MOORING/TENSIONING APPARATUS

Abstract

There is disclosed an apparatus for mooring a structure and/or tensioning a mooring line. The apparatus comprises: a guide portion for guiding a portion of a first mooring line, and a lock arrangement, wherein the apparatus provides a mooring line path, the lock arrangement being provided on an opposite side of the mooring line path from the guide portion, at least when the lock arrangement is in an unlocked configuration. When in a locked configuration at least a portion of the lock arrangement is provided in the mooring path.

Claims

1. An apparatus or device for mooring a structure and/or tensioning a mooring line, the apparatus or device comprising: a body and a guide portion for guiding at least a portion of a first mooring line along a mooring line path; wherein the body comprises an open channel for guiding and/or seating the first mooring line.

2. A (mooring) system for tensioning a first mooring line, the system comprising at least one device or apparatus according to claim 1, the first mooring line, and a second mooring line.

3. A method for tensioning a mooring line, the method comprising: providing a system for tensioning a mooring line according to claim 2, the method further comprising: applying a pulling force to a/the first portion of a/the first mooring line in a direction away from the apparatus or device.

4. The apparatus or device of claim 1, wherein: the open channel comprises a partial-cruciform or half-cruciform shaped surface; the open channel comprises a first U-shaped or D-shaped surface, with a second, smaller D-shaped or U-shaped surface disposed at a mid-point of the first U-shaped or D-shaped surface; the open channel comprises a first cupped or cup-shaped surface, with a second, smaller cup-shaped or cupped, D-shaped or U-shaped surface disposed at a mid-point of the first cupped or cup-shaped surface; the open channel comprises a substantially recessed or concave first portion, with a second, recessed portion disposed at a mid-point of the first portion; the open channel comprises a first trough, with a second smaller trough disposed at a mid-point of a deepest portion of the first trough; and/or a cross-section of the open channel is substantially T-shaped.

5. An apparatus or device as claimed in claim 4, wherein: the partial-cruciform or half-cruciform shaped surface is shaped and sized to conform to at least a portion of the first mooring line, e.g. shaped and sized to conform to a mooring line or chain; and/or the partial-cruciform or half-cruciform shaped surface is configured to seat the mooring line.

6. An apparatus or device as claimed in claim 1, wherein: a/the surface of the open channel, or the partial-cruciform or half-cruciform shaped surface, is configured to inhibit pivoting of the mooring line relative to the body in a first direction perpendicular to the mooring line path and away from the guide portion; the open channel is provided to allow pivoting of the mooring line relative to the body between a/the surface of the open channel and the guide portion; and/or the open channel comprises sidewalls configured to inhibit pivoting of the mooring line in a third direction, the third direction being perpendicular to the mooring line path and the first direction.

7. An apparatus or device as claimed in claim 1, wherein: the open channel is located or disposed at or adjacent a periphery of the body; the open channel is located or disposed at an entry and/or exit point of or from the apparatus; the entry and/or exit point is an entry and/or exit point of the mooring line, e.g. an entry and/or exit point of the mooring line relative to the body; and the open channel is provided between the guide portion and a structure to be moored, in use.

8. An apparatus or device as claimed in claim 1, wherein: the body comprises a connection portion for connecting the apparatus or device to a second mooring line, the guide portion optionally being disposed between the connection portion and the open channel, wherein optionally the connection portion is disposed on the body such that, during tensioning of the first and/or second mooring lines, the first mooring line moves or pivots relative to the body in response to a tilting or rotation of the body, optionally the movement or pivoting of the first mooring line relative to the body being movement or pivoting between a/the surface of the open channel and the guide portion; the connection portion may be disposed on the body such that, during tensioning of the mooring lines, the body tends to tilt or rotate to align a line between a centre of the guide portion and the connection portion with the second mooring line; and/or the connection portion comprises a pad-eye, shackle or clevis.

9. An apparatus or device as claimed in claim 1, wherein, in use, the first mooring line is free to move or pivot in the open channel relative to the body.

10. An apparatus or device as claimed in claim 1, where the apparatus comprises a lock arrangement or means.

11. An apparatus or device as claimed in claim 1, wherein the lock arrangement or means is adapted to engage the first mooring line to inhibit movement of the mooring line relative to the body in a direction along the mooring line path and allow movement of the mooring line relative to the body in an opposite direction along the mooring line path; the lock arrangement or means is provided on an opposite side of the mooring line path from the guide portion; the lock arrangement or means is adapted to be provided between the guide portion and a structure to be moored, in use; the lock arrangement is provided between the guide portion and a structure to be moored along a path of a mooring line, for example, along the mooring line path; the lock arrangement is provided proximal or adjacent the guide portion; the lock arrangement or means is configurable to straddle the guide portion; the lock arrangement comprises a yoke, the yoke optionally being configured to straddle the guide portion, and/or the yoke being configured to straddle the first mooring line, e.g. the first mooring line; the lock arrangement comprises a finger, the finger optionally being configured to interfere with, such as abut, the guide portion, and/or the finger being configured to interfere with, such as abut, the mooring line, e.g. the first mooring line; and/or the lock arrangement or means is configurable to straddle the first mooring line.

12. An apparatus or device as claimed in claim 1, wherein the lock arrangement or means comprises a lock member, and wherein optionally: in a first, unlocked, disposition the lock member is distal or non-coincident with the mooring line path, and/or in a second, locked, disposition at least part of the lock member is coincident with the mooring line path, e.g., in said second disposition, an end of the lock member may engage with the (first) mooring line, e.g. with a link of a mooring line comprising a mooring chain; the lock member is connected to or provided on the body, e.g. pivotably attached to the body; and/or an/the end of the lock member is closer to a structure to be moored when in the second locked disposition than when in the first, unlocked, disposition.

13. An apparatus or device as claimed in claim 10, wherein: the lock arrangement or means comprises a pivotable member or clacker, and/or the lock member comprises a pivotable member or clacker; and/or the lock arrangement or means comprises a counterweight, e.g. removable counterweight, for biasing the lock arrangement or means or the pivotable member or clacker towards engagement with the first mooring line, and optionally a point of rotation of the pivotable member or clacker is provided on the opposite side of the mooring line path from the guide portion; the lock arrangement or means is adapted to hold or seat the mooring line between the guide portion and the pivotable member or clacker; and/or in use, at least a portion of the first mooring line is disposed between the lock arrangement or means and the guide portion.

14. An apparatus or device as claimed in claim 1, wherein: the mooring line path comprises a curved path; the mooring line path comprises an included or interior angle α and an excluded or exterior angle β; wherein optionally the guide portion is provided on or within the interior angle α of the mooring path; a/the lock arrangement or means is provided, e.g. in a first (unlocked) disposition, on or within the exterior angle β of the mooring line path.

15. An apparatus or device as claimed in claim 1, wherein: the guide portion is movably, e.g. rotatably, mounted on the body; the guide portion comprises a chain wheel, a sprocket or a pocket wheel; the guide portion is substantially circular, such as a mooring line wheel or a chain wheel which is rotatable relative to the body, such as around a central axis of the guide portion; the guide portion is a sprag wheel, a sheave, a toothed wheel, such as a cogwheel.

16. The apparatus or device as claimed in claim 1, wherein: the apparatus or device is suitable for offshore and/or subsea operations and submerged, in use; by the apparatus a (first) mooring line can be tensioned; the apparatus is a “mid-line tensioner” and/or “inline tensioner”.

17. The apparatus or device as claimed in claim 1, wherein: a/the lock arrangement comprises a mooring line lock, e.g. capable of locking or retaining the first mooring line; in use, at least a portion of the first mooring line is disposed, locked and/or secured by the lock arrangement; a/the lock is adapted to secure and/or lock the first mooring line between the lock arrangement and an outer peripheral/circumferential portion of body; the guide portion is rotatably connected to the body, e.g. on or around an axis; and/or a/the lock arrangement is hingedly or pivotably connected to the body.

18. The apparatus or device as claimed in claim 1, wherein: at least a portion of at least one or both of the mooring lines is a chain, wire, or rope; at least a portion of the first mooring line is a first chain; at least a portion of a/the second mooring line is a second chain.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0203] Embodiments of the present invention will now be described by way of example only, and with reference to the accompanying drawings, which are:

[0204] FIG. 1 a side view of a first mooring apparatus according to the prior art;

[0205] FIG. 2 a side view of a second mooring apparatus according to the prior art;

[0206] FIG. 3 a side view of a third mooring apparatus according to the prior art;

[0207] FIG. 4 a side view of a mooring apparatus or device according to an embodiment of the present invention;

[0208] FIG. 5 a sectional side view of the mooring apparatus of FIG. 4 with a first mooring line in situ;

[0209] FIG. 6 a perspective view from above and to one side of the mooring apparatus of FIG. 4;

[0210] FIG. 7 a side view of the mooring apparatus of FIG. 4 with first and second mooring lines in situ;

[0211] FIG. 8 a sectional side view of the mooring apparatus of FIG. 4 with first and second mooring lines in situ;

[0212] FIG. 9 a top view of the mooring apparatus of FIG. 4 with first and second mooring line in situ;

[0213] FIG. 10 an end view of the mooring apparatus of FIG. 4 with a first mooring line in situ;

[0214] FIG. 11 a sectional partial side view to an enlarged scale of the mooring apparatus of FIG. 4;

[0215] FIG. 12 a partial side view to an enlarged scale of the mooring apparatus of FIG. 4;

[0216] FIG. 13 a partial view from one side and one end and to an enlarged scale of the mooring apparatus of FIG. 4; and

[0217] FIG. 14 a diagrammatic representation of a mooring system comprising a mooring apparatus of FIG. 4;

[0218] FIG. 15 a perspective view of a mooring apparatus or device according to an embodiment of the present invention;

[0219] FIG. 16 a cross-sectional side view of the mooring apparatus or device of FIG. 15;

[0220] FIG. 17 a front view of a body of the mooring apparatus or device of FIG. 15;

[0221] FIG. 18 a perspective view of a lock arrangement of the mooring apparatus or device of FIG. 15;

[0222] FIG. 19 a photograph of a mooring apparatus or device in use;

[0223] FIGS. 20(a) to (c) a series of photographs of a mooring apparatus or device according to an embodiment of the present invention in use;

[0224] FIGS. 21(a) to (b) a further series of photographs of a mooring apparatus or device according to an embodiment of the present invention in use;

[0225] FIGS. 22 to 25 a series of sectional side views of a mooring apparatus according to an embodiment of the present invention;

[0226] FIG. 26 a sectional side view of a mooring apparatus according to an embodiment of the present invention;

[0227] FIGS. 27(a) and (b) detailed sectional side view of the mooring apparatus of FIGS. 22 and 25 respectively;

[0228] FIGS. 28(a) to (d) perspective views of first to fourth mooring apparatus according to embodiments of the present invention;

[0229] FIGS. 29(a) and (b) first and second combination of guide portions and lock members for use in embodiments of the present invention;

[0230] FIGS. 30(a) to (d) a series of schematic side views of a mooring apparatus corresponding to a number of the previously disclosed embodiments of the present invention; and

[0231] FIGS. 31(a) to (d) a series of schematic side views of a mooring apparatus corresponding to a number of the previously disclosed embodiments of the present invention.

DETAILED DESCRIPTION OF DRAWINGS

[0232] Referring initially to FIG. 1, there is shown a chain tensioner generally designated 17, according to the prior art as disclosed in US 2014/0216323 A1 (SINGLE BUOY MOORINGS). As shown in FIG. 1, a chain tensioner 17 is fixedly attached with a connection side 18 to an upper end of chain section 15 via a chain link 14 and connector member, such as a bow shackle 22. Instead of chain section 15, a wire rope or other line section is utilised to connect to side 18 of the chain tensioner device 17 using a suitable connector member. During connection of the upper end of chain section 15 to the chain tensioner device 17, the chain section 15 remains clamped on deck of the vessel. A working chain 20 having a length of for instance 200 metres, is on deck of a vessel movably passed through the chain tensioner 17 by feeding tensioning chain section 28 that is formed by the lower part of the working chain 20 via an entry side 19 of the chain tensioner 17 through a chain stopper 25 and along a sheave 23. The chain stopper 25 functions as a ratchet and only allows passage of the working chain 20 through the tensioner housing 27 in the direction of the shorter tensioning chain part 28 that becomes longer upon pulling it in the direction indicated as T. The tensioning chain part 28 of the tensioning chain 20 is guided via the rotatable sheave 23 out through an opening 26 in the housing 27 of the chain tensioner 17. A pulling eye 24 of relatively large diameter is attached to tensioner chain part 28 for handling by a remote operated vehicle (ROV).

[0233] Referring now to FIGS. 2 and 3, there is shown an apparatus for mooring a structure, the apparatus comprising a mooring tensioner, generally designated 10 according to the prior art as disclosed in WO 2018/025018 A1 (FLINTSTONE TECHNOLOGY LIMITED).

[0234] Referring now to FIGS. 4 to 13, there is shown a (mooring and/or tensioning) apparatus or device, generally designated 100, according to an embodiment of the present invention. Hereinafter the apparatus or device 100 will be referred to as apparatus 100.

[0235] The apparatus 100 comprises:

[0236] a guide portion (or sheave) 105 for guiding a portion of a first (working) mooring line 110, and

[0237] a lock arrangement or means 115, wherein the apparatus 100 provides a mooring line path 120, the lock arrangement 115 is provided on an opposite side of the mooring line path 120 from the guide portion 105, and the lock arrangement 115 is providable between the guide portion 105 and a structure 200 to be moored, in use, at least in a locked disposition, e.g. along the mooring line path.

[0238] The lock arrangement 115 is providable between the guide portion 105 and a structure 200 to be moored along a path of a mooring line, i.e. along the mooring line path 120.

[0239] The lock arrangement 115 is provided proximal or adjacent the guide portion 105.

[0240] The apparatus 100 provides for a lock arrangement 115 which is significantly closer to the guide portion 105 than in the prior art. This can result in one or more advantages, e.g. reduced length, reduced weight, and/or reduce the cost of the apparatus 100.

[0241] The apparatus 100 also provides advantage over one or more prior art apparatus in that, in use, the mooring line 110 around the guide portion 105 is not under tension when the structure 200 is moored, since tension is taken by the lock arrangement 115.

[0242] The mooring line path 120 comprises a curved path. The mooring line path 120 comprises an included or interior angle α, and an excluded or exterior angle β.

[0243] The guide portion 105 is provided on or within the interior angle α of the mooring line path. The lock arrangement 115 is provided on or within the exterior angle β of the mooring line path 120, i.e. on an opposite side of the mooring line path from the guide portion 115, at least in an unlocked disposition.

[0244] The apparatus 100 comprises a body 125. The guide portion 105 is movably, i.e. rotatably, mounted on the body 125.

[0245] The lock arrangement 115 comprises a lock member 130 having a lock face or side 131. In a first (unlocked) disposition, the lock member 130 is distal or non-coincident with the mooring line path 120. In a second (locked) disposition, at least part of the lock member 130 is coincident with the mooring line path 120. (Further details with regard to the operation of the apparatus 100 can be understood from FIGS. 30(a) to (d) and FIGS. 31(a) to (d)). For example, in said second disposition, an end 135 of the lock member 130 engages with the mooring line 110, e.g. with a link 140 of a mooring line 110 comprising a mooring chain. The lock member 130 can be biased to the second disposition by biasing means (not shown).

[0246] The lock member 130 is connected to or provided on the body 125, i.e. pivotably attached to the body 125. A pivot 131 of the lock member 130 is on an opposite side of the mooring line path 120 than the guide portion 105.

[0247] The end 135 of the lock member 130 is closer to a structure 200 to be moored when in the second, locked, disposition than when in the first, unlocked, disposition.

[0248] The body 125 comprises an arrangement 145 for connecting or coupling the apparatus 100 to a second mooring line 150.

[0249] The guide portion 105 comprises a circular member or wheel. The guide portion 105 comprises a plurality of circumferentially disposed teeth 155, which may, in use, co-act with a/the end 135 of the lock member 130, for example, so as to lock a/the mooring line 110 relative to the apparatus 100 when the lock member 130 is in the second (locked) disposition. The lock member 130, therefore, acts as a pawl, which together with the toothed guide portion 105 can act as a ratchet type mechanism.

[0250] The lock arrangement 115 is conveniently referred to as a “chain stopper”.

[0251] In this embodiment the guide portion 105 comprises first and second sides, which are circular and comprise respective first and second teeth 155a, 155b, pairs of which are circumferentially aligned, i.e. face one another.

[0252] At least a portion of the mooring line path 120 is provided between the first and second sides of the guide portion 105.

[0253] The body 115 comprises a guide arrangement 160 for guiding a portion of a mooring line 110, for example, into or out of the apparatus 100. In this embodiment the guide arrangement 160 comprise a pair of opposing guide members.

[0254] The lock arrangement 115 is provided between the guide portion 105 and the guide arrangement 160.

[0255] In use, when tension is applied to an end of a mooring line 110 distal a structure 200 or on an opposite side of the apparatus 100 from a structure 200, the lock member 130 will tend towards or be disposed in the first (unlocked) disposition. This allows the mooring line 110 to be tensioned.

[0256] In use, when tension is removed from an end of a mooring line 100 distal a structure 200 or an opposite side of the apparatus 100 from a structure 200, the lock member 130 will tend towards or be disposed in the second (locked) disposition. This allows the mooring line 110 to be locked (relative to the apparatus 100).

[0257] By this apparatus 100 a (first) mooring line 110 may be tensioned. The apparatus 100 comprises and/or can be referred to as a “mid-line tensioner”.

[0258] The lock arrangement 115 comprises a mooring line lock, i.e. capable of locking or retaining the first mooring line 110.

[0259] In use, at least a portion of the first mooring line 110 is disposed, locked and/or secured by the lock arrangement 115 and the guide portion 105.

[0260] The at least a portion of the first mooring line 110 comprises a locked link 111. A link adjacent the locked link 111 in a direction away from the guide portion 105 can be referred to as a first loaded link 112. The lock member 130 has a lock face 131.

[0261] The lock arrangement 115 is adapted to secure and/or lock the first mooring line 110 between the lock arrangement 115 and an outer peripheral portion of body 125.

[0262] The guide portion 105 is rotatably connected to the body 125, e.g. on or around an axis.

[0263] The lock arrangement 115 and/or lock member 130 is hingedly or pivotably connected to the body 125, beneficially on a side of the mooring line path opposite the guide portion 105.

[0264] At least a portion of at least one or both of the mooring lines 110, 150 can be a chain, wire, rope, or the like. At least a portion of the first mooring line 110 can be a first chain. At least a portion of the second line mooring150 can be a second chain.

[0265] The guide portion 105 can be a sheave or wheel, and/or can be substantially circular, such as a mooring line wheel or a chain wheel which can be rotatable relative to the body 125, such as around a central axis A of the guide portion 105. The guide portion 105 can be a sprag wheel. The guide portion 105 can be a sheave. The guide portion 105 can be a toothed wheel, such as a cogwheel, or the like.

[0266] The present invention provides an (mooring) apparatus or device 100 for mooring a structure 200, the apparatus or device 100 comprising:

[0267] a body 125;

[0268] a guide portion 105 for guiding a portion of a first mooring line 110;

[0269] a lock arrangement or means 115, wherein

[0270] the guide portion 105 is provided on and/or within a first side or end of the body 125, and the lock arrangement or means 115 is provided on and/or within a second side or end of the body 125, which second side or end at least partly opposes the first side or end.

[0271] The apparatus 100 provides mooring line path 120. The lock arrangement 125 is provided on an opposite side of the mooring line path 120 from the guide portion 105. The lock arrangement 115 is provided between the guide portion 105 and a structure 200 to be moored, in use.

[0272] Referring to FIG. 14, the present invention provides a system 205 for tensioning a (first) mooring line 110, the system 205 comprises at least one mooring apparatus 110 as hereinbefore described.

[0273] The system 205 comprises a first mooring line 110. The system 205 comprises a second mooring line 150.

[0274] The system 205 moors at least one structure 205, such as a floating structure, an offshore structure, a floating platform or the like.

[0275] A portion of the first mooring line 110 is threaded or threadable through the apparatus 200.

[0276] A first portion or end 116 of the first mooring line 110 is configured to be connected or connectable to the structure 200.

[0277] The system 205 can comprise a buoy (not shown). The system 205 comprises a floating vessel 210. The system 205 comprises a winch and/or a pulley 215. The winch and/or pulley 215 may be located on or in the floating vessel 210. The buoy can be a submersible buoy, a semi-submersible buoy, a submerged turret production buoy, a submerged turret loading buoy or the like.

[0278] A second portion or end 117 of the first mooring line 110 is configured to be connected to the buoy and/or the floating vessel and/or the winch and/or the pulley 215. The winch and/or pulley 215 can be adapted to set, adjust or increase a tension in the first mooring line 110.

[0279] A first portion or end 118 of the second mooring line 115 can be connected to at least a portion of the apparatus 110. The first portion or end 116 of the second mooring line 150 can be connected to the body 125. The first portion of the second mooring line 150 can be releasably connected to the body 125.

[0280] The system 205 comprises an anchor 220. The anchor 220 comprises an anchoring point. The anchor 220 can be a pile, such as a suction pile or the like. The anchor 220 can be a subsea formation. The anchor 220 can be adapted for use on a seabed 225.

[0281] A second portion 119 of the second mooring line 150 can be connected to the anchor 220 or to the anchoring point.

[0282] The present invention provides a method of tensioning a (first) mooring line 110, wherein the method comprises:

[0283] providing a system 205 for tensioning a (first) mooring line 110 as hereinbefore described, the method (further) comprising:

[0284] applying a pulling force to a portion 117 of a first mooring line 110 in a direction away from the apparatus 100.

[0285] The pulling force can cause the apparatus 100 to pull at least one other portion of the first mooring line 110 towards a second mooring line 150.

[0286] The pulling force can cause the apparatus 100 to pull at least one other portion of the first mooring line 110 towards the apparatus 100.

[0287] When an appropriate or desired tension has been applied to the mooring line 110, the lock arrangement 115 can be disposed in the locked position.

[0288] When an appropriate or desired tension has been applied to the mooring line 110, the portion or end 117 of the first mooring line 110 can be attached to a buoy, or the like.

[0289] When an appropriate tension has been applied to the mooring line 110, at least a portion of the first portion of the first mooring line 110 can be cut away and/or removed and/or secured to the apparatus 100 and/or secured to the first and/or second mooring lines 110, 150.

[0290] The present invention provides a method for releasing tension in a mooring line, the method comprising:

[0291] providing a system for tensioning a mooring line as hereinbefore described, the method (further) comprising:

[0292] applying a pulling force to a/the first portion 112 of a/the first mooring line 110 in a direction away from the apparatus 100;

[0293] releasing the lock 115 from a locked disposition and/or retaining the lock 115 arrangement in a unlocked disposition; and

[0294] reducing and/or removing the pulling force.

[0295] The step of retaining the lock arrangement 115 in the unlocked disposition can require removal and/or repositioning and/or insertion of at least one locking pin (not shown).

[0296] Referring now to FIGS. 15 and 16, there is shown a mooring and/or tensioning apparatus or device, generally designated 300, according to an embodiment of the present invention. Hereinafter the apparatus or device 300 will be referred to as apparatus 300.

[0297] The apparatus 300 comprises a body 325 and a guide portion 305 for guiding at least a portion of a first mooring line 310 along a mooring line path 320. The body 325 comprises an open channel 365 for guiding and seating the first mooring line 310.

[0298] The open channel 365 comprises a partial-cruciform or half-cruciform shaped surface, as can be seen more clearly in FIG. 17, which shows a front view of the body 325 of the mooring apparatus 300 of FIGS. 15 and 16. That is, a cross-section of the open channel 365 is substantially T-shaped, as described in more detail below.

[0299] The open channel 365 comprises a first U-shaped surface 370, with a second, smaller U-shaped surface 375 disposed at a mid-point of the first U-shaped shaped surface 370. In other embodiments, the open channel 365 comprises a first D-shaped surface, with a second, smaller D-shaped surface disposed at a mid-point of the first D-shaped shaped surface. In yet further embodiments, the open channel 365 corresponds to a first trough 370, with a second smaller trough 375 disposed at a mid-point of the deepest portion of first trough 370.

[0300] The surface 370, 375 of the open channel is shaped and sized to conform to at least a portion of the first mooring line 310.

[0301] The surface 370, 375 of the open channel 365 is configured to seat the mooring line 310.

[0302] The surface 370, 375 of the open channel 365 is configured to inhibit pivoting of the mooring line 310 relative to the body 325 in a first direction 380 perpendicular to the mooring line path 320 and away from the guide portion 305.

[0303] The open channel 365 is provided to allow pivoting of the mooring line 310 relative to the body 325 between a/the surface of the open channel 365 and the guide portion 305.

[0304] The open channel 365 may comprise sidewalls 390, 395 configured to inhibit pivoting of the mooring line 310 in a third direction 350, the third direction being perpendicular to the mooring line path 320 and the first direction 380.

[0305] The body 325 comprises a connection portion 345 for connecting or coupling the apparatus 300 to a second mooring line (not shown).

[0306] The connection portion 345 may comprise a pad-eye, shackle or clevis. In the example embodiment of FIGS. 15, 16 and 17, the connection portion 345 is a padeye.

[0307] The guide portion 305 is disposed between the connection portion 345 and the open channel 365.

[0308] The connection portion 345 is disposed on the body 325 such that, during tensioning of the first 310 and second mooring lines, the first mooring line 310 moves or pivots relative to the body 325 in response to a tilting or rotation of the body 325. The movement or pivoting of the first mooring line 310 relative to the body 325 is movement or pivoting between the surface 370, 375 of the open channel 365 and the guide portion 305.

[0309] In use, the first mooring line 310 is free to move or pivot in the open channel 365, relative to the body 325.

[0310] The connection portion 345 is disposed on the body 325 such that, during tensioning of the mooring lines, the body 325 tends to tilt or rotate to align a line 360 between a centre of the guide portion and the connection portion with the second mooring line.

[0311] The apparatus 300 further comprises a lock arrangement or means 315, wherein the lock arrangement 315 is provided on an opposite side of the mooring line path 320 from the guide portion 305, and the lock arrangement 315 is provided between the guide portion 305 and a structure to be moored, in use.

[0312] The lock arrangement 315 is provided between the guide portion 305 and a structure (not shown) to be moored along a path of a mooring line, i.e. along the mooring line path 320.

[0313] The lock arrangement 315 is adapted to engage the first mooring line 310 to inhibit movement of the first mooring line 310 relative to the body 325 in a direction along the mooring line path 320 and allow movement of the first mooring line 310 relative to the body 325 in an opposite direction along the mooring line path 320.

[0314] The lock arrangement 315 is provided, e.g. at least in an unlocked disposition, on an opposite side of the mooring line path 320 from the guide portion 305′.

[0315] The lock arrangement 315 is adapted to be provided, e.g. at least in a locked disposition, between the guide portion 305 and a structure to be moored, in use.

[0316] In the example embodiment of FIGS. 15, 16 and 17, the lock arrangement 315 is configurable to straddle the guide portion 305. In the example embodiment of FIGS. 15, 16 and 17, the lock arrangement 315 is configurable to straddle the first mooring line 310.

[0317] The lock arrangement 315 comprises a pivotable member or clacker 405, as shown in FIG. 18.

[0318] The lock arrangement 315 comprises a counterweight 410 (which can be removable) for biasing the pivotable member or clacker 405 towards engagement with the first mooring line 310.

[0319] The lock arrangement 315 is adapted to hold or seat the mooring line 310 between the guide portion 305 and the pivotable member or clacker 405.

[0320] In use, at least a portion of the first mooring line 310 is disposed between the lock arrangement 315 and the guide portion 305.

[0321] The lock arrangement 315 is provided proximal or adjacent the guide portion 305.

[0322] The apparatus 300 provides for a lock arrangement 315 which is significantly closer to the guide portion 305 than in the prior art. This can result in one or more advantages, e.g. reduced length, reduced weight, and/or reduce the cost of the apparatus 300.

[0323] The apparatus 300 also provides advantage over one or more prior art apparatus in that, in use, the mooring line 310 around the guide portion 305 is not under tension when the structure (not shown) is moored, since tension is taken by the lock arrangement 315.

[0324] The mooring line path 320 comprises a curved path. The mooring line path 320 comprises an included or interior angle θ and an excluded or exterior angle ϕ.

[0325] The guide portion 305 is provided on or within the interior angle θ of the mooring line path. The lock arrangement or means 315 is provided, at least in an unlocked disposition, on or within the exterior angle ϕ of the mooring line path 320, i.e. on an opposite side of the mooring line path from the guide portion 315.

[0326] The apparatus 300 comprises a body 325. The guide portion 305 is movably, e.g. rotatably, mounted on the body 325.

[0327] The lock arrangement 315 comprises a lock member 330, e.g. pivotable member or clacker 405. In a first (unlocked) disposition, the lock member 330 is distal or non-coincident with the mooring line path 320. In a second (locked) disposition, at least part of the lock member 330 is coincident with the mooring line path 320. For example, in said second disposition, an end 335 of the lock member 330 engages with the mooring line 310, e.g. with a link 340 of a mooring line 310 comprising a mooring chain. The lock member 330 can be biased to the second disposition by biasing means (not shown).

[0328] The lock member 330 is connected to or provided on the body 325, e.g. pivotably attached to the body 325.

[0329] The end 335 of the lock member 330 is closer to a structure (not shown) to be moored when in the second, locked, disposition than when in the first, unlocked, disposition.

[0330] The apparatus 300 comprises a mid-line tensioner.

[0331] The guide portion 305 comprises a circular member or wheel. The guide portion 305 comprises a plurality of circumferentially disposed teeth 355, which may, in use, co-act with a/the end 335 of the lock member 330, for example, so as to lock a/the mooring line 310 relative to the apparatus 300 when the lock member 330 is in the second locked disposition. The lock member 330, therefore, acts as a pawl, which together with the toothed guide portion 305 can act as a ratchet type mechanism.

[0332] The lock arrangement 315 is conveniently referred to as a “chain stopper”.

[0333] The lock arrangement 315 is provided between the guide portion 305 and the open channel 365.

[0334] In use, when tension is applied to an end of a mooring line 310 distal a structure (not shown) or on an opposite side of the apparatus 300 from a structure, the lock member 330 will tend towards or be disposed in the second (locked) disposition. This allows the mooring line 310 to be tensioned.

[0335] In use, when tension is removed from an end of a mooring line 300 distal a structure (not shown) or an opposite side of the apparatus 300 from a structure, the lock member 330 will tend towards or be disposed in the first (unlocked) disposition.

[0336] By this apparatus 300 a (first) mooring line 310 may be tensioned. The apparatus 300 can be referred to as a “mid-line tensioner”.

[0337] The lock arrangement 315 comprises a mooring line lock, i.e. capable of locking or retaining the first mooring line 310.

[0338] In use, at least a portion of the first mooring line 310 is disposed, locked and/or secured by the lock arrangement 315 and the guide portion 305.

[0339] The guide portion 305 is rotatably connected to the body 325, e.g. on or around an axis.

[0340] The lock arrangement 315 and/or lock member 330 is hingedly or pivotably connected to the body 325.

[0341] At least a portion of the mooring lines 310 can be a chain, wire, rope, or the like.

[0342] The guide portion 305 can be a wheel and/or can be substantially circular, such as a mooring line wheel or a chain wheel which is rotatable relative to the body 325, such as around a central axis of the guide portion 305. The guide portion 305 can be a sprag wheel. The guide portion 305 can be a sheave. The guide portion 305 can be a toothed wheel, such as a cogwheel, sprocket, or the like.

[0343] The apparatus 300 may be suitable for offshore and/or subsea operations and may be submerged in use.

[0344] FIG. 19 shows a photograph of an apparatus, generally denoted 400, in use. The apparatus 400 does not comprise an open channel for guiding and/or seating a first mooring line 410. The first mooring line 410 is being pulled along a path indicated by arrow 420, thus tensioning the first mooring line 410 and a second mooring line 430. It can be seen the first mooring line 410, which is a mooring chain, interferes with an upper portion of a closed channel 440. That is, during tensioning of the mooring lines 410, 430, the apparatus 100 may obstruct movement of the first mooring line 410 relative to the apparatus 400, due to an angle at which the first mooring line 410 enters the closed channel 440 of the apparatus 400. Such interference may result in the first mooring line 400 moving in a jolting manner relative to the apparatus 400, and may result in damage to the first mooring line 410 and/or the apparatus 400. Furthermore, such behaviour may potentially lead to a jamming of the first mooring line 410 in or around the apparatus 400.

[0345] FIGS. 20(a) to (c) shows a series of photographs of an apparatus 500 according to an embodiment of the present invention. In FIG. 20(a), a first mooring line 510 and a second mooring line 530 are under a low tension, e.g. a substantial tensioning force in a direction indicated by arrow 520 has not yet been applied to the first mooring line 510. The apparatus 500 does comprises an open channel 540 for guiding and/or seating a first mooring line 510.

[0346] In FIG. 20(b), the first mooring line 510 is being pulled along a path indicated by arrow 520, thus tensioning the first mooring line 510 and a second mooring line 530. In contrast to FIG. 19, it can be seen that the first mooring line 510, which is a mooring chain, does not interferes with the channel 540. That is, during tensioning of the mooring lines 510, 530, due to the open channel 540, the apparatus 500 does not obstruct movement of the first mooring line 510 towards a guide portion 560. FIG. 20c shows the first mooring line 510 and the second mooring line 530 further tensioned relative to FIG. 20b. It can be seen that during tensioning of the mooring lines 510, 530, a body 570 of the apparatus 500 tends to tilt or rotate to align a line 580 between a centre of the guide portion and a connection portion 590 with the second mooring line 530.

[0347] FIGS. 21(a) and 21(b) show a further series of photographs of the mooring apparatus 500 in use. In FIGS. 21(a) and 21(b), the first mooring line 510 is being pulled along a path indicated by arrow 525, thus tensioning the first mooring line 510 and the second mooring line 530. In contrast to FIG. 20b, it can be seen that an angle between arrow 525 and a portion of the first mooring line 515 is substantially lower than an angle between arrow 525 and a portion of the first mooring line 515 in FIG. 20(b). That is, a wrap angle around guide portion 560 is larger in FIGS. 21(a) and 21(b) than in FIG. 20(b). As a result, the first mooring line 510 is lifted further into the open channel.

[0348] Referring to FIGS. 22 to 25 there is shown an apparatus 600 according to an embodiment of the present invention and referred to as a compact tensioner. The apparatus 600 is similar to the mooring apparatus 500 of FIG. 22(a), like parts being identified by like numerals, but iterated by “100”.

[0349] FIG. 22 shows during tensioning a relatively large vale for internal (wrap) angle α where the first mooring line 610 is in contact with or touches the open channel 665.

[0350] FIG. 23 shows during tensioning a relatively small value for the internal angle α where the first mooring line is biased towards the guide portion 605 and away from the open channel 665. This can reduce the opportunity for chaffing of the first mooring line 610 on entry to the apparatus 500.

[0351] In both of FIGS. 22 and 23 the lock arrangement 615 is in an unlocked disposition and provided in an opposite side of the mooring line path 620 than the guide portion 605.

[0352] It should be noted that the lock arrangement 615 can be provided with a temporary (e.g. removable) or permanent counterweight.

[0353] Referring to FIG. 24, the apparatus 500 is shown with the first mooring line 610 tensioned. The lock arrangement 615 is in a locked disposition and at least partly provided on the mooring path 620 and engaged with the first mooring line 610. In particular a lock (or stopper) face of the lock arrangement 615 abuts a locked line.

[0354] Referring to FIG. 25, once tensioned as shown in FIG. 24, excess chain can be released (and allowed to drop down).

[0355] The apparatus 600 can invert into an in-service disposition.

[0356] It should be noted that the locked link is engaged with the guide portion 605 (or dynamic guide).

[0357] It should be noted that a first clouded link is in line with a idealised or virtual mooring line path.

[0358] Referring to FIG. 26, there is shown an apparatus 700 accordingly to an embodiment of the present invention and referred to as an “ultra-compact” tensioner. The apparatus 700 is similar to the apparatus 600 of FIGS. 22 to 25, like parts being identified by the numerals, but iterated by “100”.

[0359] FIG. 26 shown the mooring apparatus 700 in an in-service disposition similar to that of the apparatus 600 is shown in FIG. 25.

[0360] It should be noted that the locked link is engaged with the guide portion 605 (or dynamic guide).

[0361] It should be noted that a first loaded link is in line with an idealised virtual mooring line path.

[0362] Referring to FIG. 27(a), there is shown in further detail the apparatus 600 of FIGS. 22 to 25, and the positions of the locked link and first loaded link.

[0363] Referring to FIG. 27(b), there is shown in further detail the apparatus 600 of FIG. 26 and the positions of the locked link and first loaded link.

[0364] Referring to FIGS. 28(a) to (d), there are shown first to fourth apparatus according to embodiments of the present invention.

[0365] The first to fourth apparatus are similar to the mooring apparatus of FIG. 26, like parts being identified by like numerals bit iterated by “100” and suffixed “a” to “d” respectively.

[0366] FIGS. 28(a) to (d) shows the following apparatus:

TABLE-US-00001 Guide Portion Lock Arrangement Counterweight FIG. comprising comprising which is 28(a) Groove wheel Finger/pin type stopper Permanent 28(b) Groove wheel Finger/pin type stopper Temporary 28(c) Spur toothed wheel Yoke type stopper Temporary 28(d) Groove wheel Finger/pin type stopper Permanent

[0367] Referring to FIGS. 29(a) and (b) there are shown first and second combination of guide portions and lock members for use in embodiments of the present invention.

[0368] In the combination of FIG. 29(a), the guide portion comprises a spur/toothed wheel and the lock member comprises a yoke stopper which can mesh with the spurs/teeth of the spur/toothed wheel.

[0369] In the combination of FIG. 29(b), the guide portion comprises a groove wheel, i.e. a wheel having a circumferential groove and the lock member comprising a finger or pin type stopper which can mush with the circumferential groove. First and second outer members of the wheel are dispersed in parallel relation to one another and can comprise further teeth or spurs.

[0370] It will be appreciated that the guide portions, lock arrangement and counterweights showing in FIGS. 28(a) to (d) and FIGS. 29(a) and (b) can find utility in any embodiments of the present invention, e.g. the embodiments disclosed hereinbefore.

[0371] Referring to FIGS. 30(a) to (d), there is shown a series of schematic side views of an apparatus, generally described 800, according to the present invention. The mooring apparatus 800 is similar to mooring apparatus according to embodiments of the present invention hereinbefore disclosed.

[0372] The mooring apparatus 800 comprises a guide portion 805, a lock arrangement 815, a first mooring line path 820, a second mooring line path 821, and a tangent line T from the guide portion 805.

[0373] As can be seen in FIG. 30(c), in service, i.e. after tensioning of the first mooring line 810 and locking of the lock arrangement 815, the tangent line T aligns with a portion of the first mooring line path 820 extending upwards, i.e. to/from the structure to be moored and the second mooring line path 821 extending downwards, e.g. to an anchor point. Thus a continuous load path is provided.

[0374] Referring to FIGS. 31(a) to (d), there is shown a series of schematic side views of an apparatus, generally described 900. The apparatus 900 is similar to apparatus according to embodiments of the present invention, e.g. FIG. 26 hereinbefore disclosed.

[0375] The apparatus 900 is shown in FIGS. 31(a) to (d) in the same dispositions and acting in a similar way to the apparatus 800 as shown in FIGS. 30(a) to (d), respectively.

[0376] It will be noted that in the apparatus 800 of FIGS. 30(a) to (d), the locked link 811 and the first loaded link 812 are in the mooring line path 820 in service, i.e. when the first mooring line 810 has been tensioned. Also the locked link 811 is on the guide portion 805.

[0377] It will also be noted that in the apparatus 900 of FIGS. 31(a) to (d), only the first loaded link 912 is in the mooring line path 920 in service, i.e. when the first mooring line 910 has been tensioned. Also, the locked link 911 is on the guide portion 905.

[0378] It will be appreciated that the embodiments of the present invention hereinbefore described are given by way of example only, and are not meant to be limiting to the scope of the invention. Each of the disclosed embodiments provide the features recited in the statements of invention and in the appended claims, such not being recited herewith in full merely for reasons of brevity.