Note: Descriptions are shown in the official language in which they were submitted.
CA 02331176 2006-02-23
METHOD AND APPARATUS FOR SUCTION ANCHOR AND
MOORING DEPLOYMENT AND CONNECTION
FIELD OF THE INVENTION
This invention relates generally to mooring line connections for subsea
operations,
particularly for suction anchor pile moorings. More particularly, this
invention concerns a wire
socket connector mechanism which facilitates subsea connection and
reconnection of mooring
lines of semi-submersible drilling rigs, production and drilling platforms and
the like to suction
anchor piles and other anchor devices. This invention also concerns deployment
and installation
of suction anchor piles and a mooring wire assembly with retrieval buoys and
sling on one of its
ends. The invention also concerns addition of buoys to mooring wire sections
and connecting
the mooring wire to a vessel to be moored. The procedure also concerns the
mooring wire, buoy
recovery, wire retrieval and suction anchor pile recovery and a procedure for
recovering mooring
wires and other apparatus.
BACKGROUND OF THE INVENTION
Floating offshore structures require some form of mooring to the seabed by an
anchor.
Various types of anchors have been used, including but not limited to
different drag embedment
anchors and those known as suction pile anchors. A key aspect of the mooring
process is
properly positioning the anchor in a desired location on the sea floor, and
connecting the floating
marine structure to the anchor.
Prior art mooring methods required multiple vessels to launch, lower, and
place the
anchors. Prior art methods further generally required that the anchor be
deployed when the
floating structure was on site, i.e. attached at the time of anchor deployment
to the anchor.
It can be well understood that the cost of offshore operations is very high,
and
considerable incentive exists to develop apparatus and methods to utilize only
a single vessel to
deploy subsea anchors. Further, considerable incentive exists to enable
operations to deploy
anchors in desired locations, in advance of the placement of the floating
structure, while still
being able to connect the floating structure to the anchor once the floating
structure is on site.
The apparatus and method of the present invention address these problems.
CA 02331176 2006-02-23
-2-
BRIEF DESCRIPTION OF THE DRAWINGS
The various objects and advantages of this invention will become apparent to
those skilled
in the art upon an understanding of the following detailed description of the
invention, read in
light of the accompanying drawings which are made a part of this specification
and in which:
In the drawings:
FIG. 1 is a plan view showing the stern section of an anchor handling vessel
designed for
suction anchor deployment, mooring wire deployment and handling and showing
four suction
anchors in loaded position on the stern of the vessel in preparation for
deployment thereof;
FIG. 2 is a plan view similar to that of FIG. 1 and showing one of the suction
anchors
having been maneuvered to its deployment position with respect to the stern
roller of the vessel
in preparation for suction anchor deployment;
FIG. 3 is a plan view of a track roller assembly for on deck handling of a
suction anchor
pile for deployment or retrieval operations;
FIG. 4 is an elevational view of the track roller assembly of FIG. 3;
FIG. 5 is a partial plan view of the track roller assembly of FIG. 3 showing
the top and
bottom roller arrangements thereof in detail;
FIG. 6 is an end elevational view of the track roller assembly of FIGS. 3-5
and showing
a hydraulic jacking mechanism for lateral movement of the track roller
assembly;
FIG. 7 is a plan view similar to that shown in FIGS. 1 and 2 and showing I-
beam tracks
mounted on the anchor handling vessel deck to permit transverse movement of
track rollers
during deployment or recovery operations for suction anchor piles;
FIG. 8 is side elevational view of a service vessel showing a suction anchor
pile in
position for launching over the stem roller of the vessel and showing an
initial arrangement of
handling lines;
FIG. 9 is a side elevational view similar to that of FIG. 8 and showing
overboarding of
the suction anchor pile and also showing the relationship of the handling
lines to the anchor
handling vessel and the suction anchor pile;
FIG. 10 is a side elevational view similar to that of FIG. 9 and showing the
suction anchor
pile leaving the stem roller of the vessel in route to its proposed site in
the sea floor;
CA 02331176 2006-02-23
-3-
FIG. 11 is a side elevational view similar to that of FIG. 10 and showing the
suction
anchor pile just under the stem of the vessel and further showing
disconnection of the
overboarding hook from the sling of the suction anchor pile by remote
operating vehicle (ROV)
handling;
FIG. 12 is a side elevational view similar to that of FIG. 11 and showing the
suction
anchor pile being lowered with a mooring wire to a point near the sea floor;
FIG. 13 is a side elevational view of the anchor handling vessel similar to
that of FIG.
12 and showing self-penetration of the suction anchor pile into the sea floor
with the ROV
monitoring and directing orientation of the suction pile and having the
capability to assist in
suction pile installation;
FIG. 14 is a side elevational view similar to that of FIG. 13 showing a
further step in
suction anchor pile deployment as water is evacuated from the suction anchor
pile by the ROV;
FIG. 15 is a side elevational view similar to that of FIG. 14 showing the
suction anchor
pile fully deployed and showing release of the hook of the lowering line from
the suction anchor
pile by ROV assistance;
FIG. 16 is a side elevational view similar to that FIG. 15, showing the
suction anchor
being connected to the main mooring extension wire which is suspended
substantially vertically
from the vessel to the suction anchor and showing movement of the
lowering/mooring wire from
the suction anchor pile support and reconnection of the mooring wire to the
main mooring wire
extension of the suction anchor pile;
FIG. 17 is a side elevational view similar to that of FIG. 16, showing
intermediate
mooring wiring installed in connection with the suction anchor mooring wire
and showing
subsurface buoys being connected to the intermediate mooring wire and also
showing a surface
buoy, if needed, being connected to the intermediate mooring view;
FIG. 18 is a side elevational view similar to that of FIG. 17 a semi-
submersible drilling
vessel, mobile offshore drilling unit (M.O.D.U.), showing the M.O.D.U. being
moved to a site
where subsurface anchors and mooring wires have been previously deployed and
showing an
anchor handling vessel recovering the surface buoy connected to a rig wire,
utilizing a short
section of chain and also installing a J-chaser stopper device in the mooring
wire system;
CA 02331176 2006-02-23
-4-
FIG. 19 is a side elevational view similar to that of FIG. 18 showing the
anchor handling
vessel winch wire lowering a mooring string utilizing a J-lock chaser device,
with the J-lock
chaser device being stripped back to the M.O.D.U., i.e., rig until free;
FIG. 20 is a side elevational view similar to that of FIG. 19 showing final
connection of
the mooring string to the rig;
FIG. 21 is a front elevational view of a socket connector that is adapted for
connection
to a mooring or heaving line and which is adapted to receive a socket that is
connected to another
line section to thus permit quick and efficient connection and disconnection
of mooring line
sections;
FIG. 22 is a sectional view taken along line 22-22 of FIG. 21 and showing the
internal
geometry of the socket connector as well as the geometry of the connecting eye
thereof;
FIG. 23 is a plan view of the socket connector of FIG. 21;
FIG. 22A through 22F are sectional views taken along respective section lines
22A-22F
of the socket connector of FIG. 22 to thereby show the cross-sectional
configuration of the
connection bail at various locations along the length thereof;
FIG. 24 is a sectional view of a socket element adapted to be fixed to a
mooring line or
mooring connector by zinc or polymer connection and further adapted for seated
assembly within
the wire socket connector of FIGS. 21-23; and
FIG. 25 is a plan view of the socket element of FIG. 24, with undercut and
bottom
surfaces thereof being shown in broken line.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
Referring now to the drawings and first to Fig. 1, the stern deck of an anchor
handling
vessel, also referred to therein to an anchor handling vessel, is shown
generally at 10 and
incorporates a stern roller 12 over which suction anchor piles or mooring
anchors and other
apparatus is launched. The stern of the anchor handling vessel is pitted to
receive 4 suction
anchor piles shown at 14, 16, 18 and 20 which are secured to the anchor
handling vessel by
individual track roller assemblies which are shown in greater detail in Figs.
3-6. The deck of the
vessel is provided with transverse beams or rails 22, 24 and 26, one which
being shown in Fig.
6 at 22. Track roller assemblies are provided as shown in Figs. 3, 4 and 5
with one of the track
CA 02331176 2006-02-23
-5-
roller assemblies, shown generally at 28 in Fig. 3, having parallel track
members 30, 32 and 34
which are interconnected by transverse structural members 36. Roller
assemblies 38 and 39 are
mounted to the outer parallel structural members 30 and 34 and to the
transverse structural
members as is more clearly evident from the end view of Fig. 6. Rollers 50 and
52 are mounted
to the parallel structural members 30 and 34 for rotation and are provided for
contact by parallel
support members 54 and 56 of an anchor cradle 58 to thereby permit linear
movement of the
cradle and the suction anchor pile supported thereby for launching the suction
anchor pile
overboard the stem roller of the vessel. Alternatively, the structural support
members 54 and 56
may comprise elongate supports that are fixed along a side of the suction
anchor pile. The
suction anchor pile 58 is supported directly by the rollers 50 and 52 to
permit its effective
launching and retrieval. Lateral guide members 60 and 62 are welded or
otherwise fixed to the
outer parallel structural members 30 and 34 and function to maintain a proper
relationship of the
support members 54 and 56 to the rollers 50 and 52 as the suction anchor pile
is moved linearly
during its launching or retrieval. Guide members 42 and 42 are disposed in
guiding engagement
with the upper flange 40 of the I-beam 22 and thus permit the track roller
assembly to be moved
laterally relative to the deck of the anchor handling vessel 10 to position a
track roller assembly
for launching an anchor device or for receiving an anchor device during its
recovery. This lateral
positioning movement of the track roller assembly is controlled by at least
one lateral positioning
actuator such as a hydraulic jack assembly 44 shown in Fig. 6. One or more
lift assemblies, such
as the hydraulic lift assemblies 45 and 46, connected to the track roller
assemblies, are positioned
for actuating engagement with the upper surface 48 of the I-beam 22 and are
controllably
energized to lift the roller track assembly and the anchor device supported
thereby sufficiently
to permit the actuator assembly 44 to accomplish lateral movement of the track
roller assembly.
Referring now to Fig. 8 and subsequent figures, the anchor handling vessel 10
is shown
with one of the suction anchor piles 70 located with its lower end at the stem
roller 12 of the
vessel and with its deployment sling 72 being connected by a wire socket
connector shown
generally at 74 to the upper winch wire 76 of the vessel winch system which is
the lifting and
lowering winch 77. The wire socket connector 74 is provided with a connector
element 75, such
as a wire socket element of the type and function shown in Figs. 24 and 25
hereof. Another
winch wire 78 is shown to be connected to a suction anchor pile overboarding
deployment sling
CA 02331176 2006-02-23
-6-
80 that is located intermediate the upper and lower ends of the suction anchor
pile. The suction
anchor pile is shown with its main mooring wire extension 82 secured to a
mooring wire
connector 84 of the suction anchor pile and with its upper end being secured
against one side of
the suction anchor pile by a mooring wire positioning lock 86. At the upper
end of the main
mooring wire extension, there is provided a tapered socket member 88, which
may be of the type
shown in Figs. 12 and 13 thereof. The deployment sling 72 is connected to the
suction anchor
pile 70 by a deployment connector 73 which may be in the form of an elastomer
support to
provide a cushioning capability between the suction anchor pile and the anchor
lifting and
handling or deployment sling 72.
From the position of the suction anchor pile shown in Fig. 8, the suction
anchor pile is
moved over the stern roller 12 until such a time as its weight is supported by
the winch line 76
via the socket connector 74 and the lifting and handling sling 72 as shown in
Fig. 9. Movement
of the suction anchor continues as shown in Fig. 10 until its weight is
largely supported by the
overboarding sling 80 and the support for the anchor begins to transfer from
the winch line 78
to the lifting and lowering or deployment winch line 76 of the lifting and
lowering winch 77.
As shown in Fig. 11, the suction anchor pile is located just under the stem of
the anchor handling
vessel and its weight is supported by the winch line 76 via the socket
connector 74 and the
deployment sling 72. At this point, the winch line 78 is not needed and thus
its overboarding
hook 90 can be disconnected from the overboarding sling 80. A remote operating
vehicle (ROV)
92, shown in Fig. 11, may be utilized to manipulate the overboarding hook and
release it from
the overboarding sling. The ROV is operationally and controllably coupled with
the vessel 10
via a power and service cable 94 under control by personnel of the vessel.
As shown in Fig. 12 the anchor device 70 is lowered to the sea bottom B using
the anchor
handling winch line 76, with the connection between the winch line and the
anchor device being
provided by a releasable connector shown generally at 74. A deployment sling
72 for anchor
handling extends upwardly from the anchor and is connected centrally of the
upper end of the
anchor so that the anchor will be suspended in a desired orientation for
embedment within the
sea bottom B. The deployment sling 72, with its socket connector element 75,
projects upwardly
above the upper end of the anchor device, thus positioning the socket
connector element 75 in
CA 02331176 2006-02-23
-7-
position for being received by a socket body of the connector 74, such as a
socket body of the
type shown in Figs. 21, 22 and 23 hereof.
When the anchor device 70, in this case a suction anchor, reaches the sea
bottom B as
shown in Fig. 13, the anchor device will penetrate the soft silt of the sea
bed by the force of its
weight. Typically in deep water conditions, a ROV 92 is controlled by the
anchor handling
vessel and moves to position its fluid transfer line 96 in assembly with the
fluid transfer
connection 98 of the anchor device 70, as shown in Fig. 14. The ROV 92 will
then be energized
to evacuate water from the interior of the suction anchor device, causing it
to penetrate the sea
bottom to a desired extent as shown in Fig. 14. Alternatively, a remotely
operated connector
having connection and releasing capability may be employed to accomplish
mooring line
connection with or release from an anchor device. With the anchor embedded in
the sea bottom
to its full extent, the lifting and handling r deployment sling 72 will
position the socket connector
element 75 above the sea bottom. At this point the mooring wire extension 82,
which is typically
connected to the side of the anchor device and at a location on the lower
portion of the anchor
as shown in Figs. 14, 15 and 16, will be upstanding along the side of the
anchor device for
positioning the wire socket element 88 thereof above the sea bottom B and at a
location offset
laterally from the deployment sling 72 and its wire socket element 75. Then,
as shown in Figs.
15 and 16, when the winch line 76 is to be used as a section of mooring line,
the ROV 92 can
shift the socket body 77 of the connector 74 from the wire socket element 75
to the wire socket
element 88 of the mooring wire connector or extension 82. In cases where a
separate mooring
line is to be used, the deployment winch line 76 can be recovered to the
anchor handling vessel
and the ROV 92 can be used to establish connection of a connector body 77 of
the mooring
line with the wire socket member 88 of the mooring wire connector or extension
82. Thus, the
anchor device can be installed without any mooring line attached to the
mooring connector or
extension 82 so that the potential for entanglement of the deployment line and
the mooring line
during anchor deployment by a single anchor handling vessel is eliminated.
Only after the anchor
device has been completely installed is the mooring line connected with the
anchor device. The
present invention also facilitates disconnection and reconnection of mooring
lines to anchor
devices, if and when desired, to facilitate efficiency and flexibility of
vessel mooring. After a
mooring line has been connected to the mooring connector of an anchor device,
the mooring line
CA 02331176 2006-02-23
-8-
may be immediately connected to the mooring system of the vessel, if the
vessel is present, or
it may be deployed at the sea bottom in readiness for connection with the
mooring system of the
vessel at a later time.
After the primary mooring wire has been deployed, as shown, with its syntactic
buoy
positioning the terminal end for recovery, the ROV 92 and lowering and heaving
wire 76 with
its lowering hook 90 will be recovered to the anchor handling vessel. After
this has been done,
the anchor handling vessel is loaded with wire and buoys for rig connection
and as shown in Fig.
22, the ROV 92 functions to connect the hoisting and lowering wire 76 with its
hook 90 to a
connector of the mooring line as shown in Fig. 18. From the condition shown in
Fig. 18, the
primary mooring wire section which can be the deployed anchor handling line
76, is hoisted to
the anchor handling vessel and is pulled over the stern roller of the vessel
as shown. With the
terminal end of the primary mooring wire located on the anchor handling
vessel, an intermediate
section 116 of mooring wire is connected to the primary mooring wire section
by a connector 114
as shown in Fig. 24. The intermediate mooring wire section 116 is then
provided with one or
more buoys as shown at 118 and 120 for supporting the intermediate mooring
wire 116 and for
providing the completed mooring line assembly with buoyant support
intermediate its length.
After the buoys 118 and 120 have been attached to the intermediate mooring
wire 116, as shown
in Figs. 17 and 18, a winch line of the anchor handling vessel, which is
connected to the
intermediate mooring wire 116 above the uppermost buoy 118, will be paid out
from the anchor
handling vessel to thus allow the vessel to back into the rig to receive the
mooring wire 124 of
the rig. The mooring wire of the rig will be paid out from its winch so that,
after its connection
to the intermediate mooring wire 116, the mooring wire installation from the
rig to the suction
anchor pile can be controlled by the on-board winch of the rig. At this point
of the mooring
operation, as shown in Figs. 18 and 19, the upper winch wire 122 of the anchor
handling vessel
is heaved to a position adjacent the stern of the vessel to expose the mooring
wire connection.
The rig mooring wire 124 is then connected to the intermediate mooring wire
section 116 at a
connector 126 that is located immediately above the upper buoy 118 of the
intermediate mooring
wire, as shown in Fig. 18. The mooring wire 124 installation is completed by
lowering the rig
mooring wire 116 and the intermediate mooring wire with its buoys by a winch
line 126 having
a J-chaser 128 connected thereto as shown in Fig. 19. When the mooring wire
installation
CA 02331176 2006-02-23
-9-
reaches its proper catenary, the J-chaser will simply become unhooked from the
mooring wire
and may then be recovered to the vessel. The mooring wire winch system of the
vessel will then
adjust the mooring wire assembly as is proper for stationing of the rig at its
proper location
relative to the sea floor B.
When it is appropriate to disconnect the rig from its mooring wire
installation, the anchor
handling vessel 10 will position its heaving wire with the J-chaser 128 in
contact with the
mooring wire 124 of the rig. The anchor handling vessel will then move away
from the rig,
thereby causing the J-chaser 128 to move along the rig mooring wire 124 until
it comes into
contact with a short chain located immediately above the upper buoy 118 of the
intermediate
mooring wire section. After this has been done, the heaving line and J-chaser
is heaved to a
position exposing the short recovery chain above the upper buoy 118 and thus
also exposing the
connection between the rig mooring wire 124 and the intermediate mooring wire
116. The rig
mooring wire 124 is then disconnected from the intermediate mooring wire 116
at the vessel deck
and is recovered to the rig by the rig winch system as shown in Fig. 31. It
should be borne in
mind that the connector 126 for making the connection of the rig mooring wire
124 with the
intermediate mooring wire, may be in the form of a quick release type socket
connector which
is explained in detail hereinbelow in connection with Figs. 21-25. In fact,
each of the connectors
along the length of the mooring wire installation may be defined by wire
socket connectors, if
desired, or may take the form of any other suitable mooring wire connector
without departing
from the spirit and scope of the present invention. After the rig mooring wire
has been
disconnected and recovered the anchor handling vessel will lower a subsea
retrieval tool to a
depth below the lower buoy 120 shown in Figs. 18 and 19 and will then connect
the subsea
retrieval tool to the intermediate mooring wire 116 below the buoys. The ROV
92 can be
utilized for this purpose. The subsea retrieval tool is then heaved to the
deck of the vessel
thereby causing the buoys 118 and 120 to be decked without damage because the
weight of the
intermediate mooring wire 116 will not be present on the buoys are as they are
heaved over the
stern roller of the anchor handling vessel. After the buoys have been secured
on deck, the
intermediate mooring wire section 116 is then recovered by the anchor handling
vessel. After
the intermediate mooring wire section has been recovered to the anchor
handling vessel, as shown
in Fig. 18, so that the mooring line connector 114 is located on the deck of
the vessel, the
CA 02331176 2006-02-23
-10-
connector 114 will be disconnected and the vessel crew will reinstall a
conventional syntactic
foam buoy with a deployment/recovery sling (not shown) and begin to deploy the
primary
mooring wire section 76 to the ocean bottom. The syntactic foam buoy,
connected to the primary
mooring wire section, the primary mooring line is then lowered to the sea
floor B by the winch
wire 78 and deployment and recovery hook 90. The ROV 92 is deployed from the
anchor
handling vessel 10 and is used to disconnect the deployment recovery hook 90
of the winch wire
from the sling above the syntactic buoy. After the hook 90 has been
disconnected from the sling,
the winch wire 78 and deployment/recovery hook 90 are then recovered to the
anchor handling
vessel, leaving the primary mooring wire 76 lying on the sea floor with its
terminal end being
positioned above the ocean bottom by the syntactic buoy so that its sling will
be positioned for
immediate reconnection to the intermediate mooring wire section 116 as needed.
After this has
been done, the anchor handling vessel can then proceed to the rig as shown in
Figs. 18 and 19
to repeat the suction anchor pile and mooring line installation for another
one of the plurality of
suction anchor pile and mooring line assemblies of the rig mooring system.
It may be appropriate at some point to recover the suction anchor pile 70 so
that it may
be reinstalled at some other location as may be desired for different
stationing of the rig relative
to the sea floor B. This is accomplished by connecting a vessel winch line to
the heaving sling
of the primary mooring wire 76 and heaving the primary mooring wire onto the
anchor handling
vessel until it is oriented substantially vertically above the suction anchor
pile 70. With the
primary mooring wire so positioned, the ROV 92 is then utilized to essentially
pivot the mooring
wire connector extension 82 about its connection 84 with the pile so that it
enters an entrapment
slot 83 of the suction anchor pile. The ROV will then manipulate a lock on the
suction anchor
pile to secure the mooring wire extension 82 within the entrapment slot 83, so
that the mooring
line extension is retracted and latched at its substantially vertical
orientation. After this has been
accomplished, the ROV 92 will be moved to the subsea connector 74 as shown in
Fig. 41 and
will disconnect the connector from the mooring wire connector extension 82.
Since the mooring
wire connector extension 82 will be locked within the entrapment slot of the
suction anchor pile,
it will remain substantially vertically oriented with its socket element 88
positioned for
subsequent reconnection to a mooring wire section in simple and efficient
manner. The ROV
will then move the subsea connector 74 from the socket 88 of the mooring wire
extension 82 to
CA 02331176 2006-02-23
-11-
the anchor lift sling 72 in preparation for lifting the suction anchor pile to
the deck of the anchor
handling vessel. Then, the ROV 92 will be maneuvered for connection of its
fluid transfer line
96 with the fluid transfer connection 98 of the suction anchor pile. The pumps
on the vessel are
then energized, forcing water through the connection 98 into the suction
anchor pile and thus
developing a differential pressure induced force that moves the suction anchor
pile upwardly.
Simultaneously, a heaving force is applied to the winch wire 76 of the vessel,
which, through the
wire socket connector 74, lifts the suction anchor pile from its embedded
relation within the sea
floor B until the suction anchor pile is located within the 15' silt line of
the sea floor B. At this
point, the ROV will disengage its fluid transfer conduit 96 from the suction
anchor pile coupling
98. After the ROV has been disconnected, the suction anchor pile is heaved
upwardly by the
winch line 78 until the suction anchor pile is located at a predetermined
depth, i.e. about 60'
below the anchor handing vessel. With the suction anchor pile 70 stationary
below the stem of
the vessel as shown in Fig. 11, the ROV 92 will be utilized to connect a
recovery hook 90 of a
recovery winch line 76 or 78 as the case may be to the deployment/recovery
sling 80 of the
suction anchor pile. The recovery winch line 76 or 78 is then heaved moving
the suction anchor
pile upwardly toward the stem of the vessel and causing the
deployment/recovery wire 76 to
become slack. Heaving is continued, causing the deployment/recovery sling 80
to pass over the
stern roller 12 of the vessel and thus initiating boarding movement of the
suction anchor pile over
the stem roller as shown. To then assist in maneuvering the suction anchor
pile so that it can
be decked by a heaving force applied by the winch system to the wire 76 or 78,
the vessel is
moved forwardly in the water, with the anchor pile positioned as shown in Fig.
10, thus applying
a water drag induced force against the lower portion of the suction anchor
pile to assist in its
pivot-like movement about the stem roller 12. The winch wire 78 will continue
movement of
the suction anchor pile until it is slowly brought aboard the vessel and is
allowed to rest in a
cradle that is positioned by the moveable track system that is mounted on the
deck of the vessel.
The subsea connector shown generally at 74 in the various figures described
above, may
conveniently take the form of a wire socket connector, which is shown in Figs.
21-25 which
incorporates a basket structure defining a tapered internal seat receptacle
for receiving the tapered
wire socket of a wire line or other type of connector device and having a slot
through which a
winch line, mooring line or mooring connector is laterally movable. The
connector 74
CA 02331176 2006-02-23
-12-
incorporates a wire socket body structure 140 of generally circular cross-
sectional configuration
having spaced, generally parallel surfaces 142 and 144 which define a wire or
connector access
opening 146. The generally parallel surfaces 142 and 144 are disposed in
generally parallel
relation with the longitudinal axis 145 as shown in Fig. 21. A bail structure
shown generally at
148 is formed integrally with the wire socket body structure 140 and defines
upwardly extending
body support arms 150 and 152 that are interconnected at the upper ends
thereof by a curved bail
section 154 of circular cross-sectional configuration as shown in Fig. 22. The
cross-sectional
geometry along the length of the connector body support arms 150 and 152 is
indicated by
sections 22A-22A thorugh 22F-22F as shown in Fig. 22 and in Figs. 22A-22F.
The connector body structure 140 defines a central socket receptacle opening
156 which
is in communication with the wire access opening 146. About the central
opening 156 the
connector body 140 also defines a reverse angled circular seat shoulder 158
which extends to the
wire access opening 146. The conical, reverse angled seat shoulder 158
provides for seating of
a wire socket element, such as shown in Figs. 24 and 25, within the connector
body as will be
discussed below. The connector body structure also defines a pair of locking
tabs 160 and 162
which project downwardly on each side of the wire access opening 146 as is
best shown in Figs.
21-23. These locking tabs define registering through bores 164 and 166 that
can receive a bolt,
pin or other suitable locking connector for securing a winch line or other
force transmitting line,
as the case may be, within the central socket receptacle opening 156 of the
connector body. The
bolt or locking pin may be extended through the registering through bores 164
and 166 by
manual operation orby a robot or remote operating vehicle (ROV) in order to
present inadvertent
disassembly of the wire socket connection assembly in the event the wire line
should become
slack for any reason.
As shown in Figs. 24 and 25 a socket member shown generally at 170 is defined
by a
socket body 172 having a tapered central passage 174 through which a wire line
or mooring line
extends. The socket body is permanently fixed to the wire line by zinc,
cadmium, polymer or
any other material that is poured into the through passage and about the wire
line in its molten
or uncured liquid state and is then allowed to harden or cure to permanently
fix the socket
member 170 to the wire line. The socket body also defines a circular conical
shoulder 172
having the same angle as the reverse angled conical seat shoulder 158 of the
socket body 140.
CA 02331176 2006-02-23
-13-
After the wire line has passed laterally through the wire access opening 146,
and has
located the socket body above or in registry with the central opening 154 of
the socket connector
body 140, the wire line is lowered in relation to the connector body structure
140 causing a
tapered external guide surface 178 of the socket body 172 to guide the socket
member 170 into
the socket receptacle opening 154, thus causing the conical shoulder 176 of
the socket body to
seat against the conical shoulder 158 of the connector body structure 140. As
linear force is then
applied to the wire line, the socket member 170 will be restrained by its
seated relation within
the socket receptacle of the connector body 140 and the reverse angled conical
surfaces 158 and
176 will interact to minimize potential spreading of the connector body by the
wire socket
member, thus enabling the connector to withstand significant forces such as
are encountered
during mooring of M.O.D.U.'s and other marine vessels. When connector
disconnect is desired
the wire socket 170 will become unseated from its supported relation within
the wire socket
receptacle opening 154 of the connector body 140 simply by its upward or
linear movement
relative to the connector body structure, depending upon its orientation.
After being unseated in
this manner, assuming a locking member is not present within the registering
openings 164 and
166, the wire line and wire socket are moved laterally relative to the
connector body structure
140 thereby causing the wire to exit laterally from the receptacle opening via
the wire access
opending 146. It should be borne in mind that the wire socket connector shown
in Figs. 21-25
may be of other configuration as desired, it being appropriate only that it
have the capability of
being quickly assembled and disassembled particularly in a remote environment
such as the
subsea environment and perhaps with the use of a ROV or other actuating
mechanism for
controlling relative movement of the connector body and wire socket structures
for accomplishing
quick and simplified connection or disconnection thereof.
When force is applied by urging the socket connector relative to the wire
socket, which
occurs as lifting or mooring force is applied to the socket connector of Figs.
21-25, the mating
tapered reverse angled shoulder surfaces 158 and176 of the wire socket body
and wire socket
develop a resultant force which is directed radially inwardly rather than
radially outwardly as is
typical of conventional wire socket connectors. When conventional tapered wire
socket
connectors are employed, application of seating force of the wire socket
within the connector
body places the body structure under hoop stress. When the hoop stress is of
high magnitude,
CA 02331176 2006-02-23
-14-
the conventional connector body structure can become radially yielded to the
point that it may
split. According to the principles of the present invention, the inwardly
directed resultant force
developed by the mating reverse angled shoulder surfaces 158 and 176 under
load, minimizes the
potential for hoop stress induced yielding or splitting of the socket body and
thus enhances the
load carrying characteristics of the wire socket connector mechanism of the
present invention.
In accordance with the preferred method of deployment of the preferred
embodiment, the
suction anchors will be deployed in the manner set forth above in connection
with Figs. 8-15.
No mooring wires will be installed. The anchor handling vessel may return at a
later time with
mooring wires and accomplish installation of all of the main mooring wires of
the stationing
system. If needed, sub-surface marker buoys can be inserted into the mooring
string to relieve
the weight of the interconnected mooring components. Once all mooring
components have been
installed, a surface suspension/market buoy 123 is installed as shown in Fig.
17.
The mobile offshore drilling unit, "rig" 139 is then moved to the stationing
site or location
as shown in Fig. 20. The surface buoys are recovered and the mooring wires are
attached to the
rig mooring wires 76 and 116 which are connected to the mooring wire handling
system of the
rig, with short sections of chain 121 inserted between the predeployed mooring
wires 76 and 116
and the rig mooring wires 124. A J-chaser stopper device 128 is then installed
in each mooring
string by connecting the J-chaser stopper device to the short section of
deploy/recover chain. The
J-chaser stopper device 128, as shown in Fig. 20, has a body structure 130
defining a first stopper
connector 132 for connection to the mooring line 116, typically above the
buoys 118 and 120,
and a second stopper connector 134 for connection to the short length of
deployment/recovery
chain 121. The chain 121 is connected to the mooring line 124 of the buoyant
marine structure,
MODU or rig 139. From the body structure 130 a pair of hook-like projections
136 and 138
extend laterally to provide for catching the J-chaser in the event it should
pass over the chain 121
without becoming mechanically engaged with one of the links of the chain.
The connected mooring string is lowered beneath the surface with a J-Chain
Chaser
(Locking Style). Once the mobile offshore drilling unit has accepted the
weight of the mooring
string, the J-Chain Chaser is forced by the anchor handling vessel to slide
along the rig mooring
wire until it is free. This mooring line attachment is now complete and is in
the form shown in
Fig. 20.
CA 02331176 2006-02-23
-15-
The preferred embodiment of the present invention is shown pictorially in
Figs. 17-20.
In Fig. 17 the mooring wire is shown to be extended from an installed suction
anchor and with
a quick-disconnect connector device 114 interconnecting an intermediate
mooring line with the
main mooring line. After the intermediate mooring wire 116 has been installed,
as shown in Fig.
17, at least one and preferably a plurality of syntactic buoys 120 are
connected to the intermediate
mooring line to thus provide for its positioning below the sea surface S but
in position for
efficient recovery when disconnected from the mooring line of the mobile
offshore drilling unit
or other vessel shown generally at 11. If desired, a surface buoy 123 may be
installed at the
upper end of the intermediate mooring line 116 so as to provide means for
simple and efficient
location of the mooring line.
When the mobile offshore drilling unit, M.O.D.U. 11, has been moved to the
mooring site
or location, it is then necessary to connect the preinstalled moorings. The
anchor handling vessel
then recovers the surface buoy and connects to the rig mooring wire as shown
in Figs. 18 and
19, using a short section, 25' or so, of mooring chain 121. At this time the
anchor handling
vessel then installs a J-chaser stopper device 128 in the mooring string, the
JChaser Stopper being
connected to the mooring line of the rig by the short section of chain 121. As
shown in Fig. 19,
the anchor handling vessel winch wire is utilized to lower the mooring string,
utilizing a J-lock
chaser. The J-lock chaser is then stripped back to the drilling vessel until
free of the mooring
wire. Fig. 20 illustrates the final mooring connection between the suction
anchor and the drilling
vessel. A plurality of mooring strings such as is shown in Fig. 20, typically
eight, are utilized
to properly station the mobile offshore drilling unit.
In view of the foregoing it is evident that the present invention is one well
adapted to
attain all of the objects and features hereinabove set forth, together with
other objects and features
which are inherent in the apparatus disclosed herein.
As will be readily apparent in those skilled in the art, the present invention
may easily be
produced in other specific forms without departing from its spirit or
essential characteristics. The
present embodiment is, therefore, to be considered as merely illustrative and
not restrictive, the
scope of the invention being indicated by the claims of an issued patent based
hereon rather than
the foregoing description, and all changes which come within the meaning and
range of
equivalence of such claims are therefore intented to be embraced therein.
