Patent ID: 12221193

A first illustrative embodiment of the invention will be described with reference toFIGS.1to7. In this embodiment, the marine transfer apparatus is used in conjunction with an offshore wind turbine generator1and is used to allow a user to transfer from a vessel20to a platform2provided on the wind turbine generator1. In this respect,FIG.1shows a vessel20docked against the body of the wind turbine generator1, with the vessel's bow braced against the surface of the wind turbine generator1to help to restrain movement of the vessel20in the waves21. As shown, the platform2of the wind turbine generator is provided with a climbing attachment structure3. In embodiments, the climbing attachment structure3may form part of a powered hoist used as the primary mechanism for lifting loads, including personnel. As such, the climbing attachment structure3is used for a secondary purpose as part of the present arrangement to provide an elevated position for mounting a coupling part4.

In this connection, the coupling part4is provided as a ring-shaped body having a central aperture and an upper mounting plate which is bolted onto the climbing attachment structure3. The main body of the coupling part4, as is described in further detail in reference toFIG.6, has a torus or another suitable shape, which forms an inflexible supporting structure around the aperture. An alternative coupling part4is illustrated inFIG.8. As with the first example, this second example has a central aperture and a ring-shaped body. The ring-shaped body is integrated into the coupling part's mounting plate. The mounting plate has a lateral plane perpendicular to the lateral plane of the ring-shaped body and allows the coupling part4to be bolted or otherwise fixed onto the climbing attachment structure3. Accordingly, in this example, the ring-shaped body of the coupling part4has the appearance of having a removed segment, with the body and mounting plate being merged. This provides a more compact and sturdy arrangement. It will be understood that the coupling part may be formed by casting. For example, the body of the coupling part4may be formed as two semi-circle parts that are welded together and are then bolted and/or welded to the mounting plate.

In this first illustrative embodiment, the drag line5is provided as a loop of rope which extends through the coupling part's aperture. The drag line5is attached close to sea level of the offshore structure by a lower mounting point6, which is provided as a second pulley. In embodiments, this may be a simple bearing shaft, which the drag line runs freely over, which may be mounted using magnets to the body of the foundation supporting the wind turbine. In other embodiments, such as the second embodiment described below, the drag line5may be provided as a line with two ends, such that it may be fed completely through the coupling part4and disconnected from it once a climbing line has been hoisted up.

The drag line5is further provided with a carabiner7which is attached at a fixed point on the rope of the drag line5and provides a reversible connector. It will be understood that the drag line5may be pulled around by a user to feed it through the coupling part4and the lower mounting point6. As such, the carabiner7can be raised up to the coupling part4, dragged through its aperture, and then lowered back toward the vessel20.

As shown inFIG.2, a climbing part8is used in combination with the drag line5and coupling part4. In this embodiment, the climbing part8comprises three rope lines; a primary climbing line8a, a back-up secondary climbing line8band a rescue line8c. A first end of climbing part8terminates in a fastener connector9, as shown inFIG.7. As such, the three rope lines8a-care attached to the ring-like body of the fastener connector9, which allows the first end of the climbing part8to be connected to the carabiner7. As shown inFIG.2, this thereby allows the first end of the climbing part8to be attached to the carabiner7and lifted as the drag line5is fed around its mounting.

As shown inFIG.3, the second end of the climbing part8terminates in a locking member10. The locking member10is shown in further detail inFIGS.5and6, and is provided as a disk-shaped plug into which the three rope lines8a-care attached. The locking member10is sized such that it does not fit through the aperture of the coupling part4. Consequently, once the climbing part8is fed through the coupling part4to its second end, the locking member10braces against the support ring of the coupling part4and plugs the aperture formed therein. This thereby forms a one-way fit, loadbearing connection for each of the three rope lines8a-cto the coupling part4. In other embodiments, the locking member10and coupling part4may also engage magnetically, by Velcro fastening, friction or any other relevant means to form a pseudo-permanent bond. This may allow, for example, the wear and tear of the drag line5to be minimised when not loaded and following the ship's movements in the sea.

In use, the vessel20may be driven into the wind turbine generator1to brace its bow. The vessel20will carry the climbing part8, and a user may then attach the fastener connector9to the carabiner7. As shown inFIG.2, the drag line may then be pulled by the user to lift the first end of the climbing part8toward the elevated position. In the illustration, the climbing part8is held in a bag81and feeds out from there as the fastener connector9is hoisted upward.

When the fastener connector9reaches the coupling part4, it is dragged through the aperture by the connection carabiner7, which draws through the three rope lines8a-c. As shown inFIG.3, the fastener connector9begins descending back toward the vessel20, drawing the three rope lines8a-cfurther through the coupling part4. This process is continued until the locking member10reaches the coupling part4, to form the locking connection shown inFIG.6. At this stage, the fastener connector9can be detached from the carabiner7, allowing the three rope lines8a-cto hang freely from the coupling part.

As shown inFIG.4, a user12may attach an ascender/descender device11to the primary climbing line8aand use the rope to ascend to the elevated position allowing them to access the platform2. The user12may simultaneously connect to the primary climbing line8bas a backup connection. The rescue line8ccould be used to reach the user12in the event of an emergency.

Once the user12has ascended and/or descended, the climbing part8may be detached from the coupling4by connecting the fastener connector9to the carabiner7and then feeding the drag line5in the opposite direction. The slack provided on the climbing part8, together with the action of the drag line5acts to dislodge the locking member10from the coupling part4, allowing it to then be lowered as the drag line moves the carabiner7back toward the coupling. This process is continued until the carabiner7has carried the fastener connector9back to the vessel, where it can be detached to allow the climbing part8to be removed and used at a different site.

FIGS.9and10show a locking member end of a climbing part according to a second illustrative embodiment. In this embodiment, the drag line5is provided as a line with two ends, such that it may be fed completely through the coupling part4and disconnected from it once a climbing line has been hoisted up. That said, the device otherwise operates in substantially the same way as the first embodiment. In this embodiment, the locking member30has, within the boundary of its circular anchor plate, a central aperture31surrounded by four outer apertures32, as shown inFIG.10. The four outer apertures32are spaced equidistant from each other around the central aperture31.

As shown inFIG.9, a pull-down cord33is securely fastened to the central aperture31. The pull-down cord33enables the locking member30to be disengaged from the coupling part4once operations are finished and the climbing part is no longer needed. To disengage the locking member30from the coupling part4, a user can pull on the pull-down cord33which releases the locking member30from the coupling part4. As mentioned above, in this second illustrative embodiment, the drag line5is provided as a length of rope, with one end coupled close to sea level on the offshore structure at a lower mounting point6, and a carabiner7is attached to the other end. The drag line5is installed so that it passes through the coupling part's aperture, such that the drag line5may be drawn through the aperture by a user lift the climbing part8.

As shown inFIG.9, in this embodiment, the locking member end includes two anchor slings34, provided as closed loops of webbing. Each anchor sling is passed through two of the outer apertures32, such that each anchor sling34forms two anchor sling loops from the sling ends extending from the respective two outer apertures32. The anchor sling loops are coupled together by respective connector rings35. As such, a separate connector ring35is used for each anchor sling34. The edges of the outer apertures32of the locking member30can be filleted, or rounded, to reduce friction between the outer aperture32and the anchor slings34, and to increase the strength of the locking member30by distributing the load more evenly.

Two rigging plates36are coupled to the connectors35from the anchor slings34, with the two plates shown next to one another in the drawing. The provision of at least two rigging plates36provides for redundancy, such that if one of the rigging plates36were to fracture during operation, the other rigging plate36still provides back-up load baring capacity. The rigging plate36has a main aperture37, through which the ring connectors35of the anchor slings34are coupled, and three lower apertures38. A connector ring35is coupled to each of the lower aperture38, and each of these connectors35is coupled to one of three rope lines8a-c.

In operation, the carabiner7may be initially releasably secured to the lower mounting point6when not in use, with the drag line5being looped up through the coupling part4. When used, a user detaches the carabiner7and connects the fastener connector9of the climbing part8. The drag line5may then be used to drag the carabiner7, and hence the climbing part8, up through the coupling part4until the carabiner7is lowered back toward the vessel20. As with the first embodiment, the three rope lines8a-care drawn through the coupling part4until the locking member30reaches the coupling part4, to form a locking connection. One or more of the rope lines8a-ccan then be used as climbing lines for ascending or descending the structure. In reverse, the pull-down cord33enables the carabiner7of the drag line5to be passed back through the coupling part4when the user pulls the pull-down cord33. In so doing, the carabiner7of the drag line5is returned to its original position, such that it can be used again.

It will be understood that although in the above illustrative second embodiment redundancy is built into the arrangement with duplicate connections between coupling parts, other embodiments may have simpler coupling arrangements. For example, rather than two anchor slings34and two rigging plates36, as shown inFIG.9, other embodiments may have a single anchor sling and/or a single rigging plate forming the connections. Such parts may, for instance, be additionally reinforced to mitigate any safety risks of having reduced redundancy.

FIG.11shows a third illustrative embodiment. This embodiment is substantially the same as the first embodiment, but further includes a tensioner mechanism13for tensioning the drag line5into a retracted position. As shown, the tensioner mechanism13includes a pulley which draws the drag line upward. As such, the drag line5can be mounted in a more elevated position on the foundation, above the waterline and away from the waves21and vessel engagement location. This is especially relevant in areas with a high tide. To access the drag line5, a user may hook the line with a hook pole from the vessel20and draw the drag line5out against the resilience of the tensioner13. The user can then connect the fastener connector9to the carabiner7to connect the climbing part8to the coupling, as with the first embodiment. As such, this may thereby help to preserve the integrity of the drag line5and mitigate the risk of mechanical damage which may otherwise arise if the drag line5is loose.

It will be understood with the above arrangements, a wind turbine engineer or other user can use the drag line5to feed the locking member10through the coupling part5to form a locking engagement therebetween. Once in place, the user can use the primary climbing line8ato ascend up to the platform2. As the apparatus may be operated manually, the risk of mechanical breakdown is avoided. At the same time, only the drag line5needs to remain on-site at the wind turbine generator1and, even then, this line does not have a load bearing function during ascent. As such, the drag line's extended exposure to environmental conditions does not present a hazard. Similarly, the integrity of the climbing line can be preserved, and the line may be inspected prior to use to maintain safety. Therefore, the climbing line can be used to provide safe access to an offshore structure from a vessel, without needing to rely on a powered hoist or ladder.

It will be understood that the embodiments illustrated above show examples only for the purposes of illustration. In practice, embodiments may be applied to many different configurations, the detailed embodiments being straightforward for those skilled in the art to implement.

For example, whilst reference has been made to various ‘lines’, it will be understood that these may be provided as ropes, cables, or chains, for example. Equally, whilst the illustrative embodiments have been disclosed with three lines, it will also be understood that different numbers may be provided.