Note: Descriptions are shown in the official language in which they were submitted.
~26~L~5~
MULTI-REEL OPERATIONAL LINES ~AYING VESSEL
BACKGROUND OF THE INVEI~TION
1. FIELD OF THE INVENTION
This invention relates to a reel pipe laying
vessel on which a plurality of reels are disposed for
laying multiple operational lines in waters having depths
limited only by the strength of the pipe. More
particularly, the invention pertains to a new type of
vessel in which at least two reels are employed, one or
more of which is used for storing and unspooling a rigid
walled pipeline. The multiple reels can be used for
laying a variety of lines in association with one or more
rigid walled pipelines. The vessel includes a layout
system which provides for simultaneous layout of multiple
o~erational lines.
The vessel of this invention is designed to
accommodate a permanently mounted pipe spooling main reel
which is of substantial size and is capable of spooling
pipe up to 16 inches diameter.
2. HI STORY OF ThE PRIOR ART
In laying offshore subsea pipelines for such uses
as the gathering of oil and/or gas from offshore wells,
as, for example, in the Gulf of Mexico, it has been
con~7entional to use one of two main methods to lay the
pipe. In the first, called the "stovepiping" method, a
pipeline is fabricated on the deck of a lay barge by
welding together individual lengths of pipe as the pipe is
paid out from the barge. Each length of pipe is about 40'
or 80' long. Thus, the pay-out operation must be
interrupted periodically to permit new lengths of pipe to
be welded to the string. The stovepiping method requires
that skilled welders and their relatively bulky equipment
accompany the pipelaying barge crew during the entire
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layout operation; all weldin~ must be carried ou~ on site
and often under adverse weather conditions. Further, the
stovepiping method is relatively slow, with experienced
- crews being able to lay only one to two miles of pipe a
S day. This makes the entire operation subject to weather
~ conditions which can cause substantial delays and make
working conditions quite harsh.
The other principal conventional method is the
reel pipelayiny techni~ue, in this metilod, a pipeline is
wound on the hub of a reel mounted on the deck of a lay
barge. Pipe is generally spooled onto the reel at a shore
base. At such a shore base, short lengths of pipe can be
welded under protected and controlled conditions to form a
continuous pipeline which is spooled onto the reel. The
lay barge is then towed to an off-shore pipelayiny
location and the pipeline is spooled off the reel between
completion points. This method has a number of advantages
over the stovepiping method, among them, speed (one to two
miles per hour);-lower operating costs (e.g., smaller
welding crews and less welding equipment must be carried
on the lay barge); and less weather dependency.
The broad concept of reel pipelaying was also - \
disclosed in British Pat. No. 601,103 ~Ellis), issued
Apr. 28, 1948, wherein it was suggested that lengths of
pipe be joined together at the manufacturing plant and
; coiled onto a drum, mounted on a ~arge or ship; the loaded
barge would then be moved to the desired marine location
and the pipe unwound from the drum by fixing one end of
the pipe and towiny the barge away from the fixed location.
After a hiatus of about thirteen years, research
into the reel pipelaying technique was renewed and was
carried on by Gurlter, ~ebert & Co., Inc. of New Orleans,
Louisiana. By 1961, that company had sufficiently
advanced the reel pipelaying technique to make it a
commercially acceptable and viable method laying pipe in
the offshore petroleum industry, able to compete with the
`` ~26~56
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traditional stovepiping technique. The first known
commercial pipelaying reel barge, called the U-303, was
built by Aquatic Contractors and Engineers, Inc., a
subsidiary of Gurlter, ~ebert, in 1961. The U-303
utilized a large vertical axis reel, ~ermanently mounted
on a barge and having horizontally oriented flanges
(generally referred to in the trade as a "horizontal
reel"). A combined straightener-level winder was employed
for spooling pipe onto the reel and for straightening pipe
as it was unspooled. The U-303 first laid pipe
commercially in Sept. 1961, in the Gulf of Mexico off the
coast of Louisiana and was used successfully during the
1960's to lay several million linear feet of pipe of up to
6" diameter. The U-303 reel pipelaying barge is described
in U.S. Pat. No. 3,237,438 (Tesson) and U.S. Pat. No.
3,372,461 (Tesson) both assigned to the assignee of the
invention hereof.
The successor to the U-303, currently in use in
the Gulf of Mexico and known in the trade as the
"Chickasaw" also utilizes a large horizontal reel,
permanently mounted to the barge such that it is not
readily movable from one carrier vessel to another.
Various aspects of "Chickasaw" are described in the
following U.S. Patents, all assigned to the assignee of
the invention hereof:
Sugasti, et al. - U.S. Pat. No. 3,630,461
Gibson - U.S. Pat. No. 3,651,778
Mott, et al. - U.S. Pat. No. 3,680,342
Key, et al. - U.S. Pat. No. 3,712,100
The Gibson patent shows an apparatus for
diverting a single pipeline from a horizontal unspooliny
direction to a vertical direction for layout in a body of
water. While the patent mentions that more than one reel
could be employ~d there is no enabling disclosure from
which a multiple reel vessel could be constructed and
operated.
.
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U~S. Patent No. 3,685,306 to Mott also describes
an apparatus which diverts a single pipeline from a
horizontal position to a vertical direction. The pipeline
can be successively unreeled from adjacent ganged reels.
Commercial reel pipelaying techni~ues require the
use of certain pipe handling equipment in addition to the
reel. Among such pipe handling e~uipment usually employed
in a commercial reel pipelaying systems is a straightener
mechanism. This may take the form of a series of rollers
or tracks, or any other arrangement which imparts
sufficient reverse bending force to the pipe to remove
residual curvature so that after unspooling, the plpe will
lay substantially straight on the sea bottom.
U.S~ Pat. No. Re 30,846 (Lang et al) describes an
apparatus for laying pipe from a vertical reel in which
the pipe conditioning apparatus is pivotable to adjust the
lift-off angle of the pipe relative to the norizontal
(e.g., the deck of a ship) as a function of the water
depth in which the pipe is being laid. This has distinct
commercial advantages, especially where the reel
pipelaying system is incorporated into a self-propelled
ship, such as that of the present invention, capable of -
traveling to dif~erent job sites, having different ~ipe
size and/or lay depth requirements.
An early concept for a reel pipelaying ship is
described in Goren, et al., "The Reel Pipelay Ship - A New
Concept" Offshore Technology Conference Proceedings, May
1975 (Paper No. - OTC 2~00). This paper (hereafter the
Goren, et al 1975 OTC Paper) describes advantages and
operating features of a proposed reel pipelaying ship.
However, the cost of construction of a ship as described
there was estimated to be on the order of $1,000,000,000.
Apache Reel Laying Vessel
The research and development work for the ship
described in the Goren, et al paper, (done at great
expense on behalf of the assignee of this application) was
,,, '.'1...'. ~ ' ' ''' ~ ' , ,,
.~
S6
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subsequently materially revised in numerous major
respects, and substantial changes and improvements were
made to achieve the design of a substantially different
reel pipelaying ship wnich is described in the following
I~.S. Patents, all assigned to the assignee of the
invention hereof:
Springett, et al. - U.S. Pat. ~o. 4,230,421
Uyeda, et al. - U.S. Pat. No9 4,269,540
Yenzer, et al. - U.S. Pat. No. 4,297,054
Springett, et al. - U.S. Pat. ~7O. 4,340,322
Uyeda, et al. - U.S. Pat. No. 4,345,855
The disclosures of these five single reel patents are
hereby incorporated as though fully set forth herein.
The vessel described in these patents was
constructed and is currently in use in various offshore
oil fields and is known in the offshore oil industry as
the "Apache". This vessel is a self-propelled dynamically
positioned single reel pipelaying ship which has a
specially constructed hull comprising a reel support
structure for rotatably mounting a vertical ree] for
unspooling a rigid walled pipeline. Only a single
pipeline is handled by this ship. Other pipe handling
equipment includes a pipe bending radius controller; pipe
straightening equipment; clamping assembly; a stern pipe
guide assembly and a level wind assembly. A tensioning
assembly is also arranged on a support ramp assembly. The
pipe exit angle or the water entry angle is from 18 to
about 60 since this is the range of angular movement of
the support ramp assembly. The upper part of this range
of the pipe water entry angles is sufficient to
accommodate laying a single pipeline in approximately
3,000 ft. water depth. In order to lay pipe at greater
depths it is necessary to increase the pipe water entry
angle.
The Apache vessel is not equipped to layout
multiple lines since it has but a single main reel and
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does not have adequate unused deck space to permit the
convenient placement of auxillary reels. An early
suggestion which was made during the vessels construction
phase and mentioned in the above patents, was that
portable reels could be placed on the Apache deck to
permit stern bundling of smaller lines with the pipeline
from the main reel. These smaller lines were not required
to be passed through the pipe handling equipment with the
main reel pipeline according to the suggestion and there
were no operative disclosures as to forming a juxtaposed
plurality of operational lines by contact with a laying
device which is adapted to move all the lines at a common
velocity. This stern bundling suggestion was made in tile
OTC Paper No. 3069, May 8-11, 1978.
3. SUM2~RY OF TH~ INVENTION
There are increasing requirements in the offshore
petroleum industry for laying multiple operational lines
in deep water at depths greater than 3,000 ft. and in
remote areas far from supply bases~ To be commercially
viable a pipelaying vessel must also be capable of laying
either single or multiple operational lines in shallow
waters of less than 200 ft. up to 3,000 ft. depth. The
multi-reel pipelaying vessel of this invention represents
a new and different concept to meeting these needs.
The vessel utilized for this invention can be a
self-propelled dynamically positioned ship or it can be a
barge which requires a tug for motive power. The vessel
deck is utilized to mount auxiliary reels f-or the layout
of additional operational lines simultaneously with a
layout of at least one rigid walled pipeline from the main
reel. At least one additional reel is necessary for this
purpose.
A principal feature of the present multi-reel
pipelaying vessel is that an operational lines laying
device is mounted adjacent to the stern of tne vessel.
plurality of operational lines are unspooled from the
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reels mounted on the vessel and are laid~out into
simultaneous contact with the laying device which includes
an operational lines supporting means adapte-d for
providing moving contact with the operational lines. The
preferred laying device of the present invention changes
the direction of movement of the plurality of operational
lines from horizontal to vertical and can be used for
laying operational lines in shallow waters of under 200
ft. down to much greater depths of 7,500 ft and beyond.
The supporting means is adapted for gathering the
operational lines into an initial juxtaposed configuration
which is parallel with the direction of forward vessel
motion. ~11 of the operational lines are moved at the
same linear velocity due to the contact thereof with the
supporting means of the operational lines laying device.
The preferred operational lines laying device also
includes straightening and tensioning devices which are
adapted to straighten and provide tension for the
operational lines while maintaining the same in a
juxtaposed array which is aligned with the direction of
forw~rd vessel motion. The straightening means is adapted
for imparting a reverse bending force to the rigid walle~
pipeline(s) which are among the operational lines being
laid out.
The preferred operational lines laying device has
a pipe take-off assembly mounted adjacent to the stern of
the vessel. The take-off assembly includes a rotatably
mounted drum and a pipe take-off structure which can
preferably contain straightening and tensioning devices as
well as additional pipe clamping means when required. The
pipe take-off drum in the operational lines laying device
is not powered by a separate motive means but rather is
rotated dependent upon frictional contact between the
operational lines with the periphery of the drum which
provides the operational lines supporting means. The
take-off structure is rotatably journaled for permittiny
i6
water entry angles of from about 20 to about 90 for the
operational lines array to lay out lines from 200 ft. to
greater depths. The upper part of this range from about
60 to about 90 is used for deep water laying in 3,000
ft. and greater depths.
Level wind carriages are also preferably provided
for the operational lines laying device and the auxillary
reels. -
The operational lines laying device can be
arranged to cooperate with a straightening devicecontained within the pipe take-off structure so as to
contribute one of three force imposition zones on the
rigid walled pipeline(s) in order to reverse bend the
rigid walled pipeline opposite the curvature imparted by
the storage reel. In deep waters beyond 3,000 ft. the
weight of the pipeline(s) is sufficient to elastically
straighten the riyid walled pipe. In this embodiment it
is possible to use the hydraulic braking systems on the
operational lines reel motors to provide tensioning of the
lines, thus permitting pipe layout in the absence of
separate straightening and/or tensioning devices. The
laying device and the operational lines storage reels
together with the associated straightening and tensioning
devices and level wind carriages form an operational lines
array layout system which has various novel features.
The preferred embodiment has the advantage of
being lightweight, about 270 long tons, compared to about
600 tons for the pipehandling equipment on the aft deck of
the Apache pipelaying vessel.
Other embodiments of the layiny device employ
multiple track straightening and tensioning assemblies
mounted on carriages which are pivotally attached to the
vessel or which are operated in a fixed plane with respect
to the vessel deck. In these embodiments the carria~es
for the multiple track assemblies are mounted for level
winding transverse motion with respect to the vessel's
longitudinal center line.
`~6~ 5~i
~ dditional embodiments employing multiple track
straightening and tensioning assemblies as the pipeline
laying devices are used for laying out o~erational lines
arrays in shallow water of less than 200 ft. up to depths
of about 3,000 ft-. In the first of these embodiments the
multiple track assemblies are contained in a carriage
which is pivotally attached to the vessel so that a range
of pipeline entry angles of from about 20 to about 60
can be employed. In another of these other embodiments
the multiple track carriage is operating in a fixed
angular plane with respect to the vessel deck for the
layout of multiple operational lines in shallow waters of
up to about l,500 ft. Two modifications of this
embodiment are described herein.
In summary, the preferred embodiment includes a
laying device comprising a rotatably mounted drum and an
attached pipe take-off structure which is operative for
laying out operational lines arrays including at least one
rigid walled pipeline over a very wide range of water
depths of from less than 200 ft. to much greater depths
even beyond 7,500 ft. The embodiment having multiple
track straightening and tensioning assemblies mounted on_a
pivotal ramp is capable of operational lines layout in an
intermediate depth of water up to about 3,000 ft. and the
embodiment having the multiple track assemblies mounted on
carriages operating in fixed planes is useable for shallow
water depths up to about 1,500 ft.
Straightener and Tensioner Devices
In each of the first two embodiments summarized
above, the straightening and tensioning devices can be of
two types. The first type is a straighteniny device which
is operated independently from the tensioning device. The
second type is a combined straightening/tensioning device
comprising two multiple track assemblies which are
employed on opposite sides of the operational lines array
in order to provide both of the straighteniny and
56
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tensioniny functions. The second typé involves the use of
a new straiyhtening/tensioning device which is capable of
imparting controlled curvature to the rigid walled
pipeline(s) within the operational lines array and is also
cap~ble of providing longitudinal tension force. The
advantage of the second type is that only two such
assemblies are required for both of the straiyhtening and
tensioning functions whereas in the first type four or
five separate of the track assemblies are required for the
layout of even a single rigid walled pipeline.
In the third embodiment, wherein carriages
operating in fixed planes above the deck are used, the
combined straightening/tensioning device is preferred
although the first type of independent straightening and
tensioning devices can be employed with long ramps.
In each of the above described embodiments the
operational lines laying device is mounted on the vessel
via a carriage which is capable of level winding
transversely across the vessel deck to provide for
controlled spooling and unspooling of the pipelines array
on to and off a plurality of storage reels. The storage
reels are fitted with hydraulic motors for imparting
motive power to the reel flanges or rims in order to
provide for spooling up of the lines. The hydraulic
motors are also fitted with hydraulic braking systems for
controlling tension of the lines during unspooling and to
control the rate of line(s) layout.
~ ach of the embodiments of the present invention
permits a plurality of operational lines including one or
more rigid walled pipelines to be laid out in an array on
the bottom of bodies of water in a controlled manner. The
particular embodiment selected for a given project depends
upon the depth of water and the project budget available.
Other techriical/economic considerations such as the
permissible capital investment, speed of pipeline layout,
customer flexibility of design characteristics, and sea
9~6~156
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.
state spectrum also enter into the selection process.
Within the six embodiments of this invention the full
range of layiny conditions are ~roviding for the-three
main embodiments of the operational lines laying vessel
cover a wide range of layout depths, whereas the use of
specific straightening and tensioning devices used is
determined by various pipe handling technical
characteristics and economic considerations.
Another feature of the present invention is tnat
a dynamically positioned vessel can be alternately
converted between a single pipeline laying capability such
as described in the above mentioned Springett, et al.,
Uyeda, et al. and Yenzer, et al. patents which is embodied
in the Apache pipelaying ship and the vessel described in
the present application. In order to accomplish this
alternate use, the main pipeline reel is maintained in its
fixed position and the remainder of the pipe handling
equipment shown on the aft deck of the vessel in those
U.S. patents is replaced with the layout system herein
described which includes one or two auxiliary reels and
the operational lines laying devices described herein. -
Thus, a convertible feature for operation of a pipe layi~g
vessel between a single reel vessel and a multi-reel
vessel is also included within the present invention.
- It is, therefore, an object of the present
invention to provide a multi-reel pipelaying vessel which
can simultaneously layout two or more operational lines
onto the sea bottom of wherein at least one of the lines
is a rigid walled pipeline.
Another object is to provide a pipelaying vessel
wherein an array of multiple operational lines is laid out
from a common laying device which equalizes the layout
velocity of the operational lines array.
Yet another object is to provide an operational
lines array layout system for use on a vessel in wilich one
or more storage reels are provided for spooling and
~LZ6~ lS6
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unspooling of a plurality of riyid walled pipeline~. T~lis
system includes the use of a common laying d~vice-through
which the array passes.
Another object of the present invention is to
5- provide a layout system in which three storage reels a~e
mounted on a vessel deck for spooling and unspooling an
array of multiple operational lines for layout onto the
sea bottom after passing through a common laying device
which provide.s for equalizing the layout velocity of the
lines.
Yet another object of the present invention is to
provide a layout system which is of lightweight and can be
transferred on to pipelaying vessels by exchange of
pipehandling equipment preexisting on such vessels with
the layout system herein described.
Another object is to provide an improved
straightener/tensioner device which permits the
establishment of selected curvatures for controlling the
straightening process and applying the desired tension for
maintaining pipeline profile over a wide range of layout
water depths.
Another object is to provide an improved spooli~g
and unspooling method for use with the operational lines
array layout system herein described.
For convenience, the following terms may be
employed in the description of this invention:
1. A "turn" is that length of pipe wound through one
complete revolution of the reel.
2. A "wrap" comprises a plurality of turns making up
a layer of pipe wound on the reel across the full
or substantially full width of the reel.
3. "Level winding" refers to the transverse movement
of the operational lines layiny device or a
storage reel across the deck of the vessel. The
"level winding means" refers to apparatus for
carrying out such movement.
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4, "Multiple track straightening OL- tensioning
assemblies" refers to flexible track systems
- having a plurality of pipe support pads mounted
thereon and which are designed for either of the
two functions of straightening or tensioning.
5. The term "multiple-track straightening/tensioning
assemblies" refers to tensioning assemblies which
are desiyned to provide both straightening and
tensioniny functions in a single pair of such
assemblies when positioned on opposite sides of
the operational lines array.
6. "Carriage" refers to the support frame structure
which is used to-mount the operatioIIal lines
laying device(s) on the vessel and to provide for
level winding thereof.
7. "Main reel" refers to a large diameter storage
reel which is permanently mounted within the
vessel for spooling and unspooling rigid walled
pipeline.
8. The notations "s" for starboard, "p" for port,
"f" for fore, and "a" for aft have been used for
convenience in numerals designati-ons.
Other features and advantages of the multi-reel vessel of
this invention will become apparent from the following
detailed description of a preferred embodiment.
BE~IEF DESCRIPTION OF THE D~AWINGS
Figure 1 is a starboard side elevation general
arrangement view of a preferred embodiment of the
multi-reel vessel;
F~gure 2 is a top plan view of the multi-reel
vessel of Figure l;
Figure 3 is a schematic side elevation
cross-section of a fixst embodiment of the pipe take-off
structure of the present invention;
Figure 4 is an enlarged star~oard side elevation
of the operational line reels and the pipe take-off drum
of the present invention;
, .
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- 14 -
Figure 5 is a top plan view of the enlarged
portion of the multi-reel vessel of Figure 4;
Figure 6 is a side elevation of the pi~e take-off
drum;
Figure 7 is a cross-sectional view through a
portion of the pipe take-off drum of Figure 6 taken on
line 7-7;
Fiyure 8 is a schematic side elevation view of
the Figure 3 embodiment of the pipe take-off structure
showing the straightening and tensioning devices in
greater detail;
Figure 9 is a cross-sectional view taken through
the straightening device on line 9-9 of Fiyure 8;
Figure 10 is a cross-sectional view taken through
the pipe take-off structure showing the tensionin~ device
of the present invention taken on line 10-10 of Figure 8;
Figure 11 is a cross-sectional view of the pipe
take-off structure in Figure 8 showing the pipe alignment
clamp taken on 11-11 of Figure 8;
Figure 12 is a side elevation view of the pipe
take-off drum support frame structure;
Figure 13 is a front view of the support frame _
structure of Figure 12,
~'igure 14 is a top plan view of the support frame
structure of Figure 12;
Figure 15 is a partial cross-sectional side
elevation view of the pipe take-off assembly WitllOUt the
take-off drum of the present invention;
Figure 16 is a partial cross-sectional view
through the hydraulic power drive motor by which the pipe
take-off structure is rotated to establish different water
entry angles for the pipeline array;
Figure 17 is a side elevation view of the
staightener device of the Figure 8 embodiment;
Figure 18 is a top plan view of the straightener
device of Figure 17 with the sprocket chain tracks removed;
~26i~156
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Figure 19 is a cross-sectional view taken on line
19-19 of Figure 17 showing the adjustable idler rollers
and the o~erational lines support pads mounted on the
sprocket tracks;
Figure 20 is a front schematic plan view of the
first auxiliary reel mounted on the vessel deck showing
the level wind transverse positioning;
Figure 21 is a front schematic view of the
secondary auxillary reel mounted on the vessel deck;
Figure 22 is a side elevation view of the second
auxillary reel showing details o~ the reel;
Figure 23 is a front plan view of the reel of
Figure 22;
Figure 24 is a tranverse view of the level wind
track assembly mounting the second auxillary reel on the
vessel deck;
Figure 25 is a longitudinal cross-sectional view
of the level wind support assembly of Figure 24;
Figure 26 is a side elevation view of the
structural frame support for the second auxillary reel;
Figure 27 is a front plan view of the structural
frame support of Figure 26;
Figure 28 is a top plan view of the structural
frame support of Figure 26;
Figure 29 is a side elevation view of the first
auxillary reel and its support frame structure when
mounted on the vessel deck;
Figure 30 is a front plan view of the auxillary
reel shown in Figure 29;
Figure 31 is a longitudinal side elevation view
of the level wind tower associated with the main reel;
Figure 32 is a transverse front elevation view of
the level wind tower assembly associated with the main
reel;
Figure 33 is a side elevation detailed view of
one of the multiple track tensioners assemblies of Figures
3 and ~;
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- 16 -
Fiyure 34 is a top plan view of the tensioner
assembly of Figure 33 with the multiple tracks removed;
Figure 35 is a cross-sectional view of the
tensioner device of Figure 33 taken on line 35-35;
Figure 36 is a schematic side elevation view of a
second embodiment of the pipe take-off structure of the
present invention showiny the internally positioned
multiple track straightening/tensioning assemblies;
Figure 37 is a detailed cross-sectional view of
the multiæle track straightening/tensioning assemblies
shown in Figure 36 taken on lines 37-37,
Figure 38 is a detailed side elevation view of
the multiple tracks straightening/tensioning assemblies of
Figure 36 and 37;
Figure 39 is a starboard side elevation general
arrangement view of a third embodiment of the multi-reel
vessel of the present invention;
Figure 40 is a top plan view of the multi-reel
vessel of Figure 39;
Figure 41 is a perspective view of the pivotal
ramp and level wind carriage used on the multi-reel vessel
of Figure 39;
Figure 42 is a fourth embodiment of the present
invention showing a multi-reel vessel pivotal ram~ and
level wind carriage of the type illustrated in Figures 39
and 40 fitted with multiple track straightening/
tensioning assemblies;
Figure 43 is a starboard side elevation general
arrangement view of a fifth embodiment of the multi-reel
vessel of the present invention designed for shallow and
benign waters;
Figure 44 is a top plan view of the multi-reel
vessel of Figure 43;
Fiyure 45 is a starboard side elevation yeneral
arranyement view of a sixth embodiment of the multi-reel
vessel of the present invention also designed for shallow
water operational lines layout.
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Figure 46 is a top plan view of the multi-reel
vessel of Figure 45; and
Figure 47 is a ~chematic front elevation-
transverse view of the operational lines take-off device
used on the vessel of Figure 45 and 46.
DESCRIPTIO~I O~' THE PREFEkRED :~lBODIM~NTS
The multi-reel vessel 10 of Figures 1-5 has a
hull 12 which is constructed with starboard and port main
reel support structures 14 and 16 which are elevated above
the fore deck 16 and the aft deck 18. These reel support
structures rotatably support a main reel 20 wllich is
positioned with its axis transverse to the vessel
longitudinal axis and which is adapted to provide storage
for a series of wraps of rigid walled pipeline which can
be wound in single or multiple line fashion. A detailed
disclosure of the vessel hull 12 and main reel 20 is set
forth in U.S. Pat. No. 4,269,540.
A single pipeline 22 is shown being unspooled
from the vertically disposed main reel 20 onto the pipe
take-off assembly 24 which includes as a main element a
pipe take-off drum 26 positioned adjacent the stern 2~ of
vessel 10. The assembly 24 also includes a pipe take-off
structure 30 in which a straightening device 32 is
supported in forceable contact with pipeline 22. A
tensioning device 34 is also included within the pipe
take-off structure 30 for the handling of the operational
lines array 35. The structure 30 rests in a stern notch
29 when in its vertical 90 position as shown in Figures
and 2.
A first auxiliary reel 36 is mounted on a reel
support frame 38 on the aft deck 18. Also a second
- auxiliary reel 40 is mounted on a reel support frame 42
35 which is also supported on aft deck 18. Operational lines
44 and 46 are unreeled from auxiliary reels 36 and 40
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simultaneously with the unreeling of pipeline 22 from main
reel 20. All of these-operational lines are gathered into
an initial horizontal juxtaposed configuration at the top
-of the take-off drum 26 and are maintained in continuous
contact with the periphery thereof as the direction of
movement of these operational lines is changad from
horizontal to vertical at the stern end o~ the pi~e
take-off drum 26. In this embodiment the pipe take-off
assembly functions as the operational lines layin~ device.
The contact between the operational lines 22, 44
and 46 with the periphery of the pipe take-off drum 26
results in the linear velocity of layout of all of these
lines being equal. Upon changing of the direction of
movement from horizontal to any angular pipe take-off
position the operational lines are then passed through the
straightening means 32 and the tensioning device 34 so
that the array of these lines passes downwardly over the
stern 28 at nearly a 90 angle as shown in Figure 1 for
deep water layout.
A level wind assembly 48 is provided for aiding
the s~ooling of pipeline onto main reel 20. The level
wind feature is not used during unspooling sinca the
pipeline is merely passed through tnis device so as to
restrain the lateral movements. An a~andonment and
recovery (A/R) cable storage reel 50 is mounted to fora
deck 16 for the storage of two cables 52 and 54 which are
strung out under main reel 20 by a fixed-cable double
groove sheave 56 and a series of cable rollers 58 and 60
through a twin drum traction winch 62. Tne A/R functions
of the cables 52 and 54 combined with operation of the
traction winch 62 are described below.
A control tower 64 is mounted on the starboard
reel support structure 14.
Pedestal cranes 66 and 68 are provided on
starboard and port sides, respectively.
~6~56
-- 19 --
As shown in Figure ~, starboard-and port exhaust
stacks 70 and 72 are provided for the diesel engine(s)
used to power vessel 10. As required lifeboats 74 and 76
are provided on port and starboard decks at midship. The
A/R cable storage reel 50 has two ~rum yortions 78 and 80
for storing the two cables 52 and 54 separately.
Rotatable mounting bearin4s 82 and 84 are shown
on either side of main reel 20 in Figure 2. ~he main reel
20 has a hub 85 on which the successive turns of pipeline
are wound.
The vessel 10 has fore and aft lateral thrusters
86, 88, 90 and 92 positioned below the water line 94 to
provide for the dynamic positioning of vessel 10 during
unspooliny of the operational lines. Thus vessel 10 is
capable of dynamically positioning itself.
Operational Lines Laying Device
Figure 3 shows, in general, the operation of the
straightener device 32 which comprises a first track
assembly 102 for contacting the operational line array
35. The straightener device 32 has idler roller-s
described below which can be ad~usted to provide for
various curvatures in the operational lines array 35. T~e
tensioning device 34 is formed by a second track assembly
104 and a third track assembly 106 which act on opposite
sides of the operational line array 35, respectively, in
order to provide tension for supporting the pipeline
weight which is suspended from the pipe take-off assembly
24.
In order to straighten rigid walled pipeline,
force must be exerted against three zones of the
pipeline. The peripher~ of the pipe take-off drum 26
provides the force zone as the straightening device 32
provides the force zone B,- within which the curvature must
change while the fore track assembly 10~ of the tensioning
device 34 provides the third force zone C. The pipeline
array 35 is then passed downwardly througn t-he pipe
-:
:
~26~56
- 20 -
take-off structure 30, through the pipe aliyner 10~ and
into the body of water 110. A pipe clamp 112 is also
positioned within the pipe take-off structure 30 in order
to change the-position of the rigid wall pipe 22 with
respect to the operational line array 35 over small
distances.
The entire pipe take-off structure 30 is mounted
on a support frame structure 114 which is in turn
rotatably mounted on axle 116 of the pipe take-off drum
26. A hydraulic motor 118 is mounted on a support
carriage 120 and is arranged to provide power to a
peri~heral welded chain track on the curved outside
surface of frame structure 114. In this manner the frame
structure 114 and the attached pipe take-off structure 30
are rotated relative to the support carriage 120 in order
to obtain various angles of pipe water entry. The angle
shown in Figure 1 and 2 is approximately 90 whereas the
angle shown in Figure 3 is approximately 60. As
mention~d above the rotational motion of the pipe take-off
structure 30 can be varied between about 18 to a~out
90. This permits the pipe take-off structure or
operational lines laying device of the present invention_
to layout operational line array in shallow waters less
than 200 ft. depth for which low anyles are used or in
deeper waters beyond 3,000 ft. for which laryer angles of
from 60 to 90 are used. The pipe take-off assembly 24
includes the drum 2~, the pipe take-off structure 30, the
support frame structure 114 and the support carriage 120
with its underlying level wind track assembly. The
assembly 24 functions as the operational lines laying
device.
Operational Lines
The operational lines 22, 44 and 46 can be a
variety of types and for a wide range of functions. ~t
least one of the lines is a rigid walled steel or metal
pipeline which is stored on the main reel 20. Tlle other
~l2~5~
- 21 -
two operational lines 44 and 46 can be also rigid walled
steel or metal pipelines or they can be plastic lines,
electrical cables, tension support cables, etc. Some or
all of these lines can be thermally insulated. Operating
examples are that the line 22 can be a 6" o.d. rigid
walled pipeline; the line 44 can be of 4" o.d. rigid
walled pipeline; and the line 46 can be eitiler a single or
dual set of electrical lines. All of these lines are
passed over the pipe take-off drum 24 and are also passed
through the straightening device 32 and tensioning device
34 even though the electrical line 46 does not require
straightening.
Various numbers of operational lines from 2 to
about 8 can be laid out from the vessel of subject
invention.
Another aspect of the operational lines is that
these can be lines which have an outer sheath formed about
a number of smaller lines which are bundled within the
sheath. The sheath for such bundles of lines can be
either continuous walled or in the form of a bundle
wrapping. The lines in the bundles can be combined with
either sin~le lines or other bundled lines to form
operational lines arrays stored on the multi-reel vessel
10. Examples are that a 3 inch or 4 inch o.d. sheath line
can have approximately fifteen 1/2 inch lines within the
same bundling sheath. Electrical control lines can also
be bundled within a sheath.
The main reel 20 can accommodate rigid walled
pipe of from 2 inch to 16 inch o.d. The first auxiliary
reel 36 can accommodate from about 2 inch to approximately
9 inch o.d. rigid walled-pipe-line or other operational
lines such as electrical cables or tension support cables.
The second auxiliary reel 40 can be utilized for
about 2 inch to about 5 inch o.d. rigid walled pipelines
or tension support cables or electrical cables. ~le
diameter range of the riyid walled pipelines which can be
~26~5Ç;
-- 22 --
stored on and unreeled frolll the auxiliary reels is a
function of the hub diameters of those reels as specified
below.
In o~erating line arrays it is often desirable to
utilize the main reel 20 and the first auxiliary reel 36
for rigid walled pipelines and to utilize the second
auxiliary reel 40 for the storage and layout of electrical
lines and tension support cables.
Also shown in Figure 4 is the boom 122 of the
pedestal crane 68. The elevation cable 124 is also shown
attached to the top of the crane arm 126.
Pipe Take-Off Drum
Figures 6 and 7 show the outer rim 130 and a
central hub 132 of the pipe take-off drum 26. Tne hub is
connected to the peripheral rim 130 by a series of
circular spokes 134-156. ~he connection at the center of
the hub is formed by a central cylinder 158 which is
mounted on a rotatable axle 116. A series of starboard
hub gussets 162-184 are intergrally connected to the
cylinder 158 and to a starboard flange riny 186. A
similar series of port side construction gussets are
connected to cylinder 15& and to a port side flanye ring_
188 as illustrated by port gussets 190 and 192 in Figure 7.
The spokes are connected to the rim structure 130
by a series of starboard peripheral gussets 194-216 and by
a similar series of peripheral gussets on the port side as
shown by gusset 218 for spoke 136 in Figure 7.
Operational lines supporting means ~20 are
supported about the periphery of the take-off drum 24 and
are constructed as a series of interconnected annular
grooves 222-232 to provide for continuous contact with the
operational lines duriny contact t~lereof during the layout
operation. Due to this frictional contact and the
interconnected nature of the supportiny means grooves the
layout velocity of all the operational lines is equalized.
The supportiny means 220 is mounted on a rim 234 which is
~2~ 56
-- ~3 --
integrally connected to the ends of the spokes as shown
~or spoke 136 in Figure 7. An internal reinforcement rim
236 is spaced below the outer rim 234 and is connected
thereto by the starboard and port peripheral gussets 196
and ~18 respectively as shown in Figure 7.
Starboard and port side rims 238 and 240 are also
connected to the outer rim 234 and extend upwardly on
either side of the ol~erational lines supporting means
220. The grooves 222-232 form indented configurations
which extend partially around the outer diameters of the
operational lines placed in the same durin~ the layout
operation. The number and sizes of the grooves can be
varied depending on the particular operationals lines
requirements of a given job. For this purpose, the
support means 220 is constructed in removable arcuate
segments in order to accommodate varying numbers and
diameters of operational lines.
Also shown in Figure 7 are the internal gussets
242 and 244 which are representative oE the series of such
gussets provided for interconnecting the inner and outer
rims 234 and 236 with the terminal portions of the drum
spokes.
The diameter of the pipe take-off drum 26 is
chosen so as to layout the operational lines with residual
ovality lower than the maximum limits specified by the
international certification organizations. Tnese ovality
limits are not necessary for all offshore construction
projects so that specific pipelines can be laid without
observing such limits.
It has been found satisfactory to size the drum
26 radius with respect to the ~i~eline diameter. The wall
thickness of the pipeline is also of interest with respect
to the pipe diameter. A satisfactory set of
relationships for sizing the drum 26 radius is:
R z 18 D (1),
where R is the drum 26 radius measured to the pipeline
center in given units; and D is the pipeline outer
.. . , , . _ . .. ..... .... ....
~2~
- 24 -
diameter measured in the same units. A correlated
relationship of ~ipeline diameter to pipeline wall
thickness is expressed by:
D/T ~ 30 (2)
, where D is pipeline outer diameter in given units and T
is pipeline wall thickness in the same units.
A preferred relationship is:
R ~ 20 D (3)
, where R and D are as above defined.
Straightening And Tensionin~_Assemblies In General
The pipe take-off assembly 24 yenerally described
in Figure 3 is shown with greater detail in Figures 8-11.
The pipe take-off structure 30 and support frame structure
114 are integrally constructed with a top port side radial
frame member 250p which extends from its connection with
a bearing sleeve mounted on the pipe take-off drum axle
116 beyond the periphery of the drum 2~ and an aft beam
252p which is perpendicularly connected to that top side
frame member at its stern end. An intermediate frame
member 254p is connected to the end of a radial frame
member 256p which has the other end thereof intergrally
connected to the bearing sleeve 257p (Figure 15) on the
drum axle 116. A third radial beam 258p is also
connected to the sleeve 257p about drum axle 116 and
extends beyond the periphery of drum 26 in order to form
the fore frame section of the pipe take-off structure 30.
Arcuate cradle members 260p and 260s are connected
between the starboard and port radial frame members 250,
256 and 258 and are designed to rotate with tnese members
about the periphery of drum 26. The frame members
250p-260p form the port side of the structural su~port for
' pipe take-off structure 30. A corresponding starboard set
of structural members are connected to the above described
port side set by transverse frame members 262, 263, 264,
266, 267, 268, 269, 270, 272, 273, 274, 276 and ~78 which
are interconnected at the framing juncture points between
~26~l5~ `
-- 25 --
the starboard and port frame members (in clockwise
positioning from lower right).
Starboard and port sets of parallel structural
guides are ~rovided for adjustably mounting straightening
device 32 and the two halves of tensioning device 34
within the pipe take-off structure 30. Port structural
guide set 2~0p has three parallel 5 internal guide frames
282p, 283p and 284p which are connected by the aft end
thereof to the transverse frame members :~72, ;~73 and :~74,
respectfully. The fore ends of the internal guide frames
282p, 2~3p and 284p are connected to matched exterior side
frame members illustrated by frame 285p via spacers
illustrated by 286p in Figure 9. This side frame 285p is,
in turn, connected to arcuate cradle member 260p.
A similar port set of parallel internal guide
frames 287p is provided for the tensioning device 34 by
guide members 288p, 289p and ;290p which are connected at
the aft end thereof to transverse members 267, 268 and 269
and to port and starboard side spacer members as shown by
20 members 2g2p and 292s (Figure 10). A matching set of
internal guide frames 288s, 289s and 290s are positioned_
on the starboard side of the pipe take-off structure 30
for guiding the aft positioned second track assembly 104
which forms part of the tensioning device 34. These
25 internal guides are reinforced by matched exterior ~ide
frame members illustrated by frames 294p and 294s in
simi.lar fashion to that described above for the
straightening device 34. The third track assembly 106
which forms part of the tensioning dev~ce 34 is similarly
30 set in internal guide frames 296p which is formed by
parallel structural members 298p, 299p and 300p which are
affixed to the side frame members as shown by frame 294s
(Figure 10) and then to arcuate member ~60p. Side spacer
members 302p, s and 304p, s, respectively, are provided for
35 positioning the middle internal guides 299s, p.
A starboard set of structural guide members 298s, 299s and
~26~l5~
- 26 -
300s, are also provided for mounting the third track
assembly 106. The lower guide frames 300p and 300s are
spaced from matched exterior frames by similar spacers.
The straightening device 32 is formed by the
first track assembly 102 and the hydraulic positioning
-~ rams 306p and 306s which are positioned on the port and
starboard sides of the main track carriage 308,
respectively. Guide rollers 310p, 311p and 312L~ are
rotatably mounted on the port side of carriage 30~ in a
position to contact the internal guide frames 282p 283p
and 284p, respectively. The operation of the rams 3~6p
and 306s permit both sliding, Sl, and pivotal , S2,
adjustment of the first track assembly 102 with respect to
the upper and lower positioned internal guide frames 282p,
s, and 284p, s. The hydraulic rams 306~ and 306s are
pivotally connected by fixed ears 314p and 314s to the aft
structural spacer member 273. The hydraulic ram pistons
316p and 316s are also ~ivotally connected to the port and
starboard sides of the main carriage 308, respectively,
via connections 317p and 317s (Figure 9). Sprocket gear
wheels sets 318 and 320 are rotatably mounted in bearings
on the top and bottom ends of the main carriage 308 for
supporting a correspondin~ series of track mechanisms
322. Adjustable sprocket gear sets 324 and 326 are
mounted on the aft side of the main carriaye 308 on
~ hydraulic cylinder mounts 325 and 327, respectively, for
additionally supporting the series of track mechanisms 322.
The series of track mechanisms 322 are further
described below with reference to Figures 9, 10 and
17-19. Tne first track assembly 102 has an idler assembly
generally designated as 328 which provides a series of
idler roller sets which force the flexible chain tracks
322 into contact with the operational lines array 35.
Further details of the operation of the first track
assembly 102 and the idler roller assembly 32~ are set
forth below. Jactuator adjusters 329 are provided to
. :
~2~1156
manually change positioning of the rollers to establish
selected curvatures. The mounting and o~eration of the
straightener device 32 permits various curvatures to be
formed by the flexible sets of tracks 322.
The second track assembly 104 which, in part,
comprises the tensioner device 34 is also positioned by
hydraulic rams 330~ and 330s which are positioned on
either side of the second track assembly main carriage
base 332. Port side guide rollers 334~, 335p and 336~ are
rotatably mounted on the port side of the main carriage
member 332 (shown in Figures 33 and 34) for engaying the
parallel structural guide members 288p, 289p and 290~,
respectively. Starboard guide rollers 334s, 335s and 336s
are provided for the starboard side of the main carriage
332 and for contacting the corresponding structural guides
288s, 289s and 290s.
A similar set of shorter rams 338p and 338s are
provided for the third track assembly 106 w~lich forms t~le
second part of the tensioning device 34. ~he third track
assembly is positioned by these rams within the ~ort and
starboard structural guide sets 298s, p, 299s, p and 300s,
p. Guide rollers 340p, 341p and 342~ are positioned on
the port side of main carriage member 344 for providing
rolling contact along the port guide frame sets 298p,
299p, and 300p.
~ydraulic motors 34~s and 348s are provided for
the starboard side of track assembly 104 in ord~r to drive
a set of flexible chain tracks 349 which are mounted on
corresponding sets of driven sprocket gear~ 350 and 351,
respectively, shown in Figure 34. An idler roller
assembly 352 is provided for the set of tracks 349 and
corresponds in relative position to the idler assembly 32
for the first track assembly 102. Figure 10 shows
representative adjustment cylinders 353s, p which permit
variation in applied force for the idler roller assembly
352. ~he opposing operational lines support pads pairs
~6~5~i;
- 28 -
354a and f are positioned on either side of the
operational lines array 35O Also configured backup
rollers 355a and 355f are shown in phanton as used for
assemblies 104 and 106.
Similar guides and idler assemblies are provided
for the third track assembly 106. The detailed
description of track assemblies 104 and 106 is set forth
in connection with Figures 33-35, below.
An alternate track assembly arrangement for the
third track assembly 106 is to mount the hydraulic rams
338p and 338s between the main carriages 332 and 344 of
the two opposing track assemblies 104 and 106. It is
necessary to provide for imposition of different forces on
the operational line array by these two opposed track
assemblies since track assembly 106 provides the third
force zone of a three zone strai~htening system as
described with respect to Figure 3. The force exerted at
the third zone for straightening is of course separate
from the tensioning force which is exerted through any
~0 alternate hydraulic rams connected between the main
carriages. In this modification the hydraulic rams 330s_
and 330~ would provide the straighteniny force exerted by
assembly 106.
Other features of the pipe take-off structure 30
are the pivotally connected workiny floor pan~ls 356 and
358 which can be adjusted with respect to various
operating positions of the cradle member ~60p. Also a
lower winch housing 3~0 and A/R cable winch 362 are
attached to the bottom side structural members 346s and
364p on diagonal aft beams 363p, s which are mounted at
the bottom ends thereof on base side beams 365p, s. Fore
positioned diagonal beams 366p,s are also mounted on the
base side beams 365p, s.
A pipe clamp 367 is positioned within the
operating lines array opening 368 which is formed by an
open box structure 369 constructed of I beams 369a,f,p,s.
~2611~
- 29 -
A pipe aligner double clamp set 370 is pivotally attached
by a connections 372s and 372p to the interior of the
frame members constituting the pipe ta~e-off structure
30. This pipe aligner clamp set has two hydraulic rams
374 and 376 which are coordinated to operate a clamp about
the rigid walled pipe lines in order to align the same
within the operational line array 35. The two hydraulic
rams can be utilized for positioning and aligning all of
the rigid walled pipes within the operational lines array.
Pipe Take-Off Support Carriage:
The support carriage 120 of Figures 12-14 has a
starboard base longitudinal beam 390 which is connected to
fore and aft transverse beams 392 and 394. The port side
of these structural beams are connected to a port frame
member 39,6 to complete a generally rectangular frame base
construction. Additional intermediate base frame members
398 and 400 (Figure 13) are provided parallel to the
starboard and port beams 390 and 396. Upon this base
frame a starboard bearing housing 402 is su~ported by a
20 series of six structural members 404, 406, 408, 410, 4i2
and 414 are secured at the bottom ends thereof to the
above-described frame base members. The bearing housing-
402 provides rotational support for the axle 11~ of the
pipe take-off drum 26. A similar port side bearing
housing-415 is supported by the six port side structural
members 416-426 which are secured at the lower ends
thereof to the frame members above described.
The bearing housings 402 and 415 are separated by
a distance sufficient to accommodate the drum 26 and the
30 support frame structure 114. A gusset frame 426 is also
positioned between the bearing collars 402 and 415 at the
fore end of carriage 120 and contains two hydraulically
operated locking pins 428 and 430 for engaging openings in
the periphery of the cradle members 260p and 260s in order
to secure the same against rotation when mounted between
the bearing housings. This gusset frame 426 is
_ , _ . ... . ..... . .
L5~
- 30 -
constructed of vertical members 427p and 427s and
diagonals 429p and 429s. The vertical lengths of the
structural supporting members 404-414 and 416-426 are ~-
sufficient to accommodate the pipe take-off drum 26.
Also provided on carriage 120 are a series of
reinforcement gussets 432, 434, 438 and 44~ as shown
immediately under bearing collar 402~ A similar set of
reinforcement gussets denoted as 442 are provided for the
port beariny collar 414.
Carriage 120 is mounted for transverse level
winding movement of a support frame by roller caster sets
444 and 446 which are positioned on the fore structural
member 392~ A similar set of roller casters 448 and 450
are connected to the aft base structural member 394.
Additional reinforcing base frame members 452,
454 and 456 are provided as shown in Figure 14 in order to
provide additional rigidity for the base frame. Also a
cross beam reinforcement assembly 458 is provided within
the gusset bracket 426. Openings 459s and 459p are
provided in diagonal supports 429s and 429p for
accommodation of hydraulic motor drive gears as describe~
for Figure 16, below, for o~erational rotation of the
support frame structure 114.
The pipe take~off structure 30 and its associated
cradle support frame structure 114 of the pipe take-off
assembly 24 are shown in Figure 15 with drum 26 removed.
The resulting view is in the nature of a cross-sectional
elevation taken on line 15-15 as shown in Figure 5. The
configuration of the frame members of the take-off
structure 30 as attached to the arcuate cradle frames
260s,p is shown by this Figure 15. Structure 30 houses
the straightening device 32 and the tensioning device 34
as described with respect to Figure 8 above.
Frame members within this take-off structure 30
can be extensions of the spoke members 250p, 256p, and
259p which are connected by their radial innermost ends to
~26 ~3~56
the bearing sleeve 257p which is rotatably mounted on axle
116. A radial spoke member 462p is integrally affixed to
bearing sleeve 257p on the opposite side from its
connection with frame spoke member 256~. The radial outer
end of spoke member 46~ is connected to the upper fore
end of arcuate frame member 260p. In a like fashion spoke
frame member 250p forms an integral connection with the
arcuate frame member 260p on its radial outermost end.
Additional frame spoke members 466p, 4~8p and 470p are
provided between the collar 257~ and the arcuate frame
member 260p. A sprocket chain track 472p is affixed to
the peripheral rim 474~ of cradle frame member 260p. The
hydraulic motor 118s is affixed to the support carriage
120 and is fitted with a drive sprocket gear tFigure 16)
which interfi~s with the sprocket chain 472s in order to
rotate the frame structure 114 about the axle 116. m e
frame structure 114 and the attached pipe take-off
structure 30 are thus rotated about axle 116 which is
supported by the support carriage 120 and the brace
members mounted on the starboard and port sides thereof as
described with respect to Figures 12-14 above. Thus the_
support frame structure 114 fits within the space between
the bearing collars 402 and 415 in Figures 13 and 14 on
either side of the drum 26. The port side support braces
416, 426 and 424 of the support carriage 120 are shown in
phantom lines.
Level Wind Feature Of Pipe Take-Off Assembly
. _ .
The support carriage 120 is mounted on transverse
support beams 476 and 478 which are affixed to the main
deck 18 of vessel 10. These are "T" cross-section beams
and the roller supports 444 and 44~ are positioned under
the carriage 120 are designed to fit under the top side
edges of the "T" configuration of these sup~ort beams in
order to permit transverse movement of carriage 120
together with the supported pipe take-off structure 30 and
the frame structure 114. The configuration of the roller
~lZ6~
-32-
brackets is such that rollers are ~isposed both on the top
surface and below the top portion of the "T" support beam
whereby the pipe take-off assembly will not be rolled or
pitclled off from the support beams 476 and 478 in heavy
seas.
Also shown is the fore gusset frame 426 within
which is mounted the hydraulic cylinder pin 428w~ichis
designed for entry into openings on the starboard rim 474s
of the cradle member 260s in order to prevent rotation of
the same from a given fixed working position. A matching
cylinder pin 430is provided for entering openings in the
port cradle frame 260p.
Also shown in Figure 15 are the guide frames
282p, 283pand284p which provide tracks for the
15 straightener device 32. The intermediate guide frames
283p and 283s are connected by spacers to exterior frames
shown as 285p and 285s in Figure 9. These exterior frames
serve to transmit force from the cross brace 273 forward
to the arcuate frame members 260p and 260s when the
20 hydraulic rams 306p and 306s are exertiny force on the
main carriage 308 of the straightener device 32.
In similar fashion exterior frame 480p an~ an
intermediate exterior frame 482p are associated with
structural guide set 287p. The intermediate frame pair
25 482p and s provide for the transmission of force exerted
by hydraulic rams 330p and 330s to arcuate cradle members
260p and 260s.
Also shown in Figure 15 are a series of plating
panels 484p, 486p, 490p, and 492p which are successively
30 forward positioned up to a triangular panel shape member
494p, which is located in the fore ~osition of the pipe
take-off structure 30.A series of openings 496 are
provided at locations along the edges of the panel members
in order to provide interior lighting for the pipe -
35 take-off structure 30 which is of course also lit by known
marine lighting devices.
~2~LS6
- 33 -
An entry port 498p is provided as shown in
mounting panel 500p. This port is used for gaining access
to the work floor area 355 via a stair set mounted on
carriage 120 (not shown). T'he pivotal working platforms
356 and 358 are shown in their horizontal down positions
in Figure 15. The subfloor base frame 365 is shown spaced
below the support floor frame 364p and the interconnected
diagonal braces 363p and 366p.
Pipe Take-Off Structure Rotatlon
The support frame structure 114 of the pipe
take-off "assembly 24 is rotated into various angular
positions by hydraulic motor 118 as shown in Figures 15
and 16. A sprocket chain gear 506 interfits with the
sprocket chain 472s which is in turn mounted on cradle rim
474s. In the preferred embodiment described herein, only
a single hydraulic motor 118 is employed. If desired this
hydraulic motor shown in thé starboard position with
respect to the frame structure 114 can be balanced by a
similar hydraulic motor also mounted on carriage 120 on
the port side thereof. In this event a second sprocket
chain is also utilized on the port edge of the rim 474p.
As shown in Figure 16 the sprocket gear 506 is
fitted with a mounting shaft 508 whi~h is integrally
a-ttached within gusset frame member 429s of the gusset
frame 426. A bushing 510 provides for rotation of
sprocket gear 506 about the mounting shaft 508.
The sprocket mounting adapter 512 of hydraulic
motor 118 is designed to rotate within the stationary base
514 to thereby transmit rotational force to the sprocket
gear 506 which is interconnected thereto by a series of
bolts shown as 516 and 518. The hydraulic motor front
bracket 520 is integrally affixed to a pump base 522 which
is in turn integrally connected to the carriage frame
120. A useable hydraulic motor 118 is a ~agglunds Series
80, Model No. 83~5.
6~S6
- 34 -
The angular rotation of the frame structure 114
about axis 116 in turn controls the position of the
operational lines exit port with respect to the stern 2~
of vessel 10. This angular positioning controls the water
entry angle of the operational lines array 35. ~igher
entry angles up to 90 degrees are used for deep water
layouts. The hydraulic cylinder pins 42~ and 430 secure
the various set positions.
STRAIGHTENING AND TENSIONING DEVICES IN DETAIL
The straightening device 32 shown and described
in reference to Figure 8 can be constructed with the track
assemblies 102 arranged in one of several configurations.
As shown in Figure 8, the track tension idler sprocket
gears 324 and 326 can be supported on adjustment
mechanisms 325 and 327 as shown for the track sets 322.
It is also possible to provide the tension in track sets
322 by other slightly modified mechanical configurations
as described below with respect to Figures 17, 18 and 19.
The tracks 322 can be arranged with operational
line support pads extending across two or three sprocket
chains so that the operational lines array is contacted at
2 given position by a single support pad. Alternately, _
separate support pads can be mounted on each of two or
three sprocket chains in order to contact single
operational lines or pairs of lines as shown in Figure 10.
The first track assembly which contacts the
operational line array 35 after it passes over the pipe
take-off drum 26 should be capable of forming and
maintaining an adjustable curvature in order to provide a
straightening function for various sizes of rigid wall
pipes in an operational lines array~
A preferred configuration of a
straightener/tensioner track assembly which can be used
for assembly 102 and, with some modification to provide
for adequate hydraulic power, also for assemblies 104 and
106 is shown in Figures 17-19. In this configuration the
- 35 -
sprocket chain tension sprocket gears 324 and 326 are
mounted by fixed brackets 530 and 53?. The tension is
exerted on the operational lines track sets 322 by the
mounting sprocket gear sets 318 and 320 which are
integrally mounted on axles 534 and 536, respectively, on
either end of the assembly 102. These axles 534 and 436
are common to the sprocket gears 538, 539 and 540 which
are mounted on axle 534 and the sprocket gears 542, 543
and 544 which are mounted on axle 536 and are transversely
spaced from one another. Axle 534 is mounted in a bearing
housing 546 on the starboard side and in a bearing housing
548 on the po~t side. These beariny housings 546 and 548
are adjustable linearly away from the support carriage
base 308 by means of hydraulic cylinders 550 and 552,
respectively. The bearing housings 546 and 548 are
slidably mounted in fixed C brackets 554 and 556,
respectively. Identical bearing housings 558 and 560 are
provided on the opposite end of the main housing 328 for
rotatably mountin~ axle 536 and these are slidably
adjusted by hydraulic cylinders 562 and 564, respectively,
within the C brackets 566 and 568.
The C brackets are slidably mounted on extensio~s
570, 572, 574 and 576 of the starboard side plate 578s and
the port side plate 578p. Reinforcement studs 580, 582,
584 and-586 are also provided for mounting the C brackets.
The opexation of the hydraulic cylinders 550,
552, 562, and 564 permit tensioniny of the sprocket chain
track assembly 322 about the main track carriage frame
328. This frame consists of sides 588 and 590 which are
joined to the starboard and port side walls 578s and 578~
in order to complete a box frame structure. Starboard and
port side mounting brackets 592s and 592p are also
attached to the main frame 328.
Guide roller assemblies 310s, 311s and 312s are
shown attached to the mounting bracket 592s. Similar
guide roller assemblies 310p, 311p and 312p are mounted on
~26 ~
- 36 -
the port side bracket 592p. Guide roller assembly 310s
contacts the frame guide member 282s which can be
projected ~rom Figure 8. Similarly roller guide assembly
311s contacts frame guide 283s and roller guide 312s ~~
contacts frame guide member 284s. The port side roller
assemblies 310p, 311p and 312p contact the corresponding
port side frame guide members 282p, 283p and 284p as shown
in Figure 8. Thus, movement of the track assembly 102
toward and away from the pipeline array 35 is provided by
10 operation of the hydraulic rams 306s and 306p. The piston
rod connection mounts for the hydraulic rams are denoted
as 317s and 317p and are formed in the side walls 578s and
578p and also in the mounting brackets 592s and 592p in a
centrally disposed location close to the pipeline
contacting position.
The use of only two guide roller assemblies on
either side of the track assembly 102 which are spaced
from the force plane in which the hydraulic rams 306s and
306p function permits a slight rocking motion of the
assembly as required to adjust to various pipeline
diameters and array configurations. This rocking motion
52 is in addition to the primary sliding, linear
movement Sl of the track assembly 102 due to operation
of the hydraulic rams 306s and 306p. These motions are
shown by the double headed arrows in Figure 8.
As shown in Figures 18 and 19 three pairs of main
sprocket "wheels or gears are positioned laterally across
the track assembly 102 and are spaced from one another
along the axles 534 and 536. Each of these pairs of
sprocket gears supports a separate sprocket chain 596, 598
and 600 as shown in Figure 19. The sprocket chain 596
, when placed about the track assembly 102 then contacts
sprocket gears 53~ and 542 (as well as idler sprocket
gears 324 and 326 on the stern side when mounted as shown
in Figure 8). The fore side of the track assembly 102
contains a series of nine curvature idler rollers 602
~l261156
which are slidably mounted within the bo~ frame of the
main carriage 308. The mounting arrangement for the
curvature idler set 602, as well as for the parallel idler
sets 604 and 606, is affected by placing partition walls
608 and 610 parallel to the side walls 578s and 578p
within the box frame in order to divide the same into
three compartments. The curvature idler sets 60~, 604 and
606 are then slidably mounted within these three
compartments.
Figure 19 shows one of the curvature idlers in
the 602 set on a mountin~ frame 612 which is slidably
mounted between side wall 570 and partition wall 608. The
mounting frame 612 is connected to an adjustment screw 614
which is in turn controlled by a jactuator 616 which can
be adjusted from a side port 618 in order to move the
carriage 612 relative to the main carriage housing walls.
These walls 570, 608, 610 and 572 together with the spacer
walls 620 and 622 form the curvature idlers support
assembly.
Each of the idlers in the idler sets 602, 604 and
606 iq similarly provided with an adjustment screw and a
jactuator for adjusting the position of the idlers in
order to contact the operational lines array with the
pipeline support pads 624, 626, 628, 630, 63~ and 634 as
shown in Figure 19. This individual adjustability feature
for each idler roller in the roller assets 602, 604 and
606 then permits various curvatures to be established for
each of the operational lines in the array.
If desired the pipeline support pads 624-634 can
be joined into a single transverse ~ad extending across
the width of the operational lines array 35 when different
curvatures between the operational lines are not needed.
The set of jactuators 636 which adjust the
position of the middle set of curvature idlers 604 are
offset from the jactuator set 638 of which jactuator 616
is shown in Figure 19 and the jactuator set 640 which
,,
~L2~ 56
- 38 -
adjusts the curvature idler set 6~6. The reverse
positioning of the jactuator operators 642 and 644 on the
middle set of jactuators 636 then permits adjustment of
this middle set of jactuators through the openings 646 and
648. The two outer sets of jactuators are adjusted by the
operators 650 and 652 as shown in Figure 19.
Straightener/Tensioner Device Variability
A number of degrees of flexibility are provided
by the straightener/tensioner device 102 as described
herein with respect to Figures 8-10 and 17-19. The more
significant of these are as follows:
1. The idler assembly 10 with its
individually adjustab~e curvature idlers permits
incremental changes in curvature of the
operational lines within the array 35. As the
pipeline array comes off the drum 26 these idlers
and their associated tracks establish the
adjusted curvature need for controlled
straightenin~.
2. The mounting of the track assembly 102
on the parallel guide frames 282s and 282p and on
284s and 284p for reciprocation 'Dy the hydraulic
rams 306s and 306~ via the roller pairs 310 and
312 mounted on either side of the track assembly
102 provides for both a reciprocal movement
denoted by the double headed arrow Sl and a
slight rocking arcuate motion denoted by double
headed arrow S2 (Figure 8).
3. The intermediate roller pair 311p and
311s provide additional sliding contact within
the pipe take-off assembly 30.
4. The sprocket chain sets 596, 598 and
~00 can be easily removed by retracting the
tensioning hydraulic cylinders 550 and 552 as
well as the opposing cylinders 562 and 564 in
order to remove the tension from the sprocket
chains. These chains may then be removed by
removal of one of the linking pins while the main
carriage 328 remains in its position within the
pipe take-off structure 30. In this manner the
pipe support pads 624-634 can be exchanged and/or
replaced in order to accommodate various
operational line arrays haviny different diameter
operational lines therein.
~Z6~156
- 39 -
5. It is also possible to operate the
tracX assembly 102 with varying degrees of
curvature for contacting the pipeline arrays by
reason of the adjustments provided by the
jactuator sets 636, 638 and 640. This is
particularly significant with respect to use of
two of the straightener/tensioner assemblies 102
as the track assemblies for tensioning device 34.
The arrangement of the pipe straightener device
32 with respect to drum 26 provides the two pipe
straightening force zones A and B as described with
respect to Figure 3. The placement of the track assembly
106 below the two force zones A and ~ permits the use of
track assembly 106 to provide a third force zone C. In
this manner the drum contributes zone A and the need for a
fourth track assembly in order to provide one of the force
zones is eliminated thus reduciny the capital cost of the
pipe take-off assembly 24.
Another advantage of the straightener device 32
and the tensioning device 34 in the locations shown in
Figures 3 and 8 with respect to drum 26 is that only a few
mechanical devices are required for providing both pipe
straightening and tensioning. This configuration permits
the contacting of the operational lines array 35 b~ the
straightening device 32 prior to engagement of the array
. by the tensioning device 34. This permits the proper
functioning of the tensioner device 34 which must be
operated in order to have the same force exerted on both
sides of the operating lines array 35. When the zone B
primary pipeline straightening force is exerted by one of
the two tensioning devices this equalization of tensioning
force is more difficult to control since zone B balances
the zone A and B forces. Therefore, it is preferred and
operationally significant to have the pipeline array
contacted by the straightener device 32 as it is unspooled
and taken off the pipe take-off drum 26 prior to contact
with the tensioner device 34.
~Z6~56
- 40 -
AUXILIARY REEL STRUCTURE
-
Auxiliary reel 36 has a range of transverse
positions across the main deck 18 of ve$sel 10 from the
port side 12p to the starboard side 12s as shown -by the
double headed arrow 660 in Figure 20 between the port side
position illustrated in full lines and the starboard
position illustrated in phantom lines.
The transverse movement from the port side to the
starboard side and vice-versa is termed the level wind
positioning of reel 36. For this purpose a level wind
track assembly 662 is provided for this auxiliary reel.
The reel is supported on the level wind track assembly by
the reel support structure 38 which is formed by two
A-frames 664 and 666 which are described in detail below.
Also shown in Figure 20 is the pedestal crane 68
which is mounted to main deck 18 above the hull 12 and
which is provided with an operating platform 668.
The second auxiliary reel 40 is similarly mounted
on main deck 18 on a level wind track assembly 670 whicn
provides for transverse movement of reel 40 between the
port position illustrated in solid lines an-d the starboard
position illustrated in phantom lines as indicated by th~
double headed arrow 672. The diesel exhaust ports 70 and
72 are also shown on either side of the second auxiliary
reel 40. The reel 40 is supported on the level wind track
assembly 670 by two support frames 674 and 676 which will
be described in detail below.
Auxiliary reel 40 and its associated level wind
track assembl~ 670 and the associated frame supports 674
and 676 are illustrated in Figures 22-28. The reel 40 is
eonstructed with a central hub 678 and an outer storaye
drum 680 on which a single or multiple wound operational
line is reeled for storage. The outer reel flanges are
illustrated in Figure 22 by the starboard side flange 682
which has a continuous sprocket chain 684 affixed to the
periphery thereof. A series of spoke frames 686-710 are
`` ~2~
- 41 -
provided for connecting the inner hub 678, the storage
drum 680 and the side rim 682 in order to form the reel
40. As shown, alternate frames spokes are connected
toward the center of the central hub 678 with the
intermediate frame spokes positioned toward the outer edge
of the central hub. Additional frame spokes are aligned
with the frame members of the starboard frame 676 and are
thus not shown. Also a reinforcing framing is placed
inside the storage drum 680 when desired.
As shown in Figure 23, the side rim 682 is spaced
from the corresponding port side rim 712 by the width of
the storage drum 680. The reel 40 is mounted on an axle
714 which is provided with axle bearin~ housings 716s and
716p. The starboard and port axle bearing housings are,
in turn, mounted on the reel frames 674 and 676
respectively. ~he starboard reel frame 674 is formed by
triangularly arranged frame members 718s, 720s and 722s
which are inclined from the frame base 724 upwardly toward
a pedestal plate 726s which provides the foundation for
the axle bearing housings 716s as shown in Figure 23.
This exterior set of slanted frame members 718s, 720s and
722s are matched by an interior set of interior frame
members 725s~ 726s and 728s which are positioned in the
vertical plane. All of these reel support frame members
are connected at their bottom ends to the reel support
frame base 724. In order to reinforce the support frame
676, side gussets 730s and 732s, as well as end gussets
734s and 736s, are provided for the starboard frame 674.
Similar gussets are provided on the port sideu
As seen in Figures 26 to 28 the same reel support
frame construction is employed on the port side of reel 40
by means of support frames 718p, 720p and 722p on the
exterior of the support frame and elements 725p, 726p and
728p on the interior position. The port side frame
supports a bearing pedestal 726p.
, _ . . . ... .. . .
~2~ L5~
- 42 -
The reel support frame base 724 is in a flat
frame configuration with starboard and port I-beams 738s
and 738p disposed to the outer sides with reinforcing
I-beams 740s and 740p spaced to the interior thereof. ~-
These I-beams are connected on the fore en~ by transverse
fore I-beams 742 and aft transverse I-beam 744.
Additional reinforcing frame pipes 746, 748 and 750 are
provided in a transverse positioning in order to
interconnect the longitudinally aligned I-beams 738 and
740. Diagonal reinforcing pipe frames 752 and 754 are
also provided in the same base plane.
Level Wind Assembly For Auxiliar~_Re_els
The level wind track assembly 760 for reel 40 is
shown in Figures 22-25. This assembly includes a pair of
transversely positioned I-beams 756 and 758 which are
positioned on main deck 18 and a hydraulic motor 760 which
is affixed to main deck 18 by a mounting pedestal 762
which is intermediately positioned between the pair of
I-beams 756 and 758. The hydraulic motor 760 is provided
with a speed reducer 764 to which fore and aft axles 766
and 768 are connected for power transmission. A fore set
of flexible couplings 770 and an aft set 772 are provided
in order to connect fore jactuator and screw assembly 774
and aft jactuator and screw assembly 776 as shown in
Figure 24. The jactuator assemblies are provided with
worm gear housings 778 and 780 within which worm gears
contact the transversely positioned screws 782 and 784.
The aft jactuator and screw assembly 776 is shown
in Figure 25 with the power transmission screw 784
extending transversely under the reel support frame base
I-beams 738s and 738p. The power transmission nut 786 is
, shown connected to the bottom of the starboard I-beam 738s.
The reel support frame 42 is mounted on the
parallel I-beams 756 and 758 by roller shoes 788s and 788p
at the fore side (I-beam 756) and 790s and 790p at the aft
side. These roller shoes 788 and 790 are constructed with
~2~ L56
a roller housing 792 which provides for-under-positioned
caster rollers 794 and 796 for contactin~ the underside of
the T configuration top end of I-beam 756 as shown in
Eigure 24. Side mounted caster wheels 798a and 80~a are
also provided for the aft roller shoes and are matched for
the fore roller shoes. The main bearing force of a loaded
wheel is taken up by an endless roller set 802 whicn is
contained within the roller housing 792 and is shown
schematically in Figure 24. Pedestal plates 804 and 804a
are mounted on top of the housings 792f and 79~a,
respectively~
The operation of the level wind track assembly
670 is provided by motive power from hydraulic motor 760
which is transmitted via the flexible-coupling sets 770
and 772 to the jactuator and screw assemblies 774 and
776. The power screws 782 and 784 then transmit
rotational power to the drive nuts illustrated as 786 in
Figure 25. Screw 782 is fitted to a fixed bearing housing
785 on the port side of carriage 4~. The reel sup~ort
frame 42 is thus caused to move transversely across the
parallel I-beams 756 and 758. Reverse operation of
hydraulic motor 760 reverses the operation as shown by
double headed arrows 672 in Figures 21 and 25.
The roller shoes 788s and 788p and 790s and 790p
permit controlled, low frictional movement of the reel 40
and the reel support frame 42 transversely across the
I-beams 756 and 758. The under positioned caster wheels
794a, 794f, 796a and 796f prevent the reel 40 from being
tossed off of the parallel I-beam tracks in heavy seas.
uxiliary Reel Operational Lines Spooling:
The auxiliary reels 36 and 40 are fitted with
hydraulic motors which are used for spooling of
operational lines on to the reels. It is preferable to
provide either two or four such hydraulic motors ~or each
of the reels 36 and 40. As shown in Figures 22 and 23,
hydraulic motors 806 and 808 are mounted on reel support
. ,.. , .~ .. , . , .~ .
i261~56
-~f ~-
frame base 724 and are provided with sprocket gears 810 as
shown in Figure 23 which are intermeshed with sprocket
chain 684. Upon operation of the hydraulic mo.tors 806 and
808 in order to rotate the reel 40 in a clockwise
direction as shown in Figure 2~, operational line(s) can
be reeled on the storage drum 680 of auxiliary reel 40.
.
During the unspooling operation the hydraulic systems
providing power to the two hydraulic motors 806 and 808
can be operated in order to provide breaking force for the
reel 40 in order to provide additional tension for the
operational lines which are being paid out over the drum
26 for layout.
First Auxiliary Reel Details
Figures 29 and 30 illustrate the first auxiliary
reel 36 supported by its reel frame 38. The construction
of the reel and support frames 36 and 38 together with the
level wind track assembly 662 is similar to the
construction described for the auxiliary reel 40 in
Figures 22-28. The main differences are in the
construction of the reel 36 wherein a series of
intermediate reinforcing members 812-840 are provided for
the radial spoke frames 842-868 which are connected to the
central hub 870 and the side rim 872 as shown in Figure
29. The operational lines drum 874 is also connected at
the starboard and port edges thereof to the frame spokes
842-868. Internal reinforcement members are provided for
the drum 874 as shown in Figure 30. Cross support beams
876 are provided for each pair of frame spokes which are
illustrated by the starboard spoke set 842-868. For each
39 of the cross beams 876 a set of three reinforcing struts
878, 880 and 882 are provided for connecting the drum 874
with the central axle 884. Internal reinforcing blocks
- 886 and 888 are also provided in this construction.
Opposite each such three-strut reinforcement brace
configurations in the reel 3b iS a two frame reinforcement
brace consisting of frames 890 and 892 which are connected
~2~5~
- 45 ~
at their outer ends to a cross frame 894 and at their
inner ends to the axle 884. This internal reinforcement
provides for a reel 36 having sufficient bearing strength
to support a load of spooled rigid walled pipeline.
A similar internal reinforcement arrangement is
preferably provided for the auxiliary reel 40.
Figures 29 and 30 illustrate the use of four
hydraulic motors 896s and 896p on the fore side of the
reel and 898s and 898p on the aft side. These hydraulic
motors are arranged to contact two sprocket chains 900s
and 900p positioned on the side rims 872s and 872p of reel
36. These hydraulic cylinders and sprocket chains operate
similarly to the hydraulic motors 806 and 808 together
with sprocket chain 684 described with respect to reel 40.
The hydraulic motors 896s,p and 898s,p are
mounted on a base frame 902 of the reel support frame 66.
As described with respect to reel 40 parallel I-beams 904
and 906 are provided for a level wind track assembly 662
which is constructed as described with respect to Figures
22-25 for reel 40.
The support frames 666s and 666p are constructed
as described with respect to the reel support frame 42
with the exception that.additional reinforcing pipe frames
908s, 910s, 912s and 914s are provided for the starboard
reel support ~rame 666s. Similar reinforcement pipe
frames are provided for the port side support frame 666p.
The two reel support frames mount the axle bearing
housings 916s and 916p as shown in Figure 30.
MAIN REEL LEVEL WIND ASSEMBLY
- 30 The main reel level wind assembly 48 is founded
on the reel support structures 14 and 16 immediately aft
; of the main reel 20. As shown in Figure 31, the mounting
bases 920s and 920p are positioned at the aft edge of main
reel 20. The assembly towers 922s and g22p have reduced
diameter extension portions 924s and 924p about which are
mounted a level wind roller carriage 926. This carriage
~2~L156
- 46 -
is supported between the tower extensions 924s and 924p by
a lower transverse frame structure 928 and an upper frame
930. The lower transverse frame 928 has-tower extension
follower sleeves 932s and 932p which permit vertical
sliding movement along the tower extensions 924p and
924s. As seen in Figure 32 in phanton t~e reel 20 is
positioned between the two towers 922s and 922p. The
level wind roller carriage 926 contains a set of
hour-glass starboard pipeline rollers 934s and 9366 which
are mounted in a box frame 938. This frame is in turn
mounted between the frame member 928 and transverse top
frame 930. A walkway structure 940 is provided below the
lower transverse frame structure 928 to permit personnel
to adjust the pipeline roller pairs 934 and 936.
The lower transverse frame structure 928 is also
connected to the upper frame structure 930 by side
supports 942s and 940p.
The upper transverse frame member 930 is provided
with tower extension coupling rings 944s and 944~ to
enable sliding movement therealong.
The pipeline roller carriage 926 is mounted
between the frame structures 928 and 930 to enable level~
windiny of the carriage in a transverse direction between
the towers as denoted by the double headed arrow 946. The
level wind arrangement power means employed is a centrally
mounted hydraulic motor 948 which operates a jactuator and
screw assembly (not shown) which is similar in operation
to that shown in Figures 22-25 for reel 40.
Adjustment screws are provided for t~e pipeline
hour-glass rollers 934s, 934p, 936s, and 936p in order to
accommodate for varying pipeline diameters. Also fore and
aft mounted pipeline support rollers 950 and 952 are
provided for additional support for the pipelines as
unreeled from main reel 20. The main reel level wind
assembly is similar to the level wind assembly 560 of U.S.
Patent No. 4,269,540.
~il3uX6
- 47 -
In operation, the power winches 954s and 954p
located at the mounting bases of the towers are utilized
for raising and lowering the roller carriage g2~ along
with its supporting transverse structures 928 and 930.
The exterior mounted winch cables 956s and 956p extend
from the winches 954s and 954p upwardly along the outside
of the columns and extensions thereto over the double
pulley sets 958s and 958p whereby they are attached to the
upper frame slide rings 944s and 944~ at connections 960s
and 960p.
The operation of the winches 954s and 954p permit
the entire pipeline roller assembly 926 and its associated
transverse structural frames 928 and 930 to be moved
vertically alony the tower extensions 924s and 924~ as
shown by the phantom lines in Figures 32 to accommodate
various pipeline wraps.
The main reel level wind mechanism 48 is operated
positively through hydraulic motor 948 and power winches
954s and 954p durin~ the spooling operation in order to
place the successive wraps on the main reel. The
- hydraulic motor 948 is not used during unspooling since
the pipe take-off assembly 24 is level wound transversel~ ~
across stern deck 28 to assure correct alignment as the
pipeline is unspooled. The pipeline is merely fed through
the hourglass roller pins 934 and 936 for additional
support against wave motion.
The winches 954s and 954p are used to lower the
roller carriage and frames 928 and 930 in a controlled
manner as the successive pipeline wraps are unspooled so
that the weight of the two frames is not on the
pipeline(s). The level winding provided for the
operational lines take-off structure 24 need not be across
the full width of the main reel since a permissible fleet
angle of about 1.5 can be accommodated on both the port
and starboard sides by the assembly 24. The fleet angle
is measured between vertical construction planes
~26~56
- 48 -
positioned parallel to the vessel longitudinal axis and
the center line of a given operation line being unspooled.
TENSIONER TR~CK AS~EMRLY
The tensioner track assembly 104 of Figures 33-35
was briefly described in relation to Figures 8 and 10.
The main carriage 332 consists primarily of a front plate
966 and a rear plate 968 wllich are spaced by internal
starboard wall 970s and internal port wall 970p.
Starboard and port mounting brackets 972s and 972p are
positioned in a central location as shown in Figures 33
and 34. These brackets consist of inner and outer spaced
inverted "U" ~haped members which are connected to
extensions of the spaced plates 966 and 968.
~igure 34 shows mounting extensions 974s ana 974p
for mounting associated bearing housings 976s and 976p. A
driven axle 977 is rotatably mounted within these bearin~
housings and hydraulic motors 346 and 978 are provided on
either end thereof in order to supply rotational power.
Reaction levers 980s and 980p are fixed to extensions 982s
and 982p of the mounting brackets 972s and 972p. Similar
mounting extensions 984s and 984p are provided for
mounting bearing housings 986s and 986~ for providing
rotational support for a driven axle 988 which is in turn
rotated by hydraulic motors 348 and 990 which have
reaction levers 992s and 992p similarly fixed to
extensions of the mounting brackets on either side.
Thé hydraulic motors 346, 348, 978 and 990 are
thus arranged to rotate the driven axles 977 and 988 in
order to rotate the sprocket drive gear sets 350 and 351
about which flexible sprocket chain sets 349 are
, positioned. As shown in Figures 33-35 two flexible
sprocket chains 994s and 994p are provided in order to
support a series of transverse mounting plates illustrated
by plates 996 and 99~ in Figure 35O A set of individual
pipeline support pads 1000 for engaging two pairs of
:~Z6~L~S6
- 49 -
operational lines having two different diameters are
affixed to the mountiny plates as shown in Figure 35.
This arrangement is distinguishable from that shown in
Fïgure 37 below where separate mounting plates are used
for each operational line or pair of lines so that various
curvatures can be established for different lines. The
tracks and support pads have been removed from Figure 34
for clarity.
The idler roller assembly 352 is formed by five
transversely disposed axles having two rollers on each
axle. The rollers contact the underside of the flexible
sprocket chain sets 349. Each of the five axles is
independently mounted on adjustment hydraulic cylinders
illustrated by cylinders 353s and 353p in Figure 35. Each
of these hydraulic cylinders can also be seen in Figure 34
top view.
The side position mounting brackets 972s and 972
are formed with hydraulic ram connection points 1002s and
1002p through both of the inverted "u" spaced members
20 thereof. ~lso guide roller assemblies 340s, 340p, 341s,
341p 342s and 342p are provided for sliding contact with
frame guide members 288s, 288p, 289s, 289p, 290s, and 290p
inside of structure 30 as described with respect to
Figure 8.
Adjustment in tension of the flexible sprocket
chain tracks 349 can be made by the individual hydraulic
cylinders 353s and 353p and also by the adjustment
hydraulic cylinders 1004s and 1004p which operate to move
driven axle 977 with respect to the main carriage 332.
30 Similar adjustment hydraulic cylinders 1006s and 1006p are
used for mounting the bearing housings 986s and 986p
respectively for moviny the driven axle 988 with respect
to the main carriage 332. An additional adjustment
hydraulic cylinder 1008s and 1008p can be provided on
either side of driven axle 988 in order to provide ~or
minor advancement adjustments in the track sets 349 during
operation~
~:26~6
- 50 -
The tensioner tracX assembly 104 described with
respect to Figures 33-35 above is usually designed so that
each of the adjustment cylinders illustrated by 353s and
353p in Figure 35 for each of the five idler roller axles
operate at the same hydraulic pressure and therefore are
subject to the same force exertion and position. This
technical fact toyether with the rather short distance
from one end of the roller assembly 352 to the other in
the direction of track travel means that this ty~e of
tensioner assembly is not designed for curvature
adjustment. Also the adjustment dimensions for movement
of the axles with respect to the mountin4 plate 966 is too
small to accommodate curvature adjustments of the type
described with respect to the straightener assembly 10~ in
Figures 17-19 above. For these reasons, the tensioner
track assemblies 104 and 106 as shown in Fiyure ~ are
utilized solely for providing tension to the operational
lines array. These are not useable for straightening
since they do not permit curvature adjustment of the type
required for use in the laying devices described herein.
PIPE TAKE-OFF_A_SEMBLY WIT~_STRAIGHTENER/TENSIONER DEVICE
A preferred form of the present invention with _
respect to operating efficiency and capital costs
minimization is shown in Figures 36-38.
This modification of the straightener/tensioner
device has the advantage of permitting the layout of a
multiple operational line array from a plurality of
storage reels at lower than expected capital and operating
costs.
In this modification the straightener/tensioner
track assembly has the capa~ility of imparting an
adjustable curvature to the pipelines in the operational
- lines array. The device is fitted with hydraulic motors
in order to exert tension on the multiple lines. Thus,
the adjustable curvature established by the idler roller
assembly provides a pipeline straightening function and
156
- 51 -
the use of hydraulic motors to power the multiple sprocket
chain tracks provides a tensioning function. By use of
this new type of straightener/tensioner assembly only two
opposing asse~blies are needed to constitute a
straightening/tensioning device which can then be
positioned within the pipe take-off structure 30. The
drum 2~ provides the first force imposition zone A while
the multiline tracks 1042 and 1044 provide zones B and C
as illustrated in Figure 36. Due to the curvatures which
can be established in the tracks the latter two zones can
be adequately spaced from one another.
The operational lines array 35 are thus gathered
and set into a juxtaposed array by the pipe take-up drum
26 shown in Figure 36 prior to entry of the pipeline array
between two opposiny straightener/tensioner multiple track
assemblies 1020 and 1022 straightener/tensioner multiple
track assemblies 1020 and 1022 which constitute the
straightener/tensioner device 1024. A planar array
positioning in which the operational lines centers are in
the same plane is preferred. Each of the
straightening/tensioning assemblies 1020 and 1022 are
slidably mounted on starboard and port structural guides_
illustrated by guide members 1026p and 1028p -for assembly
1020 and members 1030p and 1032p for assembly 1022. As
set forth with respect to Figure 8, hydraulic ram pairs
1034 and 1036 are pivotally connected by upstanding
connectors 1038 s, p and 1040s, p in order to provide
adjustment in positioning for the straightening/tensioning
assemblies. The engagement of guide rollers on the
30 structural members 1026p, 1028p, 1030p and 1032p is the
same as described with respect to the embodiment
illustrated in Figure 8. Also intermediate structural
members corresponding to 289s, p of Figure 15 are used in
this modification.
The remaining pipe handling equipment such as the
pipe aligner double clamp set 370, the pivotal floor
~2~ 56
- 52 -
panels 356 and 358, the A/R winch 362 and the pipe clamp
367 are the same as described with respect to Figure 8 and
hence the same numeral designation have been employed.
The tensioning function of the
straightening/tensioning device 1024 requires the use of
motive power for the pipeline array contacting track sets
1042 and 1044. This traction power is ~rovided by eiyht
hydraulic motors which are mounted on the two ends of each
of the four main axles in the straightening/tensioning
device 1024. Tlle starboard set of these hydraulic motors
are shown as 1046s, 1048s, 1050s and 1052s in Figure 36.
Figures 37 and 38 illustrate in greater detail
the straightening/tensioning device 1024. The two
assemblies 1020 and 1022 which com~rise device 1024 are of
identical construciion except that each of the assemblies
has the track sets mounted thereon in a configuration to
grasp the various lines in the pipeline array in order to
exert tension there along. This positioning of the track
sets then constitutes a difference between the assemblies
' when viewed side by side. In view of the identical
construction only a single set of identifying numerals
have been employed for the same elements in the two
assemblies except that the designations "a" for aft and
"f" for fore have been used to designate the operating
position of the assembly under description. The framing
members of the pipe take-off structure 30 are the same as
those described in detail with respect to Figure 8.
Straightening/Tensioning ~ssemblies
The straightening/tensioning assemblies 1020 and
-30 1022 are similar to basic construction to the
straightening assembly illustrated in detail in Figures
17-19 with the important difference that in the
straightening/tensioning assemblies 1020 and 1022
hydraulic motors are provided for driving the main axles
35 which are best illustrated in Figure 18 as 534 and 536.
The motive power for each of the assemblies is provided by
,
~Z6~56
- 53 -
the four hydraulic motors above described and illustrated
in details in Figures 37 and 38. Reaction levers 1054s,
1056s, 1058s and 1060s are provided for connecting the
stationary bases of the hydraulic motors to the assembly
starboard and port side mounting bracket~ 1062a and f as
illustrated in Figure 38. The connections of these lever
arms 1054-1060 with the assemblies is througn slot and pin
connections 1064, 1066s, 1066p and 1068s, respectively, in
order to a]low for adjustments in tensioning of the track
sets 1042 and 1044 by the hydraulic pistons 1070s, 1072s,
1074s and 1076s.
In operation the relative positions of the two
assemblies 1020 and 1022 are adjusted by operation of
hydraulic cylinders 1034s and 1036s which are shown in
Figure 38 in front of the support frames 1027p and 1031p,
respectively. A pipeline array 35 can then be passed
downwardly by rotation of the pipe take-off drum 26 and
thence through the device 1024. Upon activation of the
hydraulic ram pairs 1034 and 1036 the two assemblies 1020
and 1022 can be closed on either side of the pipeline
array so that the individual lines are caught between the
opposing line support pads which are mounted on the
endless sprocket chain track sets 1042 and 1044 as shown
in Figure 37. As in Figures 17-19 the two
straightening/tensioniny assemblies are connected at the
port and starboard sides of each of the main carriages
1080 and 1082 by pivotal connections 1084s, p and 1086s,
p, respectively.
As in Figures 17-19 guide rollers 1088s and lO90s
are positioned to support assembly 1020 on the frame
tracks 1026s and 1028s which can be understood from in
Figure 38. The central positioned guide roller 1092s is
positioned to contact the intermediate structural frame
member 1027s. Corresponding guide rollers 1094s and 1096s
and 1098s are provided on the starboard side bracket 1062f.
s~
- 54 -
The internal structure of each of the assemblies
is the same as described with respect to Figures 17-19. A
series of jactuators adjustment openings 1100 and 1102 are
shown in asse~blies 1020 and 1022 respectively. These ~~
jactuators adjustments permit the turniny o~ internally
mounted screws in order to position the multiple roller
guides independently. As shown in Figure 38 nine roller
guide sets are provided for each of three endless sprocket
chains which are employed to support the pipe pads for
three pairs of lines which constitute the pipeline array
35 as shown in Figures 37 and 38. Sight openings 1104 and
1106 are also provided through the various walls of the
two assemblies to observe rotation of the jactuators
screws therein.
The operation of the straightening/tensioning
device 1024 permits the two assemblies to be opened and
closed about the pipeline array via the hydraulic ram
pairs 1034 and 1036 whereas operation of the internal
hydraulic cylinder pairs 1070, 1072, 1074 and 1076 allows
20 the tension on the endless track sets 1042 and 1044 to be
changed. The track curvature necessary to impart the
straightening function while preservin~ the pipeline
ovality and other dimensions by this novel straightening/
tensioning device 1024 his established by the mechanical
adjustment of the various screwjacks in order to set the
guide rollers at varying positions linearly along the pipe
array. The screwjack adjustment openings are for~ed on
both the top and bottom sides of the individual screwjacks
as described with respect to Figures 17-19 above since it
is necessary to adjust the central set of screws as well
as the two outer sets of screws in a three track ~et
, system such as illustrated in Figures 37 and 38. This
type of screwjack is sometimes referred as a jactuator.
The tensioning function is provided by motive
force input through the hydraulic motors 1046s, p, 1048s,
p, 1050s, p, and 1052s, p, which are connected to the main
~LZ6~L56
- 55 -
axles as described above. The input power from these
motors permits the tensioning along the pipeline array in
an upward direction as shown in Figure 38 in order to
maintain desired operating tension on the pipeline array
which passes downwardly through the pipe array clamp 367
and then into the water.
The multiple line track sets 1042 and 1044 of
each of the assemblies 1020 and 1022 are interconnected to
one another through the sprocket gears and main axles 534
and 536. This interconnection provides for moving the
lines in the operational array at a common velocity in the
same manner as provided by the interconnected grooves of
the pipe take-off drum 26 in Figures 1-7. The pipeline
support pads on the track sets provide the supporting
means for the array.
PIVOTAL RAMP INTERMEDIATE WATER DEPTH EI~BODIM~NT MVLTI-LIN~
_ PIPELAYING VESSEL
A dynamically positioned pipelaying vessel 1110
is shown fitted with multiple reels and pipeline array
handling equipment according to the present inventlon for
aligning the array in a equipmsnt comprises multi-track
straightening and tensioning devices 1114, 1116 and 1118
as shown in Figure 41 or a single combination
straightening/tensioning device 1120 as shown in Figure
25 42. The main reel 1122 is mounted between starboard and
port main reel support structures 1124 and 1126 whicn are
mounted on either side of a control tower 1128. The
vessel is also equipped with a main reel level wind
mechanism 1130 which provides for similar functioning as
the main reel level wind mechanism described with respect
to Figures 31 and 32 above. The main reel corresponds to
main reel 20 and the first and second auxiliary line reels
1132 and 1134 correspond to reels 36 and 40, respectively,
illustrated in Figures 1, 3-5 ab~ve.
The pivotal ramp 1112 re~laces the pipe take-off
assembly 24 in this embodiment and provides the functions
~Zfi~1~6
- 56 -
of straightening and tensioning the pipeline array. It is
necessary to pivot the entire structure 1112 about the
pivot axis 1136 shown in Figures 41 and 42 in order to
achieve various water entry angles for the pipeline array.
The large mass of the pivotal ram~ and its length results
in an increase in construction costs since the vessel must
be long enough to accommodate the ramp when in a nearly
horizontal positi-on as shown in Figure 39. When this
length is then compounded by the placement of auxiliary
reels such as 1132 and 1134 a vessel of considerable
longitudinal dimension must be constructed. While the
pipe laying vessel 1110 is not as short longitudinally as
vessel 10 of Figures 1 and 2 it can nevertheless be fitted
with pipe handling equipment to permit the layout of
multiple line arrays, shown here as three lines including
a rigid walled pipeline 1138 and two additional lines 1140
and 1142. Each of these lines is supplied from the
separate reels 1122, 1132 and 1134 respectively.
The pivotal ramp 1112 is formed of a truss-work
support ramp assembly 1138 which is mounted on a rotating
fixed axle 1136 and a series of five roller carriage
tracks 1141, 1143, 1144, 1146 and 1148 which support a
level wind assembly 1150. The pipe handling equipment is
mounted on this level wind assembly and consists of
straightening and tensioning devices most of which can be
mounted in a cage 1152. A pipe clamping assembly 1154
designed to permit clam~ing of the three lines in the
array 1155 is also mounted on the level wind assembly
1150. As shown by Figure 41 and described above the
30 straightening and tensioning devices 1114, 1116, and 1118
are provided as the major pipe handling equipment. Also a
stern multi-line guide assembly 1156 is provided near the
- terminal pivoting end of the support ramp assembly. A
stairway 1158 is also provided for operational access as
shown in Figure 41.
~26~156
- 57 -
The detail construction of the support ramp
assembly 1150 and the operation thereof with a curved pipe
bending radius controller 1160 is connected to the upper
free end thereof has been described in prior patents. A
jack 1162 is provided between the roller carriage 1148 and
the pipe bending radius controller 1160 in order to change
the position thereof with respect to the incoming pipeline
and the straightening equipment. A dynamically positioned
pipe laying vessel having a pivotal support ramp assembly
for supporting a level wind assembly and a pipe bending
radius controller has been described in full structural
detail with respect to single pipelines in U.S. Patent
No.'s. 4,269,540 to Stanley T. Uyeda et al; 4,230,421 to
Springett et al; 4,3~5,855 to Uyeda et al; and 4,340,322
to Springett et al. The disclosures of those Patents are
hereby incorporated by reference as though fully set forth
herein. In view of this incorporation the description
herein has been restricted to elements which are new over
those patents or which are needed for understanding the
operations of the herein described pipelaying vessel. The
pipe bending radius controller 1160 must be made wide
enough to accommodate multiple operational lines. Since
it is frequently désired to unspool sets of multiple lines
from the various reels a width great enough to accommodate
six to twelve lines in a horizontal array is used. This
necessitates a widened level wind assembly 1150 and the
provision of support mechanisms spaced sufficiently to
provide for the use of straightening and tensioning
devices for accommodating wide operational line arrays.
Specifically, as shown in Figure 41 the supporting cage
system 1152 must be made as wide as the full width of the
level wind mechanism in order to provide for the placement
of straightening and tensioning devices for accommodating
the wide operational line arrays.
This invention incorporates the placement of
straightening and tensioning track assemblies of varying
.~Z~IL56
- 58 -
widths and numbers of track sets onto the support ramp
assembly 1138. ~s illustrated in Figure 41 the pipe
bending radius controller 1160 is formed with a curved
base and a plurality of operational lines supporting
rollers 1164. The straightener assembly 1114 can
preferably be of the type disclosed for straiyhtening
device 32 in Figures 8, 9 and 17-19 above. The track
system is fitted with single operational line support pads
so that three operational lines are provided for in the
configuration of Figure 41. This is accomplished by
exchanging the paired support system shown in Figure 19
with single support pads which act as supporting means for
the pipeline array. The straightening track device 111~
in Figure 41 can also preferably be of the same type. It
is this straightener assembly which provides the main
force for straightening of the pipe in cooperation with
forces provided by the straightening assembly 1114 and the
lower track assembly of the tensioner device 1118.
Reaction points, A, B, and C have been designated on
Fi~ure 41 for that purpose.
These preferred straightening aRsemblies 1114 and
1116 hav~ adjustable curvature multi-pipeline track
systems which permit the fitting of various pipeline
diameters into the assemblies in a much more operative
manner than when only flat or minor variations in the
contact plane of the track support pads is possible.
Hence, the assemblies of the prior patents are very
difficult to use.
The tensioner assembly 1118 can be of the same
30 type as shown for device 34 in Figure 8, 10 and Figures
34-360 This differs from previous tensioners employed in
single pipeline vessels in that multiple tracks are
provided for handling pipeline arrays so the equalized
line tension can be imparted.
The multi-line track systems of the straightener
and tensioner assemblies 1114, 1116 and 1118 are
~26~l5~
- 59 -
interconnected within each such assembly to provide for
moving the operational lines over each given assembl~ at a
common velocity.
After passing through the tensioner device 1118
the pipeline array passes over a support roller 1166 and
then through an array guide assembly 1168. The line array
clamping assembly 1154 has line clamps 1170 and 1172 ~or
the two small~r lines and a large double clamp set 1174
for the main rigid walled pipeline 1138.
It is also possible to exchange the single
pipeline track assemblies disclosed in the above four U.S.
Patents all of which are assigned to the assignee hereof,
with the herein described multi-track assemblies in order
to provide for the handlin~ of multi-line arrays as set
forth therein. The straightener assemblies of those
patents are all hydraulically operated as a gang of guide
rollers which means that the establishment of various
curvatures is not possible. It is also necessary to
adjust the positions of the operational line support pads
for various diameters of lines. The former straightening
assemblies did not provide this required deyree of
flexibility. However, if the restricted operations are ~
not objectable the former hydraulically ganged guide
roller assemblies can be modified for multiple pipelines
and used as above stated within the fairly strict
limitations. This modification would necessitate the
manufacture and storage of a wide range of the changeable
operational line track sets to accommodate a range of pipe
diameter combinations.
Pivotal Ramp With Straightening/Tensioning Device
Figure 42 shows the pivotal ramp 1112 of Figures
39-41 with a single pair of opposing multiple line track
assemblies 1180 and 1182 which are set out into a cage
1184 mounted on the level wind assembly 1150. As in
~igure 41 the three operational lines 1138, 1140 and 1142
are shown bending over the radius controller 1160 and are
156
-- 60 --
then passed through the dual function straightening/
tensioning assemblies 1180 and 1182. These assemblies are
the same as those described with respect to Fiyures 36-38.
The provision of independently adjustable guide
rollers through the jactuator adjustments provides for~the
establishment of varying curvatures in order to
accommodate different pivotal positions of the ramp
assembly 1112 which changes the optimum curvature for the
straightening function. The provision of hydraulic motors
to drive the two main axles of each of the assemblies
provides for tension longitudinally along the pipeline
array lenyth. The other components such as the
operational lines guide 1168 and the pipe clamping devices
1154 are the same for Figure 410
In operation the lines 1138, 1140 and 1142 are
placed into a horizontal array on the pipe bending radius
controller 1160 as they are unspooled from the respective
reels 1122, 1132 and 1134. The lines are then gripped on
both sides by the pipe support pads on the
straightening/tensioning devices 1180 and 1182 which are
shown in detail in Figures 37 and 38. The desired
curvature for all of the three operational lines includi~g
the rigid walled pipeline 1138 can he effected by
adjusting the individual jactuator adjustments. Force
exerted longitudinally along the exterior walls of the
operational lines by the hydraulic motors 1046s, p; 1048s,
p; 1050s, p and 1052s, p, provided tensioniny of the lines
in order to maintain the desired curvature in the lines
between the vessel 1110 and the bottom of the sea in which
the pipeline array is being laid.
The use of the independent guide roller
adjustability feature of the straightening/tensioning
assemblies 1180 and 1182 permit the accommodation of a
wide range of pipeline array configurations with a
relatively small number of track sets.
~261~56
SHALLOW WATER MULTI-REEL PIPELAY~NG VESSEL
Vessel 1190 shown in Figures 43 and 44 is
designed for layiny pipeline arrays in shallow waters up
to~about 1500 ft. in depth. The pipe exit angle or water
entry angle range is from about 18 to 30. The overall
length of hull 1132 can be only slightly longer than hull
12 shown in Figures 1 and 2. A main reel 1194 is n~ounted
on reel support housings 1196 and 1198 similar to vessel
10 of Figures 1 and 2. Also a first auxiliary reel 1200
and a second auxiliary reel 1202 are positioned on the
main deck aft of the main reel in order to unspool two or
multiple lines from these au~iliary reels into a
straightening/tensioning device 1204 which is mounted on a
level wind assembly 1206 which is in turn supported on a
truss work support base 1208. The device 1204 comprises
two straightening/tensioning assemblies of the form shown
in Figures 36-38.
Pipeline array guides 1210 and 1212 are provided
on the level wind assembly 1206 similar to the pipe
handling equipment shown in Figures 34 and 40. A pipe
cla~p mechanism 1214 is also provided on the level wind
mechanism. The three operational lines 1216, 1218 and
1220 are gathered into a horizontal pipeline array just
prior to entry into the pipe straightening and tensioning
device 1204. This device 1204 is illustrated in detail in
Figure 38 and is mounted on the level wind mechanism in a
structural cage 1222 which is similar to the cage 1184
illustrated with respect to Figure 42.
In this embodiment advanced rollers 1224 and 1226
are provi~ed for operational line 1220 since it is
po~itioned close to the fore end of the level wind
assembly 1206. An additional roller 1228 is positioned
for contacting all three of the operational lines
illustrated. The lines of course can be wrapped in
multiples on each of the reels 1194, 1200 and 1202
separately in the fashion illustrated in Figures 5-10 for
~Z61;L56
- 62 -
laying out multiple numbers between three to twelve
operational lines in the array.
A bananna ramp 1230 is affixed to the stern end
of the frame support structure 1208 at connections 1234
and 1236 (Figure 44). The bananna ram~ 1230 is adjustable
over the above range of degrees of water entry an~-le by an
hydraulically powered cantilever support 1238 which is
affixed to the fore end of the ram~ 1230. The ramp is
constructed with a lattice frame base 1240 and main side
columns 1242, 1244, 1246, 1248 and 1250. The latter four
of these side members have rollers 1252, 1254, 125~ and
1258 rotatably affixed thereon in order to provide rolliny
contact for the operational lines array 1260 as it is
unspooled from the storage reels 1194, 1200, 12~2 and
passed through the straiyhtenin~/tensioning device 1204.
If desired the bananna ramp can be replaced by a column
stabilized semi-submerged type stinger ramp such as shown
in ~.S. Patent l~o. 3,685,305 and the roller can be
separately vertically adjusted to provide for a range of
20 water entry angles. The device 1204 and the ramp 1230
function as an operational lines laying device. The
multi-line track assemblies provide operational lines
supporting means for the pipeline array.
Other features of the vessel 1190 are similar to
25 those of Figures 1 and 2 in that an A/R cable reel 1262 is
provided on foredeck 1264 and a control tower 1266 is
mounted on the starboard main reel support housing 1196.
A main reel level wind tower 1268 is provided for
controlling the positioni~ o~ the rigid walled pipeline
1216 upon spooling during the take-up procedure on to the
main reel. A pedestal crane 1270 is provided in line with
the first auxiliary reel 1200 on the portside and a
- starboard pedestal crane 1272 is provided as shown in
Figure 44. The main reel 1194 is mounted on bearing
35 housings 1274 and 1276 similar to housings 82 and 84 in
Figures 1 and 2. Exhaust stacks 1278 and 1280 are
.~
:~26~56
- 63 -
provided on starboard and portsides respectively.
Lifeboats 1282 and 1284 are also shown in Figure 44.
Thruster 1286 and 1288 on the bow and 1290 and 1292 on the
stern are for the purpose of providing dynamic positioning
for the reel vessel 1190.
The level wind mechanisms for the two auxiliary
reels 1200 and 1202 is the same as described with respect
to Figures 1-30 and the level wind assembly 1206 is the
same as described with respect to level wind assembly 1150
in Figures 39 and 40.
Second Shallow Water Multi-Line Pipelaying Vessel
~mbodiment
A second embodiment of a pipelaying vessel
designed for laying operational lines array in shallow
water down to about 1500 ft. depth is shown in Figures
45-47. This embodiment is similar to the embodiment
illustrated in Figures 43 and 44 with the important
difference that the straightening/tensioning device 1302
is a lower cost, fully operative alternate embodiment to
the use of the straightening/tensioning assembly 1204
mounted on a level wind assembly 1206. In the embodiment
of Figures 43 and 44 pipeline array guides 1210 and 1212-
as well as pipe clamp 1214 are also used.
The embodiment illustrated in Figures 45-47 as
vessel 1300 has a main reel 1304 mounted on reel support
housings 1306 and 1308 by bearing housings 1310 and 1312.
A first auxiliary storage reel 1314 and a second auxiliary
storage reel 1316 are mounted on support bases 1318 and
1320 which are in turn mounted on level wind track systems
1322 and 1324 respectively. A rigid walled pipeline 1326
and two additional auxiliary operational lines 1328 and
1330 are unspooled from the main reel 1304 and the two
auxiliary reels 1314 and 1316 in order to form a planar
operational lines array 1332 at the entry position 1334
into the straightening/tensioning assembly 1302. After
passing through the assembly 1302 the operational lines
. .
~26~56
- 64 -
array 1332 passes through a stern mounted rQller ram~ 1336
which has four or more rollers 1338, 1340, 1342 a~d 1344
mounted in a framework 1346. Stern connectors 1348s and p
are also employed to affix the ramp to stern 1350. A rub
roller 1352 is also employed.
The pipelaying vessel 1300 is also outfitted with
an A/R reel 1354 mounted on the foredeck 1356; a control
tower 1358 mounted on the port main reel support housing
1306; a main reel level wind assembly 1360 (shown in
Figure 45) and two pedestal cranes 1362 and 1364 (shown in
Figure 46). Lifeboats 1366s and 1366p are provided as are
exhaust stacks 1368s and p. Thrusters 1370 and 1372 are
mounted on bow 1374 under the waterline and thrusters 1376
and 1378 are mounted at the stern under the waterline for
providing dynamic positioning for the vessel 1300.
Straightening/Tensioning Assembly For Shallow Water Vessel
The straightening/tensioning device 1302 is
mounted on a level wind track system 1380 which is in turn
secured to aft deck 1382. A pair of
straightening/tensioning multi-track
straightening/tensioning assemblies 1384 and 1386 are
mounted on either side of operational lines array 1332 by
a frame means 1388. Side supports 1390s, p; and 1392s, p,
provide track supports for the straighteniny/tensioning
devices 1384 and 1386 both of which are mounted for
reciprocal motion within the frame structure 1388 by
hydraulic piston pairs 1394 and 13g6. Roller 1335
provides support for lines 1328 and 1330 duriny unspooling
Fi~ures 46 and 47 show the
straightening/tensioning device 1302 in greater detail.
The level wind track assembly 1380 comprises a fore track
1400 and an aft track 140~, both mounted transversely on
stern deck 1350. Each of these track assemblies has
separate hydraulic motors 1404 and 1406, respectively,
mounted on the portside of a track beam shown as T-beam
1408 in Figure 47.
~:~6~5~
- 65 -
The port end of T-beam 1408 has a mounting
pedestal 1410 which is connected to stern deck 1350. The
hydraulic motor is connected to an operator screw 1412
which is rotatably mounted in pedestal 1410. This
operator screw 1412 is mounted slightly above the T-beam
1408 as shown in Figure 47. The straightening/tensioning
assembly frame 1388 is mounted on roller shoes 1414 and
1416 which are designed to be placed on the fore and aft
sides of each of the tracks 1400 and 1402. The lower roll
sets illustrated as 1418 and 1420 in Figure 47 rests on a
roller plate 1422 and roller sets 1424 and 1426 are
designed to have rolling contact with the under surface of
the T-beam 1408. By placing four of the roller shoes 1414
and 1416 at the fore end and at the aft end of frame 1388
a secure and transversely movable straightening/tensioning
assembly 1308 is effected. Mounting nuts (not shown) are
provided in the bottom of the frame 1388 for engaging the
operator screw 1412.
Straightening/tensioning assemblies 1384 and 1386
are illustrated as having three operational lines
contacting tracks 1428, 1430 and 1432 in order to provide
straightening and tensioning for lines 1326, 132~ and 1330
respectively.
The straightening/tensioning assemblies 1384 and
1386 have been previously described with respect to Figure
38 and are mounted in the frame 1388 similarly to the
mounting of the devices 1022 and 1024 in the pipe take-off
structure 30 of Figure 36.
Operational lines support pads 1434, 1436 and
143~ are shown in cross-section as are the sprocket chains
1440, 1442 and 1444 respectively. The main support driven
sprocket gears 1446 and 1448 are also illustrated in the
partial cross-sectional view.
Four hydraulic motors illustrated on the fore
positioned motors 1450s, p and 1452s, p, are provided for
6~L56
- 66 -
operation of the tensioning force exerted on the
operational lines 326, 328 and 330.
Operation Of Straightening/Tensioning Assembly
The three operational lines are unspooled from
their respective reels into the juxtaposed position at~
1334 immediately in front of the straightening/tensioning
device 1302. The rigid walled lines within the array are
straightened by the exertion of transverse force on the
lines due to the curvature established in the
straightenin~/tensioning assemblies 1384 and 1386 by means
of the jactuator adjustments described in detail with
respect to Figure 38. The adjustment is set for a
compound pipeline array curvature so that straightening of
the pipeline can be effected by three longitudinally
separated contact areas within the device 1302.
Tensioning force is exerted on the lines by means
of the hydraulic motors 1450s, p and 1452s, p, in order to
maintain the desired curvature for the o~erational lines
as they are laid.
The operational lines as passed through the
straightening/tensioning device 1302 are then rolled
across the ramp 133~ rollers and into the water. The
operation of the unspooling is controlled by hydraulic
motors associated with each of the reels in the manner
described with respect to Figures 1-32 above.
During unspooling the straightening/tensioning
assembly 1302 is level wound transversely across the stern
deck 1350 of vessel 1300 by means of the level wind track
system 1380 in order to be in line with the pipeline 1326
unreeled from main reel 1304. The auxiliary reels 1314
and 1316 are, in turn, level wound across the main deck of
, vessel 1300 in order to provide corresponding positioning
for the lines entering the straighteniny/tensioning device
1302.
Fixed Depth/Shallow Water Operational Lines Layout
In the event that a multi-line layout project is
to be carried out in a relatively fixed depth body of
s~
- 67 -
water it is possible to utilize a series~of straiyhtener
and tensioner assemblies such as shown in Figure 41 as
assemblies 1114, 1116, and 1118 when arranged on a level
wind carriage such as the straightening/tensioning device
1302 shown in Figures 45-47. In such a modification the
carriage 1388 length is extended longitudinally along the
vessels aft main deck a sufficient distance to accommodate
all five pipe array handling assemblies. This
modification is viewed as economically unattractive since
a similar pipeline array layout project can be handled by
the embodiment disclosed in Figures 43-44 or by the
preferred embodiment of Figures 1-38 which permits a wide
range of laying depths.
ADDITIONAL MODIFICATIO~S
One of the advantages of the present invention is
that a pipe laying vessel of the Apache-type as described
in U.S. Patent No. 4,~30,421 to Springett, et al, desiyned
for only single pipeline layout can be utilized as the
base vessel for a conversion to a multi-reel pipe laying
vessel as described hereinO For such a conversion the
pivotal support ramp assembly, pipe bending radius
controller, the level wind assembly and the pipe
straightening, clamping, and guiding equipment are all
removed from the vessel's aft main deckl Thereafter, one
or two auxiliary reels are mounted for level winding and a
operational lines laying device such as the pipe take-off
assembly 24 is fitted onto the stern position 28 as shown
in Eigures 1-5 herein. The main reel utilized in an
Apache-type single pipeline vessel can be used with only
minor modification for increasing structural support and
the hydraulic powering/braking systems capacity. In this
manner an existing single pipeline vessel can be converted
into a plural operational lines laying vessel. Also, if
desired, the deck equipment can be switched back to the
pivotal support ramp type for laying single pipelines.
The process of converting a single pipe laying vessel to a
~266~S~
multi-reel pipe laying vessel and then the process of
reconversion to the ori~inal vessel are encompassed within
the present invention.
The laying devices of the various embodiments
have supporting means which are adapted for forming the
plurality of operational lines into initial
juxtaposition. The supporting means are the operational
lines support grooves in drum 26 of the vessel illustrated
in Figures 1-7, and the pipe support pads mounted on the
multiple track assemblies of the other illustrated
vessels. The initial juxtapositioning is such that either
a curved or a straight construction line passing through
such operational lines when it is positioned in a plane
perpendicular to the direction of motion of the
operational lines is also positioned substantially
transversely to the direction of vessel forward movement.
When the construction line is curved the operational lines
do not lie in a transverse plane, whereas when the
construction line is straight the operational lines are
juxtaposed in a planar arrangement. The initial
juxtaposition is usually maintained as the operational
lines array is moved through the subsequent straightenin~,
tensioning, and guiding devices. Thus while the plane in
which a curved construction line is positioned may change
its vertical inclination, the transverse positioning of
the construction line with respect to the forward motion
of the vessel remains substantially the same from the
initial juxtapositioning through the pipeline array
guiding device.
If desired, a pipeline angle measuring mechanism
can be fitted onto t~e pipe ta~e-off structure 30 below
the operating lines arra~ opening 368 of Figure 8. Such
- mechanisms are commercially available and can be
electronically linked to a co~puter read-out which is
maintained in the bridge of the control tower to permit
-.. ~ , - .
~L261~L56
- 69 -
monitoring of the water entry angle with respect to other
parameters of the pipe laying operation.
For certain operations- it is préferred to start
a pipeline layout in very deep water of 3,500 ft. or
greater at 87 water entry angle rather than utilizing a
slightly higher angle which can be accommodated by the
positioning of the pipe take-off assembly or laying device
24 of Figures 1-11. This start-out water entry angle is
then gradually decreased to angles used for the particular
pipeline in order to eliminate the possibility of buckling
of the rigid walled pipeline within the array. The full
limit of a 90 entry angle is rarely used.
Another variation in practice is to utilize a
subsea plough or jet sled for burying the operational
lines array on the bottom. A pulled plough such as
disclosed in U.S. Patent No. 4,410,297 can be employed for
this purpose. Another poss-ibility is to utilize a remote
controlled self-propelled plough. There are basically
three types of plough systems which are referred to as:
(1) a pre-trencher, which opens a trench line prior to the
laydown of the operational lines array, (2) a simultaneous
trencher, which lays the pipeline array in the trench
immediately after it is dug, and (3) a post trencher,
which buries the operational lines array under bottom
silt. All three types of plough systems can be used with
the vessel of the present invention.
In the vessel described herein, level windiny of
the auxiliary reels has been provided for. Such a winding
feature is primarily needed for spooling of the pipelines
- 30 onto their respective storage reels. If the fleet angles
between the storage reels and the laying device can be
held to within about 2 it is not necessary to provide for
level windiny during the unspooling and layiny out of the
lines stored thereon. If this limit can not be safely
maintained the level winding of the reels is employed
during unspooling. During the spooling operation the
. :,,, ' ..,,,,. ~ ,.,.,~,,
56
~ 70 -
plurality of lines are passed through the laying device 24
of Figures 1-38, but are contacted only at the top of the
drum 26. The laying device then functions as a feeding
device which permits level winding of the incoming array
during spooling. The lines can also be separately spooled
up on the storaye reels. While the main reel and the
auxiliary reels of the present invention have been
disclosed as vertical reels having horizontal positioned
axes it is also possible to mount one or more of these
reels on vertically disposed axes if desired.
While the vessels described herein are shown as
dynamically positioned ships it is also possible to mount
the storage reels and operational lines laying device on
to other t~pes of either selfpropelled, towed, or assisted
vessels. Such vessels can be ship shaped, barges with
configured or flat bottoms, semisubmersible vessels, or
small water area twin hull vessels known as SWATH ships.
In general, the operational lines laying device
shown in the preferred modifications disclosed and
illustrated with respect to Figures 1-38; and the vessels
illustrated in Figures 43-47 are preferred over the
pivotal support ramp vessel illustrated in Figures 39-42_
since the center of gravity of the pipe handling equipment
is constant which avoids the loss of metacentric height
for the vessel as the pipe handling equipment is raised
off the deck for deeper water layouts~
The invention may be embodied in other specific
orms without departing from the spirit or essential
characteristics thereof. The present embodiment is
therefore to be considered in all respects as illustrative
and not restrictive, the scope of the invention being
indicated by the appended claims rather than by the
foregoing description, and all changes which come within
the meaning and range of equivalency of the claims are
therefore intended to be embraced therein.
