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What is a Cable Laying Ship?
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A Cable Laying Ship is a sea going vessel designed to lay underwater communication cable networks.
Since, in today’s times, underwater cable connectivity has become more relevant and useful, the
importance and relevance of a Cable Laying Ship has also increased manifold.
Purpose of Cable Laying Ship
A Cable Laying Ship is created specifically to cater to the purpose of laying cable lines underwater. But at
the same time since cable laying work does not take place round-the-clock and throughout the year, a
Cable Laying Ship is also additionally used as research ships to monitor various happenings in the oceanic
and sea waters. A Cable Laying Ship is built with every modern gadget required to make the process of
laying the intricate lines of cable on the oceanic floor simpler. It is enabled with Dynamic Positioning and
Dynamic Tracking systems which pinpoint the exact location of the ship in the mid-ocean and lay the
underwater cable lines appropriately.
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Size of Cable Laying Ship
The torso of a Cable Laying Ship is huge because of the nature of the work it undertakes. Most of the cable
laying ships have a tonnage of over 11000 tons and are capable of laying not just one line of underwater
communicative cable lines but two-three lines in addition. And because it is so bulky in its torso, a cable
laying ship cannot be used for operations in shoals or shallow waters where there is a chance of land
merging with the waters because the shallowness of the water tends to curtail and hamper the movement
of the cable laying ship. Another specific feature that is unique to a Cable Laying Ship is that is built with
every damage control tool and equipment that might be necessary in case there is any damage done to the
underwater cable lines and contains both pneumatic – operated by air and hydraulic – operated by liquid
(oil or water) operating systems for the process of laying underwater cable liness
The size specification of a Cable Laying Ship depends on the depth of the ocean floor where it is required
to be positioning the cable lines. If the depth of the ocean bed or floor is more, then the size of the ship is
bigger and huger, whereas if the depth of the ocean bed or floor is not much, then the Cable Laying Ship’s
size tends to be smaller. However, it has to be noted that whether smaller or huger, the size of a cable
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laying ship many times bigger than that of a normal ship because of the extensive nature of the ship’s
purpose.
In today’s times, more than overhead cable networking, underwater cable lines have far more reachability
and penetrability. The underwater cable lines do not get much affected by natural calamities unlike their
land counterparts which get easily affected by occurrences like rain or snow. Furthermore, since
underwater cable lines are far below in the deepest part of the ocean, they can be laid uninterrupted over a
long length unlike land cable lines which have to face a lot of issues pertaining to the distance of the cable
and so and so forth.
Conclusion
Because laying an underwater cable line is so different but practical in the contemporary world, the work
and the purpose of a Cable Laying Ship becomes very helpful to the world. Like various channels which
help to fulfil the many necessities of man’s ever-growing world, the Cable Laying Ship is yet another brilliantcreation by man, created just to solve his communication and networking problems in a completely different
way.
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What is a Cable Laying Ship?
Communication technology has advanced drastically since last few
decades and eorts are continuously being made to make the world asmaller place. Cables are the life line of any kind of eective globalcommunication. Countries and continents around the globe are connectedusing cables. But how?
Introduction
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Providing eective and faster communication is a grave problem thatevery country faces today. The need of the situation demands a mode ofcommunication that is not only faster and eective but also reliable andcost eective. The world is getting smaller day by day and there is a direneed to break the geographical shackles by building up a durable
communication network. It is for this reason that networking cables are ingreat demand. Telecommunication companies are crisscrossing the oceanbeds with thousands
of kilometers long optical ber cables laid over thousands of nautical
miles! connecting countries and continents. These cables provide high
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speed broadband connectivity! a faster and a better way forcommunication.
These cables! unlike satellites can accommodate heavy tra"c withouttransmission delays. They are also not aected by the land based natural
calamities that have been the reason for destruction of manycommunication systems. But laying these cables across the ocean #oors isnot an easy task. $ot only is the task time consuming and e%pensive but italso causes a threat to the marine life.
Cable laying ships are used to lay cables across the depths ofocean #oors. They have their own propulsion system. The si&e of theship depends on the depth at which the cables are to be laid. 'igher thedepths! bigger is the ship. (o )ust read further to know more about thisinteresting type of ship.
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Construction of Cable Laying Ships
*ll the cable laying ships have +ynamic positioning and +ynamic trackingsystems on board. Cables are to be laid strategically and for thesereasons +P and +T systems are used. *ll these ships are generally large insi&e and cannot be used in shallow waters. * ship can lay one or twocables simultaneously on the ocean #oor. In case the distance to becovered is greater than a single cable! the ships have a provision to )oinmultiple cables. *ll these ships are also provided with repairingfacilities for rectifying broken cables.
*ll the cables are stored in huge holding tanks that spools out the cableswith the help of a device! as the ship moves forward. ,a%imum of theseships do not work as a cable laying ship through out the year.*part fromcable laying! they are also used as research or surveying vessels.
Working
Cable laying ships have all the facilities that any other type of ship has.*part from that ! the cable laying machine pulls the cables out of the
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holding chambers with the help of a deployment e-uipment. The cablelaying machine consists of a drum suspended from a crane which rolls thecable around it and lays it on the sea #oor with the help of slots made inthe ships astern. The drum operation system can be pneumatic orhydraulic depending on the si&e and weight of the cables.
/hen the cables reach the ocean #oor! they are buried in the sea bed withthe help of a trenching system. This method is used for cable laying atgreater depths. In case of shallow waters! directional drilling method isused.
Cable laying ship
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CS Cable Innovator at anchor in Astoria, Oregon, showing a modern design without bow sheaves.
CS Hooper , the world's first purpose-built cable-laying ship, built byC. Mitchell Co of !ewcastle-upon-"yne in #$%&, renamed
CS Silvertownin #$$#
CS Dependable at Astoria, Oregon, a modern stern sheave design.
A cable layer or cable ship is a deep-sea vessel designed and used to lay underwater
cables for telecommunications, electric power transmission, or other purposes. Cable ships are
distinguished by large cable sheaves#( for guiding cable over bow or stern or both. )ow sheaves,*( some very large, were characteristic of all cable ships in the past, but newer ships are tending
toward having stern sheaves only, as seen in the photo of CS Cable Innovator at the +ort of
Astoria on this page. "he names of cable ships are often preceded by C.S. as in CS Long
Lines.&(
"he first transatlantic telegraph cable was laid by cable layers from #$%$. /t briefly enabled
telecommunication between 0urope and !orth America before misuse resulted in failure of the
line. /n #$11 the SS Great Eastern successfully laid two transatlantic cables, securing futurecommunication between the continents.
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Modern cable ships
Modern cable ships differ greatly from their predecessors. "here are two main types of cable
ships2 cable repair ships and cable-laying ships. Cable repair ships, li3e the 4apanese Tsugaru
Maru, tend to be smaller and more manuverable5 they are capable of laying cable, but their
primary 6ob is fi7ing or repairing bro3en sections of cable. A cable-laying ship, li3e the Long Lines,
is designed to lay new cables. Such ships are bigger than repair ships and less maneuverable5
their cable storage drums are also larger and are set in parallel so one drum can feed into
another, allowing them to lay cable much faster. "hese ships are also generally e8uipped with a
liner cable engine 9:C0; that helps them lay cable 8uic3ly.
"he newest design of cable layers, though, is a combination of cable-laying and repair ships. An
e7ample is the <S!S =eus, the only <.S. naval cable layer>repair ship. "he Zeus uses two diesel
electric engines that produce ??? horsepower each and can carry her up to # 3nots 9about *
miles per hour;, and she can lay about #??? miles of telecommunications cable to a depth of
@??? feet. "he purpose of the Zeus was to be a cable ship that could do anything re8uired of it,so the ship was built to be able to lay and retrieve cable from either the bow or the stern with
ease. "his design was similar to that of the first cable ship, the Great Eastern. "he Zeus was built
to be as maneuverable as possible so that it could fulfill both roles2 as a cable layer or a cable
repair ship. (
Equipment
"o ensure that cable is laid and retrieved properly, specially designed e8uipment must be used.
Bifferent e8uipment is used on cable laying ships depending on what their 6ob re8uires. /n order
to retrieve damaged or mislaid cable, a grapple system is used to gather cable from the oceanfloor. "here are several types of grapples, each with certain advantages or disadvantages. "hese
grapples are attached to the vessel via a grapple rope, originally a mi7 of steel and manila lines,
but now made from synthetic materials. "his ensures that the line is strong, yet can fle7 and
strain under the weight of the grapple. "he line is pulled up by reversing the :iner Cable 0ngine
used to lay the cable. (
"he most common laying engine in use is the :iner Cable 0ngine 9:C0;. "he :C0 is used to
feed the cable down to the ocean floor, but this device can also be reversed and used to bring
bac3 up cable needing repair. "hese engines can feed $?? feet of cable a minute. owever ships
are limited to a speed of $ 3nots while laying cable to ensure the cable lies on the sea floor
properly and to compensate for any small ad6ustments in course that might affect the cables'position, which must be carefully mapped so that they can be found again if they need to be
repaired. :iner Cable 0ngines are also e8uipped with a bra3e system that allows the flow of
cable to be controlled or stopped if a problem arises. A common system used is a fleeting drum,
a mechanical drum fitted with eoduldes 9raised surfaces on the drum face; that help slow and
guide the cable into the :C0. 1( Cable ships also use DplowsE that are suspended under the
vessel. "hese plows use 6ets of high pressure water to bury cable & feet under the sea floor,
which prevents fishing vessels from snagging cables as thrall their nets. %(
M"S$( Monarch 9renamed CS Sentinel #& October #@%?;#( completed the first transatlantic
telephone cable, "A"-# in #@1@( from Scotland to !ova Scotia for )ritain's Feneral +ost
Office 9F+O;.
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Cable Innovator -
At #?,%dwt, the Cable /nnovator is the world's largest vessel of its 3ind, specifically
designed for laying fibre optic cable. "he vessel was built in #@@ by Gvaerner Masa
of Hinland.
All cable-laying operations are carried out over the stern, so the ship travels much
faster to the site and is not slowed down by conventional bow sheaves. /t can
operate in e7treme weather while providing optimum protection for all cable-handling
operations. /t is e8uipped to deploy a remotely operated vehicle 9IOJ;.
Design
"he Cable /nnovator cable handling e8uipment centres on a *#-wheel pair linear
cable engine 9:C0; and a m diameter electrically driven cable drum with fi7ed-angle
fleeting rings and fleeting 3nives that are primarily responsible for controlling the
cable lay. "he cable drum has ,$%mK ma7imum cable volume and $,??t ma7imum
load.
"he e8uipment also comprises a four-pair BO>) unit with an hydraulically activated
traversing cable deflector and a two-dec3 head-mounted single-wheel pair of cable
transporters, capable of traversing onto either cable line. "he Cable /nnovator has a
conventional set of cable wor3ing instrumentation and two computerised 9dual
redundant; cable instrumentation systems.
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"here is a &t SL: 9sea state ; A-frame with wor3ing arc from outboard to
inboard to handle the plough used to bury the cable in the seabed. "here are two #?t
SL: buoy>stores cranes aft, one t SL: stores crane forward and one *t SL:
stores crane forward.
"he normal endurance of the vessel at sea is * days, but this can be e7tended to
appro7imately 1? days through logistical support.
Propulsion
At #?,%dwt, the Cable /nnovator is the world's largest vessel of its 3ind, specifically
designed for laying fibre optic cable.
"he vessel's power comes from five LNrtsilN Jasa diesel engines, three @I&*0 units
of &,13L each driving a ,#1?3JA>1? l&.&3J A)) AC generator, and two 1I**>
*1 machines of @%3L 9#,#?3JA at #&.&3J;, which provides a total installed power
of #*.$ML.
A total of .&ML of power is available at the vessel's single main GaMeLa fi7ed
pitch propeller, which is powered by two A)) variable speed, reversing AC electric
propulsion motors, each rated at *,%??3L. "he vessel has no rudder but there are
two #*t GaMeLa tunnel thrusters located at the stern, each rated at @??3L and able
to provide about *t of transverse thrust. A Lhite Fill 6et thruster of *,???3L and a
tunnel thruster of #,*??3L are installed at the bow.
Automation and control
"he Cegelec @?* duple7 system allows the vessel to be controlled in various modes
from a manual 6oystic3 mode to a B+ mode where the position and heading are
automatically controlled. /n addition, the system offers transit modes, the vessel
being controlled either to maintain a set heading or to follow a specific trac3.
"he F0M$?>?? and S+AIC computer located in the master B+S console provide
the control and interfacing to the thrusters, main propulsion motors, position
measurement and navigational systems, power systems, plough, event monitoring
and remote 6oystic3 stations. A further F0MS?>?? independent 6oystic3 system also
provides interfaces to the thrusters and the steerable nole and gyrocompass.
"he normal endurance of the vessel at sea is * days.
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A full suite of duplicated modern navigational, shallow and deep water bathymetry
recording and radio e8uipment are installed and upgraded to ensure a state-of-the-
art performance, including multiple F+S and SA"COM facilities. "he +osition
Measuring 08uipment 9+M0; features a hydro-acoustic system with super shore
baseline, BF+S and two taut wires.
"hese supplement the gyrocompass, vertical reference unit, anemometer and
Artemis systems. +ooling the data together from all of these elements secures the
most accurate position fi7.
"he system can also display and ta3e account of plough tow cable tension when thevessel is engaged in cable laying, initiating an alarm if the cable tension rises too
high or automatically slowing the vessel's speed.
Onboard communication systems include /nmarsat ) C and Jsat G< )and.
Accommodation
"he ship has $? cabins, of which * are officer cabins, &1 are crew cabins and two
are representative suites. Office suites and conference facilities are also available.
At !"!#!dwt $#"%%>'" the Cable Innovator is the world(s largest vessel o) its *ind" speci)icall+ designed )or la+ing
)ibre optic cable,
Cable Innovator is #-. in length and %#. in breadth, It has a )ull+ loaded dra)t o) /,-.,