WO2000066422A1

WO2000066422A1 - Method and device for coupling a vessel to another vessel or to a structure

Info

Publication number: WO2000066422A1
Application number: PCT/NO2000/000122
Authority: WO
Inventors: Njål UNDERHAUG; Ola Ravndal; Svein Inge Eide
Original assignee: Navion Asa
Priority date: 1999-04-29
Filing date: 2000-04-13
Publication date: 2000-11-09
Also published as: NO992053A; RU2245276C2; FI117195B; KR100616112B1; AU3988800A; NO992053D0; KR20020000881A; JP2002542990A; NO308591B1; CA2371054A1; FI20012070A

Abstract

A method and device for coupling a vessel with a structure or another vessel, typically for coupling a powered propelling vessel with a barge, in which at least one coupling half on one of the vessels is brought together with and releasably coupled to a complementary coupling half on the other vessel. The coupling half is made to follow the movements of the complementary coupling half by subjecting the movable coupling half to a limited force directed towards the complementary coupling half, in a way such that the movable coupling half yields to a greater contact force between the coupling halves, whereupon the movable coupling half is still subjected to a limited force that is varied in opposite phase to the intermovement of the vessels, and which is increased until the intermovement of the vessels has been reduced to an acceptable magnitude, or possibly to zero.

Description

METHOD AND DEVICE FOR COUPLING A VESSEL TO ANOTHER VESSEL OR TO A STRUCTURE

The invention regards a method and a device for coupling a vessel to another vessel or to a structure, such as coupling a powered vessel to a barge.

Barges without costly propulsion means and associated crew contribute towards reducing freight charges by one powered vessel operating several barges.

Barges may be towed in calm waters, however in choppy seas a long towline is required thus making the tow difficult to steer. It has proven to be expedient to couple up the powered vessel and the barge in a manner so as to make the powered vessel form a more or less rigid extension of the barge and allow it to push the barge in front.

In particular, the invention aims at a method and a device for such coupling of a barge and a powered vessel, hereinafter called a propelling vessel. Several solutions for such coupling up of a barge and a propelling vessel are known. Typically, the propelling vessel and barge are provided with complementary coupling halves that are brought together and form a coupling, whereupon a locking device is activated in order to ensure that the coupling is maintained. A common feature of known solutions is that the aft-end of the barge is provided with an opening or a booth where the propelling vessel is run in bow-first and then coupled to the barge. The propelling vessel is typically provided with coupling halves on the bow and on or at either side. The complementary coupling halves of the barge are correspondingly placed at the innermost end and in the middle of the booth for coupling to the corresponding coupling half on the bow of the propelling vessel, and on either side of the booth for coupling to the corresponding coupling half on the side of the propelling vessel. The length and mass of the barge is great when compared to the propelling vessel, and in a seaway, the barge will move in a different manner from the propelling vessel. It is therefore essential when linking up to be able to guide coupling halves together that move with respect to each other.

Waves cause the propelling vessel to heave, i.e. move vertically, relative to the barge. Furthermore, the waves cause yawing, i.e. course deviation between the longitudinal directions of the propelling vessel and the barge. Rolling about the longitudinal axis of the propelling vessel and tilting about the transversal axis of the barge result in the deck area of the propelling vessel rarely being parallel with that of the barge.

In addition, the waves may cause the propelling vessel to hunt, i.e. it goes through a horizontal back-and-forth motion relative to the barge. When the propelling vessel is in the booth, or on its way into the booth, hunting is primarily noticed in the longitudinal direction of the propelling vessel. Hunting may make it difficult to position the propelling vessel in the service position in the longitudinal direction of the barge. This leads to said locking device being activated while there is relative movement between the propelling vessel and the barge, something which may cause damage to the locking device. Solutions are known in which the propelling vessel is manoeuvred to a position where it rests against the barge, and where this position is also the service position. This makes it easier to avoid damage to the locking device but places considerably greater demands on the accuracy of the mechanical design, so as to allow for example a locking pin to meet a hole and give close to play-free locking.

The draught of the barge depends on the cargo. In some known solutions for coupling of barges and propelling vessels, the vertical position of the propelling vessel relative to the barge is determined by the coupling device. The propelling vessel will normally tolerate less variation in draught than the barge. Thus a specific vertical position for the propelling vessel limits the permissible variations in the draught of the barge.

Solutions are known in which the propelling vessel may be coupled to the barge in several vertical positions. If the draught of the barge changes radically while the propelling vessel is coupled up, the propelling vessel may be uncoupled from the barge and then re-coupled in a different vertical position. A known solution for this consists in the propelling vessel being provided with projecting coupling halves which, upon the propelling vessel being run into the booth, are guided into grooves in the side wall of the booth, and possibly also in the end wall of the booth. By having several parallel, vertically spaced grooves, the projecting coupling halves on the propelling vessel may be guided into grooves that are appropriate for the draught of the barge and the propelling vessel. Fine adjustment is achieved by changing the ballast of the propelling vessel. In order to facilitate finding the grooves when the propelling vessel is run into the booth, it is known to provide the grooves with a diverging portion at the aft-end of the booth, in a way such that the projecting coupling halves of the propelling vessel may be guided into the groove.

It is a problem with said solution that the rolling of the propelling vessel may easily cause the projecting coupling half on one side of the propelling vessel to engage a groove in a different vertical position from the one engaged by the projecting coupling half on the opposite side of the propelling vessel. The propelling vessel will then take a list.

This may be avoided by having only one groove in each of the side walls of the booth, and arranging each groove in a vertically moveable slide. Prior to coupling, the slide is positioned so as to make the vertical position of the groove match the draught of the barge and the propelling vessel, whereupon each slide is locked in the selected vertical position and the propelling vessel is run into the booth.

In a seaway, the projecting coupling halves of the vessel and the complementary grooves in the barge are subjected to great strain due to the intermovement between the vessels. When the propelling vessel is positioned in the booth, a locking device is normally activated in order to ensure that the propelling vessel does not shift in relation to the barge. The locking device can consist of movable locking pins that are associated with or form part of the projecting coupling halves of the propelling vessel. The locking pins are typically moved to an ac-ive position, in which they engage holes in the side face of the booth, e.g. in said grooves.

In a main group of known solutions for coupling a propelling vessel to a barge, a rigid coupling is formed, in a manner such that the propelling vessel and the barge in effect behave as one vessel. Some embodiments are such that the propelling vessel can only assume a fixed vertical position relative to the barge. A disadvantage of these is the fact that they do not allow much in the way of variation in the draught of the barge while the propelling vessel is coupled to the barge. Other embodiments allow the propelling vessel to be coupled to the barge in one of several possible vertical positions. Upon a change in the draught of the barge, the coupling can be released and the propelling vessel then coupled to the barge in another vertical position. However, performing such recoupling in rough seas is not particularly desirable, as it is complicated, time consuming and risky.

A group of rigid couplings in said main group comprises a booth at the end of the barge, the booth being provided with a bottom plate or other plates on which the propelling vessel rests. The propelling vessel is run into the booth carrying little ballast. By filling water in the ballast tanks, the propelling vessel is lowered to rest against the bottom plate or other plates in or by the booth. The booth may be provided with coupling halves designed to engage complementary coupling halves in the propelling vessel, so as to make the propelling vessel steady in the booth. Obviously it is very difficult, even impossible, to set the propelling vessel down onto coupling halves on the barge in this manner in a rough sea. And of course a big wave may lift the propelling vessel off the barge coupling halves. Examples of this type of coupling are known from, inter alia, US 3,345,970, US 3,610,196, US 4,048,941.

A similar type of rigid couplings comprises upper abutment areas that prevent a wave from lifting the propelling vessel off the barge coupling halves. US 3,842,783 shows a booth with a bottom plate and an upper abutment area that projects inward over the fore deck of the propelling vessel when it is positioned in the booth. The propelling vessel is trimmed to the correct draught with respect to the barge before being run into the booth. The propelling vessel and the abutment areas in the booth are conical, such that the propelling vessel is wedged into a stable position. It is difficult to run the propelling vessel into the booth in a rough sea, and powerful impacts between the vessels may easily occur.

In US 4,000,714, a booth is shown as having a bottom plate and areas that project inward across part of the deck of the propelling vessel when it is positioned in the booth. The propelling vessel is trimmed so as to allow it to be run into the booth with a slight clearance to the bottom plate and clearance between the deck and said abutment areas. Inflatable fenders placed between the propelling vessel and the booth make sure the propelling vessel is stable. Also in this case, it is difficult to run the propelling vessel into position in the booth in a rough sea.

Another known type of rigid coupling is based on the coupling halves on either side of the propelling vessel, and often also in the bow of this, being run into engagement with complementary coupling halves in a booth at the end of a barge. The coupling halves can be said to form tongue and groove, quite possibly in the form of conical coupling halves that also project from the propelling vessel, and complementary coupling halves on the barge in the form of conical grooves or indentations that are intended to receive the coupling halves when the propelling vessel is run into the booth. The coupling halves are conical in order to reduce the requirements for position accuracy early in the coupling stage. As the propelling vessel gets further and further into the booth, the propelling vessel is guided towards a final service position by the conical coupling halves. Examples of such couplings are to be found, inter alia, in US 4,013,032, US 4,356,784 and GB 2053807. This type of coupling is difficult to link up in a rough sea.

Another type of rigid coupling consists in one of the vessels being provided with moveable pin-like and more or less conical means that are inserted into complementary holes or recesses in the other vessel. Examples of such couplings are known from, inter alia, US 3,910,219 and NO 174702. These are also difficult to link up in a rough sea, and like the aforementioned rigid couplings, they are not really suitable in the case of variations in the draught of the barge.

In order to make rigid couplings more suitable for variations in the draught of the barge, it is known to provide the vessels with coupling halves that can be connected in several positions. It is for instance known to provide one of the vessels with projecting wedges or moveable pin-like, more or less conical means, and the other vessel with several complementary grooves, holes, indentations or recesses.

Examples of this can be found in, inter alia, US 3,910,219, US 4,013,032 and US 5,050,522.

US 3,512,495 shows a propelling vessel with topshaped coupling halves that are pushed out from the sides of the propelling vessel and into holes in complementary coupling halves in the side walls of a booth on a barge. Each of the complementary coupling halves is fitted in a slide that can be moved vertically in a groove in the booth. Those coupling halves may thus be set to the desired vertical position, thereby compensating for the draught of the barge varying with the cargo. The complementary coupling halves are clamped between two flexible clamps in the slide to achieve a flexible coupling.

In another main group of known solutions, a moveable or articulated coupling is formed to allow the propelling vessel to move with respect to the barge in a seaway. In some known solutions, a coupled propelling vessel can tilt about a transversal axis, in other known solutions, propelling vessels can move vertically with respect to the barge, and other solutions again have the propelling vessel rotating about several axes and being moved relative to the barge. In practice, it is desirable that the movements be limited, and that there is a rigid or near-rigid coupling in at least one direction, for example such that the propelling vessel cannot roll, move in the longitudinal direction, or heave relative to the barge. From US 3,605,675, a coupling is known where one of the coupling halves comprises a vertically moveable boom across a booth at the aft-end of the barge. The boom is provided with a slide at either end, which slide is designed to run in a vertical groove. Each slide is suspended at one end of a line that runs over a pulley, and which at the other end is provided with a counterweight lead in order to balance the boom in terms of weight. The boom is raised to an upper position, and the propelling vessel is run into the booth with the fore deck underneath the boom. Complementary coupling halves are arranged on the fore deck, which coupling halves are designed to be closed rotatably around the boom in order to couple the propelling vessel to the boom and thereby to the barge. A winch on the fore deck is connected to a lug in the middle of the boom, and pulls this down towards the fore deck until it abuts said complementary coupling halves, which are then closed around the boom. Each of said slides is provided with a braking device designed to act on the side walls in the groove, thereby braking the vertical movement of the slide, and thereby that of the propelling vessel, with respect to the barge. The winch must be manually connected to the boom, and this is an operation that is difficult to perform in a rough sea. Naturally, it is also dangerous. In addition, rollers are provided on either side, which rollers are designed to be pushed out from the propelling vessel until they abut the side walls of the booth. The rollers allow the propelling vessel to move vertically, while at the same time centering the propelling vessel in the booth.

From US 3,844,245, a coupling is known where conical brake blocks on either side of a propelling vessel are designed to be pushed out sideways from the propelling vessel and into complementary vertical grooves in either side of a booth at the end of a barge. The grooves have a truncated, V-shaped cross section with the opening facing the booth, such that there is no requirement for accurate longitudinal positioning of the propelling vessel in order to find the groove with the conical brake blocks. The grooves are placed in such a manner that the propelling vessel can be run with the bow into engagement with the forward edge of the booth, while the centre of the brake blocks is located slightly further forward than the central vertical axis of the grooves . When the conical brake blocks are pushed into the V-shaped grooves, sloping contacting surfaces cause the propelling vessel to be pushed astern relative to the barge, to a service position in which there is clearance between the bow of the propelling vessel and the barge. It is however difficult to stabilise the propelling vessel by use of this known solution. One reason for this is that the pushing power that acts on the brake blocks simultaneously has a strong effect on the longitudinal movement, rolling and vertical movement of the propelling vessel.

US 4,407,214 shows a coupling where a propelling vessel is coupled to a barge via opposing arms designed to prevent the propelling vessel from rolling relative to the barge, without restricting heave and tilt to any great extent. The opposing arms are rotatably connected to the propelling vessel through shafts or pins that are inserted into holes in coupling halves on the propelling vessel. Thus linking up is difficult to perform in a rough sea.

In addition, couplings are known that allow controlled sideways movement of the propelling vessel relative to the barge, in a manner such that a directional deviation between the propelling vessel and the barge is achieved, in order to give the vessels better overall steering characteristics. US 5,687,668 shows an example of such a coupling.

It is of current interest to use barges in offshore operations, for example in connection with the recovery of oil and gas. Offshore installations then constitute an end station, where the propelling vessel and the barge are coupled and uncoupled. Coupling up will therefore take place in open seas. Although some of the known solutions for coupling up a propelling vessel and a barge are capable of accommodating small relative movements between the propelling vessel and the barge, they are unsuitable for choppy seas.

It is also of current interest to be able to connect larger vessels together, where even a moderate seaway imparts such great momentum to the vessels that the connecting is difficult to solve using prior art.

It is an object of the invention to provide a method and a device suitable for coupling up a propelling vessel and a barge in choppy seas.

It is a further object that the invention be usable for connecting larger vessels together.

The objects are achieved through the characteristics that appear from the following description and the subsequent claims.

According to the method of the invention, coupling between vessels or between a vessel and a structure is carried out in several stages. The following refers to coupling of a propelling vessel and a barge, where at least one coupling half on one of the vessels is brought together with and releasably coupled with a complementary coupling half on the other vessel, thereby forming a releasable coupling between the vessels.

A coupling according to the invention is characterised by the following steps:

A movable coupling half on one of the vessels,

- which immediately upon a coupling moment, in which contact with a corresponding, complementary coupling half on the other vessel takes place,

is made to follow the movements of the complementary coupling half

- by applying a limited force to the movable coupling half, which force is directed towards the complementary coupling half,

- in a way such that the movable coupling half yields to a greater contact force between the coupling halves,

- whereupon a limited force is still applied to the movable coupling half,

- which force varies in opposite phase with the intermovement of the vessels and is increased until the intermovement of the vessels is reduced to an acceptable magnitude, or possibly to zero.

The propelling vessel can, in a way that is known per se, be led into a booth at the end of the barge and kept in contact with the barge by use of the propulsion engine of the propelling vessel. By so doing, the movement of the propelling vessel relative to the barge can be reduced from six degrees of freedom with translational motion along and rotation about the three main axis of the propelling vessel, one longitudinal axis, one transverse axis and one axis perpendicular to the deck area, to three degrees of freedom, viz. translational movement along an axis perpendicular to the deck area of the barge and rotation about the longitudinal and transverse axis of the propelling vessel.

In order to bring the propelling vessel into the correct position in the longitudinal direction before bringing the coupling halves into engagement, the propelling vessel may advantageously be kept in contact with the barge through forward engine admission to a position further ahead than the coupling position, whereupon a reversing force e.g. from an actuator, which force acts between the propelling vessel and the barge, pushes the propelling vessel astern relative to the barge, against the force of the propulsion engine of the propelling vessel, and into the coupling position.

The following describes the invention; first the principles of it and then by use of examples of embodiments, while referring to the attached drawings, in which: Figure 1 schematically shows six steps in a coupling sequence for single-acting coupling of a coupling means to a floating body through the use of an actuator;

Figure 2 shows a simple hydraulic connection diagram for the actuator of Figure 1;

Figure 3 schematically shows six steps in a coupling sequence for double-acting coupling and dampening;

Figure 4 shows a front view of three steps in a coupling sequence for coupling of coupling halves, on an enlarged scale;

Figure 5 shows a side view of a coupling as shown in Figure 4, in the connected position;

Figure 6 schematically shows a top view of a propelling vessel in a booth at the end of a barge;

Figure 7 schematically shows six steps in a coupling sequence for coupling halves associated with propelling vessel and barge as shown in Figure 6 ;

Figure 8 shows a perspective view of a propelling vessel on its way into a booth at the end of a barge, either side of which booth is provided with a vertically moveable coupling half;

Figure 9 shows a perspective, enlarged view of coupling halves for the propelling vessel and the barge of Figure 8; Figure 10 shows a perspective view of coupling halves where cogwheels mesh with a toothed rack;

Figure 11 shows a perspective view of coupling halves with dampening along two axis;

Figure 12 shows a horizontal section through one of the coupling halves in Figure 11, on an enlarged scale;

Figure 13 shows a perspective view of part of a barge stern with manipulator arms that are ready to be coupled to a propelling vessel;

Figure 14 shows a perspective view of a propelling vessel that is coupled to a moveable transverse boom at the end of a barge by a transverse groove in the bow;

Figure 15 shows a perspective view of a propelling vessel that is coupled to a moveable transverse boom at the end of a barge by a transverse groove in the fore deck;

Figure 16 shows a perspective view of a propelling vessel on its way into a booth at the end of a barge, where the booth is provided with transverse straps.

In Figure 1, reference number 1 indicates an actuator in the form of a hydraulic cylinder provided with a hydraulic power source (not shown) and a control system (not shown) . The actuator 1 is designed to move a coupling half in the form of contacting means 2 vertically over a floating body 3 that is floating in water 4, and which is subjected to vertical movement by waves in the water 4. The floating body 3 symbolises a propelling vessel, and it is intended that the actuator 1 be associated with a barge (not shown) to which the propelling vessel is to be connected.

Figure 1 shows the floating body 3 in six vertical positions in a sequence indicated by the letters A-F. In position A, the contacting means 2 is in the initial position a distance above the floating body 3, which is about to be lifted by a wave. The actuator 1 is made to lower the contacting means 2 into contact with the floating body, preferably as the floating body 3 reaches an upper position B at the crest of a wave, as shown for position C.

The downward acting force applied by the actuator 1 to the contacting means 2 is very small, and does not have any significant downward effect on the floating body 3. The downward acting force must nevertheless be great enough for the contacting means 2 to follow the floating body 3 and be kept in contact with this during the subsequent downward movement of the floating body 3 towards the next trough of the waves, as shown for position D. Thus the actuator 1 initially yields a force that acts in the same direction as the natural movement of the floating body 3.

As the floating body 3 reaches a lower position E in a trough and reverts to an upward movement, the force of the actuator 1 is still acting downward. The force from the actuator 1 is thereby directed against the natural movement of the floating body 3. The upward movement of the floating body 3 is thus retarded by the force of the actuator 1, and the floating body 3 does not rise to position B, but comes to a stop at an upper position F. In an upper position F, which is lower than the natural upper position B, the freeboard of the floating body 3 will naturally be less than the natural freeboard of the floating body 3.

As the waves cause the movement of the floating body 3 to again change to the downward direction, the downward acting force of the actuator 1 is readjusted to a smaller magnitude that is great enough to keep the contacting means 2 in contact with the floating body 3 without contributing significantly towards the downward movement of the floating body 3. Consequently, the floating body 3 will swing between a lower position E and an upper position F. The lower position E coincides with the natural lower position of the floating body 3, while- the upper position F is lower -than the natural upper position B of the floating body 3.

By gradually increasing the downward acting force of the actuator 1 when the floating body is on the way up, the distance from position E to position F can be gradually reduced. If the freeboard of the floating body 3 allows it, the force of the actuator 1 may be increased until the upper position F of the floating body 3 coincides with the natural lower position E of the floating body, and even lower than this. The force of the actuator 1 is adjusted as required, so as to position the floating body 3 to the desired freeboard.

Variations in the distance between the actuator 1 and calm water 4 can easily be offset by the actuator. If the actuator 1 is on a barge, the distance between the actuator 1 and calm water 4 will vary according to the cargo of the barge. If the actuator is installed on a fixed structure, the distance between the actuator 1 and calm water 4 vary with the tide. A hydraulic system for the actuator 1 may be realised in a number of ways that are known to those skilled in the art. Referring to Figure 2, there is shown a simplified connection diagram for a hydraulic coupling that is easy to implement. In Figure 2, the actuator 1 is shown as a single-acting hydraulic cylinder in which the contacting means 2 is attached to the free end of a piston rod 5 associated with a piston 6 in the actuator 1. A spring 7 acting on the piston rod side of the piston 6 retains the piston 6, and thereby the contacting means 2, in the initial position.

The actuator is connected to a pressure pipe 8 that is connected to the delivery side of a pump 10 through a check valve 9, which pump 10 draws liquid from a tank 11. The pump pressure can be selected in a known manner by using a first adjustable pressure controller 12, and a pressure accumulator 13 contributes in a known manner towards balancing the pressure. A return line 14 for hydraulic fluid is connected between the actuator 1 and the tank 11, the check valve 9 preventing liquid from returning via the pump 10. A second pressure controller 15 and an adjustable flow resistance in the form of an adjustable throttle 16 are provided in the return line 14.

The downward acting force exerted by the actuator 1 when the contacting means 2 follows the downward moving floating body 3, as explained in connection with Figure 1, is determined by the pressure regulator 12. The smallest downward acting force, which exerted by the actuator 1 when the floating body 3 rises, is determined by the second pressure controller 15, and the greatest downward acting force is determined partly by the throttle 16 setting and partly by the velocity of the floating body 3. In order to avoid an impact at the moment of coupling, when the contacting means 2 is brought into contact with the floating body 3, the coupling should take place when the floating body 3 is near its upper natural position B in Figure 1. If the total mass of the contacting means 2 and the associated moveable parts of the actuator 1 is small, the contacting means 2 may be released in free fall into contact with the floating body 3.

In a more developed embodiment, the actuator 1 may form part of a servo system (not shown) designed to move the contacting means 2 in time with the floating body 3 and at an adjustable distance from it. By gradually reducing the distance between the contacting means 2 and the floating body 3, the servo system can contribute towards bringing the contacting means 2 into contact with the floating body 3 without impact occurring, independently of the velocity of the floating body 3 and its position between the upper position B and the lower position E.

The contacting means 2 may be seen as a first coupling half, where the floating body 3, or part of it, constitutes a second, complementary coupling half. Together, they form a coupling that is single-acting in the sense that it only transfers a compressive force. It will easily be appreciated that the first coupling half, the contacting means 2, may be provided with one or several pins that project down into complementary holes in the second coupling half; in this manner the coupling may transfer horizontal forces and retain the floating body 3 sideways.

Figure 3 shows approximately the same as Figure 1, but where the actuator 1 is designed to move a coupling half 17 and the floating body 3 is provided with a complementary coupling half 18. The coupling half 17 and the complementary coupling half 18 are designed to be connected to each other in a releasable manner. In the coupled condition, the coupling half 17 and the complementary coupling half 18 form a coupling that can absorb vertical force in both directions. Thus is achieved a double-acting dampening of the movements of the floating body 3, as is apparent from the following.

Coupling is performed by lowering the coupling half 17 and bringing it into contact with the complementary coupling half 18 on the floating body 3, e.g. when the floating body 3 is in an upper position B/C such as shown in Figure 3. Obviously, use can also be made of a servo system, as described. When contact between the coupling half 17 and the complementary coupling half 18 has been established, the coupling between the two is activated.

As the downward movement of the floating body 3 begins, the actuator 1 is made to exert an opposite force, i.e. an upward acting force that is transferred to the floating body 3 via the coupling halves 17, 18. The upward acting force that acts while the floating body 3 is on its way down toward a trough, see Figure 3, position D, contributes towards the floating body 3 reaching a lower position E that is higher than the natural lower position of the floating body 3. The floating body 3 will have a greater freeboard at the lower position E than the natural freeboard.

When next a wave acts to lift the floating body 3, the actuator 1 is caused to exert an opposite, i.e. a downward acting force. As explained previously in connection with Figure 1 , this force contributes towards the upward movement of the floating body 3 being limited to an upper position F that is lower than the natural upper position of the floating body 3. By increasing the actuator force from a small initial value, the movement of the floating body 3 can be gradually dampened, so as to gradually reduce the distance between the lower position E and an upper position F of the floating body 3. The actuator force may, if so desired, be increased to a value where the floating body 3 is kept still in a position between its natural upper and natural lower positions.

Figure 4 shows an example of a double-acting coupling with a coupling half 19 that is designed to be moved vertically by a piston rod 20 in an actuator (not shown), and a complementary coupling half 21 arranged on a floating body 22. The complementary coupling half 21 comprises a cylindrical bolt 23 that is arranged a distance above the surface of the floating body 22 by use of a spacer 24. The coupling half 19 comprises a head 25 with a downward facing opening 26 that is designed to receive the bolt 23. On either side of the opening 26 is fitted rotatable detent latches 27 and 28 respectively, which in the initial position rest on their respective end stops 29, 30. In the initial position, the detent latches 27, 28 project into the opening 26, such that the distance between the detent latches 27, 28 is less than the diameter of the bolt 23.

Prior to coupling, the relative positions of the coupling halves 19, 21 are as shown at the position marked with Roman numeral I in Figure 4. When coupling, the coupling half 19 is brought down, and the detent latches 27, 28 swing upward and give way to the bolt 23 as shown in position marked with Roman numeral II. When the bolt 23 is in place in the opening 26, the detent latches 27, 28 return to the initial position and absorb tension between the coupling halves 19, 21, see position marked with Roman numeral III in Figure 4.

The coupling between the coupling halves 19, 21 may be released in several ways. The detent latches 27, 28 can be rotated upward to a position as shown in position II by use of actuators (not shown). Another method of release is illustrated in Figure 5, in which the bolt has been made longitudinally displaceable and is associated with a piston rod 31 in an actuator 32. The coupling between the coupling halves 19, 21 is released by pulling the bolt 23 out of the coupling half 19 by use of the actuator 32.

It will easily be appreciated that the single-acting and double-acting principles of the invention can be applied to other directions of movement than the vertical direction. By joining several actuators acting in different directions, and thus applying the principle of the invention several times, coupling and dampening of movements that consist of several directional components may be accomplished.

It will also easily be appreciated that the single-acting and double-acting principles of the invention may be applied in combination with known principles for coupling and dampening of the movements of a floating body 3. When a propelling vessel is to be coupled to a barge, it may for instance be of interest to couple transversely in a known manner by placing the propelling vessel in a booth at the end of a barge, and couple vertically and longitudinally by applying the invention.

Figure 6 shows, schematically and seen from above, a propelling vessel 33 that has been run into a booth 34 at the end of a barge 35. A vertical groove 36 is provided in the starboard side wall of the booth 34, which groove has sloping side walls to make the cross section form a truncated V- shape. A corresponding opposite V-shaped groove 37 is provided in the port side wall of the booth 34.

The propelling vessel 33 is provided with a starboard coupling half 38 that is associated with a starboard actuator 39. The outside of the coupling half 38 has a V-shape and is designed to fit in the groove 36. The actuator 39 is designed to be able to push the coupling half 38 in the transverse direction of the propelling vessel 33, out from the propelling vessel 33 and into the groove 36. In the same way, the propelling vessel 33 is provided with a port coupling half 40 that is associated with a port actuator 41.

Coupling of the propelling vessel 33 to the barge 35 is described with reference to Figure 7, which shows the coupling halves 38, 40 and associated actuators 39, 41 in six positions, marked A-F, relative to the grooves 36, 37. Position A corresponds to the position of the propelling vessel 33 in Figure 6. The actuators 39, 41 are made to push the coupling halves 38, 40 out from the sides of the propelling vessel and into the grooves 36, 37, as shown for position B in Figure 7. At the moment of coupling, contact is made between the sloping surfaces of the coupling halves 38, 40 and the complementary sloping surfaces of the grooves 36, 37.

The pushing power of the actuators 39, 41 must be sufficient to keep the sloping surface of the coupling halves 38, 40 in contact with the complementary sloping surface of the grooves 36, 37 in the event that the propelling vessel moves astern to a position C and D in Figure 7.

As the propelling vessel is moved further astern to position E, the contacting force between coupling half 38, 40 and groove 36, 37 pushes against the force from the associated actuator 39, 41.

By increasing the actuator force in the same way as explained in connection with Figure 1 , the movement of the coupling halves 38, 40 may be dampened so as to make the propelling vessel oscillate between a forward position C and an aft position E. If the actuator force is increased further, the longitudinal movements of the propelling vessel may be dampened completely and the propelling vessel kept still in a position F in Figure 7, where each coupling half 38, 40 is centered in the associated, complementary groove 36, 37.

It will easily be appreciated that the propelling vessel 33 in Figure 6 may, in addition to the longitudinal and sideways coupling shown, be coupled to the barge 35 in the vertical direction in a manner such as described in connection with Figure 1 or Figure 3. For such vertical coupling, a coupling half (not shown) may be provided in each groove 36, 37, which coupling halves are vertically moveable and each of which is coupled to a complementary coupling half (not shown) on the top of the corresponding coupling half 38, 40. This will be apparent from a more detailed example of an embodiment.

The propelling vessel 33 is uncoupled from the barge 35 by moving the coupling halves 38, 40 back to the initial position as shown in Figure 6. Any double-acting couplings as described in connection with Figure 3 are designed in a manner such that the coupling may be released e.g. by use of an actuated mechanism. An example of such a mechanism will be seen from a more detailed example of an embodiment.

Referring to Figure 8, a propelling vessel 42 is on its way into a booth 43 at the end of a barge 44. In each of the side walls of the booth 43 is provided a vertical groove 45 that has been extended upwards by use of profiled vertical rail

46. A coupling half 47 is provided in each groove 45, which coupling half is designed to be displaceable in the groove 45 by use of a actuator 48.

Either side of the propelling vessel 42 is provided with a projecting, complementary coupling half 49 that is associated with an actuator (not shown). Figure 8 shows the starboard complementary coupling half 49 only. By using said actuators (not shown), the complementary coupling halves 49 may be pulled in towards the propelling vessel 42 in a way so as to let the propelling vessel pass between the coupling halves

47. By using said actuators (not shown), each complementary coupling half 49 may be pushed out from the propelling vessel 42 and into the grooves 45 when the propelling vessel is in place in the booth 43.

When the propelling vessel 42 is to be coupled to the barge 44, the propelling vessel 42 is run into the booth 43 with the complementary coupling halves 49 retracted, and while the coupling halves 47 are in an upper initial position in the grooves 45. The position of the propelling vessel 42 in the booth 43 is adjusted so as to align the complementary coupling halves 49 with the grooves 45. Advantageously, the propelling vessel 42 is equipped with expandable fenders 50 that can be used for fine adjustment of the position of the propelling vessel 42 in the booth 43.

Each of the complementary coupling halves 49 is brought out from the side of the propelling vessel 42 and into the corresponding groove 45 in the booth 43, see Figure 9. The coupling half 47 is provided with an opening 51 that faces downwards, which opening fits the projecting complementary coupling half 49, which is shaped as a bolt. A rotatable detent latch 52 is provided in the opening 51, which latch is designed to catch underneath the complementary coupling half 49 in the same manner as previously explained in connection with Figure 4.

The coupling half 47 is lowered into contact with the complementary coupling half 49 by means of the actuator 48, in a manner such that the detent latch 52 catches underneath the complementary coupling half 49. This is done while the actuator 48 is set to exert limited and relatively little force. The motion of the propelling vessel 42 will thus lead to the force of the actuator 48 being overcome, so as to force the coupling half 47 to follow the vertical movements of the propelling vessel 42 and the complementary coupling half 49. The actuator force is then gradually increased, so as to gradually dampen and possibly halt the vertical movements of the propelling vessel 42.

Figure 10 shows a moveable coupling half 53 designed to be pushed out from the side of a propelling vessel (not shown) and into contact with a complementary coupling half 54 that comprises a vertical groove 55 in the side wall of a booth (not shown) . The groove 55 has got sloping side walls and forms a truncated V-shape as explained in connection with Figure 6. The coupling half 53 is designed to be pushed along an axis 56 of said actuator, and can in addition be rotated about the same axis.

The propelling vessel is equipped with a coupling half 53 on either side, and possibly also in the bow. Correspondingly, the booth on the barge has a groove 55 in either side, and possibly also a groove at the forward end for receiving a coupling half 53 in the bow of the propelling vessel. Figure 10 shows coupling halves 53, 54 for one side of the propelling vessel/booth only.

The coupling half 53 is shaped so as to fit the V-shape of the groove 55, in the same way as explained in connection with Figure 6. The coupling half is equipped with at least one cogwheel 57 designed to mesh with a complementary toothed rack 58 that runs along the bottom of the groove 55. Each cogwheel 57 is associated with an actuator (not shown) that is set so as to be able to rotate the cogwheel 57 and apply an adjustable torque to this. Before connecting the propelling vessel to the barge, the torque is set to a very low value. The coupling half 53 is guided into the groove 55 to make each cogwheel 57 mesh with the toothed rack 58. Vertical wave forces that act on the propelling vessel overcome the actuator force acting between the cogwheel 57 and the toothed rack 58. Thus the propelling vessel moves vertically while each cogwheel 57 rolls along the toothed rack 58. The actuator force is then gradually increased, in order to apply a gradually increasing torque to each cogwheel 57, such that the vertical movements of the propelling vessel are gradually reduced to an acceptable magnitude, or possibly reduced all the way to zero. As explained previously, the actuator force may be a function of the vertical velocity of the propelling vessel. The propelling vessel is uncoupled from the barge by pulling each coupling half 53 out of the groove 55.

The rolling motion of the propelling vessel involves that the coupling halves of the propelling vessel must be able to slide along the grooves. It must also be possible to push the coupling halves of the propelling vessel out from the sides of the vessel to a greater or lesser extent, in order to compensate for the variations in list that result from the rolling motion.

A factor that has gone unrecognised in prior art is the fact that the pitch angle of the propelling vessel is seldom the same as the pitch angle of the barge, and in a seaway, the pitch angle deviation varies continuously. With pitch angle is meant the angle between the longitudinal axis of a vessel and the horizontal plane. During rolling, the coupling halves on each side of the propelling vessel describe a path in a plane that is perpendicular to the longitudinal axis of the propelling vessel, but which is rarely perpendicular to the longitudinal axis of the barge. This leads to that coupling halves and grooves must be designed to absorb great forces in the longitudinal direction of the barge when the propelling vessel rolls.

The movement of the coupling halves in the longitudinal direction of the barge may be absorbed and dampened by use of coupling halves comprising a V-shaped groove in accordance with the principle described in connection with Figure 6 and Figure 7. Another embodiment is apparent from Figure 11, in which a first coupling half 59 is designed to be pushed out from or in towards the side of a propelling vessel (not shown) along a first axis 60 that is essentially oriented abeam of the propelling vessel. Movement along first axis 60 is performed by a first actuator 61 comprising a piston rod 62. The coupling half 59 is also designed to rotate about first axis 60 in order to accommodate changes in the pitch angle of the propelling vessel or the barge.

The coupling half 59 is provided with a top 63 that may be pushed along a second axis 64 across first axis 60, i.e. essentially parallel with the longitudinal axis of the propelling vessel, through use of a second actuator 65. The top 63 is further designed to be rotated through a limited angle about second axis 64 in case of the propelling vessel taking a list. A first complementary coupling half 66 is provided in the side wall of a booth on the barge, which coupling half 66 comprises a vertical groove 67 that is designed to receive the top 63. The booth and the barge are not shown in Figure 11.

A second coupling half 68 is arranged in the groove 67, which second coupling half 68 is designed to be displaced along the groove 67 by a third actuator 69. On the coupling half 59 is arranged a second coupling half 70 that is complementary to second coupling half 68, and which is constructed with detent latches (not shown) for double-acting, releasable coupling with second coupling half 68.

The propelling vessel is coupled with the barge by running it into the booth, whereupon first coupling half 59 is pushed out from the side of the propelling vessel such that the top 63 goes into the groove 67. For this, an outwardly directed, relatively small force is applied along first axis 60 by first actuator 61, in order to avoid impact. The outwardly directed force acting on the coupling half 59 is then gradually increased in order to dampen the sideways movement of the propelling vessel and center the propelling vessel along the longitudinal axis of the booth. Centering is achieved by co-ordinating the coupling halves on either side of the propelling vessel.

Second actuator 65 is set to exert little or no force along second axis 64 while the top 63 is being guided into the groove 67. This allows the propelling vessel to move in the longitudinal direction, even after the top 63 has been positioned in the groove 67. The force from the second actuator 65 is then gradually increased in order to dampen the longitudinal movements of the propelling vessel. As previously mentioned, when the propelling vessel rolls about an axis that is not parallel to the longitudinal axis of the barge, great contact forces arise between the top 63 and the groove 67 in the longitudinal direction of the barge.

Advantageously, the force of the second actuator 65 is set such that it is overcome in the case if such great stress, whereby second actuator 65 will allow the propelling vessel to move slightly in the longitudinal direction, thereby reducing said contact forces. When the top 63 is positioned in the groove 67, second coupling half 68 is coupled to second complementary coupling half 70, and the vertical motion of the propelling vessel is dampened by a gradually increasing force from the third actuator 69, as explained previously. The top 63 with second actuator 65 is shown in section in Figure 12, where the actuator 65 is a hydraulic cylinder with a through piston rod 71 in a housing 72. The piston rod 71 is provided with a piston 73 that divides the housing 72 into a first cylinder chamber 74 and a second cylinder chamber 75. Packings 76 in the housing 72 provide a sliding seal against the piston rod 71. The top 63 is attached to the ends of the piston rod 71. A first hydraulic line 77 and a second hydraulic line 78 connect first and second cylinder chamber 74, 75 respectively with a hydraulic power source (not shown) .

Thus, in the case of the embodiment shown in Figure 11, the principle of the invention is applied several times, once for each of the actuators 61, 65, 69.

In Figure 13, reference number 79 denotes a propelling vessel that is to be coupled to a barge 80. The barge 80 is provided with a starboard coupling half 81 supported by a starboard manipulator 82, and a port coupling half 83 supported by a port manipulator 84.

Each of the coupling halves 81, 83 are provided with hemispherical recesses 85 and 86 respectively, which are designed to receive spherical complementary coupling halves 87, 88 on the starboard and port sides of the propelling vessel respectively. Each coupling half 81, 83 is equipped with detent latches (not shown) designed to retain the spherical coupling halves 87, 88 in their positions in the hemispherical recesses 85 and 86 respectively, and which are further designed to undo the coupling between a coupling half 81, 83 and the associated complementary coupling half 87, 88. Each manipulator 82, 84 comprises an arm, 89 and 90 respectively, where the length of the arm may be varied by use of a telescoping part 91, 92. The coupling half 81 is attached to the free end of the telescoping part 91, and the coupling half 83 is attached to the free end of the telescoping part 92.

Each arm 89, 90 is rotatably connected to the barge 80 via two hinges where the axes of rotation are mutually orthogonal. The starboard arm 89 is thus rotatable about a first axis 93 of rotation that lies in a plane perpendicular to the deck area of the barge 80 and parallel to the longitudinal axis 94 of the barge 80, and about a second axis 95 of rotation that lies in a plane parallel to the deck area of the barge 80, with the axis 95 of rotation at the same time being perpendicular to the longitudinal axis 94 of the barge 80. Correspondingly, the port arm 90 is rotatable about a first axis 96 of rotation that lies in a plane perpendicular to the deck area of the barge 80 and parallel to the longitudinal axis 94 of the barge 80, and about a second axis 97 of rotation that lies in a plane parallel to the deck area of the barge, with the axis 97 of rotation at the same time being perpendicular to the longitudinal axis 94 of the barge 80.

The arms 89, 90 are designed to be rotated about the respective axes 93, 95, 96, 97 of rotation by use of actuators (not shown). The telescoping part 91, 92 of the arms 89, 90 is designed to be displaced by actuators (not shown) .

The propelling vessel 79 is coupled to the barge 80 by setting the arms 89, 90 of the manipulators 82, 84 in a way such that the coupling halves 81, 83 are positioned at a suitable distance from the barge 80, at a suitable height above the surface of the water, and slightly out to either side of the intended post-coupling position of the propelling vessel 79. The propelling vessel 79 is run in between the arms 89, 90, which are then rotated in towards the propelling vessel 79, in such a way that each coupling halves 81, 83 comes into contact with and is coupled to the complementary coupling halves 87, 88 on the propelling vessel 79. During the coupling process, the position of the coupling halves 81, 83 is continuously readjusted by means of the telescoping part 91, 92 of the arms 89, 90, and through rotation about the axes 93, 95 and 96, 97 respectively, so that the distance to the complementary coupling halves 87, 88 gradually decreases. The coupling halves 81, 83 are manipulated so as to make them follow the movements of the complementary coupling halves 87, 88. Advantageously, this can be done by means of a servo system (not shown) connected to position measuring devices (not shown) that running perform measurements of the position of the propelling vessel 79 with respect to the barge 80.

In order to avoid impacts between the coupling halves 81, 83 and the complementary coupling halves 87, 88, the coupling halves 81, 83 are guided towards the complementary coupling halves 87, 88 with little force, and said actuators are set so as to give easily upon contact between the coupling halves 81, 83 and the complementary coupling halves 87, 88. Immediately after the moment of coupling, i.e. just as the hemispherical recesses 85, 86 in the coupling halves 81, 83 have received the spherical complementary coupling halves 87, 88, said detent latches are activated so that the coupling halves 81, 83 are coupled to the complementary coupling halves 87, 88. Then the actuators of the arms 89, 90 are made to exert a force that acts against the movements induced by the motion of the propelling vessel 79. The force of the actuators is gradually increased until the movements of the propelling vessel 79 are reduced to an acceptable magnitude, or until the propelling vessel 79 is still, relative to the barge 80. Variations in the barge 80 cargo are offset by moving the arms 89, 90.

In Figure 14, there is shown a propelling vessel 98 with a transverse and forward opening groove 99 in the bow portion. The groove 99 is designed to receive a transverse boom 100 provided on a barge 101, which boom 100 is supported by a starboard arm 102 and a port arm 103 rotatably attached at the end of the barge 101. The opening of the groove 99, measured in the vertical direction of the propelling vessel, should in front have a wide, converging opening, to make it easy to find the boom 100 with the groove 99. The arms 102, 103 are attached to a common rotatable shaft 104 arranged across the barge. The shaft 104 is designed to be rotated about its longitudinal axis 105 by an actuator (not shown) .

When the propelling vessel 98 is led towards the boom 100 to be coupled to the barge 101, the boom 100 is continuously adjusted to approximately the same height as the groove 99. Advantageously, a servo system (not shown) is used to accomplish this. When the boom 100 enters the groove 99 and contact is made between the propelling vessel 98 and the boom 100, the boom 100 is forced to follow the vertical movements of the propelling vessel 98. Said actuator is then brought to exert a gradually increasing force that acts against the vertical movements of the propelling vessel 98, as explained previously, and the vertical motion of the groove 99 is thus gradually dampened to an acceptable magnitude; if so desired all the way to zero. The propelling vessel 98 may be kept in contact with the boom 100 through use of the propulsion engine of the propelling vessel 98; however it is also possible to provide suitable detent latches in the groove 99 in order to keep the propelling vessel 98 coupled to the barge 101.

In Figure 15, there is shown a propelling vessel 106 with a transverse and upward opening groove 107 in the fore deck 108. The groove 107 is designed to receive a transverse boom 109 provided on a barge 110, which boom 109 is supported by a starboard arm 111 and a port arm 112 rotatably attached at the end of the barge 110. The arms 111, 112 are attached to a common rotatable shaft 113 arranged across the barge. The shaft 113 is designed to be rotated about its longitudinal axis by an actuator (not shown).

A ring-shaped groove 115 has been made in the transverse groove 107, which ring-shaped groove 115 is designed to receive a ring-shaped coupling half 116 on the boom 109. The coupling half 116 is designed to be able to expand in the longitudinal direction of the boom 109, thereby ensuring engagement with the sides of the ring-shaped groove 115.

When the propelling vessel 106 is led towards the boom 109 to be coupled to the barge 110, the fore deck 108 of the propelling vessel 106 is run in underneath the boom 109, which is then lowered until the ring-shaped coupling half 116 makes contact with the fore deck 108. As for previously described embodiments, a known servo system (not shown) may be used in order to avoid impact when the boom 109 is lowered towards the fore deck 108. The propelling vessel 106 is then displaced in the longitudinal direction through use of a propulsion engine, in a way such that the ring-shaped coupling half 116 finds the ring-shaped groove 115, whereupon the ring-shaped coupling half 116 is expanded, thereby interlocking with the propelling vessel 106. Dampening of the vertical motion of the propelling vessel 106 is implemented in the same way as explained previously, by use of said actuator (not shown) acting on the arms 111, 112.

Figure 16 shows a propelling vessel 117 about to run into a booth 118 at the end of a barge 119, where the booth 118 is provided with transverse straps 120 that are attached to the barge 119 at either end. Each strap 120 is provided with at least one roll 121 driven by an actuator (not shown) and designed to be able to adjust the free length of the strap 120.

When the propelling vessel 117 is to be coupled to the barge 119, the free length of the straps 120 is increase so as to make the straps hang at a depth sufficient to let the propelling vessel 117 pass over. The propelling vessel 117 is run into the booth 118, and the straps 120 are tightened using a limited force for contact with the underside of the propelling vessel 117. As explained previously, the limited tightening force causes the straps 120 to become flexible, the free length of the straps 120 adapting to the vertical movements of the propelling vessel 117.

By letting the rolls 121 gradually increase the tightening force of the straps 120, the vertical motion of the propelling vessel 117 is dampened. If so desired, the straps 120 are tightened in a way such that the essentially vertical movements of the propelling vessel 117 cease. Upon changes in the barge cargo, the free length of the straps 120 is adjusted with respect to the draught of the barge 119. The underside of the propelling vessel 117 may be provided with grooves, recesses or something else (not shown) designed to receive one or several straps 120 and ensure that the propelling vessel 117 does not slide astern and off the straps 120.

The invention gives advantages beyond an improved coupling of propelling vessel and barge. By the invention making it possible to carry out coupling in far more choppy seas than that provided by prior art, the costs connected with transport of oil in arctic waters may be reduced considerably.

In order to operate in arctic waters, the propelling vessel must be equipped and dimensioned for ice breaking, and the propelling vessel becomes relatively costly. However, the best part of the transport between an arctic area and the market still takes place in less demanding waters. Costly propelling vessels that are built for arctic waters will, when used in accordance with prior art, be outside of arctic waters for much of the time. The total costs may be reduced by having a small number of propelling vessels that are built for arctic conditions, and letting these handle transport in arctic waters, while ordinary propelling vessels steer the barges outside of the arctic area. This is made possible through the invention allowing exchange of propelling vessels near the arctic area, where, as may be known, the waters may be choppy.

It is also of interest to apply the invention to coupling of types of vessels other than propelling vessels and barges. The invention may be used to couple a shuttle tanker, which runs between a harbour, loading buoy or another structure, and a large oil ship, to said structure and/or oil ship respectively.

In connection with transport to far-off markets, the transfer of oil in open seas will result in better transport economics than reloading at a terminal in a known manner. Moreover, safety is increased as a result of large ships not entering narrow or weather exposed waters. The shuttle tanker may be coupled side by side with the oil ship, or the bow of the shuttle tanker may be coupled to the oil ship.

Claims

C l a i m s

1. A method of coupling a vessel with a structure or another vessel, typically for coupling a powered propelling vessel with a barge in a way such that the powered vessel can function as a propelling vessel for the barge, or possibly for coupling the powered vessel with a structure such as a loading buoy, or possibly also a fixed structure; in which the vessels are brought into a mutual initial position for coupling, whereupon at least one coupling half on one of the vessels is brought together with and releasably coupled to a complementary coupling half on the other vessel, thereby forming a releasable coupling between the vessels, w h e r e i

- a movable coupling half (e.g. 47) on one vessel (44), immediately after the moment of coupling, where contact is made with a corresponding, complementary coupling half (49) on the other vessel (42), is made to follow the movements of the o complementary coupling half (49) that are due to the relative movements between the vessels (42, 44), by the movable coupling half (47) being subjected to a limited force that is directed towards the complementary coupling half (49), so as 5 to make the movable coupling half (47) yield to a greater contact force between the coupling halves (47, 49),

whereupon the movable coupling half (47) is still subjected to a limited force effect, which limited force effect is varied in opposite phase to the intermovement of the vessels (42, 44),

which force effect is increased until the intermovement of the vessels has been reduced to an acceptable magnitude, or possibly to zero.

2. A device for implementing the method according to Claim 1, comprising at least one movable coupling half (2, 17, 19, 38, 40, 47, 53, 57, 59, 68, 81, 83, 100, 116, 120) on one of the vessels and a complementary coupling half (18, 21, 36, 37, 49, 54, 58, 66, 70, 87, 88, 99, 115) on the other vessel, in which the movable coupling half is associated with at least one actuator (1, 32, 39, 41, 48, 61, 65, 121) designed to bring the movable coupling half (2, 17, 19, 38, 40, 47, 53, 57, 59, 68, 81, 83, 100, 116, 120) into contact with, or possibly into engagement with, the complementary coupling half (18, 21, 36, 37, 49, 54, 58, 66, 70, 87, 88, 99, 115), w h e r e i n the actuator (1, 32, 39, 41, 48, 61, 65, 121) is adjustable with regard to the force it exerts on o the movable coupling half, the actuator more accurately being designed to apply a limited force to the movable coupling half, so as to make this yield to the movements of the complementary coupling half, and where the actuator is further designed to apply a gradually 5 increasing force in the opposite phase to said movements of the complementary coupling half.

3. Device according to Claim 2, w h e r e i n a movable coupling half (81, 83) is provided with a hemispherical recess (85, 86) designed to be coupled to a 30 complementary spherical coupling half (87, 88).

. Device according to Claim 2, w h e r e i n a movable coupling half comprises a boom (100, 109) designed to be guided into and coupled into a transverse groove (107) in the bow or the fore deck (99, 108) of a propelling vessel (98, 106).

5. Device according to Claim 2, w h e r e i n a movable coupling half comprises at least one strap (120) stretched across a booth (118) for a propelling vessel (117) at the end of a barge (119), and where said strap (120) is designed to be tightened to contact with the underside of the propelling vessel (117).

6. Device according to Claim 2, w h e r e i n at least one coupling half (47, 59) that is essentially vertically movable in a groove (45, 67) and is associated with an actuator (48, 61), is designed to be lowered to contact and coupling with a complementary coupling half on a propelling vessel (42).

7. Device according to Claim 6, w h e r e i n a first, essentially vertically movable coupling half (59) is provided for a second, essentially horizontally movable coupling half (68), where the coupling half (68) is associated with an actuator (69) and designed to cooperate with at least one wall in a groove (67) that constitutes a complementary coupling half (70) for said second coupling half (68).

8. Device according to Claim 2, w h e r e i n an essentially horizontally movable coupling half (53) on a propelling vessel is designed to co-operate with a complementary coupling half (54) in the form of a vertical groove (55) on a barge, where the coupling half (53) is equipped with at least one rotatable cogwheel

(57) designed to mesh with and roll along a toothed rack

(58) in the groove (55); where the cogwheel (57) has an actuator associated with it, which actuator is designed to apply limited and adjustable torque to the cogwheel

(57).