the floating unit or the structure, and the first end portion being securely attached to the support element.
The restricting arm is preferably telescopic comprising a first telescopic part comprising the first end portion of the restricting arm, and a second telescopic part comprising the second end portion of the restricting arm.
The second end portion of the restricting arm is attached to an attachment joint device that is adapted for attachment to the floating unit or the structure and allows rotation of the restricting arm about two independent axes relative to the floating unit or the structure. The attachment joint device may for example be a cardan joint.
The restricting arm may be provided with a polygonally shaped cross-section such that rotation of the support element about a longitudinal axis of the restricting arm is prevented.
The first end portion of the restricting arm may be securely attached to the support element by welding or with at least one bolt element.
In an embodiment, the support element may comprise a holder element, a first pin element that is securely attached to the holder element and a second pin element that is securely attached to the holder element, the first mooring arm and the second mooring arm being rotatably connected to the first pin element and the second pin element respectively about an axis A that passes through the first pin element and the second pin element.
The fork-shaped first mooring arm joint device may be securely attached to the support element, for example to the holder element of the support element and/or to the first and/or second pin element of the support element. Alternatively, the fork-shaped second mooring arm joint device may be securely attached to the support element, for example to the holder element of the support element and/or to the first and/or second pin element of the support element.
The first mooring arm joint device may be fork-shaped and adapted to be rotatably connected to the first pin element and the second pin element of the holder element, and the second mooring arm joint device may be fork-shaped and adapted to be rotatably connected to the first pin element and the second pin element of the holder element.
The first pin element may be attached to a first side face of the holder element and the second pin element may be attached to a first side face of the holder element, where the first side face and the second side face are opposite exterior sides of the holder element.
The mooring device further may comprise a support arm comprising a first end portion to which a first attachment joint device is attached that is attached to the support element, and a second end portion to which a second attachment joint device is attached that is adapted for attachment to the floating unit or the structure, the first attachment joint device allowing rotation of the support arm about three independent axes relative to the support element and the second attachment joint device allowing rotation of the support arm about three independent axes relative to the floating unit or the structure.
Instead of one support arm for every mooring device, a support arm for every mooring arm may also be used.
The support arm is preferably telescopic and comprises a first telescopic part comprising the first end portion of the support arm and a second telescopic part comprising the second end portion of the support arm.
The attachment unit joint device may comprise a ball element that is securely attached to the support element and a ball support element that is securely attached to the attachment unit.
The attachment unit joint device may comprise a ball element that is securely attached to the attachment unit and a ball support element that is securely attached to the support element of the joint device.
The attachment unit preferably comprises a frame device to which at least one attachment member is rotatably attached and to which the attachment unit joint device is attached.
The at least one attachment member preferably comprises a vacuum pad or an electromagnetic pad.
A floating unit is also provided comprising at least one mooring device as described above, wherein the at least one mooring device is attached to the floating unit for mooring of the floating unit to a structure, the structure being floating or non-floating.
A non-floating structure is also provided comprising at least one mooring device as described above, wherein the at least one mooring device is attached to the non-floating structure for mooring of a floating unit to the non-floating structure.
The floating unit or the non-floating structure to which the at least one mooring device is attached, may comprise at least one fender device to prevent or cushion impacts against the at least one mooring device.
The at least one fender device is preferably compressible in a direction towards the floating unit or the non-floating structure.
The at least one fender device, in an uncompressed state, preferably extends further out from the floating unit or the non-floating structure than the at least one mooring device when mooring device is fully retracted.
The at least one fender device, in a compressed state, preferably extends substantially equally far out from the floating unit or the non-floating structure as the at least one mooring device when mooring device is fully retracted.
The floating unit or the non-floating structure may comprise one or a plurality of mooring devices and at least one fender device mounted to the floating unit or the non-floating structure, on either side of the mooring device or mooring devices.
The mooring device may be mounted on a floating unit, centrally along a side of floating unit.
A use of the mooring device as described above would be for mooring of a floating unit to a floating or non-floating structure, wherein the mooring device is attached to the floating unit.
A further use of the mooring device as described above would be for mooring of a floating unit to a floating structure or a non-floating structure, wherein the mooring device is attached to the floating structure or the non-floating structure. This means that instead of mounting the mooring device to the floating unit, the mooring unit is mounted on the floating or non-floating structure that the floating unit is moored to, for example a ship, a pier or any other type of floating or non-floating structure to which a floating unit may be moored.
In the following, some non-limiting embodiments of the present invention will be described in more detail, with reference to the figures where:
The figures show three different embodiments of a mooring device 10 according to the present invention and two variants of one of the embodiments. The mooring device 10 comprises a joint device 28 that can be designed in different ways, and the three embodiments shown in the figures illustrate three different embodiments of the joint device 28 with two variants of one of the variants. It should be noted that the same features of the different embodiments of the invention shown in the figures have been provided with the same reference numbers.
To the second end portion 16 of the first mooring arm 12, a first attachment joint device 17 is securely attached, for example with one or more bolt elements, by welding or any other suitable fastening method. The first attachment joint device 17 is adapted to be securely attached to a floating unit 110 or a floating or non-floating structure 125, for example by bolts, welding or any other suitable fastening means or methods for fastening the first attachment joint device 17. The first attachment joint device 17 preferably allows the first mooring arm 12 to rotate about three independent axes relative to a floating unit 110 or the floating or non-floating structure 125 that the mooring device 10 is attached to. For example, the first attachment joint device 17 may be a ball joint or a universal joint but may also be any other joint device that allows movement of the first mooring arm 12 about three independent axes relative to the floating unit 110 or the floating or non-floating structure 125 that the mooring device 10 is attached to.
The first mooring arm 12 is preferably telescopic as is shown in for example
As indicated in
The first attachment joint device 17 is therefore preferably attached to the second telescopic part 14 of the first mooring arm 12 and adapted for attachment to a floating unit 110 or a floating or non-floating structure 125.
To the second end portion 24 of the second mooring device 20, a second attachment joint device 25 is securely attached, for example with one or more bolt elements, with welding or any other suitable fastening method. The second attachment joint device 25 is adapted to be securely attached to a floating unit 110 or a floating or non-floating unit 125, for example by bolts, welding or any other suitable fastening means or methods for fastening the second attachment joint device 25. The second attachment joint device 25 preferably allows the second mooring arm 20 to rotate about three independent axes relative to a floating unit 110 or the floating or non-floating structure 125 that the mooring device 10 is attached to. For example, the second attachment joint device 25 may be a ball joint or a universal joint but may also be any other joint device that allows movement of the second mooring arm 20 about three independent axes relative to the floating unit 110 or the floating or non-floating structure 125 that the mooring device 10 is attached to.
The second mooring arm 20 is preferably telescopic as is shown in for example
As shown clearly in
The second attachment joint device 25 is therefore preferably attached to the second telescopic part 22 of the second mooring arm 20 and adapted for attachment to a floating unit 110 or a floating or non-floating structure 125.
The mooring device 10 further comprises an attachment unit 66 that is attached to the joint device 28 of the mooring device 10.
The attachment unit 66 comprises a frame device 67 and at least one, but preferably a plurality of attachment members 85, 87, 89, 91 that are independently attached to the frame device 67 with respective joint devices that allows the attachment members 85, 87, 89, 91 to rotate about one, two or three independent axes relative to the frame device 67. The joint devices may for example be a bolt element, a cardan joint, a ball joint, a universal joint or any other joint device that will allow the attachment members 85, 87, 89, 91 to move independently about the desired number of independent axes. Vulcanized vacuum pads may also be used which are fairly free to move but is almost completely locked in their positions.
The frame device 67 may obviously be designed in many different ways. One example is shown in
The first frame member 68 comprises a first end portion 69 where a first joint device 70 is arranged or mounted. The first attachment member 85 is connected to the first joint device 70 such that the first attachment member 85 is rotatably attached to the frame device 67. The first joint device 70 shown is a bolt element which will allow the first attachment member 85 to rotate about one axis relative to the frame device 67. However, other types of joint devices may also be employed to connect the first attachment member 85 to the first end portion 69 that will allow the first attachment member 85 to rotate about one, two or three axes relative to the first end portion 69 and the frame device 67 as mentioned above.
The first frame member 68 further comprises a second end portion 71 where a second joint device 72 is arranged or mounted. The fourth attachment member 91 is connected to the second joint device 72 such that the fourth attachment member 91 is rotatably attached to the frame device 67. The second joint device 72 shown is a bolt element which will allow the fourth attachment member 91 to rotate about one axis relative to the frame device 67. However, other types of joint devices may also be employed to connect the fourth attachment member 91 to the second end portion 71 that will allow the fourth attachment member 91 to rotate about one, two or three axes relative to the second end portion 71 and the frame device 67 as mentioned above.
The second frame member 74 comprises a first end portion 75 where a third joint device 76 is arranged or mounted. The second attachment member 87 is connected to the third joint device 76 such that the second attachment member 87 is rotatably attached to the frame device 67. The third joint device 76 shown is a bolt element which will allow the second attachment member 87 to rotate about one axis relative to the frame device 67. However, other types of joint devices may also be employed to connect the second attachment member 87 to the first end portion 75 that will allow the second attachment member 87 to rotate about one, two or three axes relative to the first end portion 75 and the frame device 67 as mentioned above.
The second frame member 74 further comprises a second end portion 77 where a fourth joint device 78 is arranged or mounted. The third attachment member 89 is connected to the fourth joint device 78 such that the third attachment member 89 is rotatably attached to the frame device 67. The fourth joint device 78 shown is a bolt element which will allow the third attachment member 89 to rotate about one axis relative to the frame device 67. However, other types of joint devices may also be employed to connect the third attachment member 89 to the second end portion 77 that will allow the third attachment member 89 to rotate about one, two or three axes relative to the second end portion 77 and the frame device 67 as mentioned above.
By choosing other types of joint devices, the attachment members 85, 87, 89, 91 may therefore be made to be rotatable about two or three independent axes relative to the frame device 67 instead of one axis as shown in
As an alternative to what is mentioned above, the attachment members 85, 87, 89, 91 may be provided with respective spherical joints which are mounted to the bolt elements 70, 72, 76, 78. This arrangement will allow the attachment members 85, 87, 89, 91 to move in three degrees of freedom.
As shown in
It should, however, be mentioned that the attachment unit 66 may be provided with any suitable and desirable number of attachment members other than four as shown in
As shown in
The frame device 67 may further comprise, as shown in
The first, second, third and fourth attachment members 85, 87, 89, 91 are preferably vacuum pads or electromagnetic pads that can be attached to an outer surface of a floating unit 110 or a floating or non-floating structure 125, for example to the outer surface of the hull of an LNG-carrier, and later be detached from said outer surface. Such vacuum pads and electro-magnetic pads are well known in the art and will not be described in any further detail here.
It should also be mentioned that the attachment unit 66 described above and shown in
The mooring device 10 comprises a joint device 28 as mentioned above. The joint device 28 comprises three main parts, a support element 30, an attachment unit joint device 61 that is attached or connected to the support element 30 and a support element joint device 43 that is attached or connected to the support element 30. The joint device 28 is what separates the three embodiments of the mooring device 10 shown in the figures from each other, and the three different designs of the joint device 28 will be described in connection with the description of each embodiment.
The joint device 28 of the first embodiment of the mooring device 10 shown in
The joint device 28 of the first embodiment of the mooring device 10 further comprises a support element joint device 43 comprising a first mooring arm joint device 44 and a second mooring arm joint device 45.
The first mooring arm joint device 44 is securely attached to the first end portion 15 of the first mooring arm 12, for example by welding or by one or more bolts. The second mooring arm joint device 45 is securely attached to the second mooring arm 20, for example by welding or by one or more bolts.
The first mooring arm joint device 44 may have a generally U-shape or fork-shape as indicated in
The support element joint device 43 further comprises a bolt element 46 that goes through or passes through corresponding holes in the first side plate element 33 and the second side plate element 34 of the fork-shaped support element 30, the fork-shaped first mooring arm joint device 44 of the support element joint device 43 and the second mooring arm joint device 45 of the support element joint device 43.
This allows a configuration where both the first mooring arm 12 and the second mooring arm 20 are rotatably connected to the support element joint device 43, i.e. the first mooring arm 12 and the second mooring arm 20 are both rotatable about an axis A that passes through the bolt element 46. The axis A is indicated on
However, it may be advantageous if only one of the first mooring arm joint device 44 and the second mooring arm joint device 45 is allowed to rotate relative to the support element 30, since this will allow the movements and the position of the attachment unit 66 to be tracked and controlled.
The first mooring arm joint device 44 may therefore, preferably, be securely attached to the support element 30, for example by welding or by bolting or any other suitable method of securely attaching the first mooring arm joint device 44 to the support element 30. On the other hand, the second mooring arm joint device 45 is preferably rotatably connected to the bolt element 46, i.e. the second mooring arm joint device 45 is rotatable relative to the support element 30 about the axis A passing through the bolt element 46. Alternatively, it would obviously be possible to securely attach the second mooring arm joint device 45 to the support element 30, for example by welding bolting or any other suitable fastening method, while the first mooring arm joint device 44 is connected to the support element rotatable relative to the support element 30 about the axis A passing through the bolt element 46.
This configuration with the plate and fork-shaped first mooring arm joint device 44 and plate-shaped second mooring arm joint device 45 that fits into the fork of the first mooring arm joint device 44, ensures that the one of the first mooring arm joint device 44 and the second mooring arm joint device 45 that is rotatable relative to the support element 30, can only rotate about the axis A passing through the bolt element 46.
The support element joint device 43 thereby allows the support element 30 to rotate about one axis only which is perpendicular to a plane formed by the longitudinal axis of the first mooring arm and the longitudinal axis of the second mooring arm, where the axis A passes through the bolt element 46 as indicated in
The joint device 28 of the first embodiment of the mooring device 10 further comprises an attachment unit joint device 61 for attachment of the joint device 28 to the attachment unit 66. The attachment unit joint device 61 may be a cardan joint, allowing the attachment unit 66 to rotate about two independent axes relative to the support element 30. Alternatively, as shown in
The joint device 28 of the second embodiment of the mooring device 10 shown in
The joint device 28 of the second embodiment of the mooring device 10 further comprises a support element joint device 43 comprising first mooring arm joint device 48 and a second mooring arm joint device 49. The first mooring arm joint device 48 and the second mooring arm joint device 49 are securely attached to the plate element 36 of the support element 30, for example by welding, by bolting or by any other suitable fastening means.
The first mooring arm joint device 48 preferably allows the first mooring arm 12 to rotate about three different axes of rotation relative to the support element 30. The first mooring arm joint device 48 may for example be a ball joint where the ball element is securely attached to the first end portion 15 of the first mooring arm 12 and the ball support element is securely attached to the plate element 36 of the support element 30 as indicated on
The second mooring arm joint device 49 preferably allows the second mooring ai n 20 to rotate about three different axes of rotation relative to the support element 30. The second mooring arm joint device 49 may for example be a ball joint where the ball element is securely attached to the first end portion 23 of the second mooring arm 20 and the ball support element is securely attached to the plate element 36 of the support element 30 as indicated in
The support element joint device 43 further comprises a restricting arm 51, i.e. a movement restricting arm 51 that restricts the movements of the support element 30.
The restricting arm 51 comprises a first end portion 54 and a second end portion 53. The first end portion 54 is securely attached to the support element 30 of the joint device 28, for example by welding, as indicated in
The restricting arm 51 is preferably telescopic as is shown in
The cross-section A-A of the restricting arm 51, as indicated in
The attachment joint device 56 may be a cardan joint as indicated in
This configuration of the joint device 28 of the second embodiment of the mooring device 10, where the restricting arm 51 is securely attached to the plate element of the support element 30 and to the floating unit 110 with a cardan joint 56 and the first mooring arm 12 and the second mooring arm 20 are attached to the support element with ball joints 48 and 49, ensures that the support element joint device 43 allows rotation of the support element 30 about one axis only, i.e. about the axis A which will always be perpendicular to the plane formed by the longitudinal axes of the first mooring arm 12 and the second mooring arm 20.
The support element joint device 43 thereby allows the support element 30, i.e. the plate element 36, to rotate about one axis only, i.e. the axis A indicated in
The joint device 28 of the second embodiment of the mooring device 10 further comprises an attachment unit joint device 61 for attachment of the joint device 28 to the attachment unit 66.
The attachment unit joint device 61 may be a cardan joint, allowing the attachment unit 66 to rotate about two independent axes relative to the support element 30. Alternatively, as shown in
The joint device 28 of the third embodiment of the mooring device 10 shown in
The holder element 38 comprises a cavity in which the ball support element 63 of the attachment unit joint device may be mounted. As can be seen on
The joint device 28 of the third embodiment of the mooring device 10 further comprises a support element joint device 43 comprising a first mooring arm joint device 58 that is generally fork-shaped or U-shaped and a second mooring arm joint device 59 that is generally fork-shaped or U-shaped and has a size and shape that makes it fit into the fork-shaped first mooring arm joint device 58.
The first mooring arm joint device 58 is securely attached to the first end portion 15 of the first mooring arm 12 and the second mooring arm joint device 59 is securely attached to the first end portion 23 of the second mooring arm 20.
The first mooring arm joint device 58 and the second mooring arm joint device 59 may be rotatably connected to the first pin element 39 and the second pin element 40 of the support element 30 allowing the support element 30 to rotate relative to both the first mooring arm 12 and the second mooring arm 20.
However, it is preferable that the first mooring arm joint device 58 is securely attached to the support element 30, for example to the first pin element 39 and/or the second pin element 40, and that the second mooring arm joint device 59 is rotatably connected to the support element 30, i.e. to the first pin element 39 and the second pin element 40. Alternatively, the second mooring arm joint device 59 is securely attached to the support element 30, for example to the first pin element 39 and/or the second pin element 40, and the first mooring arm joint device 58 is rotatably connected to the support element 30, i.e. to the first pin element 39 and the second pin element 40.
A slightly different variant of the third embodiment is shown in
The first mooring arm joint device 58 of the support element joint device 43 is here shown as an element 58 that is securely attached to the support element 30, for example to the holder element 38, by welding, bolting or any other suitable fastening method. The first end portion 15 of the first mooring arm 12 is securely attached to the element 58 and is thereby securely attached to the support element 30. It would also be possible to leave out the first mooring arm joint device 58 and just weld or bolt the first end portion 15 of the first mooring arm 12 directly to the support element 30. The first mooring arm joint device 58 would then simply be a weld or bolts/boltholes that connects the first end portion 15 to the support element 30.
The second mooring arm joint device 59 is fork-shaped in the same way as shown in
This configuration of the joint device 28 of the third embodiment of the mooring device 10, including the fork-shaped first mooring arm joint device 58 and fork-shaped second mooring arm joint device 59 as shown in
The support element joint device 43 thereby allows the support element 30 to rotate about one axis only which is perpendicular to a plane formed by the longitudinal axis of the first mooring arm and the longitudinal axis of the second mooring arm, where the axis A passes through the bolt element 46 as indicated in
It was mentioned above that the joint device 28 of the third embodiment of the mooring device 10 further comprises an attachment unit joint device 61 for attachment of the joint device 28 to the attachment unit 66. The attachment unit joint device 61 may be a cardan joint, allowing the attachment unit 66 to rotate about two independent axes relative to the support element 30. Alternatively, as mentioned above and shown in
The various embodiments of the mooring device 20 preferably further comprises one or more support arms 97 comprising a first end portion 100 and a second end portion 103 as indicated in for example
The support arm 97 is preferably telescopic as is shown in for example
The first telescopic part 98 of the support arm 97 comprises the first end portion 100 of the support arm 97. Likewise, the second telescopic part 99 of the support arm 97 comprises the second end portion 103 of the support arm 20.
A first attachment joint device 101 is preferably attached to the first telescopic part 98 of the support arm 97 and is adapted for attachment of the first attachment joint device 103 to a support element 30 of the joint device 28. The first attachment joint device 101 preferably allows the support arm 97 to rotate about three independent axes relative to the support element 30 and may be a ball joint or a universal joint or any other type of joint that allow the support arm 97 to rotate about three independent axes relative to the support element 30.
A second attachment joint device 104 is preferably attached to the second telescopic part 99 of the support arm 97 and is adapted for attachment of the second attachment joint device 104 to a floating unit 110 or a floating or non-floating structure 125. The second attachment joint device 104 preferably allows the support arm 97 to rotate about three independent axes relative to the floating unit 110 or a floating or non-floating structure 125 to which the mooring arm 10 is attached, and may be a ball joint, a universal joint or any other type of joint that allow the support arm 97 to rotate about three independent axes relative to the floating unit 110 or a floating or non-floating structure 125.
The support arm or support arms 97 may be arranged above the first mooring arm 12 and the second mooring arm 20, as indicated in for example
The configuration of the mooring device 10 described herein will allow the floating unit 110 some freedom to move relative to the floating or non-floating structure 125. The attachment unit 66 of the mooring device 10 will be attached to the floating or non-floating structure 125 when the floating unit 110 is moored to the floating or non-floating unit 125. In
The floating unit 110 may be provided with at least one, but preferably at least two fender devices 120, 121, a first fender device 120 and a second fender device 121 as indicated in
The first and second fender devices 120, 121 may be flexible to a certain degree as indicated in
The flexibility and compressibility of the first and second fender devices 120, 121 may be obtained by using air pressurized elements that are made of a flexible material such as a rubber material. The fender elements 120, 121 may further be filled with foam or rubber. The pressure of air or the stiffness of the foam or rubber inside the fender elements 120, 121 may be adjusted so that a desired compressibility of the first and second fender devices 120, 121 is obtained. As shown in the figures, the floating unit 110 may be provided with one or two mooring devices 10 arranged between the first fender device 120 and the second fender device 121. However, any number of mooring devices 10 may mounted on the floating unit 110 and any number of fender devices 120, 121 may be mounted on the floating unit 110. The arrangement and the relative and mutual positions of the individual fender devices 120, 121 and the mooring device 10 or mooring devices 10 may also vary from one floating unit 110 to another floating unit 110. The fender devices 120, 121, if located on the outside of the mooring devices 10, will help absorb yaw moments of the floating unit 110. Providing a floating unit 110 with one or more fender devices 120, 121 in addition to one or more mooring devices 10, therefore enhances the usability of the mooring devices 10 since external loads acting on the floating unit 110 can at least partly be handled by the one or more fender devices 120, 121, thus reducing the design requirements for the mooring devices 10.
Finally, it should be mentioned that all the above-mentioned embodiments illustrate the invention. However, without limiting the invention, the skilled artisan in the field will be able to contemplate many alternative embodiments without deviating from the scope of the enclosed claims. In the claims, reference numbers in brackets shall not be construed as limiting.
It should be mentioned that the use of the verb “to comprise” herein and its different forms do not exclude the presence of elements or steps which are not mentioned in the claims. The article “a” before an element do not exclude the presence of several such elements.
Number | Date | Country | Kind |
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20180263 | Feb 2018 | NO | national |
20181650 | Dec 2018 | NO | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2019/053855 | 2/15/2019 | WO | 00 |