GB2555085A

GB2555085A - Mooring method

Info

Publication number: GB2555085A
Application number: GB1617187.8A
Authority: GB
Inventors: Taylor Richard
Original assignee: Flinstone Tech Ltd
Current assignee: Flinstone Tech Ltd
Priority date: 2016-08-01
Filing date: 2016-10-10
Publication date: 2018-04-25
Also published as: GB2553499B; GB201617187D0; GB2555085A8; GB2553499A; GB201613248D0

Abstract

A method of installing a mooring line or mooring line assembly comprising: providing first 25 and second 15 mooring lines, which may comprise ropes, chains, cables or the like. Providing a retention, clamping and/or tensioning device 40 for retaining, clamping and/or tensioning the first and second lines together so as to provide a mooring line assembly. Finally connecting a distal end of one of the mooring lines to an anchor 30a. The connection may be achieved by the end of the mooring line having a male connector and the anchor a female connector able to mate with the male connector on the mooring line. One of the two mooring lines may pass through the retention, clamping and/or tensioning device. A second method of installing a mooring line assembly is disclosed in which a single mooring line is provided which is combined with a retention, clamping and/or tensioning device to provide a mooring line assembly, with the device then connecting directly to an anchor.

Description

(54) Title of the Invention: Mooring method Abstract Title: Mooring method (57) A method of installing a mooring line or mooring line assembly comprising: providing first 25 and second 15 mooring lines, which may comprise ropes, chains, cables or the like. Providing a retention, clamping and/or tensioning device 40 for retaining, clamping and/or tensioning the first and second lines together so as to provide a mooring line assembly. Finally connecting a distal end of one of the mooring lines to an anchor 30a. The connection may be achieved by the end of the mooring line having a male connector and the anchor a female connector able to mate with the male connector on the mooring line. One of the two mooring lines may pass through the retention, clamping and/or tensioning device. A second method of installing a mooring line assembly is disclosed in which a single mooring line is provided which is combined with a retention, clamping and/or tensioning device to provide a mooring line assembly, with the device then connecting directly to an anchor.

The claims were filed later than the filing date but within the period prescribed by Rule 22(1) of the Patents Rules 2007. At least one drawing originally filed was informal and the print reproduced here is taken from a later filed formal copy.

1/16

10 17

Wrap Angle (degrees)	Factor (T2/T1)
0	2.0
10	1.99
20	1.97
30	1.93
40	1.87
45	1.84
50	1.81
60	1.73
70	1.64
80	1.53
90	1.41

Figure 1(c)

2/16

10 17

65b

65a

Figure 2(b)

15b

3/16

10 17

Tensioner in service

Figure 3(a)

Slack(excess) chain

Figure 3(b)

During tensioning from vessel

4/16

10 17

5/16

6/16

10 17

7/16

10 17

L ι

Figure 7(a)

Figure 7(b)

8/16

10 17

Locating a mooring tensioner at a subsea or underwater site or location (1010) o

Connecting the rig to the mooring tensioner (1015)

Moving or pulling-in a first end of the chain to adjust tension in the chain and/or length of the chain (1020)

Figure 8

9/16

10 17

Figure 9

10/16

10 17

111

Figure 10(a)

Figure 10(b)

11/16

Figure 11(a)

10 17

Figure 11(c)

12/16

10 17

13/16

10 17

Figure 14

14/16

10 17

15/16

10 17

Figure 18

16/16

10 17

Seabed

Figure 19

MOORING METHOD

FIELD OF INVENTION

The present invention relates to a method of installing a mooring line, a method of mooring, a mooring line assembly and an apparatus for mooring a structure, e.g. to a floor of a body of water, e.g. an ocean floor, lake floor, river bed, seabed or the like.

BACKGROUND TO INVENTION

Offshore structures, such as floating structures or floating platforms, can be moored by mooring lines. This can include attaching the mooring lines to the structure to be moored and applying a pre-determined tension to each of the mooring lines. The necessary tension can be applied to the mooring lines, e.g. by using winches that may be provided on the structure to be moored. Such winches can be costly and may only be used intermittently, e.g. during the initial mooring of the structure, relocation of the structure and in response to changing conditions at the mooring site. The installation of a winch on each structure to be moored can become cost and/or time intensive.

A coupling apparatus may be used for connecting the mooring lines from the structure to a seabed or the like. The apparatus may include a guide that can direct a free end of a mooring line towards a surface to enable adjustment of the tension in the mooring lines, e.g. by a winch located on a vessel. During tensioning of the mooring line, bending strain can act on the mooring line due it being pulled and bend around the guide of the apparatus. This can lead to increased wear and/or damages of the mooring line and/or apparatus. In order to minimise the strain on the mooring line, the size of the coupling apparatus may be increased to accommodate larger angles for guiding the mooring line towards the surface. However, this can lead to an increased costs and weight of the coupling apparatus.

EP 1 318 072 A2 (DEEPMOOR LIMITED) discloses a floating platform having a mooring line which passes through a coupling apparatus tethered to a suction anchor. The coupling apparatus allows an effective length of the mooring line between a platform and the anchor to be adjusted using a vessel independent of the platform. The vessel pulls the mooring line through the coupling apparatus, reducing the effective length of mooring line, until the floating platform is in a desired position. The coupling apparatus includes a locking device to prevent the effective length of the mooring line from changing once the floating platform is in the desired position.

This background serves only to set a scene to allow a skilled reader to better appreciate the following description. Therefore, none of the above discussion should necessarily be taken as an acknowledgement that that discussion is part of the state of the art or is common general knowledge. One or more aspects/embodiments of the invention may or may not address one or more background issues.

It is an object of at least one embodiment of at least one aspect of the present invention to obviate or at least mitigate at least one of the problems in the prior art.

It is an object of at least one embodiment of at least one aspect of the present invention to provide a technically simple and/or commercially more cost effective method of mooring than in the prior art.

SUMMARY OF INVENTION

According to a first aspect of the present invention there is provided a method of installing a mooring line or mooring line assembly comprising:

providing first and second mooring lines;

providing a retention, clamping and/or tensioning device for retaining, clamping and/or tensioning the first and second lines together so as to provide a mooring line assembly;

connecting a distal end of one of the mooring lines to an anchor.

The mooring line assembly may be referred to as a pre-set mooring line assembly.

Connecting one end of the mooring line to a subsea anchor may be preceded by lowering the mooring line assembly within a body of water.

Advantageously the distal end of the one of the mooring lines comprises a first, e.g. male, connector portion. The anchor may comprise a second (complementary), e.g. female, connector portion, which may mate, e.g. connectably or seacurably, with the first connector portion.

The female connector portion may be provided on one end of a yet further line, another end of the yet further line being connected to the anchor.

A holder may be provided on the anchor to releasably hold the female connector portion, e.g. in a first disposition, e.g. a vertical disposition. This arrangement may facilitate lowering the male connector portion, e.g. vertically, into the female connector portion.

The female connector may be released from the holder if and/or when tension is applied to the yet further line. The other mooring line may pass or be threaded through the retaining, clamping and/or tensioning device.

According to a second aspect of the present invention there is provided a method of mooring, such as offshore mooring, such as mooring of a buoyant structure, the method comprising:

installing a mooring line assembly according to the first aspect of the present invention;

connecting a distal end of the other one of the mooring lines to a/the structure.

The method may also comprise the step of adjusting tension on the mooring line(s), e.g. by putting on an another end of one of the lines, e.g. which end comprises one of the distal ends.

According to a third aspect of the present invention there is provided a method of installing a mooring line assembly comprising:

providing a first mooring line;

providing a retention, clamping and/or tensioning device for retaining, clamping and/or tensioning the first line so as to provide a mooring line assembly;

connecting the retention, clamping and/or tensioning device to an anchor.

Advantageously the retention, clamping and/or tensioning device comprises a first, e.g. male, connector portion. The anchor may comprise a second (complementary), e.g. female connector portion, which may mate, e.g. connectably or securably mate, with the first connector portion.

The female connector may be released from the holder if and/or when tension is applied to the yet further line.

The mooring line may pass or be threaded through the retaining, clamping and/or tensioning device.

According to a fourth aspect of the present invention there is provided a method of mooring, such as offshore mooring, such as mooring of a buoyant structure, the method comprising:

installing a mooring line assembly according to the third aspect of the present invention;

connecting a distal end of the first mooring line to a/the structure.

According to a fifth aspect of the present invention there is provided a mooring line assembly according to the first or third aspects of the present invention.

According to a sixth aspect of the present invention there is provided a mooring system comprising a mooring line assembly according to the fifth aspect of the present invention.

The following statements may apply to any of the foregoing aspects of the present invention.

According to an embodiment of the present invention there is provided (a tensioner) an apparatus, device, e.g. the retention, clamping and/or tensioning device, for mooring a structure, e.g. to a seabed, river or lake bed, ocean floor or the like. The apparatus may be utilised as or comprise an underwater apparatus for mooring a structure or a subsea apparatus for mooring a structure. A structure may be or comprise a structure to be moored or a structure that may be moored, e.g. in use. The apparatus may be configured to permit tensioning of a/one of the/the (first mooring) line(s) coupled and/or connected to a/the structure. A/one of the lines of the first/the (first mooring) line(s) line may be or comprise a mooring line, offshore mooring line, underwater mooring line or subsea mooring line.

The apparatus may comprise a first portion, e.g. for receiving a portion of a/one of the/the (first mooring) line(s) extending from a/the structure.

The apparatus may comprise a guide portion, e.g. for guiding a/the portion of a line received by the first portion. The guide portion may be movably, e.g. pivotably or rotatably, connected or connectable to the first portion.

The apparatus may comprise a second portion, e.g. for connecting or coupling the apparatus to a seabed or a further structure located thereon. The second portion may be movably, e.g. pivotably or rotatably, connected or connectable to the first portion and/or guide portion.

The apparatus may comprise or define an axis, e.g. a rotational axis. The first portion, the second portion and/or the guide portion may be arranged to be movable, e.g. rotatable or pivotable, around or about the axis of the apparatus. In other words, the first portion, the guide portion and/or the second portion may be coaxially arranged relative to each other. The coaxial arrangement of the first portion, guide portion and/or second portion may permit the first portion, guide portion and/or second portion to be aligned relative to each other during pull-in and/or tensioning a line, e.g. a line or a portion thereof, which may be received in or threaded through the apparatus or a portion thereof, e.g. in use. This may reduce out of plane strain acting on the apparatus and/or a line, e.g. in use, e.g. during pull-in and/or tensioning of a line, e.g. a line or a portion thereof, which may be received in or threaded through the apparatus or a portion thereof. This may lead to a reduction of losses, e.g. due to friction between a line under tension and the apparatus, e.g. during pull-in and/or tensioning of a line. It other words, the coaxial arrangement may facilitate pull-in and/or tensioning of a line.

The apparatus may comprise a line engaging device or chain stopper. The line engaging device may be or comprised in a chain stopper or means for engaging a chain. The line engaging device may be or comprise a means for engaging a chain as described in WO 2015/150770 (by the present Applicant), the content of which is hereby incorporated by reference. The line engaging device may be configured to permit movement of a/one of the/the (first mooring) line(s), e.g. a line or a portion thereof, which may be received in or threaded through the apparatus, in a first direction relative to the apparatus, e.g. in a direction towards the guide portion. The line engaging device may be configured to prohibit movement of a/one of the/the (first mooring) line(s), e.g. a line or a portion thereof, which may be received or threaded through the apparatus, in a second direction relative to the apparatus, e.g. in a direction towards a structure. The line engaging device may be movably connected or connectable to the first portion. For example, the line engaging device may be connected to the first portion so that the line engaging device may be moveable, e.g. rotatable or privotable and/or slidable, relative to the first portion.

The line engaging device may be connected or connectable to the first portion to be movable, actuatable and/or operable between a first position and a second position. The line engaging device may be configured to be moveable, operable and/or actuatable from the first position to the second position, e.g. when tension is applied to at least one end, e.g. a free end, or at least two ends, e.g. a free end and a distal end, of a/one of the/the (first mooring) line(s), e.g. a line or a portion thereof, which may be received in or threaded through the apparatus. The line engaging device may be configured to be moveable, operable and/or actuatable from the second position to the first position, e.g. when tension is released from at least one end, e.g. a free end, of a/one of the/the (first mooring) line(s), e.g. a line or a portion thereof, which may be received in or threaded through the apparatus. For example, in use, a distal end of a/one of the/the (first mooring) line(s), which may be connected or connectable to a structure may be tensioned or be under tension.

The apparatus may be or be configured to be operable, moveable and/or actuatable between a first configuration and a second configuration. In the first configuration of the apparatus, the line engaging device may be in the first position. In the second configuration of the apparatus, the line engaging device may be in the second position. In the first configuration of the apparatus, the first and second portions may be arranged relative to each other such that a longitudinal axis of the first portion may be substantially in line, collinear or coaxial with a longitudinal axis of the second portion. The apparatus may be configured or arranged such that in the first configuration of the apparatus, a/the longitudinal axis of the apparatus may be substantially in line, collinear or coaxial with a longitudinal axis of a line or a portion thereof extending from a structure. The apparatus may be configured or arranged such that in the first configuration of the apparatus the axis may be substantially co-planar with a longitudinal axis of a/one of the/the (first mooring) line(s) or portion thereof extending from a structure and/or the axis extends in a direction substantially perpendicular to a longitudinal axis of a line or portion thereof extending from a structure. In the first configuration of the apparatus, out of plane strain acting on the apparatus and/or a line may be reduced.

In the first configuration, the line engaging means may be configured to engage or be engageable with a/one of the/the (first mooring) line(s) or portion thereof, e.g. to prevent movement of a/one of the/the (first mooring) line(s) in the second direction.

In the second configuration of the apparatus, the first portion and second portion may be arranged relative to each other such that a/the longitudinal axis of the first portion may extend at an angle relative to a/the longitudinal axis of the second portion. The apparatus may be configured such that in the second configuration of the apparatus a/the longitudinal axis of the first portion extends at an angle, e.g. an acute angle, relative to a longitudinal axis of a/one of the/the (first mooring) line(s) or portion thereof extending from a structure. This may reduce out of plane strain acting on the apparatus and/or a/one of the/the (first mooring) line(s) e.g. in use, e.g. during pull-in and/or tensioning of a/one of the/the (first mooring) line(s), e.g. a/one of the/the (first mooring) line(s) or a portion thereof, which may be received in or threaded through the apparatus or a portion thereof. This may lead to a reduction of losses, e.g. due to friction between a line under tension and the apparatus, e.g. during pull-in and/or tensioning of a/one of the/the (first mooring) line(s).

In the second configuration, the line engaging means may be configured to disengage or be disengageable, e.g. partially or fully disengage or be disengageable, from a/one of the/the (first mooring) line(s) or portion thereof, e.g. to prohibit movement of a/one of the/the (first mooring) line(s) or portion thereof in the first direction.

The apparatus may be configured or arranged, e.g. the guide portion may be connected or connectable to the first portion, such that the axis of the apparatus may extend in a direction substantially perpendicular to a/the longitudinal axis of the first portion. The apparatus may be configured or arranged, e.g. the guide portion may be connected or connectable to the first portion, such that a/the longitudinal axis of the first portion may intersect the axis of the apparatus.

The second portion may be configured to receive, mount and/or support a mounting element of a/one of the/the (first mooring) line(s), e.g. a mounting element connected to at least one end, e.g. a free end, of a/one of the/the (first mooring) line(s), e.g. a/one of the/the (first mooring) line(s) or a portion thereof, which may be received in or threaded through the apparatus. For example, the second portion may mount a mounting element of a/the line, when tension on at least one end of a line is released. This may permit secure parking or holding of an end of a/one of the/the (first mooring) line(s), e.g. a free end of a line.

The second portion may be configured to align a mounting element connected to at least one end, e.g. a free end, of a/one of the/the (first mooring) line(s), e.g. a/one of the/the (first mooring) line(s) or a portion thereof, which may be received in or threaded through the apparatus, relative to the apparatus. The second portion may be configured to align at least one end, e.g. a free end, of a/one of the/the (first mooring) line(s), e.g. a/one of the/the (first mooring) line(s) or a portion thereof, which may be received in or threaded through the apparatus, relative to the apparatus. This may maintain a/one of the/the (first mooring) line(s) or an end of a line, e.g. a free end of a/one of the/the (first mooring) line(s), in alignment relative to the apparatus. For example in cases where the line may be or comprise a chain, the configuration of the second portion may prevent misalignment or bending of parts of a chain. This may reduce strain, damage and/or wear of a line/chain. The configuration of the second portion may facilitate connection of a wire, e.g. work wire, to a line, e.g. a mounting element of a line, e.g. during a pull-in and/or tensioning process.

The apparatus may comprise a groove or recess and/or a protrusion. The groove or recess and/or protrusion may be part of or comprised in the second portion. The groove or recess and/or protrusion may be shaped for mounting and/or supporting a mounting element of a/one of the/the (first mooring) line(s), e.g. a mounting element connected to at least one end, e.g. a free end, of a/one of the/the (first mooring) line(s), e.g. a/one of the/the (first mooring) line(s) or a portion thereof, which may be received in or threaded through the apparatus. The groove or recess and/or protrusion may be arranged and/or shaped to cooperate with a further protrusion of a mounting element, e.g. a mounting element connected to at least one end, e.g. a free end, of a/one of the/the (first mooring) line(s), e.g. a/one of the/the (first mooring) line(s) or a portion thereof, which may be received in or threaded through the apparatus, e.g. to enable mounting of a mounting element on the apparatus, e.g. the second portion.

In an embodiment the apparatus may comprise a first connector portion. The first connector portion may be part of or comprised in the second portion. The first connector portion may be (provided) for complementary mating with a corresponding second connector portion. The first connector portion may be part of or comprised in a subsea or underwater connector, e.g. a subsea or underwater mooring connector. The first connector portion may be moveably, e.g. rotatably or pivotably, connected or connectable to the second portion.

In an embodiment the second portion may be configured to connect or couple the apparatus to another line or a portion thereof e.g. a line extending from a seabed or a further structure located thereon. The second portion may be configured to be moveably, e.g. rotatably or pivotably, connected or connectable to another line or a portion thereof, e.g. a line extending from a seabed, e.g. a/the and/or a further structure located thereon.

According to an embodiment of the present invention there may be provided a system for mooring a structure. The mooring system may comprise an apparatus for mooring a structure. The apparatus may be or comprise an apparatus for mooring a structure according to the sixth aspect of the present invention.

The system may comprise a/one of the/the (first mooring) line(s). The/one of the/the (first mooring) line(s) may be or comprise a mooring line, offshore mooring line, underwater mooring line or subsea mooring line. A portion of the line may be threaded or threadable through the apparatus, e.g. in use. The line may be or comprise a chain, wire or rope or the like. A first end, e.g. a distal end, of the line may be configured to be connected or connectable to a structure. The structure may be part of or comprised in the system. The structure may be or comprise a floating structure, offshore structure, vessel, floating platform, subsea structure, underwater structure or buoy.

The line may comprise a second end, e.g. a free end. The second end of the line may be configured to be connected or connectable to a mounting element. The mounting element may be part of or comprised in the system and/or line. The mounting element may be configured to be mounted or mountable on or to the second portion of the apparatus. The mounting element comprises a further protrusion. The further protrusion may be configured, arranged and/or shaped to cooperate with a/the groove and/or protrusion of the second portion of the apparatus, e.g. to enable mounting of the mounting element on or to the apparatus. The further protrusion may be configured, arranged and/or shaped to cooperate with a/the groove and/or protrusion of the apparatus, e.g. the second portion of the apparatus, e.g. to enable alignment of the mounting element and/or the second end of the line relative to the apparatus, e.g. the second portion of the apparatus.

The system may comprise another/the one of the line(s). The other/the one of the line(s) may be or comprise another mooring line, offshore mooring line, underwater mooring line or subsea mooring line. A first end of the other/the one of the line(s) may be configured to be connected or connectable to a seabed, e.g. to an/the anchor or a further structure located thereon. A second end of the other/the one of the line(s) may be configured to be connected, coupled, coupleable or connectable to the second portion of the apparatus.

The system comprises a connector. The connector may be or comprise a mooring connector, underwater mooring connector or subsea mooring connector. The connector may be or comprise a subsea connector as described in WO 2013/186553 (by the present Applicant), the content of which is hereby incorporated by reference. A first connector portion may be configured to be connected or connectable to the apparatus, e.g. the second portion of the apparatus. A second connector portion may be configured to be connected or connectable to a seabed, e.g. to an anchor, or a further structure located thereon. The first portion of the connector may be configured for complementary mating with the second portion of the connector.

According to an embodiment of the present invention there is provided a method for mooring a structure. The method may comprise providing a mooring line assembly according to the fifth aspect and/or a mooring system according to the sixth aspect.

The method may comprise connecting or coupling the assembly to a seabed, e.g. an anchor, or a further structure located thereon.

The method may comprise locating the assembly at a site or location e.g. a subsea or underwater site or location. The method may comprise (thereafter) connecting the structure to the assembly or a portion thereof. The step of connecting may comprise connecting the first end, e.g. the distal end, of a/one of the/the (first mooring) line(s) to the structure and/or threading the second end, e.g. the free end, of the line through the apparatus.

The method may thereafter comprise adjusting and/or varying a tension in a/one of the/the (first mooring) line(s). The method may comprise applying tension to the second end of the line, e.g. by moving or pulling-in of the second end of the line or a yet further line connected to the second end of a/one of the/the (first mooring) line(s).

The method may comprise moving or pulling the second end of a/one of the/the (first mooring) line(s)or a/the yet further line connected to the second end of the line, e.g. to adjust tension in the line and/or length of the line or a portion of the line extending between the apparatus and the structure, e.g. by using a pulling and/or tensioning arrangement, e.g. a winch and/or motor or the like, or an Remotely Operated Vehicle (ROV). The pulling or tensioning arrangement may be provided on a yet further structure, e.g. a vessel, floating platform, offshore structure or the like. The step of moving or pulling the first end of a/one of the/the (first mooring) line(s)may comprise moving, actuating and/or operating the apparatus from first configuration into the second configuration.

According to an embodiment of the present invention there is provided a portion, e.g. for use in an apparatus for mooring a structure and/or a system for mooring a structure. The apparatus may be or comprise an apparatus for mooring a structure. The system may be or comprise a system for mooring a structure. The portion may be configured to receive, support and/or mount a mounting element of a line. The portion may comprise any features of the second portion of the apparatus hereinbefore disclosed.

According to another embodiment of the present invention there is provided a mounting element of a line. The mounting element may be configured to be mounted or for mounting on a portion, e.g. of an apparatus for mooring a structure.

It should be understood that the features defined above in accordance with any aspect of the present invention or below in relation to any specific embodiment of the invention may be utilised, either alone or in combination with any other defined feature, in any other aspect or embodiment of the invention.

BRIEF DESCRIPTION OF DRAWINGS

These and other aspects of the present invention will now be described, byway of example only, with reference to the accompanying drawings, which are:

Figures 1(a) and 1(b)

Figure 1(c)

Figure 2(a)

Figure 2(b)

Figure 3(a)

Figure 3(b)

Figure 4(a)

Figure 4(b)

Figure 4(c) schematic views of a system for mooring a structure according to one or more described example(s); a table of a wrap angle and tension factor; an isometric view of an apparatus for mooring a structure according to one or more described example(s); a part-sectional view of the apparatus in Figure 2(a); an isometric view of the apparatus of Figure 2(a) in a first configuration of the apparatus;

an isometric view of the apparatus of Figure 2(a) in a second configuration of the apparatus;

a side view of the apparatus of Figure 2(a) in the first configuration in which a first portion of the apparatus is shown as effectively transparent;

a side view of the apparatus of Figure 2(a) in the second configuration in which the first portion of the apparatus is shown as effectively transparent;

a part cutaway view of the apparatus of Figure 2(a) in the second configuration in which a part of the first portion of the apparatus is shown as effectively transparent;

Figures 5(a) and 5(b)

Figures 6(a) and 6(b)

Figures 7(a) and 7(b)

Figure 8

Figure 9

Figure 10

Figures 11(a) to (c)

Figure 12

Figures 13 to 16

Figure 17 Figures 18 and 19 isometric views of the apparatus for mooring a structure according to another described example(s); isometric views of the apparatus of Figure 5(a) connected to a further structure on seabed;

isometric views of the further structure on seabed of Figure 6(b) on a seabed;

a flow diagram of a method for mooring a structure according to one or more described example(s);

an anchor for use in a method of installing a mooring line according to an embodiment of the present invention; a mooring line assembly used in the method of installing a mooring line of Figure 1;

a series of views showing the mooring line assembly of Figure 2 being deployed to the anchor of Figure 1; a view of the mooring line assembly of Figure 10 connected to the anchor of Figure 9;

steps in a method of mooring according to an embodiment of the present invention;

a modification to the method of Figures 13 to 16; and further steps in the method of mooring of Figures 13 to 16.

DETAILED DESCRIPTION OF DRAWINGS

An exemplary system 5 for mooring a structure is shown in Figures 1(a) and 1(b). The system 5 comprises an apparatus for mooring a structure. The apparatus may be configured to permit tensioning of a line, such as a mooring line, offshore mooring line, underwater mooring line or subsea mooring line or the like, connected to the structure. The apparatus may be provided in the form of a mooring tensioner 10 and the line may be provided in the form of a chain 15. It will be appreciated that in other examples the line may be provided in the form of a rope, synthetic, e.g. polyester, wire or the like. A first end, e.g. a distal end, 15a of the chain 15 is connected to the structure, which in this example is provided in the form of a floating platform or rig 20. It will be appreciated that in other examples, the structure may be a floating structure, offshore structure, vessel, plat form, subsea structure, underwater structure or buoy, such a submersible buoy, semisubmersible buoy or submerged turret production buoy or submerged turret loading buoy, or the like.

In the example of Figure 1(a) and 1(b), a portion 15b of the chain 15 is threaded through the mooring tensioner 10 and guided towards a vessel 22. A second end, e.g.

a free end, 15c of the chain 15 is shown as being coupled to the vessel 22 and/or a pulling or tensioning arrangement, such as a winch and/or motor or the like, for adjustment of a tension and/or length of the chain 15.

As can be seen in the exemplary mooring tensioner 10 shown in Figure 1(b), a first end 25a of a further mooring line 25 can be connected to the mooring tensioner, while the second end 25b of the further mooring line 25 is connected to a seabed 30, e.g. to a further structure 30a located on the seabed 30. The further structure 30a may be provided in the form of a drag embedment anchor, vertically loaded anchor, driven pile, suction pile, suction anchor, suction embedded plate anchor or other types of anchors or structures. It will be appreciated that in other examples the mooring tensioner may be directed connected/connectable to the seabed 30 and/or the further structure 30a located thereon.

An exemplary mooring tensioner 10 is shown in Figures 1(b), 2(a) to 6(b). The mooring tensioner 10 comprises a first portion 35 for receiving the portion 15b of the chain 15 that extends from the rig 20 to the mooring tensioner 10. The exemplary mooring tensioner 10 comprises a guide portion for guiding the portion 15b of the chain 15 received by the first portion 35. The guide portion may be provided in the form of a chain wheel or sheave 40. In this example the chain wheel or sheave 40 is a five pocket chain wheel. It will be appreciated that in other examples other wheels, such as wheels without any pockets or a more or less than five pockets, may be utilised as a guide portion. The chain wheel 40 is movably connected, such as rotatably or pivotably connected, to the first portion 35. The mooring tensioner 10 includes a second portion 45 for connecting or coupling the mooring tensioner 10 to the seabed 30 and/or the further structure 30a located thereon. It will be appreciated that the second portion 45 may be configured to connect the mooring tensioner 10 directly or indirectly to the seabed 30 and/or the further structure 30a located thereon, as will be described below. The second portion 45 is movably connected, such as pivotably or rotatably connected, to the first portion 35 and/or the chain wheel 40.

The mooring tensioner 10 has an axis A (see Figure 2(b), which may be provided in the form of a rotational axis A. The axis A may be provided by an elongate member, which may be in the form of a first load pin or pin 47. The first portion 35, the second portion 45 and/or the chain wheel 40 are arranged to be movable, such as rotatable or pivotable, around or about the axis A, e.g. the pin 47, of the mooring tensioner 10. In other words, the first portion 35, the chain wheel 40 and/or the second portion 45 are coaxially arranged relative to each other. The coaxial arrangement of the first portion 35, chain wheel 40 and/or second portion 45 may permit the first portion 35, chain wheel 40 and/or second portion 45 to be aligned relative to each other during pull-in/tensioning of the chain 15, e.g. by the pulling and/or tensioning arrangement. This may reduce out of plane strain acting on the mooring tensioner 10 and the chain 15, e.g. during pulling-in/tensioning of the chain 15.

Referring back to Figures 1(a) to 1(c), tension T2 acting on the further mooring line can be greater than tension T1 on the chain 15, which may be applied by or due to the vessel 22 and/or the rig 20. The extent to which the load/tensioning from the vessel 22 can be increased can depend of a wrap angle Θ of the chain 15 around the chain wheel 40. As can be seen from the table in Figure 1(c), the factor of the tensions T2/T1 applied to the mooring tensioner 10 decreases with increasing wrap angle Θ of the chain around the chain wheel 40. . This may lead to a reduction in the tension that needs to be applied from the vessel in order to generate the required pre-tension in the mooring line and/or may allow smaller, more readily available and/or cheaper vessels to be used.

The exemplary mooring tensioner 10 shown in Figures 1(b) to 6(b) has a line engaging device, which may be provided in the form of a chain stopper 50. The chain stopper 50 may comprise one or more features of the chain engaging means disclosed in WO 2015/150770 (by the present applicant), which is hereby incorporated by reference. The chain stopper 50 can be configured to permit movement of the chain 15 a portion thereof in a first direction relative to the mooring tensioner 10, e.g. in a direction towards the chain wheel 45. The chain stopper 50 can be configured to prohibit movement of the chain 15 or a portion thereof in a second direction relative to the mooring tensioner 10, e.g. in a direction towards the rig 20. Th chain stopper 50 may be or act as a one-way ratchet or the like.

The chain stopper 50 is movably connected to the first portion 35. For example, the chain stopper 50 is connected to the first portion 35 so that chain stopper 50 is rotatable or privotable and/or slidable relative to the first portion 35. As can be seen in Figures 4(a) to 4(c), the chain stopper 50 is rotatably or pivotably connected to the first portion 35 at a first attachment region 35a, e.g. by a second elongate member, which may be provided in the form of a second pin or load pin 55a. The chain stopper 50 is slidably connected to the first portion 35 at a second attachment region 35b, e.g. by a third elongate member, which may be provided in form of a third pin or load pin 55b The chain stopper 50 includes a slot 60 provided in the chain stopper 50 through which the third pin extends. It will be appreciated that in other examples the slot may be provided in the first portion of the mooring tensioner additionally to or instead of the slot in the chain stopper.

The chain stopper 50 is connected to the first portion 35 to be moveable between a first position, shown in Figures 3(a) and 4(a), and a second position, shown in Figures 3(b) and 4(b). In the first position of the chain stopper 50, the third pin 55b is located at a first end 60a of the slot 60. In the second position of the chain stopper 50, the third pin 55b is located at a second end 60b of the slot 60. When tension is applied to the second end 15c of the chain 15, e.g. by the pulling and/or tensioning arrangement on the vessel 22, the chain stopper 50 is configured to move from the first position to the second position. In other words, due to the applied tension to the second end 15c of the chain 15, the third pin 55b moves from the first end 60a of the slot 60 towards the second end 60b of the slot 60. Tension may additionally act on the first end 15a of the chain 15 due to its connection to the rig 20.

When the tension is released at the second end 15c of the chain 15, the chain stopper 50 is configured to move or return to the first position. In other words, due to the release of tension at the second end 15c of the chain 15, the third pin 55b moves or returns from the second end 60b of the slot 60 towards the first end 60a of the slot 60.

The mooring tensioner 10 can be configured to be operable, moveable and/or actuatable between a first configuration and a second configuration. In the first configuration of the mooring tensioner 10, the chain stopper 50 is in the first position, as shown in Figures 3(a) and 4(a). In the second configuration of the mooring tensioner 10, the chain stopper 50 is in the second position, as shown in Figures 3(b) and 4(b).

As can be seen in the examples shown in Figures 3(a) and 4(a), in the first configuration of the mooring tensioner 10, the first portion 35 and the second portion 45 are arranged relative to each other such that a longitudinal axis B’ of the first portion 35 is substantially in line, collinear or coaxial with a longitudinal axis B” of the second portion 45. The mooring tensioner 10 can be configured such that in the first configuration of the mooring tensioner, a/the longitudinal axis B of the mooring tensioner 10 is substantially in line, collinear or coaxial with a longitudinal axis C of the second end 15c of the chain 15.

Additionally or alternatively, the mooring tensioner 10 can be configured such that in the first configuration of the mooring tensioner 10, the axis A of the mooring tensioner 10 is be substantially co-planar with the longitudinal axis C of the second end 15a of the chain 15 and/or the axis a of the mooring tensioner 10 extends in a direction substantially perpendicular to the longitudinal axis C of the first end 15a of the chain 15. In the first configuration of the mooring tensioner 10, out of plane strain acting on the mooring tensioner 10 and/or the chain 15 may be reduced.

In the first configuration, the chain stopper 50 or a portion thereof can be configured to engage or be engageable with the chain 15 or portion thereof, e.g. to prevent movement of the chain 15 in the second direction.

Referring to Figures 3(b) and 4(b), in the second configuration of the mooring tensioner 10, the first portion 35 and second portion 45 are arranged relative to each other such that the longitudinal axis of the first portion B’ extends at an angle a, which may be an acute angle, relative to the longitudinal axis B” of the second portion 45. The mooring tensioner 10 may be configured such that in the second configuration, the longitudinal axis B’ of the first portion 35 extends at an angle β, e.g. an acute angle, relative to the longitudinal axis C of the second end 15c of the chain 15, as shown in Figure 4(b). This may reduce out of plane strain acting on the mooring tensioner and/or the chain e.g. in use, e.g. during pull-in and/or tensioning of the chain 15. This may lead to a reduction of losses, e.g. due to friction between the chain under tension and the mooring tensioner, e.g. during pull-in and/or tensioning of the chain.

In the second configuration, the chain stopper 50 means can be configured to partially disengage or be disengageable from the chain 15 or portion thereof, e.g. to prohibit movement of chain 15 or portion thereof in the first direction.

As can be seen in the examples shown in Figures 1(b) to 4(b) the chain wheel 40 is be connected or connectable to the first portion 35 such that the axis A of the mooring tensioner 10 extends in a direction substantially perpendicular to the longitudinal axis B’ of the first portion 35 and the longitudinal axis B’ of the first portion 35 intersect the axis A, e.g. the first pin 47, of the mooring tensioner 10.

Referring to Figures 2(a), 3(a) and 3(b), the second portion 45 can be configured to receive, mount and/or support a mounting element 65, which is connected to the second end 15c of the chain 15. For example, the second portion 45 can mount a mounting element of the chain 15, when tension on the second end 15c of the chain 15 is released. The second end 15c of the chain 15 may become slack, i.e. non-tensioned, as shown in Figure 3(a). The mounting element 65 may permit secure parking or holding of an end of the chain 15 and/or prevent the end of the chain 15 from disengaging from or passing through the mooring tensioner 10. In other words, the mounting element 65 may act as a stopper to prevent the second end of the chain 15c from passing through the mooring tensioner 10. The mounting element 65 may facilitate access to an end of the chain 15 for subsequent tensioning of the chain 15. Additionally or alternatively, the mounting element 65 may negate the use of buoyancy element, which may be difficult to install.

The second portion 45 can be configured to align the mounting element 65 and/or the second end 15c of the chain 15 relative to the mooring tensioner 10, e.g. the second portion 45. This may maintain the chain 15 and/or the second end 15c of the chain 15 in alignment relative to the apparatus. The configuration of the mooring tensioner 10, e.g. second portion 45, may prevent misalignment or bending of parts,

e.g. one or more link(s), of the chain 15. This may reduce strain acting of, damage and/or wear of the chain 15.

Referring to Figures 2(a), 3(a) and 3(b), the mooring tensioner 10, e.g. the second portion 45 includes a groove or recess 45a and/or a protrusion 45b. In this example the second portion 45 comprises a pair of oppositely arranged grooves or recesses 45a and/or a pair of oppositely arranged protrusions 45b. It will be appreciated that in other examples there may be provided less than two or more than two grooves or recesses and/or protrusions. The grooves or recesses 45a and/or protrusions 45b are shaped for mounting and/or supporting the mounting element 65. The grooves or recesses 45a and/or protrusions 45b are arranged and/or shaped to cooperate with a further protrusion 65a of a mounting element 65, e.g. to enable mounting of the mounting element 65 on the mooring tensioner 10, e.g. the second portion 45.

The mounting element 65 is configured to permit connecting of the mounting element 65 and/or the second end 15c of the chain 15 to a yet further line (not shown), which may be in the form of a wire, e.g. a work wire, rope or the like. For example, in use the yet further line is connected to the pulling and/or tensioning arrangement on the vessel. Tension is applied to the yet further line, e.g. using the pulling and/or tensioning arrangement generates tension, e.g. tension T1 in the work wire and T2 in the mooring line, as for example shown in Figure 1(a). For examples, the mounting element 65 may have a connection element 65b, which may be provided in the form of a pad eye or the like.

Referring to Figures 5(a) to 7(b), the mooring tensioner 10 can comprise a first connector portion 70. In this example the first connector portion 70 is part of the second portion 45 and is moveably connected thereto. The first connector portion 70 can be provided for complementary mating with a corresponding second connector portion 75. The first and second connector portions 70, 75 are part of a subsea or underwater connector, e.g. a subsea or underwater mooring connector. An example of such a connector is disclosed in WO 2013/186553 (by the present Applicant), the content of which is hereby incorporated by reference. The second connector portion 75 is configured to be connected or connectable to the further structure 30a located on the seabed 30. The second connector portion 75 may be configured to moveably connected to the further structure 30a, e.g. by a first connection arrangement 80. The first connection arrangement 80 may be provided in the form of a joint or uni-joint arrangement and/or be configured to permit rotational movement of the second connector portion 75, e.g. in at least one direction, relative to the further structure 30a. A first part 80a of the first connection arrangement may be part of the second connector portion 75 and another part 80b of the first connection arrangement may be part of the further structure 30a. The connection arrangement 80 may be configured to be operated or switchable between a first configuration, in which the first part 80a of the connection arrangement 80 is maintained in stationary position, e.g. as shown in Figure 6(a), and a second configuration, in which the first part 80a of the connection arrangement 80 and/or the mooring tensioner 10 or a portion thereof is permitted to move relative to the second part 80b of the connection arrangement 80 and/or the further structure 30a, e.g. as shown in Figure 6(b). The first part 80a of the connection arrangement 80 may be maintained in a stationary position by one or more locking element(s) 90. For example, in use, removal of the one or more locking elements permits movement of the first part 80a of the connection arrangement 80 and/or the mooring tensioner 10 or a portion thereof relative to the second part 80b of the connection arrangement 80 and/or the further structure 30a.

In the examples shown in Figures 5(a) to 6(b), the first connector portion 70 is provided in the form of a male part 70a and the second connector portion 75 is provided in the form of a female part 75a. The female part 75a is configured for receiving the male part 70a. The male part 70a is lowered towards the female part 75a to enable connection of the male part 70a to the female part 75a. During the lowering of the male part 70a into the female part 75a, the male part 70a may be aligned, such as rotationally aligned, relative to the female part 75a. Once the male and female parts 70a, 75a are aligned relative to each other, the male part 70a can be fully inserted into the female part 75a and secured to the female part 75a by a yet further elongate member, which may be provided in the form of a fourth load pin or pin 85.

Referring back to the exemplary system 5 shown in Figures 2(a), 3(a) and 3(b), the second portion 45 can be configured to connect the mooring tensioner 10 to the further mooring line 25, which in turn is connected to the seabed 30 and/or the further structure 30a located thereon. The second portion 45 can be configured to be moveably connected to the further mooring line 25 or a portion thereof. For example, the system 5 can include a second connection arrangement 95 for moveably connecting the mooring tensioner 10, e.g. the second portion 45, to the further mooring line 25.

Figure 8 shows a flow diagram of an exemplary method for mooring a structure. As described above, the structure may be provided as a rig 20. The method can comprise the step of providing the mooring tensioner 10 and/or the system 5. In step (1010), the mooring tensioner 10 is located at a site or location e.g. a subsea or underwater site or location. Subsequent to locating the mooring tensioner 10, the mooring tensioner 10 is connected to the rig 20, e.g. threading the chain 15 through the mooring tensioner 10 and connecting the first end 15a of the chain 15 to the rig 20.

The method can comprise the step of connecting or coupling the mooring tensioner 10 to the seabed 30 or a further structure 30a located thereon. This may be done by utilising the further mooring line 25 to connect, e.g. indirectly connect, the mooring tensioner 10 to the seabed 30 and/or a further structure 30a located thereon. In some examples the mooring tensioner 10 may be connected, e.g. directly connected, the seabed 30 and/or a further structure 30a located thereon, by utilising the connector or mooring connector, e.g. first and second connector portions 70, 75.

In step 1020 the method includes moving or pulling-in the second end 15c of the chain 15 to adjust tension in the chain 15 and/or length the chain 15 or a portion of the chain 15 extending between the mooring tensioner 10 and the rig 20, e.g. using a pulling or tensioning arrangement, e.g. a winch and/or motor or the like, or an Remotely Operated Vehicle (ROV). As described above, the yet further line may be connected to the second end 15c of the chain 15, e.g. the mounting element 65, and/or tension can be applied to the yet further line, e.g. by the pulling and/or tensioning arrangement on the vessel 22. The step of moving or pulling second end 15c of the chain 15 can include moving, actuating and/or operating the mooring tensioner 10 from first configuration into the second configuration.

There will now be described a method of installing a mooring line or mooring line assembly according to the present invention. There will also be described a method of mooring, such as offshore mooring, e.g. of a buoyant structure.

An installation sequence for a mooring line assembly or subsea tensioner according to the present invention is as follows. An anchor 101 is installed with one half (female) of a subsea mooring connector 102. In Figure 1 this is shown as suction pile anchor, but the installation method is suitable for other anchor types. A length of chain 103 connects the half of the mooring connector 102) which should be kept above the seabed to a padeye 104 located in a beneficial location on the pile in order to maximise load holding capacity.

A mooring line is deployed from an Anchor Handling Vessel (AHV) or other suitable construction vessel as shown in Figure 10. At a bottom of the mooring line is a male half of the subsea mooring connector 105. The female half 102 is located on the pre-installed anchor 101. Above the male mooring connector 105 is a length of chain 106 sufficient to keep the more easily damaged wire or polyester rope section of the mooring line 107 clear of the seabed during the mooring systems service life. Above the wire/polyester rope there is a short length of chain 108 leading to a tensioner apparatus 109. Pre-installed into the tensioner 109 is sufficient length of chain 110 to adjust the tension of the mooring system accordingly. Above this length of chain 110 there is further wire or polyester rope 111. The length of chain 110 passes through the chain stopper of the tensioner (the chain flapper is secured in the down position), partially around the wheel of the tensioner where such is held in place with a pin 112. The length of chain 110 terminates with a rope sling 113 or other suitable lifting gear to allow later connection of the AHV work wire to chain 110 for the purpose of tensioning the mooring line.

It should be noted that the above description covers one possible mooring line configuration. However, it will be appreciated that the tensioner can be positioned in any location in the mooring line above the male subsea mooring connector 105. For instance, chains 106 and 108 may be one short length of chain, rope 107, may be removed and rope 111 longer, such that the tensioner 109 would now be located closer to the anchor 101. This may be of benefit in positioning the tensioner (109) at sufficient depth to prevent marine growth that could foul the mechanism of the flapper. The use of a subsea mooring connector 102,105 provides flexibility and technical and/or commercial advantage.

With the mooring line deployed from the installation vessel as described above, the line is positioned to allow the male mooring connector 105 at the end of the mooring line to be lowered into the female mooring connector 102 mounted on the suction pile. The procedure for installing the male mooring connector into the female and connecting the two halves, is described in detail in GB 2 517 873 B (by the present Applicant)

With the Subsea Mooring Connector (SMC) fully connected, the SMC can be lifted from the deployment frame incorporated into the suction pile fabrication and laid onto the seabed. At this point it may be suitable to connect a buoyancy module (114) to the top end of the mooring line and to lower the buoyancy module into the water with the mooring line suspended below it. This would allow the mooring system to be preset prior to the arrival on location of a buoyant structure, e.g. a floating platform, to be moored. This would reduce the amount of time between arrival on location of the floating platform and the platform being tethered in a safe condition. This pre-set mooring line assembly with buoyancy module is as shown in Figure 12.

When the floating platform is present on location and ready to be moored, the installation vessel can recover the buoy back onto the deck, disconnect the buoy from the mooring line assembly, and approach the floating platform. Using a crane on the floating platform, a pre-installed short top section of the mooring line assembly 115 can be handed over to the installation vessel.

When both the mooring line bottom section running to the anchor and the mooring line top section from the floating platform are on the deck of the installation vessel, both ends can be connected using an Η-Link or similar joining method. The mooring line can then be lowered subsea using a work wire 116 from the installation vessel - see Figure 15.

With the mooring line assembly hanging relatively slack, the work wire from the installation can be disconnected from the mooring line assembly using a Remotely Operated Vehicle (ROV). When the work wire is disconnected it is recovered to the vessel, the mooring line assembly is now fully connected and appears as in Figure 16.

A possible variation on this installation method would be to remove the preinstalled section of mooring line attached to the floating platform that is used to hand over to the installation vessel. GB 2 512 312 A (also by the present Applicant), shows a device for the connection under tension of a mooring line to a floating structure - the connection being made directly at the interface between hull and mooring line. (See Figure 17).

The details of this connection method are disclosed in further detail in GB 2 512 312 A. This connection method could easily be incorporated into the overall mooring installation procedure outlined herein. The mooring line would be deployed by the installation vessel with the male connector from GB 2 512 312A. The pull-in rope 115 (see Figure 17) would be connected to the floating platform crane which would perform the pull-in.

With the mooring line fully connected, the installation vessel can now lower a work wire to be connected to the rope sling 113 that is attached to the end of the chain that passes through the tensioner and chain stopper 110.

With the work wire attached to the chain that passes through the tensioner and chain stopper, the vessel can pull upwards on the wire to increase tension in the mooring line. The chain stopper engages should the work wire be slackened locking in the tension generating in the mooring line by previously pulling upwards.

During tensioning the tension generated in the section of mooring line below the tensioner will be greater than the tension applied from the surface vessel. The extent to which the load from the vessel is magnified will depend upon the wrap angle of the chain around the 5 pocket wheel (see Figure 1(c).

Once the required tension has been reached the work wire is lowered until the chain stopper automatically engages with the chain 110 and the work wire goes slack. The mooring chain that has been pulled through the tensioner will be slack in service. It can be locked in position using the pin 112 provided. Excess slack chain could be removed using an ROV operated saw. With the slack chain secured by the pin, an

ROV can disconnect the work wire from the rope sling 113. This completes the installation and tensioning of the mooring line.

It should be understood that the embodiments described herein are merely exemplary and that various modifications may be made thereto without departing from the scope of the invention.

It will be appreciated that in other examples, the line may be or include an offshore mooring line, underwater mooring line or subsea mooring line or the like.

08 17

Claims

1. A method of installing a mooring line or mooring line assembly comprising: providing first and second mooring lines;

5 providing a retention, clamping and/or tensioning device for retaining, clamping and/or tensioning the first and second lines together so as to provide a mooring line assembly; and connecting a distal end of one of the mooring lines to an anchor.

10

2. The method according to claim 1, wherein connecting one end of the mooring line to a subsea anchor is preceded by lowering the mooring line assembly within a body of water.

3. The method of claim 1 or 2, wherein the distal end of the one of the mooring

15 lines comprises a first connector portion, which is a male connector portion.

4. The method of any of claims 1 to 3, wherein the anchor comprises a second connector portion, which is a female connector portion, and which mates with the first connector portion.

5. The method of claim 4, wherein the female connector portion is provided on one end of a yet further line, another end of the yet further line being connected to the anchor.

25

6. The method of claim 4 or 5, wherein a holder is provided on the anchor to releasably hold the female connector portion.

7. The method of any of claims 4 to 6, wherein the female connector is released from the holder if and/or when tension is applied to the yet further line.

8. The method of any of claims 1 to 7, wherein the other mooring line passes or is threaded through the retaining, clamping and/or tensioning device.

01 08 17

9. A method of mooring, such as offshore mooring, such as mooring of a buoyant structure, the method comprising:

installing a mooring line assembly according to claim 1;

10. The method of claim 9 wherein the method also comprises the step of adjusting tension on the mooring line(s).

11. A method of installing a mooring line assembly comprising:

10 providing a first mooring line;

connecting the retention, clamping and/or tensioning device to an anchor.

15

12. The method of claim 11, wherein the retention, clamping and/or tensioning device comprises a first connector portion, which is a male connector portion.

13. The method of claim 11 or 12, wherein the anchor comprises a second connector portion, which is a female connector portion, which mates with the first

20 connector portion.

14. The method of claim 13, wherein the female connector portion is provided on one end of a yet further line, another end of the yet further line being connected to the anchor.

15. The method of claim 13 or 14, wherein a holder is provided on the anchor to releasably hold the female connector portion

16. The method of claim 13 to 15, wherein the female connector is released from 30 the holder if and/or when tension is applied to the yet further line.

17. The method of any of claims 13 to 16, wherein the mooring line passes or is threaded through the retaining, clamping and/or tensioning device.

18.

5 19.

20.

A method of mooring, the method comprising:

installing a mooring line assembly according to any of claims 11 to 17; connecting a distal end of the first mooring line to a/the structure.

A mooring line assembly according to any of claims 1 to 17.

A mooring system comprising a mooring line assembly according to claim 19.

01 08 17

Intellectual

Property

Office

Application No: GB1617187.8 Examiner: Chris Bennett