EP3532426B1

EP3532426B1 - Rope handling system, vessel provided with such a rope handling system and method of handling synthetic rope

Info

Publication number: EP3532426B1
Application number: EP17792215.0A
Authority: EP
Inventors: Joop Roodenburg
Original assignee: Itrec BV
Current assignee: Huisman Equipment BV
Priority date: 2016-10-25
Filing date: 2017-10-24
Publication date: 2020-08-26
Anticipated expiration: 2037-10-24
Also published as: WO2018080304A1; EP3532426A1; SG11201903499TA; NL2017674B1; CN109890746A

Description

The present invention relates to the field of rope handling, in particular in offshore operations. More specifically, the invention relates to a rope handling system for handling of synthetic rope, comprising: a synthetic rope comprising at least a first and second rope section interconnected by a first connector; and a rope storage device. The invention further relates to a vessel provided with such a rope handling system and a method of handling synthetic rope.
Such a rope handling system is commonly applied in offshore operations, including deepwater lowering operations, mooring, and possibly also lifting operations. The rope reel of the storage device is a tensionless reel. The synthetic rope is e.g. made of ultra-high-molecular-weight polyethylene, such as Deenema, Kevlar or Twaron.
A hoist device such as a crane wire may be used for lowering the synthetic rope, e.g. as described in US 8,235,228 . In alternative embodiments, such as disclosed in WO2010/097426 , traction winches are provided to tension the rope for use in offshore operations.
The deeper the water of the offshore operations, the larger the required length of synthetic rope, resulting in the provision of a connector between a first and second rope section. Handling this connector, having a weight in air of 1000-3000 kg, under water up to 2000 kg, proposes new challenges for the rope handling system.
The aim of the present invention is to provide an improved rope handling system for synthetic rope with such a connector.
According to a first aspect of the invention, the rope storage device comprises:

∘ a first rope reel, having a horizontal spooling axle, onto which at least the length of the first rope section is spooled, and
∘ a level winding mechanism extending across the horizontal spooling axle of the first rope reel to spool in and/ or spool out rope,
characterized in that the rope storage device further comprises
∘ a second rope reel, adjacent and spaced from the first rope reel, onto which at least the length of the second rope section is spooled,
∘ a connector storage space provided between the first and second rope reels, into which the first connector is housed.

The first aspect of the invention also relates to a vessel provided with such a rope handling system, and a method of handling synthetic rope wherein use is made of such a rope handling system.
An advantage of such a rope handling system is that the connector is also spooled onto the rope storage device, as a result of which it is not necessary to interconnect the first and second rope section during spooling and/ or unspooling, e.g. after unwinding the second section. As such, the process of spooling and/or unspooling can be more efficient.
This aspect of the invention in particular relates to connectors, having a weight exceeding 1000kg.
In embodiments, the synthetic rope further comprises a third rope section interconnected to the second rope section by a second rope connector. A rope section commonly has a length of at least 500 metres, e.g. 1000 metres. A synthetic rope of two rope sections may consequently have a length of 2000 metres, and a synthetic rope of three rope section may be as long as 2-3km. Such a length is required for deep water operations.
In advantageous embodiments having a third rope section, the third rope section is spooled onto the first rope section onto the first rope reel, and the second rope connector is housed in the connector storage space. As such, an exemplary method of handling synthetic rope wherein use is made of a rope handling system, comprises the following steps:

spooling the first rope section onto the first rope reel;
housing the first connector in the connector storage space;
spooling the second rope section onto the second rope reel;
housing the second connector in the connector storage space;
spooling the third rope section onto the first rope section on the first rope reel.

In an alternative embodiment, a third rope reel is provided, adjacent and spaced from the second rope reel, onto which at least the length of the third rope section is spooled, and wherein a second connector storage space is provided between the second and third rope reels, into which the second connector is housed.
Embodiments comprising four or even more rope sections are also envisaged.
In embodiments, the rope handling system comprises a hoist device to deploy the synthetic rope. Such a hoist device is for example a crane, comprising a hoist cable or crane wire. This hoist cable can also be used to lower a load, and hence the length of this hoist cable can be added to the length of the synthetic rope. A minimum length of such a cable, generally a steel cable, is 500 - 750 metres. As such, rope sections of 500-750 metres can be lowered successively. A common maximum length of such a cable is 3000 metres. For example in WO2009/048316 a crane comprising a deep water lowering cable of 3000 metres is disclosed.
In possible embodiments, the rope handling system further comprises a connection tool to connect the synthetic rope to a hoist cable. Such a connection tool may e.g. weight 4000-5000 kg.
In an exemplary method of handling synthetic rope wherein use is made of a rope handling system, unspooling comprises the following steps:

unspooling the second rope section from the second rope reel;
unspooling the first connector from the connector storage space;
unspooling the first rope section from the first rope reel.

Advantageously, the first rope section is provided with a fore runner of sufficient length, including safety windings, to control the deployment of this last section.
The rope storage device comprising the first and second rope reel, level winding mechanism and connector storage space is in embodiments supported by a stiff frame.
Advantageously, the first and second rope reel have a common spooling axle. In such embodiments, the level winding mechanism preferably extends across the common spooling axle of the first and second rope reel. Yet alternatively, separate level winding mechanisms are provided for the first and second rope reel.
Preferably, the level winding mechanism or mechanisms comprises individual settings for each reel. In embodiments having a single level winding mechanism, preferably a manual override is provided to handle the cross-over between the first and second rope reel, and to assist in landing the connector and housing it in the connector storage space.
Advantageously, a rope reel comprises a drum between two flanges. In embodiments, the flange of the first rope reel adjacent the connector storage is provided with a slit for the passage of the first rope section, and the flange of the second rope reel adjacent the connector storage is also provided with a slit for the passage of the second rope section. Such slits are advantageously rounded and smooth to avoid damage of the synthetic rope. The slits are preferably elongated and open at the circumference of the flange.
In embodiments, a winch drive is provided for the rope reels. For example motors are provided to drive the rope reel(s), and possibly also motor brakes.
The level winding mechanism extends across the horizontal spooling axle, and comprises a horizontal guide over which a spooling device is movable. The level winding mechanism may be electrically driven, and automatically or manually operated.
In embodiments, a spooling device having a quarter circle shape is provided, leading the synthetic rope from a horizontal unspooling direction to a vertical direction. The synthetic rope is preferably spooled in an under-wound direction onto the rope reel. The spooling device e.g. comprises diabolic rollers designed to support the rope and the connector when passing the spooling device. Advantageously, the spooling device comprises guide plates to assure the connector orientation during passage.
The rope handing system is advantageously provided on an offshore vessel, e.g. a monohull vessel. The synthetic rope can be deployed from the vessel from a board side, or through a moonpool provided in the vessel. It is also conceivable that the vessel is a semi-submersible.
In embodiments, a hang-off device is provided adapted to engage the connector and suspend at least a rope section of the synthetic rope therefrom. Advantageously, the hang-off device is designed to accommodate the connector. Possibly, the hang-off device comprises a catcher to guide the synthetic rope.
In an exemplary method of handling synthetic rope wherein use is made of a rope handling system, deploying a load comprises the following steps:

connecting the second rope section to a hoist cable of a hoist device;
unspooling the second rope section from the second rope reel and lowering the second rope section by the hoist device;
unspooling the first connector from the connector storage space;
engaging the first connector by the hang-off device and suspending the second rope section from the hang-off device,
raising the hoist cable,
connecting the first connector to the hoist cable and disengaging the first connector from the hang-off device
unspooling the first rope section from the first rope reel and lowering the first rope section by the hoist device.

In embodiments of a rope handling system according to the first aspect of the invention, also a transfer assembly to transfer the synthetic rope according to the first or second aspect of the invention is provided.
According to a second aspect of the invention, the rope handling system comprises:

a synthetic rope comprising at least a first and second rope section interconnected by a first connector; and
a rope storage device comprising:
- ∘ a first rope reel, having a horizontal spooling axle, onto which at least the length of the first rope section is spooled, and
- ∘ a level winding mechanism extending across the horizontal spooling axle of the first rope reel to spool in and/ or spool out rope,
wherein the transfer assembly comprises a connector guide trough, supporting the connector as it slides through the trough.

The second aspect of the invention also relates to a vessel provided with such a rope handling system, and a method of handling synthetic rope wherein use is made of such a rope handling system.
An advantage of this aspect of the invention is that the connector, having a weight in air of 1000-3000 kg, underwater up to 2000 kg, can be safely and carefully transferred over horizontal distances. This aspect of the invention in particular relates to connectors, having a weight exceeding 1000kg.
For example, in embodiments wherein the rope storage device is provided at a horizontal distance from a deployment position, e.g. a board side of a vessel, one or more of such connector guide troughs are advantageous.
In embodiments, the trough is provided with a low friction material along the trough to protect the synthetic rope and the connector. For example, the sides and bottom of the trough are provided with coated pads. It is also conceivable that the connector is provided with a low friction material, to assist sliding of the connector as it slides through the trough. Yet alternatively, the trough is provided with rails and the connector with cooperating slides.
The transfer assembly may further comprise additional sheaves and guides. Preferably, guides are provided at the ends of the trough to guide the rope from the trough to the vertical plane. Such guides e.g. comprise roller guides.
The rope storage device advantageously comprises:

a first rope reel, having a horizontal spooling axle, onto which at least the length of the first rope section is spoolable, and
a level winding mechanism extending across the horizontal spooling axle of the first rope reel to spool in and/ or spool out rope.

Advantageously, an end of the guide trough is provided above the level winding mechanism, and a swivelling guide is provided at this end to receive the synthetic rope from the level winding mechanism. In such embodiments, the orientation of the swivelling guide may follow the orientation of the level winding mechanism.
The rope handing system is advantageously provided on an offshore vessel, e.g. a monohull vessel. The synthetic rope can be deployed from the vessel from a board side, or through a moonpool provided in the vessel. It is also conceivable that the vessel is a semi-submersible In embodiments, the connector guide trough is positioned at an elevated position
In embodiments, the rope handing system further comprising a hang-off device adapted to engage the connector and suspend at least a rope section of the synthetic rope therefrom. Advantageously, the hang-off device is designed to accommodate the connector. Possibly, the hang-off device comprises a catcher to guide the synthetic rope.
Advantageously, an end of the guide trough is provided above the hang-off device.
In possible embodiments, an end of the guide trough is provided near the hang-off device and wherein a movable guide is provided at this end of the trough to either allow the connector to engage the hang-off device, or allow the synthetic rope to bypass the hang-off device.
Advantageously, the movable guide is an extendable guide. The movable guide is e.g. movably by means of a hydraulic cylinder.
The rope handing system is advantageously provided on an offshore vessel, e.g. a monohull vessel. The synthetic rope can be deployed from the vessel from a board side, or through a moonpool provided in the vessel. It is also conceivable that the vessel is a semi-submersible. Possibly, the rope storage device is provided below deck. The connector guide trough is possibly provided on deck or at a distance above deck, allowing personnel and equipment to move around deck below the connector guide trough.
In embodiments, the rope handling system comprises a hoist device to deploy the synthetic rope. Such a hoist device is for example a crane, comprising a hoist cable or crane wire. The crane may be provided on deck of a vessel.
A third aspect of the invention relates to a rope handling system for handling of synthetic rope, comprising:

a synthetic rope comprising at least a first and second rope section interconnected by a first connector; and
a rope storage device;
a transfer assembly to transfer the synthetic rope;
a hang-off device, adapted to engage the connector and suspend at least a rope section of the synthetic rope therefrom,

The third aspect of the invention also relates to a vessel provided with such a rope handling system, and a method of handling synthetic rope wherein use is made of such a rope handling system.
The advantage of a movable guide is that a synthetic rope comprising at least a first and second rope section interconnected by a first connector is more easily deployable as the movable guide enables an easy switch between lowering the synthetic rope and engaging the connector.
In embodiments, the guide is extendable by a hydraulic cylinder, e.g. provided on deck of a vessel.
The advantage is in particular evident in view of an exemplary method of handling synthetic rope wherein use is made of a rope handling system, wherein deploying a load comprises the following steps:

According to this method, between the steps of lowering the second and first rope section, the connector has to be engaged by the hang-off device.
With a movable guide an advantageous method of handling synthetic rope comprising at least a first and second rope section interconnected by a first connector comprises the steps of:

positioning a movable guide provided near a hang-off device in a position allowing the synthetic rope to bypass the hang-off device;
connecting the second rope section to a hoist cable of a hoist device;
unspooling the second rope section from the second rope reel and lowering the second rope section by the hoist device, thereby bypassing a hang-off device;
unspooling the first connector from the connector storage space;
moving the movable guide in a position allowing the connector to engage the hang-off device;
engaging the first connector by the hang-off device and suspending the second rope section from the hang-off device,
raising the hoist cable,
connecting the first connector to the hoist cable and disengaging the first connector from the hang-off device
positioning the movable guide in the position allowing the synthetic rope to bypass the hang-off device
unspooling the first rope section from the first rope reel and lowering the first rope section by the hoist device.

Aspects of the invention can be provided separately or in combination.
The invention will be explained further in relation to the drawings, in which:

Fig. 1 is a top view of part of a vessel provided with a crane and a rope handling system according to the present invention;
Fig. 2 shows a side view of a hoisting crane adapted to deploy the synthetic rope;
Fig. 3 shows in a perspective view a rope handling system according to the first and second aspect of the invention;
Figs. 4a and 4b show in side views the rope handling system of fig. 3;
Fig. 5 shows schematically a rope handling system of figs. 3, 4a and 4b;
Fig. 6 shows schematically a rope handling system according to the second aspect of the invention;
Figs. 7a and 7b show an exemplary connector of a rope handing system according to the aspects of the invention;
Fig. 8 shows a hang-off device of an embodiment of a rope handling system according to the aspects of the invention;
Figs. 9a, 9b and 9c show in a side view subsequent steps of a method of lowering a load.

In fig. 1 a top view of part of a vessel 1 is shown, which is suitable, inter alia, for deploying a synthetic rope on the seabed. Obviously the vessel could also be of a different type, e.g. a semi-submersible. The vessel could also be a platform, such as a tension leg platform or otherwise. The vessel 1 has a hull 3 with a deck 2, a crane 20 and a rope handling system 100. Here, the rope handling system 100 is provided at a deck 2. At a board side of the hull 3 of the vessel, the synthetic rope is allowed to be lowered.
An exemplary embodiment of a crane 20 adapted to lower the synthetic rope is shown in fig. 2
In this embodiment the hoisting crane is disposed in the vicinity of the same side of the hull as the rope handling system 100, which hoisting crane 20 has a vertical structure fixed to the hull 2. The hoisting crane 20 will be described in more detail below.
The hoisting crane 20, which is illustrated in detail in figure 2, has a substantially hollow vertical column 21 with a foot 22, which in this case is fixed to the hull 3 of the vessel 1. Furthermore, the column 21 has a top 23.
The hoisting crane 20 has a jib 24. An annular bearing structure extends around the vertical column 21 and guides and carries a jib connection member 28, so that the jib connection member 28, and therefore the jib 24, can rotate about the column 21.
In this case, the jib connection member 28 forms a substantially horizontal pivot axis, so that the jib 24 can also be pivoted up and down. There is at least one drive motor 27 for displacing the jib connection member 26 along the annular bearing structure. To pivot the jib 24 up and down, there is a topping winch 30 provided with a topping cable 31 which engages on the jib 24.
Furthermore, the hoisting crane 20 comprises a hoisting winch 35 for raising and lowering a load, with an associated hoisting cable 36 and a hoisting hook 37.
The hoisting crane 20 further comprises a deep water winch 82 and an associated deep water cable 81 for raising and lowering a load. In the shown embodiment the deep water cable 81 is guided via a lower cable pulley assembly 83. Preferably, such deep water winch and cable allow the lowering of subsea structures to water depths of at least 1000 meters, more preferably up to 3000 meters. The lifting capacity of such a hoisting crane 20 may e.g. be 400.000 kg in waterdepths from 0-3000 metres. With the rope handling system of the present invention, the lifting capacity may be extended e.g. to 190.000 kg in waterdepths up to 6000 metres.
Such deep water winch and deep water cable may preferably be embodied as an abandonment and recovery (A&R) winch and cable. Such A&R winch and cable is used in pipe lay operations to be able to abandon and recover a previously launched pipeline. For such purposes, it is required that the entire weight of the previously launched pipeline is suspended from an A&R wire.
At the top 23 of the column 21 there is a top cable guide 40 provided with a cable pulley assembly 41 for the topping cable 31, and with a cable pulley assembly 42 for the hoisting cable 36, and with a cable pulley assembly 80 for the deep water cable 81.
One or more cable pulley assemblies 43 for the hoisting cable 36 and/or the deep water cable 36 and a cable pulley assembly 44 for the topping cable 31 are arranged on the jib 24. The number of cable parts for each cable can be selected as appropriate by the person skilled in the art.
The winches 30 and 35 are in this case disposed in the foot 22 of the vertical column 21, so that the topping cable 31 and the hoisting cable 36 extend from the associated winch 30, 35 upward, through the hollow vertical column 21 to the top cable guide 40 and then towards the cable guides 43, 44 on the jib 24.
The top cable guide 40 has a rotary bearing structure, for example with one or more running tracks around the top of the column 21 and running wheels, engaging on the running tracks, of a structural part on which the cable pulley assemblies are mounted. As a result, the top cable guide 40 can follow rotary movements of the jib about the vertical column 21 and adopt substantially the same angular position as the jib 24.
The jib winch 31 and the hoisting winch 35 are arranged on a rotatable winch support 50, which is rotatable about a rotation axis substantially parallel with the vertical column 21. The movable winch support 50, which is mounted movably with respect to the vertical column 21. The winch support 50 here is located in the vertical crane structure, preferably in the region of the foot 22 under the circular cross section part of the column 21, and is mechanically decoupled from the top cable guide 40. The support 50 could e.g. also be arranged in the hull of the vessel below the column, e.g. the foot could have an extension which extends into the hull.
In the example shown, the winch support 50 is a substantially circular platform which at its circumference is mounted in an annular bearing 51, with the winches 31, 35 arranged on the platform. The annular bearing 51 is in this case such that the platform can rotate about a vertical axis which coincides with the axis of rotation of the top cable guide. The bearing can have any appropriate design including trolleys running along a circular track.
The rotatable winch support 50 has an associated drive motor assembly 52 for moving the winch support 50, in such a manner that the winch support 50 maintains a substantially constant orientation with respect to the jib 24 in the event of rotary movements of the jib 24 about the vertical column 21. The orientation of the winch support 50 with respect to the top table guide 40 likewise remains substantially constant, since its movements are once again the consequence of rotary movements of the jib 24.
As visible in fig. 1, the deep water winch 82 is positioned at a distance from the crane 20. Possibly, lower cable pulley assembly 83 is positioned below the movable winch support 50.
Preferably, the deep water winch 82 and associated or integrated storage drum for the deep water cable is positioned in the hold of the vessel. Preferably, the deep water winch and associated or integrated storage drum is positioned as low as possible due to its large weight. The deep water winch 82 and the cable pulley assembly 83 are mounted on a deep water winch support 84, which is preferably mounted in a fixed orientation with respect to the vertical column 21,22.
Alternatively, the deep water winch support is mounted moveable with respect to the vertical column 21, 22. In a possible embodiment, it is envisaged to connect the movable deep water winch support 84 to the movable winch support 50 of the jib winch and the hoisting winch 31, 35, such that the supports 84,50 are movable synchronously.
The associated deep water cable 81 extends from the deep water winch 82 through the rotation axis of the movable winch support, which is in this case through the center of the movable winch support 50, to the top cable guide and then to a hoisting cable guide on the jib.
In the embodiment shown, there is an angle sensor 60 for detecting the position of the component 28 of the jib connection member 26 with respect to the vertical column 21, the drive motor assembly 52 of the winch support 50 having associated control means 53 which are in operative contact with the angle sensor 60.
In figs. 3, 4a and 4b and 5 the rope handling system 100 is shown in further detail. In the drawings, a synthetic rope is shown comprising a first rope section 101 and second rope section 102 interconnected by a first connector 103. Also a third rope section 105 is schematically shown, interconnected to the second rope section 102 by a second rope connector 104.
The connector 103 is shown in further details in figs. 7a and 7b. Here, it is visible that in the shown embodiment the connector 103 comprises an eyelet 103a, through which a shackle 104 can be inserted. Such a shackle is in particular advantageous when the connector 103 is to be engaged by a hang-off device or by a hoist cable, e.g. by a hook of a hoist cable. It is noted that the connector 103 according to the invention has a weight exceeding that of 1000 kg.
In fig. 7b, it is visible that connector 103 comprises a pulley 103b for the second rope section 102 and a pulley 103c for the first rope section 101. A connector comprising such pulleys is advantageous to protect the rope and extend rope life time.
Furthermore, a rope storage device 110 is shown, here below deck 2 in the hull 3 of the vessel. The rope storage device 110 comprises a first rope reel 111, having a horizontal spooling axle 112, onto which at least the length of the first rope section 101 is spooled, and a second rope reel 113, adjacent and spaced from the first rope reel 111, onto which at least the length of the second rope section 102 has been spooled, which is unspooled in figs 3 and 4.. Here, the first and second rope reel have a common spooling axle 112. The rope has been spooled in an under-wound spooling direction. In fig. 5, the third rope section 105 is spooled onto the first rope section 101 onto the first rope reel 111, and the second rope connector is housed in the connector storage space.
A level winding mechanism 120 extends across the horizontal spooling axle 112 of the first and second rope reels to spool in and/or spool out rope. The level winding mechanism 120 comprises a horizontal guide 121 over which a spooling device 122 is movable.
Rope storage device 110, including rope reels 111, 113, connector storage space 114 and level winding mechanism 120 is supported by a frame 118 in the hull 3 of the vessel 1. In particular, the spooling axle 112 is supported by the frame 118.
In the shown embodiment, shown in an enlarged view in fig. 7a, the spooling device 122 has a quarter circle shape, leading the synthetic rope from a horizontal unspooling direction to a vertical direction. The spooling device e.g. comprises diabolic rollers (not visible) designed to support the rope and the connector when passing the spooling device. Here, the spooling device comprises guide plates 122' to assure the orientation of connector 103 during passage.
The rope storage device 110 further comprises a connector storage space 114 provided between the first rope reel 111 and second rope reel 113, into which the first connector 103 was housed.
In the shown embodiment, the rope reels 111, 113 comprise a drum between two flanges. The flange 111a of the first rope reel 111 adjacent the connector storage is provided with a slit 111b for the passage of the first rope section, and the flange 113a of the second rope reel adjacent the connector storage is provided with a slit 113b for the passage of the second rope section.
In figs. 3 and 4, the third rope section 105 has already been unspooled and lowered overboard the vessel 1. A connector 106, here of similar design as the first and second connectors, is provided to connect a load L to the third rope section 106.
The situation in figs. 3 and 4 is during deploying a load L, wherein the following steps have taken place:

connecting connector 106 at the end of the third rope section 105 to a hoist cable of a hoist device;
unspooling the third rope section from the first rope reel 111 and lowering the third rope section by the hoist device;
unspooling the second connector 104 from the connector storage space 114;
engaging the second connector 104 by a hang-off device 200 and suspending the third rope section 105 from the hang-off device 200.

Subsequent steps are:

Hang-off device 200 is shown in detail in fig. 8. It is mounted to the hull 3 of the vessel. Hang-off device 200 is adapted to engage/ accommodate a connector and suspend at least a rope section of the synthetic rope therefrom, thereby transferring the load into the ship's structure.
In figs. 3 and 4, and in detail in fig. 6, a transfer assembly 150 according to a second aspect of the invention is shown. The transfer assembly 150 comprises a connector guide trough 151, supporting the connector as it slides through the trough.
In the shown embodiment, the sides and bottom of the trough are provided with pads 151a, 151b, 151c with a low friction material, to protect the synthetic rope and the connector.
An end 151y of the guide trough is provided above the level winding mechanism 120. The transfer assembly 150 further comprise additional guides. Here, guides 152, 153 are provided at ends 151y, 151x respectively of the trough 151 to guide the rope from the trough to the vertical plane. Guide 152, as visible in fig. 3, comprises roller guides.
Guide 152 is a swivelling guide, visible in fig 4a, to accommodate the spooling angle of the rope departing from the level winding mechanism 120.
In the shown embodiment, the end 151x of the guide trough 151 is provided near the hang-off device 200. Preferably a movable, e.g. extendable guide 153 is provided at this end of the trough 151 to either allow the connector to engage the hang-off device, or allow the synthetic rope to bypass the hang-off device. In particular, the guide 153 is able to extend further outboard to keep the synthetic rope free from the hang-off device 200 during lowering or retrieving empty rope. The transition is advantageously done by a hydraulic cylinder, operated from deck.
In figs. 9a and 9b in a side view subsequent steps of a method of lowering a load are shown, wherein use is made of a rope handling system. The rope handling system is similar to that shown in figs. 3-8, and hence same parts have been given same reference numerals. A different type of crane 50 is shown to lower the synthetic rope, similar to the crane described in WO20141014343 and WO2016159762 of the same applicant.
Crane 50 comprises a hoist cable 55 with a hook 60, adapted to be attached to a connector of the synthetic rope. In fig. 9a it is visible that the hook 60 has been attached to both a load L and connector 106 at an end of the third rope section 105. The load can be picked up from deck by the hook 60, and slewed overboard by the crane 50, the third rope section 106 of the synthetic rope following the crane movement. This third rope section 106 is positioned in the guide trough 151.
In fig. 9a, the movable guide 153 is provided at an extended position, further outboard to keep the synthetic rope free from the hang-off device 200. Advantageously, the crane is provided with heave compensation during lowering of the load. Now crane 50 lowers the rope section 105.
Once connector 104 has been unspooled and reached the hang-off device 200, movable guide 153 is provided closer to the vessel to allow engagement of connector 104 by the hang-off device. The hook 60 can be released from the connector 106 and raised by the crane to engage connector 104.
The movable guide 153 is subsequently moved to the extended position to allow lowering of rope section 102 by the crane 50. Once connector 103 has been unspooled, the movable guide 153 is provided closer to the vessel, allowing the connector 103 to engage the hang-off device 200.
In fig. 9b, the third rope section 105, second connector 104 and rope section 102 have been unspooled from the connector storage space. For example, a hydraulic cylinder (not visible) is provided to alter the position of the guide 153. This situation resembles that of fig. 4b, except that here connector 103 is engaged instead of connector 104.
Once hang-off, the load is transferred from the crane 50 to the synthetic rope. The hook 60 has been released from connector 104, e.g. by an ROV. The empty hook has been retrieved to the surface by crane 50. Now, as visible in fig. 9b, the crane hook 60 is reconnected to the connector 103 to transfer the load back to the crane hook, and lower the load L further with the crane hook 60.
Subsequently, connector 103 is lowered, and rope section 101. As visible in fig. 9c, in this embodiment a connector 109 is attached to the end of rope section 101 opposite the end of connector 103. This connector 109 can also be engaged by the hang-off device 200, allowing hook 60 of the crane to be disconnected from connector 103 and connected to connector 109. Subsequently, the load L can be lowered further by the crane 50, with the length of hoist cable 55. This hoist cable can measure another 3000 metres, lowering load L in the shown situation to a depth of 6000 metres in total: 1000 metres with each rope section 105, 102, 101 plus the hoist cable 55.

Claims

Rope handling system (100) for handling of synthetic rope, comprising:
- a synthetic rope comprising at least a first rope section (101) and second rope section (102) interconnected by a first connector (103); and

- a rope storage device (110) comprising:
∘ a first rope reel (111), having a horizontal spooling axle (112), onto which at least the length of the first rope section (101) is spooled, and

∘ a level winding mechanism (120) extending across the horizontal spooling axle of the first rope reel to spool in and/ or spool out rope,
characterized in that the rope storage device further comprises

∘ a second rope reel (113), adjacent and spaced from the first rope reel (111), onto which at least the length of the second rope section (102) is spooled,

∘ a connector storage space (114) provided between the first and second rope reels, into which the first connector is housed.
Rope handing system according to claim 1, wherein the synthetic rope further comprises a third rope section (105) interconnected to the second rope section by a second rope connector (104), wherein preferably the third rope section (105) is spooled onto the first rope section onto the first rope reel, and wherein the second rope connector is housed in the connector storage space.
Rope handing system according to claim 1, wherein the first and second rope reel have a common spooling axle (112), wherein preferably the level winding mechanism (120) extends across the common spooling axle (112) of the first and second rope reel.
Rope handing system according to claim 1, wherein a rope reel comprises a drum between two flanges, and wherein the flange (111a) of the first rope reel (111) adjacent the connector storage (114) is provided with a slit (111b) for the passage of the first rope section (101), and wherein the flange (113a) of the second rope reel (113) adjacent the connector storage is provided with a slit (113b) for the passage of the second rope section (102).
Rope handing system according to claim 1, further comprising a hoist device (20) to deploy the synthetic rope, preferably further comprising a hang-off device (200) adapted to engage the connector and suspend at least a rope section of the synthetic rope therefrom.
Rope handling system (100) for handling of synthetic rope, comprising:
- a synthetic rope comprising at least a first rope section (101) and second rope section (102) interconnected by a first connector (103); and

- a rope storage device (110);

- a transfer assembly (150) to transfer the synthetic rope;
characterized in that the transfer assembly comprises a connector guide trough (151), supporting the connector (103, 104) as it slides through the trough, wherein preferably the trough is provided with a low friction material (151a, 151b, 151c) along the trough to protect the synthetic rope and the connector.
Rope handing system according to claim 6, wherein the rope storage device comprises:
- a first rope reel (111), having a horizontal spooling axle (114), onto which at least the length of the first rope section is spoolable, and

- a level winding mechanism (120) extending across the horizontal spooling axle of the first rope reel (111) to spool in and/ or spool out rope
, wherein preferably an end (151y) of the guide trough is provided above the level winding mechanism and wherein a swivelling guide is provided at this end to receive the synthetic rope from the level winding mechanism (120).
Rope handing system according claim 6, further comprising a hang-off device (200) adapted to engage the connector and suspend at least a rope section of the synthetic rope therefrom.
Rope handing system according to the preceding claim, wherein an end (151x) of the guide trough is provided near the hang-off device and wherein a movable, e.g. extendable guide is provided at this end of the trough to either allow the connector to engage the hang-off device, or allow the synthetic rope to bypass the hang-off device.
Rope handing system according to claim 6, further comprising a hoist device (20) to deploy the synthetic rope.
Rope handling system for handling of synthetic rope, comprising:
- a synthetic rope comprising at least a first rope section (101) and second rope section (102) interconnected by a first connector (103); and

- a rope storage device (110);

- a transfer assembly (150) to transfer the synthetic rope;

- a hang-off device (200), adapted to engage the connector and suspend at least a rope section of the synthetic rope therefrom,
characterized in that
the transfer assembly comprises a movable, e.g. extendable guide (153) provided near the hang-off device to either allow the connector to engage the hang-off device, or allow the synthetic rope to bypass the hang-off device.
Rope handing system according to claim 11, wherein the guide is extendable by a hydraulic cylinder, e.g. provided on deck of a vessel.
Vessel (1) provided with a rope handling system (100) according to any of the preceding claims.
Method of handling synthetic rope wherein use is made of a rope handling system according to one or more of the preceding claims.
Method of handling synthetic rope comprising at least a first rope section (101) and a second rope section (102) interconnected by a first connector (103); comprising the steps of
- positioning a movable guide (153) provided near a hang-off device (200) in a position allowing the synthetic rope to bypass the hang-off device;

- connecting the second rope section (102) to a hoist cable (55) of a hoist device (20);

- unspooling the second rope section from a second rope reel (113) and lowering the second rope section by the hoist device, thereby bypassing the hang-off device;

- unspooling the first connector from a connector storage space (114);

- moving the movable guide in a position allowing the connector to engage the hang-off device;

- engaging the first connector by the hang-off device and suspending the second rope section from the hang-off device,

- raising the hoist cable;

- connecting the first connector to the hoist cable and disengaging the first connector from the hang-off device;

- positioning the movable guide in the position allowing the synthetic rope to bypass the hang-off device;

- unspooling the first rope section from a first rope reel (111) and lowering the first rope section by the hoist device.