Abstract:
A device for transferring a product between a ship and a fixed installation. The device is supported at one end by a support structure and the other end is capable of being connected to the ship&#39;s manifold. The support structure includes a boom carrying a transfer pipe, rotatable about a vertical axis above the ship, and a deformable transfer device, one end of which is connected to the pipe, and the other end is mobile between a stowed position proximate the boom and a position for connection to the ship&#39;s manifold. The invention is useful for transferring liquefied natural gas.

Description:
FIELD OF THE INVENTION 
   The invention relates to a system for transfer of a fluid product, particularly a liquefied natural gas, between a transport vehicle, such as a ship, and an installation for receiving this product or supplying the ship with this product, which has a device for transferring the product between the ship and the installation, that is supported at a first end by a support structure and has a second end that can be connected to a manifold device of the vehicle. 
   BACKGROUND 
   Known transfer systems for the transfer of liquefied natural gas are not suitable for use under severe environmental conditions. 
   The present invention offers a system that eliminates the above-mentioned disadvantage of known systems. 
   SUMMARY OF THE INVENTION 
   To attain this aim, the transfer system according to the invention has a the support structure with a carrier boom for a rigid transfer pipe that is mounted on a mooring post, rotating around a vertical axis above a transport vehicle, and a deformable transfer device, a first end of which is connected to the transfer pipe, and a second end that can be moved between a storage position near the boom and a position of connection to a manifold device of a ship. 
   According to one feature of the invention, the deformable transfer device is connected to the fixed transfer pipe at the free end of the boom, and the connection of the deformable transfer device to the fixed transfer pipe suspends the deformable transfer device from the boom. 
   According to another feature of the invention, the mooring post is a single mooring point, and the vehicle can turn freely about the mooring post in order to orient itself in the direction of the elements (swell, wind, current). 
   According to another feature of the invention, the boom is carried along by the ship by the deformable transfer device when the transfer device is connected to the manifold of the ship. 
   According to yet another feature of the invention, when the deformable transfer device is not connected to the manifold, the boom is free to orient itself in the direction of the wind in order to resist storms under survival conditions. 
   According to yet another feature of the invention, braking means in the boom rotational system to avoid an excessive number of small movements. 
   According to yet another of the invention, the boom and deformable transfer device are configured such that the stresses exerted on the boom pass through its neutral axis so that the boom is subjected only to simple bending. 
   According to yet another feature of the invention, the deformable transfer device filters the ship movements so that small movements of the ship around its average position do not generate sufficient lateral stress to lead to rotation of the boom, and the device absorbs high frequency movements and avoids stress peaks. 
   According to yet another feature of the invention, the deformable transfer device is stored under the boom while oriented parallel to the axis of the boom, and is connected to the fixed pipe by a rotating joint that makes possible a rotation into a position perpendicular to the longitudinal axis of ship during establishment of a connection to the manifold of the ship. 
   According to yet another feature of the invention, the deformable transfer device has, at its free end, a device for connection to the manifold of the ship. 
   According to yet another feature of the invention, the connection device and the manifold of the ship have means for centering during dynamic connection of the transfer device to the manifold. 
   According to yet another feature of the invention, the deformable transfer device has a number of pairs of transfer arms, free ends of the inner arms are connected to a shared part connected to the fixed pipe by the rotating joint, and outer arms carrying connectors. 
   According to yet another feature of the invention, the deformable transfer device has at least one pair of tubular arms which are articulated to one another, namely an inner arm connected to the fixed pipe and an outer arm that carries a connector at a free end. 
   According to yet another feature of the invention, the deformable transfer device has at least one cryogenic hose that is connected to an end of the fixed transfer pipe and another end carries a connecting device. 
   According to yet another feature of the invention, the cryogenic hose in a storage position is suspended under the boom at the end that carries the connector and extends as a chain. 
   According to yet another feature of the invention, a stand-off arm are associated with the cryogenic hose maintains a predetermined separation between the ship and the boom during the transfer of fluid and/or a predetermined radius of curvature of the hose during connection/disconnection. 
   According to yet another feature of the invention, stand-off arm is connected to the manifold of the ship during transfer of fluid. 
   According to yet another feature of the invention, the deformable transfer device has a number of cryogenic hoses joined at first ends that are connected to the fixed pipe, and each of which carries a connector at a free end. 
   According to yet another feature of the invention, the stand-off arm is suspended under the boom by a connecting component, such as a cable or a connecting rod, to form a balance beam that ensures that a predetermined distance between the ship and the boom is maintained during transfer of fluid and that reduces or cancels the stresses exerted on the connectors or manifolds during establishment of a connection and during transfer. 

   
     BRIEF DESCRIPTION OF DRAWING FIGURES 
     The invention will be better understood, and other aims, characteristics, details and advantages of it will appear more clearly in the following explanatory description given with reference to the appended diagrammatic drawings, given only as examples, illustrating several embodiments of the invention, and in which: 
       FIG. 1  is an oblique view of a system for transfer of a fluid according to the invention; 
       FIG. 2  is a diagrammatic top view of the system according to  FIG. 1 ; 
       FIG. 3A  is a view, partially cut-away, on a larger scale, in the direction of arrow III A of  FIG. 2 , and illustrates a first embodiment of a deformable transfer device, in its storage position under the support boom; 
       FIG. 3B  shows the transfer device according to  FIG. 3A  in its position of connection to the manifold of the ship; 
       FIG. 3C  is a partial view in the direction of arrow III C of  FIG. 3B ; 
     Each of  FIGS. 3D to 3I  illustrates a step in the process of connection of the transfer device according to  FIG. 3A  to the manifold of the ship. 
       FIG. 4A  is a view in the direction of arrow III A of  FIG. 2  of a second embodiment of the deformable transfer device according to the invention, in its storage position under the boom; 
       FIG. 4B  shows the transfer pipe device according to  FIG. 4A  in its position of connection to the ship; 
       FIG. 4C  is a view in the direction of arrow IV C of  FIG. 4B ; 
       FIG. 4D  is a view in the direction of arrow IV D of  FIG. 4B ; 
       FIG. 4E  is a partial view in the direction of arrow IV E of  FIG. 4D ; 
     Each of  FIGS. 4F to 4L  illustrates a phase in the process of connection of the transfer device according to  FIG. 4A  to the ship; 
     Each of  FIGS. 4M to 4P  illustrates a step in the process of disconnection of the transfer device according to  FIG. 4A  from the ship; 
       FIGS. 5A and 5B  are views similar to the views  4 B and  4 C of another embodiment of the transfer device according to  FIG. 4A ; 
       FIG. 6A  is a diagrammatic view of a third embodiment of the deformable transfer device according to the invention, in its position of connection to the ship; 
       FIGS. 6B and 6C , respectively, are views in the directions of arrows VI B and VI C of  FIG. 6A ; 
       FIG. 7  is a view similar to that of  FIG. 6A  of a variant of embodiment of the transfer pipe device according to this figure; 
       FIG. 8A  is a view in the direction of arrow III A of  FIG. 2  of another embodiment of the transfer pipe device according to the invention; 
       FIG. 8B  illustrates the transfer pipe device according to  FIG. 8A  in an intermediate position during its connection to the ship. 
       FIG. 8C  shows the transfer pipe device according to  FIG. 8A  in its position of connection to the manifold of the ship; 
       FIGS. 9A to 9C  are diagrammatic views for illustrating the process in which the boom is carried along by the ship. 
   

   DETAILED DESCRIPTION 
     FIG. 1  illustrates by way of example a system  1  for transfer of a fluid, in the example, liquefied natural gas (LNG), between transport ship  2  and an installation, for example, a fixed installation for which only submerged cryogenic transfer lines  3  are represented. The transfer system essentially entails mooring post  5 , for example, at a coastal site open to the sea, if applicable, at an off-shore site, in the form of a column that rests at  6  on the ocean bottom, and a long horizontal boom  8  mounted on upper emerging part  9  of post  5  and rotatable around its vertical axis, well above ship  2 , as well as a deformable tubular device for the transfer of fluid  11 , which is connected at one end, indicated by  12 , to fixed pipe  10  that extends along boom  8  and through the mooring post and connected to submerged lines  3  by the intermediary of a rotating fluid joint with a vertical axis. The other end  13  of the deformable transfer device can be moved between a storage position at  14  under boom  8  and a position of connection to manifold device  15  of ship  2  located near the longitudinal center of this ship, as in the case of standard liquid natural gas tankers. 
   Ship  2  is moored by mooring cable  17  to single mooring point  18  of ring  19  which rotates freely around the axis of the mooring post in the form of column  5 , cable  17  being attached at front part  20  of the ship. 
     FIG. 1  moreover shows that boom  8  is, in addition, suspended by support cables  22  from part  23  at the summit of rotating mooring column  9 . The static equilibrium of the boom can be obtained by means of counterweight  7  at the end of the “counter” part of the boom that is supported, like the boom, by cables  22 , that is to say, the arm of the boom opposite that carrying the transfer device. This structure generally has the advantageous effect of not imparting any fixed end moment to the device for guiding boom  8  in rotation about a vertical axis, which would otherwise appear because of its large overhang. 
   Boom  8  is motorized so that it can be maneuvered, but it is capable of rotating freely, which allows it to orient itself in the direction of the wind in the storage position. In transfer configuration, it follows ship  2  in its changes of average position that depend in particular on the direction of the wind, of the current, and of the waves. During a transfer of liquefied natural gas between ship  2  and the fixed installation, boom  8  is carried along by the ship via the intermediary of deformable transfer device  11 . By making the resultant of the stresses exerted on the boom pass through the neutral axis of the boom, the boom is subjected only to simple bending stress and not to torsional stress. As will be described hereafter, deformable transfer device  11  is realized in such a way as to produce a filtering of the movements of the ship. The small movements of the latter around its average position do not generate sufficient lateral stress to lead to rotation of the boom. Only the changes of average position of the ship lead to rotation. The device “absorbs” the small movements of the ship. Furthermore, the device is capable of absorbing the stress peaks. 
   With reference to  FIG. 9 , the principle of entrainment of the boom, constituting an important characteristic of the invention, will be described. This figure diagrammatically shows a counterweight, such as counterweight  108  for example, at the end of stand-off arm  103  according to  FIG. 7 , suspended from the end of a cable such as cable  68  of this figure, under the end of boom  8 . The suspension is done at the site of the neutral axis. When there is a relative lateral movement between the stand-off arm, and thus the counterweight, with respect to the boom, the counterweight, because of its weight P, induces at the site of suspension from the boom by cable  68  a force T that resolves into vertical component P and horizontal component F. In the hypothetical case of negligible friction during rotation of the boom, force component F will move the boom to the point at which this component becomes zero, as seen in  FIG. 9C . 
   A first embodiment of fluid transfer device  11  according to the invention will now be described with reference to  FIGS. 3A to 3I . According to this embodiment, the device has three pairs of articulated arms, which are connected in parallel to fixed pipe  10  supported by boom  8 , each pair having inner arm  25  and outer arm  26 . The two arms are connected to one another by articulation  28  of the type with two rotating joints with perpendicular axes, thus forming a universal joint. The upper end of each inner arm  25  is connected by rotating joint  29  to a limb of E-shaped part  30 , whose base is connected by rotating joint  31  to fixed pipe  10 . The axes of rotation of the two joints  29  and  31  are perpendicular. The free end of each outer arm  26  carries connector  33  allowing connection of the arm to manifold  15  of the ship. The connector is joined to the arm by means of two rotating joints  35  with perpendicular axes. Rigidly associated with the connector is centering rod  36 , popularly called a “spindle,” which is configured to be received in complementary centering funnel  37  which, in the embodiment which is represented, is part of connecting module  38  intended to be interposed, or integral with, the ship, between manifold  15  of the ship and connector  33  of outer transfer arm  26 . Connecting module  38  carries, for each arm, winch  39  around which a cable  40  will be wound that passes through funnel  37  and is attached at the end of centering spindle  36 . The module is also provided with a device for support on the manifold platform of the ship. 
   Connecting module  38  which, as seen in the figures, constitutes an extension of the manifolds of the ship, is stored on either the ship or the transfer system. In the latter case, in order for it to be positioned on the manifolds during fluid transfer, the module will be transported to the ship by a service vehicle, for example, or be lowered by a winch from the end of the boom onto the ship. 
   It should also be noted that, according to the explanations given on the subject of the entrainment of the boom during a fluid transfer, the masses are, as much as possible, brought to the bottom of the inner arm. In order to find an optimum, it will be possible to provide a counterweight at this location as indicated at  41  in  FIG. 3B . In order to avoid excessively increasing the counterweight in order to counteract the possible effects of an unfavorable wind, it will be possible to provide the counter-boom with flaps or panels (not represented) that can be adjusted or concealed during transfer for the purpose of balancing the wind loads on the boom and counter-boom (a system neutral with respect to the general axis of vertical rotation). 
   The structure making it possible to maneuver deformable transfer device  11  comprise maneuvering cable  42 , which can be wound around winch  43 , mounted under boom  8 , and whose free end is attached to transfer device  11  at the site of joint  28  between the two arms. This control makes it possible to lower the two arms in a position folded on one another. Another maneuvering cable  45  is provided for unfolding the two arms, one end of cable  45  being windable on or unwindable from winch  46  mounted high on inner arm  25 , and the other end of cable  45  being attached at  47  to arm  26  near the free end of the arm  26 . The winches can be controlled, in particular remote-controlled, in any appropriate known manner. The rotation of transfer device  11  formed by the three pairs of arms can be controlled, for example, by means of a hydraulic actuator or hydraulic motor, which is not represented. This rotation can also be effected by winching from a service ship. The process for connection of transfer device  11  to manifolds  15  of ship  2  will be described hereafter with reference to  FIGS. 3D to 3G . In the resting state or in survival conditions, the device is stored in the folded state under boom  8 , maneuvering cables  42  and  45  being wound, respectively, on winches  43  and  46 . To make a fluid transfer, transfer device  11  is first lowered by unwinding cable  42  from winch  43 . The device then pivots around joints  29 , according to  FIG. 3D , until it is in its essentially vertical position. Device  11  is then rotated around joint  31  by an angle of 90 20  into the position represented in  FIG. 3E , wherein the axes of rotation ofjoints  29  are oriented essentially parallel to the neutral axis. Unwinding cable  45  from winch  46  allows arms  25  and  26  to unfold, as seen in  FIG. 3F , to the position illustrated in  FIG. 3G . Then, after connecting module  38  has been previously mounted or integrated to manifold device  15  of the ship, if applicable, cable  40  attached to the end of the tip of spindle  36  is connected to winch  39  of the connecting module. Given that the cable passes through funnel  37  of the module, winding the cable on the winch, necessarily brings connector  33  to its module connection position, brought about by funnel  37  receiving centering rod  36 , even in a “dynamic” mode. 
     FIGS. 3H and 3I  illustrate the process for disconnection of transfer device  11  from connecting module  38 , this module remaining on the ship or being brought in any appropriate manner to the transfer system. Unwinding cable  40  from winch  39  enables the separation of connector  33  from the module to the point that cable  40  is unwound and falls in the water. During this disconnection phase (survival or emergency phase), a set torque value for separation of boom  8  from the ship will be given to the system for hydraulic maneuvering of boom  8 . Then the folding of arm  26  on arm  25  of deformable transfer device  11  is effected by actuating winch  46 , and rotation of the latter around its joint  31 U, and raising of the folded device to its storage position according to  FIG. 3A  is effected by winding cable  42  on winch  43 . 
   A second embodiment of the fluid transfer system according to the invention will be described hereafter with reference to  FIGS. 4A to 4P . This embodiment has the particularity, with respect to the embodiment just described, that the deformable transfer device has cryogenic hoses bearing the reference  50 . As seen in  FIGS. 4A to 4E , the device represented as an example has three hoses  50 , mounted in parallel, that are connected to an end of an E-shaped part  30  and are connected to fixed pipe  10  by the intermediary of two rotating joints  31  with perpendicular axes. The cryogenic hoses could be hoses such as those as developed, for example, by the company Coflexip Stena Offshore. The other end of each cryogenic hose carries connector  33 , which is provided with a centering rod called a “spindle”  36 , and which is intended for mounting on manifold device  15  of the ship, if applicable, via the intermediary of connecting module  38 . 
   Each connector  33  is suspended by a cable  56  which can be wound on winch  57  that is mounted on support cross piece  59 , which is itself attached on an arm in the form of a bar  60  that is intended for maintenance of a minimum separation between the ship and boom  8 . In effect, when the transfer hoses are arranged in the manner of chains between the end of boom  8  and manifolds  15  as in the present case, the horizontal components of the tensions tend to bring the boom toward the ship. Furthermore, bar  60  participates in putting boom  8  in rotation according to the principle already described. This bar carries, at an end opposite from the end carrying cross piece  59 , another cross piece  61  whose exterior longitudinal surface carries projecting elements  63  delimiting between one another three V-shaped seats  64 , each intended to receive a hose  50 . At each end, cross piece  61  has projecting lateral lugs  65  for keeping the hoses near their seat  64 . Stand-off bar  60  is suspended at its front end by cable  67  and at its rear end by two cables  68  from transverse beam  70  that also carries E-shaped part  30  to which the three hoses are connected, each cable  68  extending between an end of beam  70  and an end of crosspiece  61 . Each hose is moreover provided, in the part situated between cross piece  61  and part  70 , with spacers  72 . It is also observed that the front end of stand-off bar  60  carries spindle  74  that is mounted to pivot on two ball joints (three directions of rotation) and is intended to cooperate with complementary funnel  75  mounted on connecting module  38 , through a cable  76 , which can be wound on a winch  77 . The winch  77  is also provided on the connecting module. Of course, this module carries winches for winding the cables for engagement and for maintaining the spindles of connectors  33  in their associated funnel, as in the case of the first embodiment. 
   Transfer device  11  formed by the set of hoses  50  can be maneuvered by two maneuvering cables attached to the front and rear ends of stand-off arm  60 , namely front cable  80  that can be wound on winch  81  mounted under boom  8 , and two cables  83  that can be wound on two winches  84  also arranged under the boom. The two winches  81  and  84  are separated from one another in the longitudinal direction of the boom. It is also important to note that arm  60  can be provided, at its rear end, with counterweight  86  according to the principle already described. It is also possible to provide each hose  50  with curvature stiffeners  87  and  88  at, respectively, its upper end and at its intermediate curved part intended to butt against cross piece  61  when the hoses are connected to the manifolds of the ship, as seen in  FIG. 4B . It should be noted that depending on the nature and the characteristics of the hoses, they can be used instead of cables  68  as a structural link between beam  70  and cross piece  61 , a device for fastening the cross piece to the hoses being provided in that case (but not shown). 
     FIGS. 4F to 4L  illustrate the process of connecting hoses  50  to manifold  15  of ship  2 . In their rest position, as seen in  FIG. 4A , stand-off bar  61  is held under boom  8  by cables  80  and  83  which are completely wound on their winches  81  and  84 . The bar extends parallel to the boom. The hoses are suspended in the manner of chains. 
   In order to connect the hoses to the manifold of a ship, maneuvering cables  80  and  83  are unwound, as seen in  FIGS. 4F and 4G . It can be seen that the curvature of the exterior part of the hoses is limited due to the fact that the hoses butt against cross piece  61  while being engaged in seats  64  provided for this purpose. The engagement ensures a well defined position of the hoses during the remainder of the connecting process and during the period of transfer and of later disconnection. Device  11 , that is to say, the set of three hoses is then rotated by an angle of 90°, through rotating joint  31  or two superposed joints, to the position represented in  FIG. 4H  in which the hoses extend perpendicular to the longitudinal axis of the ship. As seen in  FIG. 4I , device  11  of hoses,  50  is pulled, using cable  76  interconnected between the tip of spindle  74  associated with bar  60  and winch  77 , towards the connecting module mounted beforehand on manifold  15  of the ship. The engagement of spindle  74  in funnel  75  ensures the correct positioning of transfer device  11 . Then suspension cables  56  of connectors  33  of the hoses are unwound from their respective winches  57  and, as described in describing the first embodiment of the transfer device, the connection between the hoses and the connecting modules is ensured. It is observed that bar  61 , by being connected to an end of the ship and by holding the hoses at its other end, ensures a suitable separation between the boom and the ship. 
   According to  FIGS. 4M and 4P , disconnection of the hoses takes place in a manner that is the reverse of the connection process just described: first of all by disconnecting the hoses from the connecting modules, then by winding suspension cables  56  of the connectors of the hoses on their winch  57  ( FIG. 4M ), then by disconnecting stand-off bar  60 , effecting a rotation, and finally raising this bar by winding maneuvering cables  80  and  83  on their respective winches  81  and  84 . 
     FIGS. 5A and 5B  illustrate a variant of the embodiment represented in  FIGS. 4A to 4P . This variant relates to the stand-off arm, which has the general shape of a rectangle, bearing the general reference  90 , formed by two longitudinal bars  91  interconnected at the center and at their front and rear ends by respective cross pieces  92 ,  93  and  94 . The cross pieces  93  and  94  respectively fulfill the functions of cross pieces  59  and  61  of the embodiment according to  FIGS. 4A to 4P . Hoses  50  now butt directly against rear cross piece  94 , and bars  90  and  91  extend beyond cross piece  94  by part  95 , bent towards the outside, which can be provided at its free end with counterweight  96 . 
     FIGS. 6A to 6C  illustrate another variant of the arrangement for supporting and holding the hoses which has the particularity that stand-off arm  98  is associated with each hose  50 , each arm being formed essentially by two longitudinal bars  99  relatively close together and interconnected at the ends and in the middle by cross pieces  100 . Each hose is engaged between the two bars  99  of its arm  98 . Arm  98  is connected to the end of a hose by a hose end/stand-off arm ball joint connection. The rear end of each bar carries counterweight  101 . As seen in  FIG. 6B , each arm  99  is suspended from the transverse carrier beam of the shared E-shaped part, to which the cables are connected, by front cable  67  and rear cable  68  extending, in the state of connection of the hoses to the ship, in front of the hoses. 
     FIG. 7  illustrates another variant of execution of the transfer hose device, according to which the separation between ship  2  and boom  8  is maintained by bar  103  without intermediate support for hoses  50 , and which is suspended under the boom as by cables  67  and  68 . The rear end of arm  103  carries counterweight  108 . In this embodiment, hoses  50  extend freely, in the manner of a chain, between rotating beam  106  and the front end of stand-off arm  103 . 
     FIGS. 8A to 8C  illustrate a version of execution of the transfer device  11 , which is distinguished from the device according to  FIG. 7  essentially by the fact that the points of connection of hoses  50  and of support cables  68  of the stand-off arm are situated at the two ends of arm  110 , which is rotatably mounted under boom  8  by rotating joint  31  or two superposed rotating joints. As shown in  FIG. 8A , this arm  110  is oriented parallel to the axis of the boom when the transfer device occupies its rest position under the boom, arm  103  then also extending parallel to the boom. 
   It is observed that the suspension by cable  68  of arms  103  near its middle zone and the counterweight ensure a stable state of equilibrium and moreover make it possible to reduce the maneuvering stresses during connection to the manifolds of the ship, and the stresses on the manifolds or the manifold extensions. Of course, this effect is also produced in a more or less pronounced way in the other embodiments. 
   It emerges from the description that the invention offers a transfer system that, while having a simple structure, is completely suitable for operation under severe environmental conditions. Thanks to the use of a boom, the transfer system can have a single mooring point while being applicable to ships whose manifolds extend perpendicular to the longitudinal axis of the ship and in its middle (standard liquid natural gas tankers). Of course, these manifolds need not be arranged in the central part of the ship, as in the case which is represented. It should be noted that the transfer system according to the invention can be realized in the form of an off-shore station. 
   Of course, numerous modifications can be made to the embodiments described and represented without departing from the scope of the invention. Thus, the support of the boom could be installed on a floating support, such as a floating unit for storage or production of liquefied natural gas. In the preceding description, the LNG transfer lines alone were described. It is also possible, of course, to provide a circuit for the return of gas in the form of vapor. In this case, it will be advantageous to use rotating multi-passage coaxial fluid joints in the axis of rotation of the boom in the mooring column. The same is true for joint  31  for connecting the deformable transfer device to the rigid pipe. Concerning joint  31 , 360° rotation not being necessary, either rotating single-passage joints on the same axis, or hoses could advantageously be used. Such joints are known, and need not be described here. 
   In the embodiments described and represented, the deformable transfer devices are connected to the manifold device from below. It would of course be possible to provide transfer devices that are connected to the manifold from above, that is to say, by lowering. In this case, it is sufficient to make the connectors of the transfer device open, if applicable, towards the bottom and the connectors of the manifold device open towards the top, vertically, the spindle and the funnel extending correspondingly, parallel to the axes of the connectors. 
   In order to give some indications as to the dimensions of the system according to the invention, only as an example, the boom could advantageously have a length between 200 and 220 meters, and its height above the level of the water could be on the order of 50 meters. 
   It should be noted that an essential characteristic of the invention lies in the fact that during the sensitive phases of connection/disconnection of the deformable transfer device, a single cable executes the functions of support/hoisting of the mobile end of this deformable system and of guiding, in particular, laterally. This single cable is arranged along the axis of the main movements of the ship (heaving).