Background The present invention relates to a method for coupling a manoeuvrable vessel to a floating structure.

Such a method is known from EP0670392A1 wherein a device is disclosed having a conduit coupling whose one coupling part extends at the outlet of a pressure conduit of a suction dredger over the bow. The other coupling part of the device is provided as a floating hose conduit formed as the end of a flushing tube conduit. A pickup line is coupled to the floating hose. Upon hauling in of the pickup line, the one and the other coupling part are brought together and coupled for transport of dredge under pressure.

The known method for coupling is disadvantageous since while manoeuvring the vessel, sight to the floating hose and pickup line is poor. As a result thereof, damage may occur or coupling procedures may take more time, in particular under severe weather and heavy sea conditions. In addition, the known method is cumbersome and unsafe for personnel. This is particularly true in coastal waters in stormy weather and rough seas.

Generally, a suction dredger transports dredge or soil from the bottom of a body of water, especially from the ocean floor near the coast to the shore over a greater distance and rinsed there a floating line for the recovery of land for tilling land.

Summary of the invention

The invention aims to provide a method to facilitate coupling of a manoeuvrable vessel to a floating structure, wherein the method is more safe for personnel and allows operations at more severe sea conditions.

Another object of the invention is to solve, at least partly, a problem associated with known methods for coupling of a manoeuvrable vessel to a floating structure.

Yet another object of the invention is to provide an alternative method for coupling of a manoeuvrable vessel to a floating structure. According to a first aspect of the invention this is realized with a method for coupling a manoeuvrable vessel to a floating structure, the method comprising;

- providing a pickup system coupled to the floating structure, the pickup system comprising a float,

- providing a manoeuvrable vessel comprising a coupling device for coupling the vessel to the floating structure, the coupling device comprising manoeuvrable coupling means on the manoeuvrable vessel,

- aiming the manoeuvrable coupling means towards the pickup system,

- guiding the manoeuvrable coupling means towards float coupling means of the pickup system, such that the manoeuvrable coupling means engage the float coupling means in a coupling manner,

- locking the float coupling means with respect to the manoeuvrable coupling means, such that a coupling connection between the manoeuvrable vessel and the floating structure is established,

- connecting the floating structure to the coupling vessel for transport of

fluidized matter, like dredge between the vessel and the floating structure. The method provides an improved coupling wherein a distance between the floating structure and the vessel may be observed in order to prevent damage while still being able to provide a coupling connection between the manoeuvrable vessel, also referred to as coupling vessel, and the floating structure. In other words, the method provides an improved window of operation with respect to e.g. heavy sea conditions. This enables an improved usability of costly equipment like a dredger hopper at sea.

It will be understood that the manoeuvrable coupling means may be part of the float. Important is that a difference in vertical movement between the float and the vessel can be accommodated by manoeuvrable coupling means such that the float and the vessel do not bump. The manoeuvrable coupling means may be part of the vessel and/or the float.

According to a further aspect of the invention, this is realized with a coupling system for connecting a floating structure a manoeuvrable vessel, in particular the bow of the manoeuvrable vessel, the bow coupling system comprising a pickup system and a coupling vessel, whereby the pickup systems comprises at least a float for buoyancy of the floating structure on a water surface and a float coupling means connected to the at least one float, which float coupling means extends from the float above the water surface, and whereby the coupling vessel comprises a coupling device having manoeuvrable coupling means for engaging the float coupling means of the pickup system, such that a coupling connection between the manoeuvrable vessel and the floating structure is obtained.

In an embodiment of the coupling system, the coupling connection is obtained by accommodation of the manoeuvrable coupling means in the float coupling means. This even more facilitates to establish a coupling connection between the vessel and the floating structure.

In an embodiment, the coupling device is articulated and comprises;

a leading coupling device member provided with the coupling means for engaging the float coupling means of the pickup system,

a trailing coupling device member configured to be supported by the vessel in a hingeable manner, and hingeably coupled with the leading coupling device member, and provided with a conduit coupling means,

wherein the leading coupling device member and the trailing coupling device member are mutually hingeable between a retracted position and a extended position of the coupling device wherein the coupling means and the conduit coupling means are arranged with respect to the coupling device such that, in the extended position of the coupling device the coupling means and the conduit coupling means are remote with respect to each other and the coupling means extend toward the water surface, and in the retracted position of the coupling device the coupling means and the conduit coupling means are about vertically aligned.

In an embodiment of the coupling system, the trailing coupling device member is hingeably coupled with the leading coupling device member at their respective coupling ends, the coupling means are situated at a free end of the leading coupling device member opposite its respective coupling end, and the conduit coupling means are situated at a free end of the trailing coupling device member opposite its respective coupling end. In an embodiment of the coupling system, the trailing coupling device member is configured to be supported by the vessel in a hingeable manner proximate the conduit coupling means and opposite its respective coupling end.

According to an even further aspect of the invention, this is realized with a floating structure comprising a pickup system suitable for raising at least a part of the floating structure above the water surface, wherein the pickup system comprises an erected elongate float which float extends partly above the water surface, and wherein the float comprises a float coupling means for cooperation with a vessel coupling means associated with a manoeuvrable vessel which intends to couple with the floating structure. The pickup system is configured such that it may raise at least a part of the floating structure above the water surface. Whether this actually will happen depends. Important is that at least a part of the float moves in unity with the pickup unit, more specifically the manoeuvrable coupling means thereof. It is conceivable that the float is articulated and therefore in practice no part of the float will raised above the water.

In an embodiment of the floating structure, the float coupling means is arranged at an upper end of the float. This facilitates sight of an operator of the vessel on the coupling means itself which even more facilitates to establish a coupling connection between the vessel and the floating structure.

In an embodiment, the floating structure comprises a slimline portion beneath the coupling means, in use proximate the water surface, for decreasing movement of the float in particular under rough sea conditions. This even more facilitates to establish a coupling connection between the vessel and the floating structure.

In an embodiment of the floating structure, the float comprises orientation means for an operator of the manoeuvrable vessel to facilitate orientation. This even more facilitates to establish a coupling connection between the vessel and the floating structure.

In an embodiment of the floating structure, the orientation means are arranged above the float coupling means. In an embodiment of the floating structure, the pickup system comprises a pair of erected elongate floats, and wherein the float coupling means and/or the orientation means extend between the floats. The pair of floats aid in stabilizing the pickup system and therefore facilitates in establishing a coupling connection between the vessel and the floating structure.

More particular it is preferred that the floating structure comprises a floating conduit having a free end, and wherein the pickup system is coupled with the free end for raising the free end above the water surface.

According to a further aspect of the invention, this is realized with a

manoeuvrable vessel, comprising a coupling system for coupling a vessel to an adjacent floating structure according to the invention to the vessel.

In an embodiment of the manoeuvrable vessel, the coupling system comprises manoeuvrable coupling means manoeuvrable with respect to the vessel for

compensating movement of the float in particular under rough sea conditions. It is particularly important to compensate for vertical movement of the vessel relative to the float.

In an embodiment of the manoeuvrable vessel, the manoeuvrable coupling means is hingeable between a substantially horizontal position wherein the coupling means is engageable with float coupling means associated with a floating structure the manoeuvrable vessel intends to couple with, and a raised position for coupling the float with the manoeuvrable vessel.

The invention further relates to a device comprising one or more of the characterising features described in the description and/or shown in the attached drawings.

The invention further relates to a method comprising one or more of the characterising features described in the description and/or shown in the attached drawings. The various aspects discussed in this patent can be combined in order to provide additional advantages.

Description of the drawings

The invention will be further elucidated referring to an preferred embodiment shown in the drawing wherein shown in:

Fig. la-e a schematic view of the bow coupling system according to the invention during subsequent stages of the method for coupling the manoeuvrable vessel to the floating structure;

fig. 2 a schematic view of a detail of the bow coupling system of fig. la-e;

fig. 3 a schematic view of another detail of the bow coupling system of fig. la-e; fig 4, a schematic view of a detail of a vessel provided with a further embodiment of a coupling system according to the invention, and

fig 5a-5d schematic views of the embodiment of fig. 4 while in use.

Detailed description of embodiments

In the figures la-e a schematic view of the bow coupling system 8 according to the invention during subsequent stages of the method for coupling the manoeuvrable vessel 1 to the floating structure 2. Figure 2 depicts a schematic view of a

manoeuvrable coupling means 6 of the bow coupling system 8. Figure 3 shows a detail of the manoeuvrable coupling means 6. The invention will be further elucidated in more detail referring to the figures.

Fig la-e show the method, or better stills during the method, for coupling a manoeuvrable vessel 1 to a floating structure 2. The method comprises the step providing a pickup system 3. The pickup system 3 is coupled to the floating structure 2 such that the floating structure can be, at least in part, lifted out of the water. A typical floating structure is a floating pipeline for transport of dredge under pressure. The pickup system 3 comprises a float 4. The float 4 serves to provide buoyancy to at least the pickup system 3 itself. In addition, the float 4 enables the pickup system 3 to extend from the water surface such that visibility of the pickup system 3 is facilitated. The method comprises the step providing a manoeuvrable vessel 1 which is typically a hopper dredger type of vessel. The vessel 1 comprises a coupling system 5 for coupling the vessel 1 to the floating structure 2. The coupling system 5 comprising manoeuvrable coupling means 6 on the manoeuvrable vessel 1.

The method comprises the step aiming the manoeuvrable coupling means 6 towards the pickup system 3.

The method comprises the step guiding the manoeuvrable coupling means 6 into float coupling means 7 of the pickup system 3. Where it says "into" this may mean into like in a plug and socket situation however any other suitable engagement will suffice as long as the manoeuvrable coupling means 6 engage the float coupling means 7 in a coupling manner.

The method comprises the step locking the float coupling means 7 with respect to the manoeuvrable coupling means 6 such that a coupling connection between the manoeuvrable vessel 1 and the floating structure 2 is established.

The method comprises the step connecting the floating structure 2 to the coupling vessel 1 for transport of dredge between the vessel 1 and the floating structure 2.

A bow coupling system 8 is shown for connecting a floating structure 2 to the bow 9 of at least one manoeuvrable vessel 1. The bow coupling system 8 comprising a pickup system 3 and a coupling vessel 1. The pickup system 3 comprises a pair of floats 4 for buoyancy of the floating structure 2 or at least the pickup system 3 on a water surface 10. The pickup system 3 comprises a float coupling means 7 connected to the pair of floats 4. The float coupling means 7 extend from the float 4 above the water surface 10. The coupling vessel 1 comprises a manoeuvrable coupling means 6 for engaging the float coupling means 7 of the pickup system 3, such that a coupling connection between the manoeuvrable vessel 1 and the floating structure 2 is obtained. Here, the coupling connection between the vessel 1 and the floating structure is obtained by accommodation of the manoeuvrable coupling means 6 in the float coupling means 7, fig. lb and further.

The floating structure 2 comprises a pickup system 3. The pickup system 3 is suitable for raising at least a part of the floating structure 2 above the water surface 10. Here, the floating structure 2 comprises a floating conduit 13 having a free end 14, and wherein the pickup system is coupled with the free end 14 for raising the free end above the water surface 10. The pickup system is coupled via a pickup line 15 to the floating conduit 13. The pickup line 15 is coupled with the floating pipeline 13 at the free end 14 of the floating pipeline 13. The pickup system 3 comprises an erected elongate float 4 which float 4 extends partly above the water surface 10. The float 4, or here a pair of floats, comprises a float coupling means 7 for cooperation with a vessel coupling means 6 associated with a manoeuvrable vessel 1 which intends to couple with the floating structure 2. Here, the float coupling means 7 is arranged at an upper end of the float 4.

The float 4 comprises a slimline portion 11 beneath the float coupling means 7. In use, the slimline portion 11 is proximate the water surface 10, for decreasing movement of the float 4 in particular under rough sea conditions.

The float 4 comprises orientation means 12 for an operator of the manoeuvrable vessel 1 to facilitate orientation. Here, the orientation means 12 are arranged above the float coupling means 7.

Here, the pickup system 3 comprises a pair of erected elongate floats 4, and the float coupling means 7 and the orientation means 12 extend between the floats 4.

A manoeuvrable vessel 1 is shown, which vessel 1 comprises a coupling system 5 for coupling a vessel 1 to an adjacent floating structure 2 to the vessel 1. The coupling system 5 comprises manoeuvrable coupling means 6 manoeuvrable with respect to the vessel 1 for compensating movement of the float 4 in particular under rough sea conditions. The manoeuvrable coupling means 6 is hingeable between a substantially horizontal position shown in fig. 2 at reference number 6a, and 6b, and a raised position shown in fig. 2 at reference number 6c. In its horizontal position the coupling means 6 is engageable with float coupling means 7 associated with a floating structure 2 the manoeuvrable vessel 1 intends to couple with. Its raised position is for coupling the float 4 with the manoeuvrable vessel 1. Fig. 3 shows the hinging axis 16 the coupling means 6 hinges around between its substantially horizontal position and its raised position. In the raised position of the manoeuvrable coupling means 6, the float 4 is locked in the locking accommodation 18, specifically the float coupling means 7 is locked in the locking accommodation 18. An actuator, like a hydraulic cylinder is coupled with the fixing hole 17 of the manoeuvrable coupling means 6 for hinging the manoeuvrable coupling means 6 between the substantially horizontal position and the raised position. Fig 4 shows a detail of a vessel 1 provided with a further embodiment of a coupling system according to the invention. Fig 5a-5d show the coupling system of fig. 4 while in use.

The coupling device 5 is articulated. The coupling device 5 has a leading coupling device member 6a and a trailing coupling device member 6b.

The leading coupling device member 6a is provided with the coupling means 24 for engaging the float coupling means of the pickup system 3.

The trailing coupling device member 6b is configured to be supported by the vessel 1 in a hingeable manner. The trailing coupling device member 6b is hingeable with respect to the vessel 1 around hinging axis 16a by a hydraulic cylinder 23. The trailing coupling device member 6b is configured to be supported by the vessel 1 in a hingeable manner proximate the conduit coupling means 20, opposite its respective coupling end.

The trailing coupling device member 6b is hingeably coupled with the leading coupling device member 6a. The trailing coupling device member 6b is hingeably coupled with the leading coupling device member 6a at their respective coupling ends. The trailing coupling device member 6b is hingeably coupled with the leading coupling device member 6a and the members are mutually hingeable around hinging axis 19. The trailing coupling device member 6b is hingeably with respect to the leading coupling device member 6a by a hydraulic cylinder 22.

The leading coupling device member 6a is provided with a coupling means 24. The coupling means 24 are situated at a free end of the leading coupling device member 6a opposite its respective coupling end.

The trailing coupling device member 6b is provided with a conduit coupling means 20. The conduit coupling means 20 are situated at a free end of the trailing coupling device member 6b opposite its respective coupling end. The conduit coupling means 20 is configured to engage the conduit at its upper head 27, as can be seen in fig. 5c. The leading coupling device member 6a and the trailing coupling device member 6b are mutually hingeable between a retracted position, as shown in fig. 5a, and a extended position, as shown in fig. 5b, of the coupling device 5. The coupling means 24 and the conduit coupling means 20 are arranged with respect to the coupling device 5 such that, in the extended position of the coupling device the coupling means 24 and the conduit coupling means 20 are remote with respect to each other and the coupling means 24 extend toward the water surface 21, The coupling means 24 and the conduit coupling means 20 are arranged with respect to the coupling device 5 such that in the retracted position of the coupling device 5 the coupling means 24 and the conduit coupling means 20 are about vertically aligned.

In use, initially the coupling device 5 is in its retracted position, fig 5a. Then, the coupling means 24 reach toward the pick up system 3 at the waterline 21, fig. 5b, and engages a collar 26 of the pick up system 3. Subsequently, the coupling device 5 lifts the pick-up system 3 in unity with the conduit, thereafter the conduit coupling means 20 engages the conduit proximate its head 27, fig. 5b, 5c. Next, a slurry intake 25 contacts the head 27 for transport of fluid under pressure.

It will also be obvious after the above description and drawings are included to illustrate some embodiments of the invention, and not to limit the scope of protection. Starting from this disclosure, many more embodiments will be evident to a skilled person which are within the scope of protection as defined in the claims and which are obvious combinations of prior art techniques and the disclosure of this patent.