| JP59206286 | PARALLEL CABLE FOR MOORING MARINE FLOATING STRUCTURE |
| JP59161525 | WORKING SHIP |
| WO/2012/069835 | TRANSFER APPARATUS |
| CLAIMS 1 Apparatus for stabilising a floating craft against a stationary structure, said apparatus comprising means of attaching the apparatus to a floating craft, an elongate fender, said fender comprising a structure contacting face, with said apparatus further comprising at least two jaws, each of said jaws comprising a front face and a structure contacting surface, wherein at least one jaw is movable from a first position to a second position and vice versa, in order that said jaws may be positioned in a first open position where the structure contacting surfaces of the jaws are relatively far apart and a second closed position wherein the structure contacting surfaces of the jaws are relatively close together, wherein when said apparatus is positioned such that a suitably sized part of the stationary structure is placed between the jaws, the said jaws can be brought into the closed position, thereby creating craft stabilising contact between the structure contacting surfaces of the jaws and the structure. 2 Apparatus according to claim 1, wherein there are two jaws. 3 Apparatus according to claim 1 or claim 2, wherein each of the jaws comprises actuation means, and each can move separately from the other or others. 4 Apparatus according to any of the preceding claims, wherein each of the jaws comprises a pad of resiliently deformable material. 5 Apparatus according to claim 4, wherein each pad is rubber. 6 Apparatus according to any of the preceding claims, wherein the fender can be moved from a first position, in which the structure contacting face of the fender forms a substantially planar surface with the front faces of said jaws, to a second, withdrawn position. 7 Apparatus according to claim 6, wherein when the fender is in the withdrawn position, the jaws can be moved substantially across the structure contacting surface of the said fender. 8 Apparatus according to claim 7, wherein the fender comprises a plurality of side surfaces, wherein the side surfaces of the fender and the structure contacting surfaces of the jaws are so shaped as to fit together when the fender is in the first position. 9 Apparatus according to claim 8, wherein the side surfaces of the fender and the structure contacting faces of the jaws comprise a plurality of interlocking teeth. 10 Apparatus according to any of the preceding claims, wherein the jaws are attached to the rest of the apparatus via ball joints. 11 Apparatus according to any of the preceding claims, wherein the means of actuation of at least a jaw or the fender comprises a pneumatic ram. 12 Apparatus according to any of claims 1 to 10, wherein the means of actuation of at least a jaw or the fender comprises a hydraulic ram. 13 Apparatus substantially as described herein, with reference to and as illustrated by any appropriate combination of the text and / or drawings. 14 A floating craft, comprising apparatus according to any of the preceding claims. 15 A floating craft, comprising apparatus substantially as described herein, with reference to and as illustrated by any appropriate combination of the text and / or drawings. |
Field of the Invention
This invention relates to apparatus for stabilising a floating craft against a stationary structure, such as the stability of craft such as boats in open and active waters when delivering or receiving personnel or goods at a stationary structure. The invention has particular application in relation to offshore structures such as wind turbines.
Prior art and problems to be solved
As the resources available from the land become more scarce, the world looks to the seas for energy, either in terms of deep sea oil, or in terms of renewable energy sources, such as tidal and in particular wind power. In order to facilitate the exploitation of such energy sources, there has been a proliferation of offshore structures and in particular offshore wind farms. Often these structures are too small to provide full docking facilities for a craft, and as such it is the case that when a structure such as a wind turbine requires renovation and / or repair, it can be problematic to dock with it, and transfer equipment and/ or personnel to it.
Typically, access to a wind turbine will be via a ladder running along the length of the stem of the turbine, and in order to gain access to the turbine, a craft will have to be very carefully moved up alongside it to the extent that personnel can simply get onto the ladder, or the transfer can be made via a smaller craft such as a dinghy, or via a gangplank. In conditions of all but calm, it can be the case that the old methods are at best difficult and haphazard, and at worst can be dangerous. Further, the use of a dinghy may be impracticable for the transport of heavy equipment.
A prior attempt to solve this problem is contained in EP1695902B1 WINDCAT
WORKBOATS LIMITED. In this invention, relative safety was promised, through a combination of factional engagement between a fender positioned at the bow of a craft and the stationary structure, and the urging force provided by the motor of the craft.
One shortcoming of the WINDCAT document is that it only focuses itself on alleviating problems related to downwards motion, where a key problem can be that a craft is tossed from side to side relative to a turbine pylon. These sideways motions, either in themselves or in combination with the upwards and downwards motions can be most severe, causing damage to craft, and injury and loss of life to crew thrown from the craft, or are hit by a returning craft after they have been transferred to the structure. In particular, where wind turbines have landing tubes, it has been known for boats to get stuck on the tubes.
The method of the prior art exacerbates this problem by requiring the boat to constantly urge itself towards the pylon. In a current, this urging force can easily be misdirected, resulting in damage and / or injury.
It is amongst the objects of the invention to provide solutions to these and other problems.
Summary of the invention In a first broad, independent aspect, the invention comprises apparatus for stabilising a floating craft against a stationary structure, said apparatus comprising means of attaching the apparatus to a floating craft, an elongate fender, said fender comprising a structure contacting face, with said apparatus further comprising at least two jaws, each of said jaws comprising a front face and a structure contacting surface, wherein at least one jaw is movable from a first position to a second position and vice versa, in order that said jaws may be positioned in a first open position where the structure contacting surfaces of the jaws are relatively far apart and a second closed position wherein the structure contacting surfaces of the jaws are relatively close together, wherein when said apparatus is positioned such that a suitably sized part of the stationary structure is placed between the jaws, the said jaws can be brought into the closed position, thereby creating craft stabilising contact between the structure contacting surfaces of the jaws and the structure. This configuration has numerous advantages over the prior art configurations. First, the jaws can be used to exert control over the relative lateral movement of the craft in relation to the stationary object, which makes it less likely for the craft to be become damaged by, or stuck on the stationary object, as has occurred with craft using prior art bow fenders. Second, the provision of jaws, at least one of which is movable, allows for adjustment of the contact between the craft and the stationary structure, as a supplement to and independently of any force created by the engine of the craft - thus potentially solving the problem of misdirected engine force mentioned previously. In a first subsidiary aspect, there are two jaws.
The provision of two jaws only, allows for simple and effective pincer movements to be utilised in stabilising the craft. Further, an embodiment with only two jaws presents the jaws in their simplest form, and one which may be made easier to operate than a larger number.
In a second subsidiary aspect, each of the jaws comprises actuation means, and each can move separately from the other or others.
The provision of separate actuation means for each of the jaws, allows for the individual adjustment of the position of each jaw, thereby allowing for the said position to be adapted in relation to the contours of different stationary structures. In a third subsidiary aspect, each of the jaws comprises a pad of resiliently deformable material. In a fourth subsidiary aspect, each pad is rubber.
The provision of pads, and rubber pads in particular, reduces the occurrence of damage caused by the repeated contact between the jaws and the structure. In a fifth subsidiary aspect, the fender can be moved from a first position, in which the structure contacting surface of the fender forms a substantially planar surface with the front faces of said jaws, to a second, withdrawn position.
The presence of a fender which is movable in this way is advantageous because it allows for the creation of a recess after contact is made with the fender - the user can position his craft so that a part of the stationary structure is in contact with the fender, and then retract the fender, thus creating the recess, allowing for the precise drawing of the craft to the structure. A further advantage of this is that when the transfer of goods or people is finished, the fender can be restored to the first position, thereby pushing the craft away from the structure.
Preferably, when the fender is in the withdrawn position, the jaws can be moved substantially across the structure contacting surface of the said fender.
This configuration is particularly advantageous, because here the jaws effectively form the sides of the recess, and as such, the size of the recess can be varied, in accord with the desired level of overall movement or movement in a given direction.
More preferably, the fender comprises a plurality of side surfaces, wherein the side surfaces of the fender and the structure contacting faces of the jaws are so shaped as to fit together when the fender is in the first position. More preferably still, the side surfaces of the fender and the structure contacting faces of the jaws comprise a plurality of interlocking teeth. The provision of a fit between fender and jaws, and especially the provision of interlocking teeth, is advantageous because it allows for a continuous surface to be presented to the elements, which is stronger and more resistant to the elements and/or a collision, than an irregular surface. Further, a continuous surface is far more aerodynamic than an irregular surface.
In a sixth subsidiary aspect, the jaws are attached to the rest of the apparatus via ball joints.
Ball joints allow for the adjustment of the angle of the jaws to the contours of a given stationary structure. They provide the flexibility necessary to allow the craft to move with the water relative to the stationary structure - if they were stiffly jointed to the rest of the apparatus, this movement would tend to break the jaws off of their attachments.
In a seventh subsidiary aspect, the means of actuation of at least a jaw or the fender comprises a pneumatic ram.
In an eighth subsidiary aspect, the means of actuation of at least a jaw or the fender comprises a hydraulic ram. The use of such rams provides a strong and reliable means of moving the jaws and / or fenders through a series of positions and to lock it in such positions.
The invention also comprises apparatus substantially as described herein, with reference to and as illustrated by any appropriate combination of the text and / or drawings.
In a second broad, independent aspect, the invention comprises a floating craft, comprising apparatus according to any of the preceding claims. The invention also comprises a floating craft, comprising apparatus substantially as described herein, with reference to and as illustrated by any appropriate combination of the text and / or drawings. Brief description of the figures
The invention will now be described by way of example and with reference to the accompanying schematic drawings, wherein: Figure 1 is a plan view of a portion of a craft bearing apparatus of the invention, in a first position.
Figure 2 is a plan view of a portion of a craft bearing apparatus of the invention, in a second position.
Figure 3 is a plan view of an interconnecting jaw portion and an interconnecting fender portion.
Figure 4 is a plan view of a further embodiment of the invention.
Figure 5 is a side view of a craft, stabilised against a stationary structure via apparatus of the invention.
Detailed description of the preferred emobodiments
Figure 5 shows a craft 2 held relative to an offshore structure 8 by engagement of its bow 4 against a pylon 6 of the offshore structure 8. The craft 2 is shown at a slight incline relative to the sea 10, with its bow 4 above its stern 12. The bow 4 has on it apparatus of the invention 14, which is visible from the side. The apparatus 14 is aiding the stabilisation of the craft 2 relative to the offshore structure 8, in particular against lateral movement. In the embodiment shown, the craft 2 is of a single hull design, and the jaw 24 projects out of the side and / or the front of the craft 2. At figure 1, the apparatus 14 is shown disengaged from the offshore structure 8, which comprises landing tubes 6 and a ladder 9. Here the apparatus 14 has been fitted to a craft 16 which is a catamaran, and has been incorporated into the craft 16 by way of apertures 18, through which the apparatus is attached. Alternative embodiments offer means of attaching the apparatus 14 to the craft 16 without permanently altering the craft 16 - clamping means 22, which are utilised to hold a part of the apparatus 14 in place at figure
1, can be used to hold the entire apparatus 14 in place, in other embodiments. Other means of attachment will be available, but in choosing an appropriate attachment means it must be borne in mind that the means must be resistant to water and in particular sea water, in order to be suitable for offshore use. It will be appreciated that in preferred embodiments the apparatus 14 can be detachable for repair and for use on other crafts. The apparatus 14 may be used on crafts with a single hull or a multiple hull.
The apparatus 14 is most commonly situated at the bow 20 of a craft 16, but might just as well be fitted at the stern of a craft, or at a side of a craft. Where the craft 16 is a catamaran, as in figure 1, the apparatus 14 may be located between the bows 20.
The apparatus 14 comprises, in its simplest form, jaws 26 and a fender 28.
In this embodiment, both of the two jaws 26 and the fender 28 are movable, but in alternative embodiments, the fender 28 and all but one of the jaws 28 may be static. In particular, the fender 28 may be static in the second "retracted" position, shown at figure
2. The fender 28 is elongate in form and has a structure contacting face 60, and two side faces 62. At figure 3, it is shown that the fender 28 has teeth 64 on its side face(s) 62 which interlock with the teeth 66 on structure contacting surface 52 of jaw 26, although other shapes suitable for interlocking, including teeth of a non-crenellated profile may be considered.
At figure 1, the fender 28 is in the extended position, but may be moved into the retracted position of figure 2. In preferred embodiments it is possible to stop the movement of the fender 28 and / or the jaws 26. In the embodiment of figure 1, the means of moving fender 28 and jaws 26 is one or more hydraulic rams 30, although pneumatic rams provide a reasonable alternative. Other means of moving the fender and jaws, including manual, mechanical, and electric means are contemplated. The hydraulic rams 30 are mounted to framing pieces 31, 33. The number of rams 30 may vary, but two rams 30 or The route taken by the movement of the jaws 26 and fender 28 respectively, may be be lined by liner 35 which may be of rubber. This advantageously reduces friction and protects the fender 28, the jaws 26 and the parts of apparatus or craft which they would otherwise move against.
The fender 28 is made of a resilient, material - natural or synthetic rubber is particularly favoured, but other materials may be suitable. It has been found that a rubber sleeve around a resilient form core is a particularly useful combination for jaws 26 and fender 28, but other combinations may work equally well. The jaws 26 feature pads 32 which are also made of natural or synthetic rubber. Pads 32 comprise a front face 50 and a structure contacting surface 52. Behind pads 32 is a moulding 54, with a channel 56 through which the pad moving component 58 runs. The pads 32 are attached to the pivot 34 via ball joints 36. The balls joints 36, along with the resilient material of the fender 28 and jaws 26, serve to disperse and deflect the force of repeated impacts between those portions (and the craft in general) and a stationary structure.
In order that the jaws 26 can be moved together and apart, there are jaw rams 38, which extend to move the jaw 26 closer and retract to move the said jaws 26 further apart. The jaw rams, 38 which may be configured so as to be controlled independently or separately, are connected to a control means (not shown) selected by the skilled man. Jaw rams 38 may act directly on jaws 24, or they may move jaw actuation apparatus 39 about a pivot 34 - the location of two such fulcrums are shown, in figures 1 and 4 respectively, although this should not be considered to limit the location of the pivot points. An alternative configuration might have jaw apparatus 39 turning about a directly powered shaft, (not shown) the turning motion being powered by means known to the skilled man.
In use, the craft 16 is moved into a position where it is in contact with, or at least adjacent to, the structure 8, with the structure contacting surface 60 of the fender 28 being brought as close as possible to the structure 8 - ideally, a broad contact with the structure 8 is made. The fender 28 can then be retracted from the position in figure 1 into the position in figure 2, creating a recess 62 At least a part of the structure 8 may now be accommodated by the recess 62, with the landing tubes 9 partially surrounded. The jaws 26 can now be moved towards one another, thereby moving in front of or across contacting surface 60, with the result that the jaws 26 form at least a steadying, intermittent contact with the structure 8 - preferably a continuous contact, and more preferably a factional fit, or a hold or grip. This serves to steady the craft 2 relative to the structure 8, and allows the transfer of people and equipment.
In preferred embodiments, the structure contacting surface 60 is flat, substantially forming a plane perpendicular to the surface to which it is desired that contact be made; non-flat contacting surfaces are however covered by the scope of this patent.