EP2429893A2

EP2429893A2 - Method for transferring fluids between a first ship and a second ship, and transfer system for implementing said method

Info

Publication number: EP2429893A2
Application number: EP10728756A
Authority: EP
Inventors: Bernard Dupont
Original assignee: Europeenne dIngenierie Mecanique SA EURODIM
Current assignee: Technip Energies France SAS
Priority date: 2009-05-13
Filing date: 2010-05-12
Publication date: 2012-03-21
Also published as: CA2760626C; MX339344B; AU2010247229B2; US9260164B2; FR2945510B1; BRPI1007722B1; US20130025726A1; AU2010247229A1; RU2011145867A; RU2548306C2; KR20120024746A; CN102548839A; FR2945510A1; WO2010130960A2; CA2760626A1; BRPI1007722A2; MX2011012076A; WO2010130960A3

Abstract

The invention relates to a method for transferring fluids between a first ship, called a barge (1), and a second ship (2), called a shuttle, according to which the shuttle is positioned at a pre-determined distance from the barge (1), and a flexible fluid transfer conduit (7) is guided from the barge to the shuttle (2). The method is characterised in that the shuttle (2) is placed in a position wherein the shuttle is laterally offset from the barge (1) while being essentially parallel to the longitudinal axis of the barge, and a fluid transfer system (7, 9, 28) is provided, which enables the shuttle to be moved in the lateral and longitudinal directions in relation to the barge, during a transfer. The invention can be used for the transfer of liquefied natural gas.

Description

"Method of transferring fluids between a first vessel and a second vessel and transfer system for carrying out this method".

The invention relates to a method for transferring fluids between a first vessel called a barge, and a second vessel called shuttle, in which the shuttle is positioned at a predetermined distance from the barge and passes at least one flexible transfer conduit therefrom. of fluid to the shuttle. The invention also relates to a transfer system for implementing this method.

According to the methods of this type, which are known, the shuttle is positioned to be disposed substantially in the axis of the barge at a distance of the order of 70 to 80 meters before operating the connection of the flexible conduits to connection device provided on the shuttle. This one is moored to the barge by a hawser during the transfer or is in dynamic positioning. However, the tandem positioning has major disadvantages. Since the barge and the shuttle are positioned according to the wind, currents and swell, there is a great risk that the shuttle is in the area of the direction of the flame generated by the flare. is part of the standard equipment of the barge, on the one hand, and that the shuttle, by accidentally advancing, collides frontally with the rear part of the barge. These risks already make it difficult to transfer crude oil from the barge to the shuttle, but make it virtually impossible to transfer liquefied natural gas (LNG) from the barge to the shuttle.

The invention aims to propose a solution to the problems that have just been stated.

To achieve this goal, the method according to the invention is characterized in that the shuttle is placed in a position in which the shuttle is laterally offset from the barge while being oriented substantially. parallel to the longitudinal axis of the barge and that there is provided a fluid transfer system which allows a large displacement of the shuttle in the lateral and longitudinal directions, relative to the barge, during a transfer.

According to one characteristic of the invention, cryogenic hoses for the transfer of liquefied natural gas are used as the flexible transfer conduit.

The system according to the invention, for the implementation of this method is characterized in that the barge carries a device for storing at least one flexible conduit, optionally a cryogenic fluid, of a length between 60 and 120 meters, whose pipe output mechanism is rotatable about a vertical axis and that the receiving device of the pipe connection tip, provided on the shuttle is also rotatable about a vertical axis .

According to a characteristic of the system according to the invention, the storage device is in the form of a wheel with a diameter of between 20 and 50 meters, around which the pipe is wound and from which it can be unwound at the same time. a fluid transfer, this wheel being rotatable about a horizontal axis and pivotable about a vertical axis.

According to another characteristic of the invention, the flexible pipe is wound in a peripheral groove of the wheel in a turn.

According to yet another characteristic of the invention, the wheel comprises a plurality of juxtaposed storage grooves, where appropriate for storing a plurality of flexible ducts.

The invention will be better understood, and other objects, features, details and advantages thereof will appear more clearly in the explanatory description which follows, with reference to the appended schematic drawings given solely by way of example. illustrating an embodiment of the invention and in which: Figures 1 and 2 are two views from above showing a barge and a shuttle in two fluid transfer positions, according to the invention;

FIG. 3 is a view in the direction of the longitudinal axes of the two vessels, in the direction of the arrow III of FIG. 2;

FIG. 4 is a view on a larger scale of the cryogenic flexible storage wheel according to the invention, mounted on the barge, according to FIG. 3;

- Figure 5 is a top view of the storage wheel in the direction of arrow V of Figure 3;

- Figure 6 is a view similar to Figure 4 but shows the storage wheel in a rest position in which the hoses are wrapped around the periphery of the wheel;

FIG. 7 is a view on a larger scale of the device for receiving the hoses of the shuttle, according to FIG. 3;

FIG. 8 shows this device of FIG. 7 before receiving the hoses;

FIG. 9 is a view from above in the direction of arrow IX of FIG. 8. The invention will be described hereinafter, by way of non-exclusive example, in its application to a transfer of liquefied natural gas (LNG). from a first vessel, a barge 1 LNG production, a second vessel, a shuttle 2. As shown in Figures 1 to 3, to achieve such a transfer of LNG, the shuttle 2 is placed in dynamic positioning in a position in which it is laterally offset from the barge and oriented substantially parallel to the longitudinal axis thereof, the side opposite that of the flare 3 which is located at one end of the barge and is part of the standard equipment of the barge, such as housing parts 4 and a mooring drum 5, provided at the other end thereof. The typical difference between the barge and the shuttle is of the order of 70 to 80 meters. The transfer is done using cryogenic hoses 7 which are stored on the barge and are of great length so that an LNG transfer can be done in good conditions even in the case of a major displacement of the shuttle 2 relative to the barge 1. The shuttle 2 is held in position relative to the barge 1 by a dynamic positioning system provided on the shuttle 2. For this purpose it is equipped with side pusher with automatic control by the control system. positioning, for example bow thrusters. The dynamic positioning system automatically controls the shuttle in caval, yaw and yaw by acting on the various thrusters such as the main and lateral thrusters so as to maintain the shuttle in a position and / or in a predetermined course relative to a fixed reference or mobile, in this case the barge 1. The position of the reference and the position of the shuttle is known by combining information positioning systems (satellite, GPS, inertial units, radar and the like).

According to the invention, the dynamic positioning system is used to maintain the shuttle relative to the barge in a position laterally offset from the barge and oriented substantially parallel thereto without the shuttle being connected to the barge by means such as a hawser. Thus, according to the invention, a transfer of fluid between the shuttle and the barge, thanks to the possibilities of dynamic positioning of the shuttle no longer requires that the longitudinal axis of the shuttle is pointed towards the stern of the barge. To implement an LNG transfer from the barge 1 to the shuttle 2, the barge comprises, on the end portion on which the flare 3 is located, but close to the edge which is opposite the shuttle 2, for transfer storage device, two large wheels 9 with a large storage capacity, of a diameter for example between 20 and

50 meters, which each house, in two peripheral grooves 10 of the rim 11, two cryogenic hoses 7.

Each wheel is rotatably mounted about a horizontal axis 12 supported at the top of a tower-like structure 13 disposed on a plate-shaped member 14 which is rotatably mounted about a vertical axis on a base 15 located near the edge 16 of the ship. Thus the axis of rotation 12 of the wheel is able to pivot about a vertical axis.

In the example shown, each wheel has two peripheral grooves housing a hose 7, one end of which is fixed to the rim and connected to the pipe of the barge, while the other end is free and carries a connecting end 17 to the receiving device provided on the shuttle. As can be seen in particular in FIG. 6, the end piece 17 carries the connection flange 18. The two end pieces 17 of the two flexible tubes 7 are mounted on a common support which carries a centering pinch 19 oriented parallel to the axes of the connectors while being disposed above them, as well as a fall brake winch 20. To ensure the correct winding of each hose in the groove of the rim of the wheel, on the one hand, and for the correct alignment between the unrolled hose and the wheel, on the other hand, it comprises a device 22 for guiding each hose at the moment of its exit from its storage groove, which essentially comprises a guiding sleeve 23 through which the hose passes. and which is maintained by a structure of support bars 24 in a position in which the sleeve is axially aligned with the tangent of the hose storage groove corresponding to the exit point of the hose of this groove. To the wheel is also associated a winch 26 which is placed on the rotatable support plate 14 of the wheel and whose function is to rotate the wheel by means of a cable 27 whose one end is fixed to the wheel and whose other end is wrapped around the winch. This winch also takes into account the fact that, in the idle state of the wheel in which the hoses are fully wound around the rim in their respective grooves, the free end carrying the connecting end 17 hangs freely vertically. of the wheel. Of course, the device for driving in rotation of the wheel may be completed by motor drive means of the axis 12 of the wheel, which could operate parallel to the winch or in case of failure thereof. Referring in particular to FIGS. 3 and 7 to 9, it can be seen that the arrangement for receiving the cryogenic hoses 7 on the shuttle 2 is in the form of a head 28 for supporting two connection devices 29, each of which has two connectors. 30 connection of the two connection ends 17 of the two flexible 7 wound around a wheel. The head 28 is rotatably mounted about a vertical axis on a support tower 31 placed, according to the examples shown, either on the front part (Figure 1) or on the rear part (Figure 2) of the shuttle. Each device 29 for supporting each pair of connectors 30 for connecting the common support device of the two connection ends 17 of a pair of hoses comprises a receiving and centering member of the common pinch 19 of the two ends, in the form of a trumpet 32 and a winch 33 for winding the cable 34 which passes through the trumpet and is intended to be fixed during a transfer, at the tip of pinoche 19 to pull it to the shuttle until the pinch in the trumpet. To ensure the angularly correct orientation of the support of the two ends 17, the support 29 of the connectors comprises a fork 36 which ensures the correct angular positioning of the flanges 18 of the end pieces, by means of a roller 38 which is arranged on the support the ends 36 above, in cooperation with the roller 38, makes it possible to make up for the angular positioning defects of the support of the end pieces 17, which is relatively small, since the arrangement of the pinch over the flanges already ensures an approximately correct angular positioning thereof with respect to the connecting flanges, under the fact of the weight of these flanges, the center of gravity being approximately vertically under the pinch.

It follows from the description that has just been made, and figures, that the storage on the wheels can have a diameter of between 20 and 50 meters, a very long length of flexible, between 60 and 120 meters allows the shuttle to make significant displacements, with respect to the barge, longitudinally and transversely, during a transfer of LNG. On the other hand, the possibility of the storage wheels on the barge and the head 28 for receiving the hoses on the shuttle has the extremely advantageous result that the wheels and the head always orient themselves so that the hoses are not subjected at lateral or torsional stresses and always extend in a chain during a transfer between their two ends, one integral with the wheel and the other connected to the receiving head of the shuttle. Regarding the routing of the hose ends of the barge to the shuttle, this is done using the cable 34 whose free end will be transported to the barge and fixed to the tip of the pinch of the support assembly of the ends of the hoses and pulled into the trumpet 32 with the winch 33. Of course the unwinding process of the hoses can be controlled, automatically, by appropriate control devices on the barge and / or shuttle.

Thanks to the use of the dynamic positioning system, allowing a lateral shift positioning of the barge and substantially parallel thereto, the invention eliminates the formidable risk of known transfer systems. These are designed to ensure the loading operations, for example in oil, shuttles by providing a positioning of the shuttle and barge in tandem. The shuttle is slaved to keep its longitudinal axis pointed towards the stern of the barge while being connected to it by a hawser.

Even if the shuttle is equipped with a dynamic positioning system, when the shuttle is unduly on the barge, the shuttle operators must try to regain control of the ship, in manual mode, to avoid the collision . But the important inertia of the shuttles makes these maneuvers too long to avoid the collision. As has been described above, the invention proposes another transfer configuration using the possibilities of the dynamic positioning of the ship to no longer point the longitudinal axis of the shuttle to the stern of the barge, but to maintain its position. course essentially identical to the heading of the barge and with a lateral shift. In the event of a failure of the dynamic positioning system, the proposed configuration makes it possible to minimize the risk of collision since the shuttle is no longer slaved towards the barge but laterally offset and parallel thereto. By further equipping the transfer device, for example at the end of the flexible side shuttle, means of emergency disconnection, particularly advantageous in the case of transfer of liquefied natural gas, an accidental movement of the shuttle relative to the barge is not problematic, even in the case of flexible having a relatively short length.

Of course, many modifications can be made to the transfer system of the invention as shown by way of example in the figures. For example, it would be possible, for the storage of hoses, instead of wheels, long terminals, supported by towers mounted on the barge, the type described in French patent FR 2824529, provided to maintain the placement of the shuttle in a position laterally offset from the barge and substantially parallel to the axis thereof, so that during an accidental movement of the shuttle a frontal collision of the latter and the barge can be excluded. To avoid that a lateral contact between the shuttle and the barge can produce significant damage, it is possible to provide on the edge of the barge, which is opposite the shuttle, defense elements 40 such as compressible boxes. As for the hoses, they extend in aerial chains as described, but, if necessary, also in underwater or floating chains.

Claims

A method of transferring fluids between a first vessel, called a barge, and a second vessel, called a shuttle, by which the shuttle is positioned a predetermined distance from the barge and passes at least one flexible transfer conduit therefrom. fluid shuttle, characterized in that the shuttle (2) is placed in a position in which the shuttle is laterally offset from the barge (1) while being oriented substantially parallel to the longitudinal axis of the barge and that a fluid transfer system (7, 9, 28) is provided, which allows a large displacement of the shuttle in the lateral and longitudinal directions, relative to the barge, during a transfer.

2. Method according to claim 1, characterized in that cryogenic hoses (7) for the transfer of liquefied natural gas, which extend in a chain between their ends connected respectively to the barge, are used as flexible transfer ducts ( 1) and the shuttle (2).

3. System for implementing the method according to one of the preceding claims, characterized in that the barge (1) carries a device (9) for storing at least one flexible conduit (7) may be a cryogenic hose at least the duct outlet mechanism is rotatable about a vertical axis and that the receiving device (28) of the duct connector (17) provided on the shuttle (2) is also rotating around a vertical axis, to allow the conduit to extend in any circumstance of transfer of a fluid in a chain between these two suspended ends.

4. System according to claim 3, characterized in that the storage device comprises at least one wheel (9) whose rim (11) has a groove storage of a flexible conduit (7) and which is rotatably mounted about a horizontal axis (12) and pivotable about a vertical axis, on a support (13, 15).

5. System according to claim 4, characterized in that the storage wheel (9) comprises a device

(22) for guiding and aligning the duct leaving its storage groove in the rim (11) of the wheel, with this groove, during the course of the duct.

6. System according to one of claims 3 to 5, characterized in that the device (28) for receiving a connecting piece (17) of the conduit comprises a head which is rotatably mounted about a vertical axis on a support tower (31).

7. System according to one of claims 1 to 6, characterized in that it comprises two storage wheels

(4) and in that the two connecting ends (17) of the two hoses (7) are mounted on a common support provided with a center pinch (19) oriented parallel to the axes of the connectors of the end pieces, being disposed at above these.

8. System according to claim 7, characterized in that the common support carries a fall brake winch (20).

9. System according to one of claims 7 or 8, characterized in that the device (28) for receiving the common support connecting tips (17) of the two hoses (7) comprises a rotating support head of two devices of connection, each of which comprises two connectors (30) for connecting two connection tips (17).

10. System according to claim 9, characterized in that each device (29) support comprises a receiving member and centering pinoche common (19) of the two ends of the two flexible.

11. System according to claim 10, characterized in that the receiving and centering member is in the form of a trumpet (32) and in that a winch (33) is provided for winding the cable (34) which passes through the trumpet and is intended to be fixed during a transfer to the tip of the pinch.

12. System according to claim 11, characterized in that the support (29) of the connectors comprises a fork (36) of correct angular positioning of the flanges (18) of the end pieces, with the aid of a roller (38) disposed on the support of the tips above the pinoche (19).

13. System according to one of claims 1 to 12, characterized in that a storage wheel (4) has a diameter of between 20 and 50 m.

14. System according to one of claims 1 to 13, characterized in that the shuttle is equipped with a dynamic positioning system and particularly lateral thrusters with automatic control by the automatic positioning system.

15. System according to one of claims 14, characterized in that the fluid transfer device is provided with emergency disconnection means.