A slip rope arrangement

Abstract

It is described a system (1) for preventing damage to a floating loading hose (18) during cargo transfer, wherein the system (1) comprises: a tank vessel (20) comprising a tank vessel manifold (23) and a winch (24); a cargo transfer vessel (10); a floating loading hose (18) providing fluid communication between the tank 5 vessel manifold (23) and the cargo transfer vessel (10); a guiding line (25) having a guiding line length (LL), a first guiding line end (25f) and a second guiding line end (25s). The first guiding line end (25f) is connected to the floating loading hose (18) and the second guiding line end (25s) is connected to the winch (24). The winch (24) is configured to reel in the guiding line (25) thereby reducing the guiding line 10 length (LL). It is further described a method for preventing damage to a floating loading hose (18) during cargo transfer between a cargo transfer vessel (10) and a tank vessel (20).

Description

[0001] TITLE: A SLIP ROPE ARRANGEMENT

[0002] TECHNICAL FIELD

[0003] The present invention relates to a system for preventing damage to a floating loading hose during cargo transfer. The present invention also relates to a method for preventing damage to a floating loading hose during cargo transfer.

[0004] BACKGROUND

[0005] Some floating production storage and offloading (FPSO) units are deployed a considerable distance away from shore making transport of oil and gas by pipeline not an economically viable option. A common approach is therefore to store the oil temporarily on board the FPSO and load it onto a tanker for transport to its final destination or customer. Traditionally, that has been done using shuttle tankers that transport the oil to a harbour close by where the oil is transferred to a conventional tanker that transport the oil to its final destination. This operation involves operating a large tanker during cargo transfer from the FPSO with considerable CO2 emissions. Further, it requires the transfer of the cargo from a shuttle tanker to a conventional tanker with the environmental risk associated with such an operation. The FPSO unit is kept stationary by mooring lines relative to the wells on the seabed.

[0006] Recently, a new concept for cargo transfer was introduced. Here, a so-called Cargo Transfer Vessel (CTV) is employed, that keeps a traditional tanker on station and transfers the oil from the FPSO directly to the tanker. CTVs have a flexible operational profile and can handle different sizes of tankers, ranging from a Suezmax to a very large crude oil carrier (VLCC). These vessels have significant difference in size.

[0007] Cargo transfer operations usually take many hours to complete. During this time the CTV and the tanker are facing the elements, that is waves, currents and winds that act on them. The CTV is equipped with a dynamic navigation or positioning system that keeps the CTV on the designated station while the tanker is weathervaning and following the prevailing weather. Prevailing weather is the resulting force tensor for wind, wind generated waves, swell and surface current seen by a vessel. Due to safety considerations, the CTV is to be kept downwind or downstream of the FPSO. A floating loading hose connects the CTV and the tanker. The floating loading hose orients itself according to surface currents. Surface currents can have a different direction to the prevailing weather seen by the tanker. This may lead to situationswhere the floating loading hose can cross the bow of the tanker, leading to significant damage of the floating hose and potentially compromising the integrity of the floating hose.

[0008] It is intention of the claimed invention, to address some of the above challenges.

[0009] SUMMARY OF THE INVENTION

[0010] The present invention is directed to a solution that may solve or at least reduce at least one of the aforementioned problems or challenges.

[0011] The invention is defined in the attached claims. The invention is specified in the independent claims whereas advantageous adaptations and versions of the invention is specified in the dependent claims.

[0012] In accordance with a first aspect of the invention it is described a system for preventing damage to a floating loading hose during cargo transfer, wherein the system comprises:

[0013] - a tank vessel comprising a tank vessel manifold and a winch,

[0014] - a cargo transfer vessel,

[0015] - a floating loading hose providing fluid communication between the tank vessel manifold and the cargo transfer vessel,

[0016] - a guiding line having a guiding line length, a first guiding line end and a second guiding line end,

[0017] wherein the first guiding line end is connected to the floating loading hose and the second guiding line end is connected to the winch,

[0018] wherein the winch is configured to reel in the guiding line thereby reducing the guiding line length.

[0019] Cargo transfer may be transfer of a fluid.

[0020] The fluid may be hydrocarbons. The hydrocarbons may be oil.

[0021] Alternatively, the fluid may be ammonia. The ammonia may be in liquid or gaseous form.

[0022] Cargo transfer may thus be transfer of fluids from a floating production storage and offloading (FPSO) unit, via the cargo transfer vessel (CTV), and to the tank vessel to a tank vessel.

[0023] The system may comprise a tug, and the tug may be configured to connect to a tank vessel stern of the tank vessel via a tug towing line and apply a pulling force to the tank vessel in a direction away from the cargo transfer vessel.

[0024] Consequently, the tug assists in stabilizing the tank vessel stem.The tug may apply a pulling force to the tank vessel to provide sufficient damping control to avoid any oscillation, or fish tailing, of the tank vessel.

[0025] The tank vessel may be any tanker, such as a very large crude carrier (VLCC), a Suezmax tanker, or an Aframax tanker.

[0026] The floating loading hose may comprise a first floating loading hose end, a second floating loading hose end and an intermediate floating loading hose connection point positioned between the first floating loading hose end and the second floating loading hose end, and

[0027] wherein the first floating loading hose end may be connected to the tank vessel manifold and the second floating loading hose end may be connected to the cargo transfer vessel, and

[0028] wherein the intermediate floating loading hose connection point may be connected to the first guiding line end.

[0029] The floating loading hose may have a constant floating loading hose length.

[0030] The floating loading hose length is preferably independent of a size of the tank vessel.

[0031] The floating loading hose length may be chosen according to the largest expected tank vessel. The largest expected tank vessel may be a very large crude oil carrier, VLCC, and the floating loading hose length may allow loading of the very large crude oil carrier, VLCC, sized tank vessel.

[0032] The winch may be arranged on the tank vessel, aft of the tank vessel manifold. The winch may be an aft spring winch.

[0033] The cargo transfer vessel may comprise one or more mooring winches, and the tank vessel may comprise a tank vessel bow, and

[0034] wherein the system may comprise a towing line having a first towing line end, a second towing line end and a towing line length,

[0035] wherein one of the mooring winches may be connected to the first towing line end and the second towing line end may be connected to the tank vessel bow.

[0036] During cargo transfer, the towing line length is kept constant such that the distance between the cargo transfer vessel and the tank vessel is kept constant.

[0037] The cargo transfer vessel may comprise a reel with a reel drum and an emergency release mechanism,

[0038] wherein the floating loading hose may be reelable on to and off the reel drum, and wherein the second floating loading hose end may be connected to the emergency release mechanism.The floating loading hose is fully reeled off the reel during cargo transfer such that the emergency release mechanism can disconnect the floating loading hose instantly thereby providing a safe cargo transfer operation.

[0039] The emergency release mechanism may be arranged inside the reel drum, on the surface of the reel drum or close to the reel drum.

[0040] In accordance with a second aspect of the invention it is described a method for preventing damage to a floating loading hose during cargo transfer between a cargo transfer vessel and a tank vessel,

[0041] wherein the cargo transfer vessel has a cargo transfer vessel stern and the tank vessel has a tank vessel bow, and

[0042] wherein the floating loading hose extends between the cargo transfer vessel and the tank vessel,

[0043] wherein the floating loading hose comprises a first floating loading hose end, a second floating loading hose end and an intermediate floating loading hose connection point positioned between the first floating loading hose end and the second floating loading hose end,

[0044] wherein the tank vessel comprises a winch and a guiding line,

[0045] wherein the guiding line is connected to the intermediate floating loading hose connection point and the winch,

[0046] wherein the method comprises:

[0047] - observing an inter vessel space between the cargo transfer vessel stern and the tank vessel bow,

[0048] - checking whether the floating loading hose has crossed from a first side to a second side of an inter vessel space symmetry line extending between the cargo transfer vessel stem and the tank vessel bow, and

[0049] if the floating loading hose has crossed to the second side:

[0050] - operating the winch to reel in the guiding line thereby reducing the guiding line length to move the floating loading hose from the second side to the first side, and

[0051] - continuing to observe the inter vessel space,

[0052] or

[0053] if the floating loading hose is on the first side:

[0054] - continuing to observe the inter vessel space.

[0055] The guiding line length may be adjusted with the winch.

[0056] By operating the winch to reduce the guiding line length, the intermediate floating loading hose connection point is moved closer to the winch.

[0057] By operating the winch to reduce the guiding line length, at least parts of the floating loading hose are moved closer to a tank vessel stern of the tank vessel.The guiding line may comprise a first guiding line end and a second guiding line end and the tank vessel may comprise a tank vessel manifold,

[0058] wherein the method comprises, before the step of observing the inter vessel space, the steps of:

[0059] - attaching the first guiding line end to the intermediate floating loading hose connection point,

[0060] - securing the second guiding line end to the second floating loading hose end, - transporting the second floating loading hose end to the tank vessel,

[0061] - connecting the second floating loading hose end to the tank vessel manifold, - connecting the second guiding line end to the winch.

[0062] Chafing protection may be provided to the guiding line running through a fairlead of the tank vessel.

[0063] The above-described system and method for preventing damage to a floating loading hose during cargo transfer between a cargo transfer vessel and a tank vessel may have one or more of the following advantages:

[0064] • It requires no additional crew or vessels to control the position of the floating loading hose, thus keeping the carbon footprint of the cargo transfer operation(s) unchanged,

[0065] • Allowing the CTV to interact with all sizes of tank vessels, yet maintaining the same level of safety for all cargo transfer operations,

[0066] • Always being able to reel out the full floating loading hose thus providing the same level of safety and ability to disconnect in an emergency,

[0067] • Providing a solution to control the position of the floating loading hose which can be adopted to different wind, current and wave directions and velocities.

[0068] Above-discussed preferred and / or optional features of each aspect of the invention / disclosure may be used, alone or in appropriate combination, in the other aspects of the invention / disclosure.

[0069] DESCRIPTION OF THE DRAWINGS

[0070] Following drawings are appended to facilitate the understanding of the claimed invention:

[0071] Fig. 1 - illustrates a plan view of a system for preventing damage to a floating loading hose during cargo transfer with a tank vessel, a cargo transfer vessel and a guiding line,Fig. 2 - illustrates a plan view of the system in Fig. 1 with an additional tug, Fig. 3a, b - illustrates a plan view of the system in Fig. 1 with different size tank vessel (3a: VLCC; 3b: Suezmax),

[0072] Fig. 4 - illustrates how the floating loading hose of the system in Figs. l-3a,3b is connected to the cargo transfer vessel, tank vessel and the winch,

[0073] Fig. 5 - illustrates the arrangement of a mooring winch and towing line of the system in Figs. 1-4,

[0074] Fig. 6 - illustrates a plan view of a reel for the floating loading hose on the cargo transfer vessel,

[0075] Fig. 7 - illustrates a plan view of the system, where a prevailing weather and surface current are aligned,

[0076] Fig. 8 - illustrates a plan view of the system, where the prevailing weather and surface current are not aligned and the floating loading hose is in front of the tank vessel,

[0077] Fig. 9 - illustrates a plan view of the system of Fig. 8, where the length of the guiding line has been shortened compared to Fig. 8 and the floating loading hose has been moved away from the bow.

[0078] DETAILED DESCRIPTION

[0079] In the following, one or more specific embodiments of the invention will be described in more detail with reference to the drawings. However, it is specifically intended that the invention is not limited to the embodiments and illustrations contained herein but includes modified forms of the embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation- specific decisions must be made to achieve the developer’s specific goals, such as compliance with system and / or business-related constraints, which may vary from one implementation of the invention to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication and manufacture for the skilled person having the benefit of this disclosure. It is clear that features described in relation to the system is equally valid for the method, and vice versa.

[0080] The present invention relates to a system and a method for preventing damage to a floating loading hose during cargo transfer.A system 1 for preventing damage to a floating loading hose 18 during cargo transfer, figures 1 to 3

[0081] Figure 1 discloses a support a system 1 for preventing damage to a floating loading hose 18 during cargo transfer. This system comprises at least two vessels, a tank vessel 20 and a cargo transfer vessel 10. They are in towing configuration during cargo transfer. The tank vessel 20 is in standby with all propulsive power being switched off while the cargo transfer vessel 10 is being controlled and kept on station by a dynamic positioning system.

[0082] The cargo is hydrocarbons, usually crude oil that is pumped from a floating production storage and offloading (FPSO, not shown) unit to the cargo transfer vessel 10 and from the cargo transfer vessel 10 through a floating loading hose 18 to the tank vessel manifold 23 of the tank vessel 20.

[0083] Also shown in figure 1 is the winch 24 on the tank vessel 20. A further component of the system 1 is a guiding line 25. The guiding line 25 is connected at a first guiding line end 25f to the floating loading hose 18 and at a second guiding line end 25s to the winch 24. The winch 24 can reel in the guiding line 25 and thereby reduce the guiding line length LL.

[0084] A further configuration of the system is shown in figure 2 with a tug 8. This tug connects to the tank vessel stern 22 of the tank vessel 20 via tug towing line 9. The tug 8 operates in a direction away from the cargo transfer vessel 10 with the aim to stabilize the tank vessel stem 22, depending on the weather conditions.

[0085] The cargo transfer vessel 10 is designed to work with many different sizes of tank vessels 20, using their onboard equipment. The floating loading hose 18 is stored on board of the cargo transfer vessel 10. When deployed, it connects to the manifold 23 of the tank vessel 20. However, smaller tank vessels 20 are shorter, hence the floating loading hose 18 has a longer “free” length that can free move in the water potentially causing problems. This is illustrated in figure 3a showing the tank vessel 20 in the form of a very large crude oil carrier VLCC. This is the largest type of tank vessel 20 intended to be used with the cargo transfer vessel 10. Hence, there is no excess length of the floating loading hose 18. For a tank vessel 20 in the form of a Suezmax, shown schematically in figure 3b, the floating loading hose 18 is free to float even in front of the tank vessel 20, potentially being damaged by a bulb of tank vessel bow 21b.

[0086] Elements of the system 1 for preventing damage to a floating loading hose 18 during cargo transfer, figures 4 to 6

[0087] In the following, it is described in more detail elements of the system 1 for preventing damage to a floating loading hose 18 during cargo transfer.As shown in figure 4, the floating loading hose 18 comprises a first floating loading hose end 18f connected to the tank vessel manifold 23 and a second floating loading hose end 18s connected to the cargo transfer vessel 10. The floating loading hose 18 further comprises an intermediate floating loading hose connection point 18m positioned between the first floating loading hose end 18f and the second floating loading hose end 18s. The intermediate floating loading hose connection point 18m is connected to the first guiding line end 25f.

[0088] As mentioned earlier, the cargo transfer vessel 10 may connect to different sizes of tank vessels 20. To achieve this without the need for changing the configuration of the cargo transfer vessel 10, the cargo transfer vessel 10 carries only one floating loading hose 18, with a constant floating loading hose length LH which is preferably selected to connect to the largest expected tank vessel 20. This is typically a VLCC.

[0089] Also shown in figure 4 is the winch 24. The purpose of the winch 24 is to receive and handle the guiding line 25 by controlling a guiding line length LL and thereby controlling the position of the floating loading hose 18. The winch 24 is controlled by a crew member of the cargo transfer vessel 10 who is temporarily transferred to the tank vessel 20 for the duration of the cargo transfer operation. Alternatively, the winch 24 may be operated by a crew member of the tank vessel 20, acting on instructions from a crew member of the cargo transfer vessel 10. The winch 24 is part of the existing equipment of the tank vessel 20. The winch 24 is usually positioned aft of the tank vessel manifold 23 and may be an aft spring winch 24. Shown in figure 5 is a mooring winch 16 positioned near a cargo transfer vessel stern 11 of the cargo transfer vessel 10. There may be more than one mooring winch 16 on the cargo transfer vessel 10. The tank vessel 20 comprises a tank vessel bow 21 with a bulb of tank vessel bow 21b. Figure 5 also shows a towing line 17 with a first towing line end 17f connected to the mooring winch 16 and a second towing line end 17s connected to the tank vessel bow 21. The towing line 17 has a towing line length 17L. The towing line length 17L is kept constant during cargo transfer, i.e. the towing line length 17H does not change during cargo transfer.

[0090] As shown in figure 6, the cargo transfer vessel 10 is equipped with a reel 14 near the cargo transfer vessel stern 11. The reel 14 comprises a reel drum 15 and an emergency release mechanism 19. The second floating loading hose end 18s is connected to the emergency release mechanism 19.

[0091] To stop fluid flow in the floating loading hose 18, first the export pumps on the FPSO are stopped (not shown in the figures). The emergency release mechanism 19 comprises a valve that will close in way of the quick release mechanism to avoid any fluid spill of the fluids being left in the floating loading hose 18.The floating loading hose 18 is reeled on to and off the reel drum 15. During cargo transfer, the floating loading hose 18 is fully reeled off the reel 15. This ensures, that during cargo transfer the emergency release mechanism 19 is available and can disconnect the floating loading hose 18 instantly. Hence, a safety disconnect function is provided, independent of the size of the tank vessel 20. The emergency release mechanism 19 may be arranged on the inside the reel drum 15, on the surface of the reel drum 15 or close to the reel drum 15.

[0092] A method for preventing damage to a floating loading hose 18 during cargo transfer, figures 7 to 9

[0093] It is now described a method for preventing damage to a floating loading hose f8 during cargo transfer between a cargo transfer vessel fO and a tank vessel 20.

[0094] The cargo transfer vessel fO has a cargo transfer vessel stern f f and the tank vessel 20 has a tank vessel bow 21, and

[0095] wherein the floating loading hose 18 extends between the cargo transfer vessel 10 and the tank vessel 20,

[0096] wherein the floating loading hose 18 comprises a first floating loading hose end 18f, a second floating loading hose end 18s and an intermediate floating loading hose connection point 18m positioned between the first floating loading hose end 18f and the second floating loading hose end 18s,

[0097] wherein the tank vessel 20 comprises a winch 24 and a guiding line 25, wherein the guiding line 25 is connected to the intermediate floating loading hose connection point 18m and the winch 24.

[0098] The method comprises the steps of:

[0099] - observing an inter vessel space S between the cargo transfer vessel stern 11 and the tank vessel bow 21. This is typically done by a crew member of the cargo transfer vessel 10 that is temporarily transferred to the tank vessel 20 for the duration of the cargo transfer operation.

[0100] - checking whether the floating loading hose 18 has crossed from a first side SLf to a second side SLs of an inter vessel space symmetry line SL. The inter vessel space symmetry line SL extends between the cargo transfer vessel stern 11 and the tank vessel bow 21.

[0101] If the floating loading hose 18 has crossed to the second side SLs as shown in figure 8, the method comprises operating the winch 24 to reel in the guiding line 25 thereby reducing the guiding line length LL to move the floating loading hose 18 from the second side SLs to the first side SLf, shown in figure 9, and continue to observe the inter vessel space S;or, if the floating loading hose 18 is on the first side SLf, as shown in figure 7 and 9, continue to observe the inter vessel space S.

[0102] By operating the winch 24 to reduce the guiding line length LL, the intermediate floating loading hose connection point 18m is moved closer to the winch 24 and at least a part of the floating loading hose 18 is moved closer to a tank vessel stern 22. The heading of the tank vessel 20 is largely determined by the prevailing weather 3. Prevailing weather 3 is the resulting force tensor for wind, wind generated waves, swell and current seen by a vessel. When the tank vessel 20 is empty the wind forces are more important, while when the tank vessel 20 is close to being fully loaded the swell and current are more dominant.

[0103] The floating loading hose 18 orients itself according to surface current 4. Surface current 4 can have a different direction to the prevailing weather 3 seen by the tank vessel 20. Moreover, the floating loading hose 18 is not affected by wind.

[0104] Figure 7 shows the situation, where the surface current 4 and the prevailing weather 3 are heading in the same direction, reducing or removing the need for manipulating the position of the floating loading hose 18.

[0105] However, there are situations where the surface current 4 and the prevailing weather 3 are heading in different directions as shown in figure 8 and 9. As a result, the floating loading hose 18 can cross the tank vessel bow 21, in particular the bulb of the tank vessel bow 21b, leading potentially to significant damage of the floating loading hose 18 and compromising the integrity of the floating loading hose 18. The prevailing weather 3 and surface current 4 are natural phenomena and may change suddenly or unexpectedly. Hence, it is necessary to observe and check the inter vessel space S at regular intervals to register changes in the environmental conditions and start corrective action to move the floating loading hose 18 if or when needed.

[0106] The guiding line 25 comprises a first guiding line end 25f and a second guiding line end 25s, and the tank vessel 20 comprises a tank vessel manifold 23.

[0107] The method may further comprise steps to connect the guiding line 25 and floating loading hose 18 to the tank vessel 20. These steps precede the step of observing the inter vessel space S:

[0108] - attaching the first guiding line end 25f to the intermediate floating loading hose connection point 18m,

[0109] - securing the second guiding line end 25s to the first floating loading hose end 18f, - transporting the first floating loading hose end 18f to the tank vessel 20,

[0110] - connecting the first floating loading hose end 18f to the tank vessel manifold 23, - connecting the second guiding line end 25s to the winch 24.In the preceding description, various aspects of the apparatus and method according to the invention have been described with reference to the illustrative embodiment. For purposes of explanation, specific numbers, systems and configurations were set forth in order to provide a thorough understanding of the apparatus and its workings. However, this description is not intended to be construed in a limiting sense. Various modifications and variations of the illustrative embodiment, as well as other embodiments of the apparatus and method, which are apparent to person skilled in the art to which the disclosed subject-matter pertains, are deemed to lie within the scope of the present invention as defined by the following claims.LIST OF REFERENCE NUMBERS

[0111] 1 - system

[0112] 3 - prevailing weather

[0113] 4 - surface current

[0114] 8 - tug

[0115] 9 - tug towing line

[0116] 10 - cargo transfer vessel

[0117] 11 - cargo transfer vessel stem

[0118] 14 - reel

[0119] 15 - reel drum

[0120] 16 - mooring winch

[0121] 17 - towing line

[0122] 17L - towing line length

[0123] 17f — first towing line end

[0124] 17s - second towing line end

[0125] 18 - floating loading hose

[0126] 18f - first floating loading hose end

[0127] 18m - intermediate floating loading hose connection point 18s - second floating loading hose end

[0128] 19 - emergency release mechanism

[0129] 20 - tank vessel

[0130] 21 - tank vessel bow

[0131] 21b - bulb of tank vessel bow

[0132] 22 - tank vessel stem

[0133] 23 - tank vessel manifold

[0134] 24 - winch

[0135] 25 - guiding line

[0136] 25f - first guiding line end

[0137] 25s - second guiding line end

[0138] LH - floating loading hose length

[0139] LL - guiding line length

[0140] 5 - inter vessel space

[0141] SL - inter vessel space symmetry line

[0142] SLf- first side of the inter vessel space symmetry line SLs - second side of the inter vessel space symmetry line

Claims

CLAIMS1. A system (1) for preventing damage to a floating loading hose (18) during cargo transfer, wherein the system (1) comprises:- a tank vessel (20) comprising a tank vessel manifold (23) and a winch (24), - a cargo transfer vessel (10),- a floating loading hose (18) providing fluid communication between the tank vessel manifold (23) and the cargo transfer vessel (10),- a guiding line (25) having a guiding line length (LL), a first guiding line end (25f) and a second guiding line end (25s),wherein the first guiding line end (25f) is connected to the floating loading hose (18) and the second guiding line end (25s) is connected to the winch (24), wherein the winch (24) is configured to reel in the guiding line (25) thereby reducing the guiding line length (LL).

2. The system (1) according to claim 1, wherein the system (1) comprises a tug (8), wherein the tug (8) is configured to:- connect to a tank vessel stern (22) of the tank vessel (20) via a tug towing line (9), and- apply a pulling force to the tank vessel (20) in a direction away from the cargo transfer vessel (10).

3. The system (1) according to claim 1 or 2, wherein the tank vessel (20) is any of a very large crude carrier, such as a Suezmax tanker, or an Aframax tanker.

4. The system (1) according to any of the previous claims,wherein the floating loading hose (18) comprises a first floating loading hose end (18f) and a second floating loading hose end (18s) and an intermediate floating loading hose connection point (18m) positioned between the first floating loading hose end (18f) and the second floating loading hose end (18s), andwherein the first floating loading hose end (18f) is connected to the tank vessel manifold (23) and the second floating loading hose end (18s) is connected to the cargo transfer vessel (10), andwherein the intermediate floating loading hose connection point (18m) is connected to the first guiding line end (25f).

5. The system (1) according to any one of the previous claims, wherein the floating loading hose (18) has a constant floating loading hose length (LH).

6. The system (1) according to any of the previous claims, wherein the winch (24) is arranged on the tank vessel (20), aft of the tank vessel manifold (23).

7. The system (1) according to any of the previous claims, wherein:- the cargo transfer vessel (10) comprises one or more mooring winches (16), - the tank vessel (20) comprises a tank vessel bow (21), andwherein the system (1) comprises a towing line (17) having a first towing line end (17f), a second towing line end (17s) and a towing line length (17L),wherein one of the mooring winches (16) is connected to the first towing line end (17f) and the second towing line end (17s) is connected to the tank vessel bow (21).

8. The system (1) according to anyone of the previous claim, wherein the cargo transfer vessel (10) comprises a reel (14) with a reel drum (15) and an emergency release mechanism (19),wherein the floating loading hose (18) is reelable on to and off the reel drum (15), wherein the second floating loading hose end (18s) is connected to the emergency release mechanism (19).

9. The system (1) according to claim 8, wherein the emergency release mechanism (19) is arranged inside the reel drum (15), on the surface of the reel drum (15) or close to the reel drum (15).

10. A method for preventing damage to a floating loading hose (18) during cargo transfer between a cargo transfer vessel (10) and a tank vessel (20),wherein the cargo transfer vessel (10) has a cargo transfer vessel stem (11) and the tank vessel (20) has a tank vessel bow (21), andwherein the floating loading hose (18) extends between the cargo transfer vessel (10) and the tank vessel (20),wherein the floating loading hose (18) comprises a first floating loading hose end (18f), a second floating loading hose end (18s) and an intermediate floating loading hose connection point (18m) positioned between the first floating loading hose end (18f) and the second floating loading hose end (18s),wherein the tank vessel (20) comprises a winch (24) and a guiding line (25),15wherein the guiding line (25) is connected to the intermediate floating loading hose connection point (18m) and the winch (24),wherein the method comprises:- observing an inter vessel space (S) between the cargo transfer vessel stem (11) and the tank vessel bow (21),- checking whether the floating loading hose (18) has crossed from a first side (SLf) to a second side (SLs) of an inter vessel space symmetry line (SL) extending between the cargo transfer vessel stern (11) and the tank vessel bow (21), and if the floating loading hose (18) has crossed to the second side (SLs):- operating the winch (24) to reel in the guiding line (25) thereby reducing the guiding line length (LL) to move the floating loading hose (18) from the second side (SLs) to the first side (SLf), and- continuing to observe the inter vessel space (S),orif the floating loading hose (18) is on the first side (SLf):- continuing to observe the inter vessel space (S).

11. The method according to claim 10,wherein the guiding line (25) comprises a first guiding line end (25f) and a second guiding line end (25s) and the tank vessel (20) comprises a tank vessel manifold (23),wherein the method comprises, before the step of observing the inter vessel space (S), the steps of:- attaching the first guiding line end (25f) to the intermediate floating loading hose connection point (18m),- securing the second guiding line end (25s) to the first floating loading hose end (18f),- transporting the first floating loading hose end (18f) to the tank vessel (20), - connecting the first floating loading hose end (18f) to the tank vessel manifold (23),- connecting the second guiding line end (25s) to the winch (24).

Images