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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 $#"%%&gt'" 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) /,-.,