U.S. patent application number 17/357221 was filed with the patent office on 2021-12-30 for mooring equipment for use in in-line tensioning.
The applicant listed for this patent is Nick Atallah, Charlie O'Rourke. Invention is credited to Nick Atallah, Charlie O'Rourke.
Application Number | 20210403128 17/357221 |
Document ID | / |
Family ID | 1000005869695 |
Filed Date | 2021-12-30 |
United States Patent
Application |
20210403128 |
Kind Code |
A1 |
O'Rourke; Charlie ; et
al. |
December 30, 2021 |
MOORING EQUIPMENT FOR USE IN IN-LINE TENSIONING
Abstract
Systems and methods for tensioning mooring lines are provided.
The systems include an in-line tensioner that may include a
removable chainwheel, a tail chain disconnecting table configured
for disconnection of a tail chain and docking of an ROV, a chain
guide having low-friction pads that reduce frictional engagement
between the in-line tensioner and mooring chains, and a target link
stopper that is configured to stop movement of the mooring line at
a predetermined location, such that the mooring line has a
predetermined length and such that a predetermined link of the
mooring line is positioned within a gripping zone of latches of the
in-line tensioner.
Inventors: |
O'Rourke; Charlie; (Ventura,
CA) ; Atallah; Nick; (Goleta, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
O'Rourke; Charlie
Atallah; Nick |
Ventura
Goleta |
CA
CA |
US
US |
|
|
Family ID: |
1000005869695 |
Appl. No.: |
17/357221 |
Filed: |
June 24, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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63043403 |
Jun 24, 2020 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B63B 2021/505 20130101;
B63B 21/08 20130101; B63B 21/50 20130101; B63B 2021/008
20130101 |
International
Class: |
B63B 21/08 20060101
B63B021/08; B63B 21/50 20060101 B63B021/50 |
Claims
1. An in-line tensioner for tensioning mooring lines, the in-line
tensioner comprising: a frame, the frame configured to couple with
a bottom chain of mooring line; latches coupled with the frame, the
latches positioned to grip a top chain of mooring line; and a
chainwheel, wherein the chainwheel has at least two configurations,
the at least two configurations including a first configuration
wherein the chainwheel is coupled with the frame and is positioned
to guide a top chain of mooring line, and a second configuration
wherein the chainwheel is decoupled from the frame.
2. The in-line tensioner of claim 1, wherein the frame comprises a
chainwheel dock, the chainwheel dock configured to receive the
chainwheel in the first configuration.
3. The in-line tensioner of claim 2, wherein the chainwheel is
mounted on a chainwheel frame.
4. The in-line tensioner of claim 3, wherein in the first
configuration the chainwheel frame is pinned with the frame.
5. The in-line tensioner of claim 3, wherein the chainwheel frame
comprises pins, wherein the chainwheel dock comprises funnels, and
wherein, in the first configuration the pins are engaged within the
funnels and in the second configuration the pins are disengaged
from the funnels.
6. The in-line tensioner of claim 3, further comprising a
chainwheel handle coupled with the chainwheel frame, wherein the
chainwheel handle is configured to couple with a line for lifting
and removing the chainwheel from the frame.
7. The in-line tensioner of claim 3, wherein the chainwheel frame
comprises counterweights configured to maintain orientation of the
pins.
8. The in-line tensioner of claim 1, wherein, in the second
configuration, a center of gravity of the in-line tensioner is
below a chain line of the mooring line.
9. The in-line tensioner of claim 1, further comprising: a chain
guide coupled with the frame, the chain guide positioned to guide a
top chain of mooring line, wherein the latches are positioned
between the chainwheel and the chain guide when the chainwheel is
in the first configuration; and pads on the chain guide positioned
to slidingly engage with a top chain of mooring line, wherein the
chain guide comprises a first material and the pads comprise a
second material, wherein the first material and the second material
are different, and wherein the second material exhibits a lower
coefficient of friction relative to a top chain sliding along the
second material than a coefficient of friction exhibited by the
first material.
10. (canceled)
11. (canceled)
12. (canceled)
13. (canceled)
14. The in-line tensioner of claim 1, further comprising: a tail
chain disconnecting table integral with or coupled to the frame,
wherein the tail chain disconnecting table is configured to receive
and secure a tail chain of mooring line.
15. The in-line tensioner of claim 14, wherein the tail chain
disconnecting table comprises a tail chain locking pin for securing
a tail chain to the tail chain disconnecting table.
16. The in-line tensioner of claim 14, wherein the tail chain
disconnecting table is configured to receive and secure a tail
chain in a vertical orientation, a flat orientation, or a hanging
orientation.
17. The in-line tensioner of claim 16, wherein the tail chain
disconnecting table comprises a track configured to receive a tail
chain in a flat orientation and a slot configured to receive a tail
chain in a vertical orientation.
18. The in-line tensioner of claim 14, wherein the tail chain
disconnecting table comprises a remotely operated vehicle dock, the
remotely operated vehicle dock configured to receive and secure a
remotely operated vehicle.
19. The in-line tensioner of claim 18, wherein the remotely
operated vehicle dock comprises funnels configured to engage with
pins of a remotely operated vehicle.
20. A mooring system, the mooring system comprising: a mooring line
comprising a bottom chain and a top chain; an in-line tensioner
comprising a frame and latches coupled with the frame, wherein the
bottom chain is coupled with the frame, and wherein the latches are
positioned to selectively grip the top chain such that a length of
the top chain portion of the mooring line is adjustable; a
chainwheel, wherein the chainwheel has at least two configurations,
the at least two configurations including a first configuration
wherein the chainwheel is coupled with the frame and is positioned
to guide the top chain of mooring line, and a second configuration
wherein the chainwheel is decoupled from the frame; a target link
stopper coupled with the top chain, wherein the target link stopper
is positioned along the top chain such that when the target link
stopper engages the in-line tensioner the mooring line has a target
length.
21. The mooring system of claim 20, wherein, at the target length,
the target link stopper is positioned on an outboard side of the
latches and a removable link of the top chain is positioned on an
opposite side of the latches, wherein the removable link is a link
that is selectively removable from the top chain.
22. (canceled)
23. The mooring system of claim 20, wherein, at the target length,
the predetermined link of the top chain is positioned to be gripped
by the latches.
24. (canceled)
25. The mooring system of claim 20, wherein, with the top chain
moving in a first direction through the in-line tensioner,
engagement of the target link stopper with the in-line tensioner
prevents further movement of the top chain in the first
direction.
26. The mooring system of claim 20, wherein the target link stopper
comprises a first body and a second body, wherein the first and
second bodies are coupled to each other about a portion of the top
chain, and wherein a spring a coupled between the first and second
bodies.
27. (canceled)
28. A method of mooring a floating vessel, the method comprising:
providing an in-line tensioner comprising a frame, a chainwheel
coupled with the frame, and latches coupled with the frame;
providing a mooring line including a bottom chain and a top chain;
coupling the bottom chain between the frame and an anchor; coupling
the top chain with the chainwheel, and coupling a first end of the
top chain with the floating vessel; adjusting a length of the top
chain between the floating vessel and the in-line tensioner until
the mooring line has a target length, wherein the chainwheel guides
movement of the top chain during the adjusting; gripping the top
chain with the latches when the mooring line has the target length;
and removing the chainwheel from the in-line tensioner while the
mooring line has the target length.
29. The method of claim 28, wherein removing the chainwheel
comprises unpinning a chainwheel frame of the chainwheel from the
frame of the in-line tensioner, and lifting the chainwheel from the
in-line tensioner.
30. The method of claim 29, wherein lifting the chainwheel from the
in-line tensioner is performed using an anchor handling vessel.
31. The method of claim 28, further comprising: a chain guide
coupled with the frame, the chain guide comprising pads positioned
thereon; wherein, during the adjusting of the length of the top
chain, the top chain slides along the pads, wherein the chain guide
comprises a first material and the pads comprise a second material,
wherein the first material and the second material are different,
and wherein the second material exhibits a lower coefficient of
friction relative to the top chain sliding along the second
material than a coefficient of friction exhibited by the first
material.
32. (canceled)
33. (canceled)
34. (canceled)
35. The method of claim 28, further comprising: a tail chain
disconnecting table integral with or coupled to the frame; securing
a tail chain of the top chain to the tail chain disconnecting
table; and removing at least some of the tail chain from the top
chain.
36. (canceled)
37. (canceled)
38. (canceled)
39. (canceled)
40. (canceled)
41. (canceled)
42. (canceled)
43. (canceled)
44. The method of claim 28, further comprising: coupling a target
link stopper with the top chain, wherein the target link stopper is
positioned along the top chain such that when the target link
stopper engages the in-line tensioner the mooring line has the
target length; wherein adjusting the length of the top chain
between the floating vessel and the in-line tensioner is performed
until the target link stopper engages the in-line tensioner; and
wherein gripping the top chain with the latches is performed when
the target link stopper is engaged with the in-line tensioner.
45. (canceled)
46. (canceled)
47. (canceled)
48. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S.
Provisional Patent Application No. 63/043,403 (pending), filed on
Jun. 24, 2020, and entitled "Mooring Equipment for Use in In-Line
Tensioning," the entirety of which is incorporated herein by
reference.
FIELD
[0002] The present disclosure relates to systems and methods for
mooring vessels and tensioning mooring lines. In particular, the
present disclosure relates to systems and methods that use an
in-line tensioner to tension mooring lines.
BACKGROUND
[0003] In many applications, floating vessels require mooring, such
as in offshore drilling platform applications. The mooring lines
typically require at least some tensioning to securely moor the
vessel. One approach to mooring and tensioning includes the use of
a so called "in-line tensioner" ("ILT") to tighten mooring
lines.
BRIEF SUMMARY
[0004] Some embodiments of the present disclosure include an
in-line tensioner for tensioning mooring lines.
[0005] In some embodiments, the in-line tensioner includes a frame
configured to couple with a bottom chain of mooring line, latches
coupled with the frame and positioned to grip a top chain of
mooring line, and a chainwheel. The chainwheel has at least two
configurations. The at least two configurations include a first
configuration with the chainwheel coupled with the frame and
positioned to guide a top chain of mooring line, and a second
configuration with the chainwheel decoupled from the frame.
[0006] In some embodiments, the in-line tensioner includes a frame
configured to couple with a bottom chain of mooring line, latches
coupled with the frame and positioned to grip a top chain of
mooring line, a chainwheel coupled with the frame and positioned to
guide a top chain of mooring line, and a chain guide coupled with
the frame and positioned to guide a top chain of mooring line. The
latches are positioned between the chainwheel and the chain guide.
Pads are on the chain guide and positioned to slidingly engage with
a top chain of mooring line as the mooring line passes through the
in-line tensioner. The chain guide includes a first material and
the pads include a second material. The first material and the
second material are different materials. The second material
exhibits a lower coefficient of friction relative to a top chain
sliding along the second material than a coefficient of friction
exhibited by the first material relative to a top chain sliding
along the first material.
[0007] In some embodiments, the in-line tensioner includes a frame
configured to couple with a bottom chain of mooring line, latches
coupled with the frame and positioned to grip a top chain of
mooring line, a chainwheel coupled with the frame and positioned to
guide a top chain of mooring line, and a tail chain disconnecting
table integral with or coupled to the frame. The tail chain
disconnecting table is configured to receive and secure a tail
chain of mooring line.
[0008] Some embodiments of the present disclosure include a mooring
system that includes a mooring line having a bottom chain and a top
chain. The system includes an in-line tensioner having a frame and
latches coupled with the frame. The bottom chain is coupled with
the frame. The latches are positioned to selectively grip the top
chain such that a length of the top chain portion of the mooring
line is adjustable. The system includes a target link stopper
coupled with the top chain. The target link stopper is positioned
along the top chain such that when the target link stopper engages
the in-line tensioner the mooring line has a target length.
[0009] Some embodiments of the present disclosure include a method
of mooring a floating vessel.
[0010] In some embodiments, the method includes providing an
in-line tensioner having a frame, a chainwheel coupled with the
frame, and latches coupled with the frame. The method includes
providing a mooring line including a bottom chain and a top chain,
coupling the bottom chain between the frame and an anchor, and
coupling the top chain with the chainwheel. The method includes
coupling a first end of the top chain with the floating vessel. The
method includes adjusting a length of the top chain between the
floating vessel and the in-line tensioner until the mooring line
has a target length. The chainwheel guides movement of the top
chain during the adjusting. The method includes gripping the top
chain with the latches when the mooring line has the target length.
The method includes removing the chainwheel from the in-line
tensioner while the mooring line has the target length.
[0011] In some embodiments, the method includes providing an
in-line tensioner having a frame, a chainwheel coupled with the
frame, latches coupled with the frame, and a chain guide couple
with the frame. The chain guide has pads positioned thereon. The
method includes providing a mooring line including a bottom chain
and a top chain, coupling the bottom chain between the frame and an
anchor, and coupling the top chain with the chainwheel. The method
includes coupling a first end of the top chain with the floating
vessel. The method includes adjusting a length of the top chain
between the floating vessel and the in-line tensioner until the
mooring line has a target length. The chainwheel guides movement of
the top chain during the adjusting. The method includes gripping
the top chain with the latches when the mooring line has the target
length. The latches are positioned along the top chain between the
chainwheel and the chain guide. During the adjusting of the length
of the top chain, the top chain slides along the pads. The chain
guide includes a first material and the pads include a second
material. The first material and the second material are different.
The second material exhibits a lower coefficient of friction
relative to the top chain sliding along the second material than a
coefficient of friction exhibited by the first material.
[0012] In some embodiments, the method includes providing an
in-line tensioner having a frame, a chainwheel coupled with the
frame, latches coupled with the frame, and a tail chain
disconnecting table integral with or coupled to the frame. The
method includes providing a mooring line including a bottom chain
and a top chain, coupling the bottom chain between the frame and an
anchor, and coupling the top chain with the chainwheel. The method
includes coupling a first end of the top chain with the floating
vessel. The method includes adjusting a length of the top chain
between the floating vessel and the in-line tensioner until the
mooring line has a target length. The chainwheel guides movement of
the top chain during the adjusting. The method includes gripping
the top chain with the latches when the mooring line has the target
length. The method includes securing a tail chain of the top chain
to the tail chain disconnecting table, and removing at least some
of the tail chain from the top chain.
[0013] In some embodiments, the method includes providing an
in-line tensioner including a frame, a chainwheel coupled with the
frame, and latches coupled with the frame. The method includes
providing a mooring line including a bottom chain and a top chain,
coupling the bottom chain between the frame and an anchor, and
coupling the top chain with the chainwheel. The method includes
coupling a first end of the top chain with the floating vessel. The
method includes coupling a target link stopper with the top chain.
The target link stopper is positioned along the top chain such that
when the target link stopper engages the in-line tensioner the
mooring line has a target length. The method includes adjusting a
length of the top chain between the floating vessel and the in-line
tensioner until the target link stopper engages the in-line
tensioner. The method includes gripping the top chain with the
latches when the target link stopper is engaged with the in-line
tensioner.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] So that the manner in which the features and advantages of
the system, apparatus, products, and/or methods so of the present
disclosure may be understood in more detail, a more particular
description briefly summarized above may be had by reference to the
embodiments thereof which are illustrated in the appended drawings
that form a part of this specification. It is to be noted, however,
that the drawings illustrate only various exemplary embodiments and
are therefore not to be considered limiting of the disclosed
concepts as it may include other effective embodiments as well.
[0015] FIG. 1 depicts a mooring set up.
[0016] FIG. 2A depicts another mooring set up.
[0017] FIG. 2B depicts a detail view of the mooring set up of FIG.
2A.
[0018] FIG. 3 is a perspective view of an in-line tensioner.
[0019] FIG. 4 a top view of an in-line tensioner.
[0020] FIG. 5 is a side view of an in-line tensioner.
[0021] FIG. 6 is an end view of an in-line tensioner.
[0022] FIG. 7 is a perspective view an in-line tensioner with a
chain engaged therewith.
[0023] FIG. 8 depicts an in-line tensioner with the chainwheel
removed.
[0024] FIG. 9A is a perspective view of a target link stopper.
[0025] FIG. 9B is an end view of a target link stopper.
[0026] FIG. 9C is a side view of a target link stopper.
[0027] FIG. 9D is a cross sectional view of the target link stopper
of FIG. 9B along line A-A.
[0028] FIG. 9E is another perspective view of a target link
stopper.
[0029] FIG. 10A is a perspective view of a target link stopper
engaged with a chain guide.
[0030] FIG. 10B is a side view of a target link stopper engaged
with a chain guide.
[0031] FIG. 11 depicts an in-line tensioner having a chainwheel
attached thereto.
[0032] FIG. 12A depicts a tail chain secured on a tail chain
disconnecting table including a disconnecting link in a flat
orientation.
[0033] FIG. 12B depicts a tail chain secured on a tail chain
disconnecting table including a disconnecting link in a vertical
orientation.
[0034] FIG. 12C depicts a tail chain secured on a tail chain
disconnecting table including a disconnecting link in a hanging
orientation.
[0035] FIG. 13A depicts an in-line tensioner with a tail chain
secured to a tail chain disconnecting table.
[0036] FIG. 13B depicts the in-line tensioner of FIG. 13A, with the
chainwheel being lifted from the in-line tensioner.
[0037] FIG. 14 depicts an ROV docked at the tail chain
disconnecting table and removing a link therefrom.
[0038] FIG. 15 depicts an in-line tensioner coupled with a mooring
line and without a chainwheel thereon.
DETAILED DESCRIPTION
[0039] Certain aspects of the present disclosure include systems
and methods for mooring vessels and tensioning mooring lines. The
present disclosure includes systems and methods for mooring vessels
and tensioning mooring lines using or incorporating in-line
tensioning technology. Embodiments of the present disclosure
include an in-line tensioner that can be positioned in or along a
mooring line and used to tighten the mooring line. As described in
more detail below, embodiments of the in-line tensioner disclosed
herein include: (1) a removable chainwheel; (2) a chain guide with
low-friction pads that reduce frictional engagement with chains;
(3) a target link stopper for stopping movement of mooring lines at
predetermined locations; (4) a disconnecting table providing for
disconnection of tail chain from mooring lines; (5) or combinations
thereof.
Mooring Set Up
[0040] FIG. 1 depicts an exemplary mooring set up in which the
in-line tensioner systems and methods disclosed herein may be
applied. While FIG. 1 depicts moored wind turbine 12, the in-line
tensioner systems and methods disclosed herein are not limited to
use in mooring wind turbines, and may be used to moor other
structures, such as oil and gas drilling and production platforms,
ships, or other floating structures.
[0041] As shown, mooring set up 10 includes wind turbine 12 is
moored to seabed 14 via mooring line 16. Mooring line 16 includes
chain 18 (bottom chain) anchored to seabed 14. Chain 18 is coupled
with in-line tensioner 20. Mooring line 16 includes wire 22 (top
chain), which is coupled with in-line tensioner 20 opposite chain
18. Mooring line 16 includes H-links 24 coupled with wire 22, and
tri-plate 28 coupled with H-links 24 via chain 26. Chain, rope or
wire 30 (e.g., minimum breaking load chain) is coupled between
tri-plate 28 and replaceable strongpoints 32 of wind turbine
12.
[0042] FIGS. 2A and 2B depict another mooring set up, demonstrating
the use of an anchor handling vessel in the tensioning of a mooring
line. Mooring set up 34 includes mooring line 42 positioned to moor
wind turbine 48. Mooring line 42 includes anchor chain 44 (bottom
chain) coupled with chain 46 (top chain) via in-line tensioner 40.
Anchor handling vessel 36 is positioned to pull on wire or chain
38, which is coupled with in-line tensioner 40 and is coupled with
or integral with chain 46. Pulling on wire or chain 38 results in
the tensioning of chain 46; thereby, tensioning of mooring line
42.
[0043] The mooring set ups shown in FIGS. 1-2B are examples of
mooring set ups in which the systems and methods disclosed herein
may be used for mooring operations. One skilled in the art would
understand that the in-line tensioner systems and methods disclosed
herein may be used in other mooring set ups and arrangements.
In-Line Tensioner
[0044] Certain embodiments of the present disclosure include an
in-line tensioner. With reference to FIGS. 3-8, an in-line
tensioner in accordance with at least some embodiments of the
present disclosure is depicted. In-line tensioner 101 (also
referred to as ILT 101) is configured to receive coupled with a
mooring line, and to lock a position of the mooring line to provide
the mooring line with a desired tension and length. In-line
tensioner 101 includes frame 103. Frame 103 provides a latch
housing for latches of the in-line tensioner 101 and provides a
mount for mounting a chainwheel of the in-line tensioner 101. Frame
103 may be the primary body of the in-line tensioner 101.
[0045] Frame 103 is mounted on mud mat 107 (e.g., a skid). Mud mat
107 provides the in-line tensioner 101 with the ability to be moved
around a deck of an anchor handling vessel (AHV), such as by tugger
winches, and provides a structure to withstand loads induced when
deploying the in-line tensioner 101 over a stern roller of the
anchor handling vessel under tension, which can be up to 1000 kN.
The mud mat 107 also provides a surface of the ILT 101 that can be
placed on the seafloor. For example, the mud mat 107 can be placed
on the seafloor when attached with a mooring line that is pre-laid,
or the mud mat 107 can be placed on the seafloor while the mooring
line is being replaced.
[0046] ILT 101 is coupled with chain 135 (also referred to as
anchor chain or bottom chain). For example, chain 135 can be
fixedly coupled with frame 103 of ILT 101, such as via chain
connector 141. Chain connector 141 is coupled (e.g., pinned to via
a pin connection) with chain 135 and with frame 103 (at 103a) via
bushings 143. The bushings 143 may be composite bushings to provide
galvanic isolation. The bushings 143 may include a material that is
capable of withstanding full mooring load design (MBL of the
mooring line). In some embodiments, the bushings 143 include a
low-friction bearing material. In some embodiments, chain 135 is a
"passive chain connection," such that a length of chain 135 is not
adjustable (i.e., is passive). That is, with the chain 135 attached
at one end to an anchor and at the other end to the ILT 101, the
length of the chain 135 between the anchor and the ILT 101 is
static (does not change).
[0047] ILT 101 is coupled with chain 131 (also referred to as top
chain or work chain). The connection between ILT 101 and chain 131
is an "active chain connection," such that a length of chain 131 is
adjustable. That is, using an AHV in conjunction with the
chainwheel and latches of the ILT 101, the length and tension of
chain 131 is adjustable, providing for mooring of structures that
are coupled with chain. For example, an AHV can haul in or pay out
chain 131 to increase or decrease the tension on chain 131.
[0048] As shown in FIG. 7, the passive chain connection is located
at a bottom end of ILT 101, and the active chain connection is
located at a top end of the ILT 101, with the chainwheel 115
positioned between the passive chain connection and the active
chain connection. In some embodiments, the passive chain connection
includes an ROV operable pin connection (not shown) for
disconnecting the frame 103 from chain 135. Tension on the mooring
line can be removed to allow an ROV operable pin connection to be
safely and reliably released when desired.
Removable Chainwheel
[0049] ILT 101 includes removable chainwheel 115. While the
embodiment of chainwheel 115 shown in FIGS. 3-7 is a dual
chainwheel, the systems and methods disclosed herein are not
limited to use with dual chainwheels. Chainwheel 115 is mounted
(e.g., pinned) on frame 103 at locations 103b. In particular,
chainwheel 115 includes chainwheel mounting frame 153, which is
pinned with frame 103. Chainwheel 115 is rotatably mounted onto
chainwheel mounting frame 153 via chainwheel axle 152, such that
chainwheel 115 can rotate relative to chainwheel mounting frame
153.
[0050] The frame 103 can include a chainwheel dock configured to
receive and secure the chainwheel 115, such as funnels 159 and pins
157. Chainwheel mounting frame 153 includes stabbing pins 161.
Stabbing pins 161 are configured to engage within mating funnels
159 of frame 103. Thus, stabbing pins 161 and mating funnels 159
provide for engagement and disengagement between chainwheel
mounting frame 153 and frame 103. In some embodiments, the
chainwheel mounting frame 153 includes counterweights to facilitate
the stabbing pins 161 remaining in the desired orientation (e.g.,
vertical) as the chainwheel 115 is lowered into place onto the
frame 103 during installation of the chainwheel 115 onto the ILT
101. The chainwheel mounting frame 153 is pinned to the frame 103
via pins 157. The chainwheel and chainwheel frame is not limited to
the particular structure shown here, and may have other structures
capable of being selectively attached and detached from the ILT to
provide a removable chainwheel. Thus, the removable chainwheel 115
disclosed herein has at least two configurations. The at least two
configurations include a first configuration with the chainwheel
115 is coupled with the frame 103 and positioned to guide top chain
131, and a second configuration with the chainwheel 115 is
decoupled from the frame 103 and removed from the ILT 101.
[0051] In operation, the chainwheel 115 rotates, guiding the chain
131 as the chain 131 is hauled-in or paid-out (e.g., hauled in or
paid out via an AHV). In some embodiments, the chainwheel 115 has
one or more (e.g., two) wildcat profiles that have surface contours
designed to engage with the chain, and includes chain contact areas
shaped to follow (mate with) the shape of the chain links; thereby,
minimizing local stresses. In some embodiments, the chainwheel 115
is a dual chainwheel capable of engaging with and guiding at least
two different sized chains. In other embodiments, the chainwheel
115 is a single chainwheel designed for use with just one chain
size. In embodiments where the chainwheel 115 is a dual chainwheel,
the dual chainwheel is configured to provide for a seamless
transition from engagement with a smaller adjustment chain to
engagement with a mooring chain. For example, a connector (link
coupler) can connect the two different sized chains and engage with
the dual chainwheel to facilitate the transition between the chain
sizes. For example, and without limitation, the chainwheel 115 may
be the same as or similar to the chainwheel disclosed in U.S.
Patent Publication No. 2019/0092599 (the '599 Publication), the
entirety of which is incorporated herein by reference. Also, the
link coupler disclosed in the '599 Publication may both be used to
connect the smaller adjustment chain with the larger mooring chain.
Use of the link coupler and dual chainwheel can ensure that the two
different chain sizes stay "clocked" on the chai wheel 115 and fall
into the appropriate pockets of the chainwheel 115 for chain
support; thereby, at least reducing bending on the chain links.
[0052] In some embodiments, the chainwheel 115 includes two
self-lubricating bushings that minimize rotating resistance
relative to the mounting frame 153, without requiring the use of
external grease lubrication.
[0053] Handle 173 is coupled with chainwheel mounting frame 153. In
operation, handle 173 may be used to manipulate (e.g., move)
chainwheel 115 and chainwheel mounting frame 153, such as for
installation onto frame 103 and for removal from frame 103. For
example, a wire, rope or chain of a winch or crane (e.g., on an
AHV) may engage with handle 173 to lift chainwheel 115 and
chainwheel mounting frame 153 from frame 103 or to lower chainwheel
115 and chainwheel mounting frame 153 onto frame 103. The ability
to easily remove and reattach chainwheel 115 allows for removable
of chainwheel 115 to reduce weight of the ILT 101 when the
chainwheel 115 is not in use, and allows for the reattachment of
the chainwheel 115 for operations, such as to haul-in or pay-out
chain. Reducing the weight of the ILT 101 provides for better
long-term performance of the ILT 101; reduces the number of moving
parts left in the water column, reducing concerns over marine
growth and corrosion; shifts the center of gravity of the ILT 101
to a position below the chain line of action so that there is
reduced occurrence of twisting of the mooring line after
tensioning; provides for better maintainability of moving parts
(e.g., chainwheel bearings); or combinations thereof. As used
herein, the "chain line" is an imaginary line that is coincident
with the extension of the mooring line. Thus, with the center of
gravity of the ILT 101 below the chain line, the center of gravity
of the ILT 101 is closer to the seabed than the chain line.
[0054] The removability of chainwheel 115 also allows the
chainwheel 115 to be used and re-used with multiple different
in-line tensioners, reducing the total number of chainwheels 115
needed for mooring operations and, thus, reducing the overall cost
of mooring operations. The funnels 159 and pins 161 provide for the
easy docking of the chainwheel 115 onto the frame 103, as aligning
the pins 161 with the funnels 159 and inserting the pin 161 into
the funnels ensures that the chainwheel 115 is docked at the
correction location and in the correct orientation. Additionally,
the pins 157 that secure the docked chainwheel 115 to the frame 103
can be ROV operable, providing easy securement of the chainwheel
115 to the frame 103. The reverse operation of the pins 157, pins
161, and funnels 159 provide for ease of removal of the chainwheel
115 from the frame.
Chain Guide with Low-Friction Pads
[0055] ILT 101 includes chain guide 117. Chain guide 117 is
positioned and configured to guide chain 131 into ILT 101 towards
the latches thereof. Chain guide 117 may be a tapered funnel that
guides chain. Guide 117 may be useful if, for example, the chain is
laterally misaligned from the ILT 101 and simultaneously rotated
(e.g., up to approximately 20 degrees). Chain guide 117 and frame
103 are equipped with anodes 119, which provide for cathodic
protection. Chain guide 117 (chain guide shoe) is positioned at the
outboard end of frame 103. In the embodiment shown, chain guide 117
is a double "V" shaped funnel that contacts the chain links to
assist in leading the chain properly into the chainwheel 115 and
latches 145 during the hauling-in of the chain. However, the chain
guide disclosed herein is not limited to this particular
embodiment.
[0056] Chain guide 117 includes low-friction pads 118 thereon.
Low-friction pads 118 are positioned to engage with chain 131
passing through chain guide 117. Low-friction pads 118 exhibit
reduced friction when the chain 131 slides along a surface of the
low-friction pads 118 during hauling in or paying out in comparison
to the degree of friction that would be exhibited by the chain 131
sliding along a surface of the underlying chain guide 117 (without
the low-friction pads 118 thereon). For example, the low-friction
pads 118 can include a material that is different than the material
of the underlying chain guide 117. In some embodiments, the
low-friction pads 118 include a material that is different than the
material of the chain 131. The material of the low-friction pads
118 can be a material that exhibits a lower coefficient of friction
with the mooring chain 131 as the chain 131 slides along the
low-friction pads 118, in comparison to the coefficient of friction
that would be exhibited by the material of the underlying chain
guide 117 if the mooring chain 131 were sliding along the material
of the underlying chain guide 117. In some embodiments, the chain
guide 117 and the mooring chain 131 both include the same material,
such as steel. Without being bound by theory, a steel mooring chain
sliding along plate steel of a chain guide, in seawater, typically
exhibits a CoF of from 0.25 to 0.5. Thus, the CoF of a steel
mooring chain sliding along the low-friction pads 118, in seawater,
may be less than 0.5, or less than 0.25, or less than 0.2. By
reducing the friction of engagement between chain 131 and chain
guide 117, low-friction pads 118 reduce tendency for the ILT 101
and chain catenary to repeatedly rise and fall as the chain 131 is
hauled up from an AHV. That is, the low-friction pads 118 reduce
friction during tensioning of the mooring line and, thus, reduce
the tendency to repeatedly lift and drop the ILT 101 due to static
friction of the chain rubbing on the chain guide 117. The reduction
in friction provided by low-friction pads 118 at the chain guide
117 interface with chain 131 facilitates better control of the
mooring operation in comparison with an otherwise identical ILT
without the low-friction pads 118.
Latches
[0057] Chain guide 117 guides chain 131 to latches 145 of ILT 101.
Latches 145 are, or from a part of, a chain stopper of ILT 101.
Latches 145 are coupled with frame 103 and positioned to engage
with chain 131 passing through ILT 101. Latches 145 are operable to
open, such that the latches 145 are clear of the chain links
passing through ILT 101. Latches 145 are also operable to close,
such that the latches 145 engage with (latch upon) the chain links
passing through ILT 101. In some embodiments, latches 145 are
rotatable to change the orientation of the latches 145 relative to
the extension of the chain, such that the latches 145 can rotate to
engage both vertical links and flat links. As used herein, "flat
links" and "vertical links" refer to adjacent links on a chain that
are oriented 90 degrees or substantially 90 degrees from one
another, as would be well understood by one of ordinary skill in
the art. For example, U.S. Pat. No. 10,272,973 (the '973 Patent)
discloses a rotatable chain stopper capable of rotating latches to
engage both flat and vertical links. In some embodiments, the
latches disclosed herein are the same as or similar to the
rotatable latches disclosed in the '973 Patent, the entirety of
which is incorporated herein by reference. In some embodiments, the
latches 145 include latch pawls that contain machined contoured
pockets configured and shaped to cradle the chain links, thus,
maximizing the chain contact surface and reducing chain wear. In
some embodiments, the latches 145 are rotatable latches that permit
various orientations of the chain; thereby, reducing off center
forces on the latches 145 and the chain. In some embodiments, the
latches 145 include a material that has a lower hardness than the
material of the chain to ensure that the chain sets into the
latches 145 and that local yielding that may occur will be on the
latches 145 and not the chain.
[0058] The latches 145 can be mechanically opened by the chain as
the chain is hauled-in. The embodiment shown includes two latches
145 that are mechanically linked to synchronize their movement via
synchronizing linkage 127. The closing force of the latches 145 may
be provided by mechanical springs 125 (latch closing spring) that
are coupled therewith and bias the latches 145 closed. Alternative
methods for providing the closing force of the latches 145 include
use of a counterweight, pneumatic or hydraulic springs, or a
combination of these methods depending on the particular
application. In some embodiments, an ROV can be used for remote
operation of the latches 145, a diver can operate the latches 145,
or a mechanical wire routed to an AHV above can operate the latches
145. For example, the latches 145 can be pinned in the open
position (clear of the chain) by an ROV or diver during chain
pay-out of the chain, if desired.
[0059] ILT 101 includes latch lock 121 for locking a position of
latches 145, and latch open handle 123 for opening latches 145. In
one exemplary embodiment, to pin the latches 145 in the open
position, an ROV is operated to twist latch lock pin 121; thereby,
actuating the lock open mechanism. When the latches 145 are opened,
the latches 145 can automatically lock in the open position.
Latches 145 can be opened by an ROV after chain tension has been
removed or by hauling the chain in a short distance (e.g., less
than one chain pitch, or about one and a half chain links) until a
first link contacts the bottom of the latches 145 and pushes the
latches 145 into the open position, at which point the lock open
mechanism maintains the latches 145 open for chain pay-out. When
chain pay-out is complete, an ROV can be operated to pull on the
latch lock 121 handle to disengage the latch lock 121, and the
latches 145 will close, automatically. In some embodiments of the
in-line tensioner 101, remote operation of the latches 145 can be
controlled by a hydraulic cylinder mounted to the frame 103 and
controlled by hoses and/or piping that is routed to a deck above or
controlled by acoustic and/or radio remote (e.g., a deck of an
AHV).
[0060] In some embodiments, latches 145 are designed to stop a
mooring chain in a manner that reduces chain stress by supporting
the chain on two contoured latches. The in-line tensioner 101
disclosed herein has a hold capacity that is equal to the mooring
line minimum breaking load (MBL).
Chain Disconnecting Table
[0061] ILT 101 includes tail chain disconnecting table 109. Tail
chain disconnecting table 109 is a structure configured to receive
and secure the tail chain of chain 131 and provide structure for
the disconnection or cutting of the tail chain portion of the chain
131. In some embodiments, tail chain disconnecting table 109
includes a docking station configured to receive and secure an ROV
for use in disconnection of the chain. For example, tail chain
disconnecting table 109 can include funnels or tubes 111 configured
to receive docking or stabbing pins of an ROV, such that the ROV
can dock onto ILT 101 for chain disconnection operations. One
skilled the art would understand that the funnels or tubes can be
on the ROV and stabbing pins on the tail chain disconnecting table
109. One skilled in the art would also understand that the tail
chain disconnecting table can include other structures capable of
receiving and securing an ROV, and is not limited to including pins
and funnels.
[0062] The tail chain disconnecting table 109 can be used to
disconnect tail chain from the mooring line. In some embodiments,
after tensioning of the mooring line, the remaining tail chain
(adjustment chain or work chain) is disconnected to reduce weight
in the catenary, minimize twist in the mooring line, and eliminate
complications for future reconnection due to having a long tail
chain hanging in the water column. Prior to disconnecting the tail
chain, the tail chain is laid onto the tail chain disconnecting
table 109 of the ILT 101 and secured thereto, such as by an ROV
operated pin. For example, when positioned on tail chain
disconnecting table 109, chain 131 can be pinned via chain locking
pin 129. Once the tail chain is pinned or otherwise secured to the
tail chain disconnecting table 109, an ROV docked on the tail chain
disconnecting table 109 can operate to remove at least a portion of
the tail chain. Removal of at least a portion of the tail chain can
include cutting a link of the tail chain, or removing a D-link (or
other removable link) of the tail chain.
[0063] In some embodiments, the tail chain disconnecting table 109
is positioned outside of the chain line such that operations for
removing tail chain can be performed outside of the chain line. For
example, as shown in FIG. 7, tail chain disconnecting table 109
arcs upwards from the chain line (imaginary line that is coaxial
with chains 131 and 135).
Target Link Stopper
[0064] Some embodiments disclosed herein include a target link
stopper (TLS). With reference to FIGS. 9A-9E, one embodiment of the
target link stopper 113 (TLS 113) is depicted. TLS 113 is a
configured to be attached to the top, work chain of the mooring
line at a predetermined location along the chain, and to stop
travel of the chain at the desired length and tension during
tensioning of the mooring line. For example, the TLS 113 can be
positioned to stop the tensioning of the mooring line such that a
predetermined chain link of the mooring line is positioned to be
gripped by the latches 145 of the ILT 101. The TLS 113 can be
positioned to stop the tensioning of the mooring line such that a
predetermined chain link of the mooring line is positioned on the
tail chain disconnecting table 109 to be cut or removed. In
operation, if the ILT 101 overruns past the correct link, then it
may be required to pay-out additional chain to return to the
correct mooring line length. The TLS 113 can, thus, prevent or
reduce overrunning of the chain.
[0065] TLS 113 includes first body end 122 coupled with (e.g.,
pinned to) second body end 124. TLS 113 may be included two
portions pinned together. For example, body portion 133a may be
pinned with body portion 133b via pin 126, and hinged via hinge
137, such that body portions 133a and 133b can opened (partially
separated) by pivoting about hinge 137 and be secured about a
mooring line, and then closed about the mooring line and pinned
thereto via pin 126. TLS 113 has spring-loaded mechanisms,
including springs 165 positioned within mated chambers 132 and 134.
Each spring 165 is configured to absorb impact loads on the TLS
113, such that upon impact of TLS 113 with ILT 101, each spring 165
compresses and the second body end 124 moves toward the first body
end 122. Each spring 165 is contained within matted chambers 132
and 134 of the first and second body ends 122 and 124,
respectively. TLS 113 includes crush pads 167 positioned on the TLS
113 to interface engagement between the TLS 113 and ILT 101. The
crush pads 167 aid in absorbing impact loading on TLS 113.
[0066] In some embodiments, the TLS 113 is ROV compatible such that
the TLS 113 can be installed, removed and re-installed, before or
after deployment, using an ROV.
[0067] With reference to FIGS. 10A and 10B, a spring-loaded TLS 113
is depicted engaged with chain 131 and ILT 101. TLS 113 is
positioned on chain 131, prior to deployment and tensioning
operations. Removal of pin 126 allows TLS 113 to be removed (e.g.,
using an ROV) after operations are completed. With TLS 113 attached
to the desired location on chain 131, TLS 113 acts as a stop on
chain 131 by engaging with ILT 101 (e.g., with chain guide 117).
The chain guide 117 interfaces with the TLS 113 to accommodate and
mitigate impact loading. When TLS 113 engages with ILT 101, at
least some compression of TLS 113 may occur as a result of
compression of the springs (springs 165) of TLS 113. Engagement of
TLS 113 with ILT 101 stops further movement of chain 131, such that
the desired link of the chain 131 is positioned within ILT 101 to
be latched therein (by latches 145), and such that the mooring line
has the desired length and/or tension. That is, TLS 113 can be
positioned along chain 131 to stop movement of the chain 131 at a
point when a predetermined link of the chain 131 is positioned
within a gripping zone of the latches 145. The "gripping zone," is
a position where, when the latches 145 enter the closed position, a
chain link positioned in the gripping zone is gripped and latched
by the latches 145.
[0068] In some embodiments, the TLS 113 has a mating geometry that
corresponds with the geometry of the ILT 101, such that surface
contact faces of the TLS 113 and the ILT 101 are matched to spread
the load over a larger surface area. In some embodiments, TLS 113
has a shape and/or size such that TLS 113 cannot pass through chain
guide 117, preventing further tensioning of mooring line upon
engaging of TLS 113 with chain guide 117.
[0069] One skilled in the art would understand that the target link
stopper disclosed herein is not limited to the particular structure
shown in FIGS. 9A-10B, and may include other structures that are
capable of being coupled with a mooring line and of stopping
tension of the mooring line upon engagement between the target link
stopper and an in-line tensioner.
Operation
[0070] Operation of the ILT 101 in the tensioning of a mooring line
will now be described. With reference to FIG. 11, ILT 101 is
depicted coupled with chain 135. Chain 135 extends to an anchor
(not shown) at the seabed (not shown). ILT 101 is also coupled with
chain 131, including upper portion 131a and lower portion 131b.
Upper portion 131a extends from ILT 101 to the structure (not
shown) being moored (e.g., a wind tower). Lower portion 131b
extends from ILT 101 to an anchor handling vessel (not shown). In
operation, the anchor handling vessel hauls in or pays out chain
131 by reeling in or releasing chain 131. Once a desired length of
chain 131 and/or tension on chain 131 is achieved, the latches of
the ILT 101 are used to latch upon the chain 131 to lock the
position of the chain 131 relative to the ILT 101. In some
embodiments, the desired length of chain 131 and/or tension on
chain 131 is determined to be present when the target link stopper
engages with the ILT 101, as shown in FIGS. 10A and 10B.
[0071] While the chainwheel 115 is exposed to mooring line tension
during tensioning operations, the mooring load is reacted by the
latches 145. During mooring operations, the chainwheel 115 can be
configured to pass an LLLC.RTM. connecting link and a messenger
chain, thus, satisfying the needs of a variety of mooring,
tensioning, and re-tensioning operations. The pretension loads
reacted by the chainwheel 115 are, typically, relatively low in
comparison with the MBL of the mooring line that the latches 145
bear (or are designed to bear). The chain tension on the chainwheel
115 is removed when the latches 145 are engaged with the chain in
the closed position (i.e., latched onto the chain).
[0072] With reference to FIGS. 12A-12C, after latching the chain
131 with the latches of ILT 101, the lower portion of the chain
131b (tail chain) is laid upon the tail chain disconnecting table
109 and pinned via pin 129. In some embodiments, the pinning of the
chain 131b to the table 109 is performed using an ROV that is
docked on the table 109. The lower portion of the chain 131b
includes a removable link 130a-130c. The removable link 130a-130c
is a chain link that can be opened and closed, such that the
removable link 130a-130c can be selectively attached and detached
from the remainder of the chain 131. For example, the removable
link 130a-130c may be a D-link or the like. Removable link 130a is
shown in a flat orientation on table 109 in FIG. 12A, with link
130a positioned on track 114. Removable link 130b is shown in a
vertical orientation on table 109 in FIG. 12B, with link 130b
positioned in slot 112. Removable link 130c is shown in a hanging
orientation on table 109 in FIG. 12C, extending upwards from table
109. The removable link can be passed through the ILT 101 and
around the chainwheel 115 in a vertical or flat orientation, giving
a mooring installation contractor the ability to choose which
orientation is preferred for removal after tensioning.
[0073] With reference to FIGS. 13A and 13B, when the end of the
chain 131b is pinned into place on the tail chain disconnecting
table 109, the chainwheel 115 can be removed from the ILT 101, such
as by removing two ROV compatible pins on each side of the
chainwheel 115 and then hauling the chainwheel 115 up using an AHV.
Chainwheel 115 can be disconnected from frame 103 of ILT 101 and
lifted therefrom. For example, wire 175 can be lowered, such as
from a winch or crane on an AHV. Wire 175 can include a hook 176
that engages with handle 173 for lifting chainwheel 115.
[0074] The chain disconnecting table 109 provides a structure where
the chain 131b can be positioned and secured, and provides a dock
for an ROV to engage the tail chain disconnecting table 109 to
disconnect the chain 131b. To make the operation easier and to
stabilize the ROV during disconnection of the chain, the dock of
the tail chain disconnecting table 109 includes interface funnels
111 that can include locking features for engagement with and
locking with an ROV. The interface funnels 111 allow an ROV to be
docked onto the tail chain disconnecting table 109. The ROV docking
interface funnels 111 are positioned on both sides of the
disconnecting table 109 to provide options to the ROV operator to
approach from either side of the ILT 101. As the manipulators of
the ROV are not required for holing the ROV onto the table 109, all
manipulators of a docked ROV may be free for use in disconnecting
the tail chain (rather than using one of the ROV manipulators to
hold onto the disconnecting table 109). The docking of the ROV
allows the ROV to easily control the chain locking pin 129 as it is
removed so that it is not dropped. The chain locking pin 129 on the
disconnecting table 109 is used to facilitate the disconnecting
operations. The chain locking pin 129 can be guided and captured by
the ROV so there is reduced risk of dropping the chain locking pin
129. The chain locking pin 129 is positioned outside of the mooring
load path and can be configured to meet corrosion requirements for
the life of the mooring line. The chain locking pin 129 locks a
position of the chain 131 onto the disconnecting table 109 by being
pinned over a link of the chain 131.
[0075] With reference to FIG. 14, the chainwheel 115 is removed
from the ILT 101 and ROV 201 is docked onto table 109 for
operations to disconnect the removable link of chain 131 from the
remainder of chain 131. Stabbing pins 203 of ROV 201 are engaged
within funnels 111. The removable link 130 provides for the
disconnection of the work chain 131 from the mooring chain after
tensioning is completed. As the final mooring length can be
calculated accurately (e.g., using the target link stopper 113),
the position of the link 130 of the chain 131 can also be
calculated accurately, such that the link 130 can be installed at
the correct location along the chain 131. The link 130 may be
removed by removing pin 171 threaded into the 130 (e.g., threaded
using ACME threads which offer high strength and are self-locking
so the pin will not tend to unthread itself). This removal of pin
171 can be accomplished using ROV 201. For additional security, a
safety wire (not shown) can be used to ensure that the pin 171 is
maintained fully threaded during operations. In such embodiments,
prior to removing the pin 171, the ROV 201 may be used to cut the
safety wire. In one example, the end of the pin 171 has an internal
hex cavity that matches a male drive bit that is attached to an ROV
torque tool. The ability to rigidly connect the ROV 201 to the
table 109 via funnels 111 and pins 203 allows the ROV 201 to safely
use a torque tool. That is, the ability to rigidly connect the ROV
201 to the table 109 via funnels 111 and pins 203 (or other docking
structures) prevents or reduces "swimming" by the ROV 201 while
performing the disconnection task, such that the ROV 201 is static
or substantially static relative to the ILT 101 during
disconnection of the link 130. In some embodiments, when one
manipulator 205a of the ROV 201 is used to removes pin 171 using a
torque tool, another manipulator 205b of the ROV 201 can be used to
capture the pin 171, such that there is a reduced chance of the pin
171 being dropped onto the seabed. While disconnection of the tail
chain is described as involving removing a removable link, in other
embodiments a link may be cut from the work chain. For example, an
ROV may operate a cutting tool to cut a link of the work chain.
[0076] If the work chain 131 is installed into an ILT 101 on board
an AHV before deployment, the orientation of the chain links can be
preselected. The ILT 101 of the present disclosure can accommodate
any orientation of chain links. Thus, using the ILT 101 of the
present disclosure, a mooring installation contractor can decide
which chain link orientation is most convenient for use in the
particular application and circumstances, and is not limited to
ensuring that the chain line has a particular orientation. Thus,
the ILT 101 of the present disclosure has a flexibility of design
that accommodates multiple positions for disconnection of the tail
chain.
[0077] FIG. 15 depicts the ILT 101 incorporate into a mooring line,
connecting chain 131a with chain 135, and with chain portion 131b
pinned thereto via pin 129.
[0078] If, after mooring line tensioning is completed, paying-out
of additional chain is required, an ROV connecting link can connect
back onto the last exposed link of the work chain that is left on
the chain disconnecting table 109. The disconnecting table 109 is
configured such that the last link of the chain can be reconnected
in either orientation (i.e., vertical or flat) in such a way as to
be available and accessible for reconnection. Three different
options for connecting link orientation and position are shown in
FIGS. 12A-12C, as discussed above. With the chain 131 and chain 135
connected on an AHV prior to deployment, the decision can be made
as to which orientation is best and easiest for future reconnection
prior to deployment. As shown, the disconnecting table 109 includes
a slot 112 for receipt of vertical links, and tracks 114 for
receipt of flat links. However, the disconnecting table 109 is not
limited to these particular structures, and may include other
structures for receipt of and securing of chain links of vertical
or flat orientation.
[0079] Another feature of flexibility in configuration of the
disconnecting table 109 is that, if there is a need to disconnect
additional length of chain (e.g., if more chain needs to be
hauled), then an underwater diamond saw chain cutter can be used,
optionally with modifications. For example, stabbing pins or other
docking structures may be incorporated on the cutter to dock with
(interface with) the receiving funnels 111 or other docking
structures on the disconnecting table 109. Thus, the disconnecting
table 109 provides a structure where the work chain 131 can be
secured, and can serve as a docking station for either an ROV to
perform disconnection or a chain cutter using a diamond wire
saw.
Floating Vessels
[0080] In some embodiments, the mooring methods and equipment
disclosed herein are used to more vessels of various types, such as
an oil drilling or production platforms, floating production
storage offloading (FPSO) vessels, offshore floating wind power
foundations, floating fish farms, or any other offshore floating
structure. The AHV disclosed herein may be a ship including one or
more winches, cranes, shark jaws, stern rollers, ROVs, and other
devices that may be used in the mooring of a vessel.
Mooring Line
[0081] The mooring lines disclosed herein may include one or more
sections of line, each of which may be composed of the same
material or of different materials. The various segments of mooring
lines may be coupled together via shackles, H-Links or other
connectors. The bottom chain 135 may be a pile forerunner coupled
with an anchor at seafloor. The anchor may be a suction pile,
driven pile, drag embedment anchor, gravity anchor, torpedo anchor,
or another type of anchor positioned at seafloor. The bottom chain
135 may be pre-laid and wet stored on the seafloor at the site,
prior to towing the vessel to the site, or may be laid on the
seafloor after towing the vessel to the site.
[0082] In some embodiments, the in-line tensioner disclosed herein
is configured to use a work chain that is smaller than the mooring
line chain to tighten the mooring line, while saving weight and
cost.
[0083] While specific embodiments and equipment are shown and
described herein, one skilled in the art would understand that the
methods, systems, and apparatus disclosed herein are not limited to
these particular embodiments described.
[0084] Although the present embodiments and advantages have been
described in detail, it should be understood that various changes,
substitutions and alterations can be made herein without departing
from the spirit and scope of the disclosure. Moreover, the scope of
the present application is not intended to be limited to the
particular embodiments of the process, machine, manufacture,
composition of matter, means, methods and steps described in the
specification. As one of ordinary skill in the art will readily
appreciate from the disclosure, processes, machines, manufacture,
compositions of matter, means, methods, or steps, presently
existing or later to be developed that perform substantially the
same function or achieve substantially the same result as the
corresponding embodiments described herein may be utilized
according to the present disclosure. Accordingly, the appended
claims are intended to include within their scope such processes,
machines, manufacture, compositions of matter, means, methods, or
steps.
* * * * *