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<ul><li><p>Acknowledgements</p><p>1 wish to lhank the many firms, organisations and individuals who have providedme with assistance and malcrial during the writing of lhis book.</p><p>For guidance provided in their specialist areas I would like (0 thankMe W. Cole, Welding Manager and Mr I. Waugh, Ship Manager, both of SwanHunter Shipbuilders.</p><p>To the firm of Swan Hunter Shipbuilders, now a member of British Ship-builders, I wish 10 extend my thanks for their permission to use drawings andinformation based on their current shipbuilding practices.</p><p>The following firms and organisations contributed drawings and informationfor various sections of this hook, for which I thank them:</p><p>AGA Welding LtdAustin and Pickergill LtdBlohm and Voss, A.G.DOC CUlling MachinesBrown Brothers &amp; Co. LtdCammcll Laird ShipbuildersCape Boards and Panels LtdClarke Chapman LtdDookin and Co. LtdF.A. Hughes and Co. LtdFlakt Ltd (S.F. Review)Glacier Metal Co. LtdHempel's Marine PaintsHugh Smith (Glasgow) LtdInternational Maritime OrganisatonUoyd's Register of Shipping</p><p>MacGregor Centrex LtdMoss Rosenberg Verft, AS.Odense Steel Shipyard ltdPhilips Welding IndustriesPhoceenne Sous-Marine, S.A.Power Blast ltdRockwool Co. (UK) ltdSigma Coatings LtdStone Manganese Marine LIdStone VickersStrommen Staal, A.S.Taylor Pallister and Co. ltdThe DeVilbiss Co_ LtdThe Ntn'aJ ArchitectVoith GmbHWilson Walton International ltd</p><p>Contents</p><p>The ship - its functions, featutes and types</p><p>2 Ship stresses and shipbuilding materials</p><p>3 Shipbuilding</p><p>4 Welding and cutting processes</p><p>5 Major structural itemsA Keel and bottom construction 72B Shell plating, framing systems and decks 77C Bulkheads and pillars 85D Fore end construction 92E Aft end construction 101F Superstructures and accommodation 116</p><p>6 Minor structural items</p><p>7 Outfit</p><p>8 Oil tankers, liquefied gas carriers and bulk carriers</p><p>9 Ventilation</p><p>10 Organisations and regulations</p><p>II Corrosion and its prevention</p><p>12 Surveys and maintenance</p><p>13 Principal ship dimensions and glossary of terms</p><p>Index</p><p>13</p><p>'72</p><p>125</p><p>134</p><p>165</p><p>185</p><p>197</p><p>213</p><p>223</p><p>229</p><p>235</p></li><li><p>1The Ship- its Functions,Features and Types</p><p>Merchant ships exist 10 carry cargoes across the waterways of the world safely,speedily and economically. Since a large pan of the world's surface.approximately threefifths. is covered by water. it is reasonable 10 consider thatthe merchant ship will continue to perform its funclion for many centuries 10come. The worldwide nalure of this function involves the ship, its cargo and itscrew in many aspects of inll~rnational life. Some It:atures of this internationaltransportation. such as weather and climatic changes, availability of cargo-handling facilities and international regulations. will be considered in laterchapters.</p><p>The ship, in its various forms. has ~volved to accomplish its functiondqxnding upon three main factors - the type of cargo carried. the type ofconstruction and materials used. and the area of operation.</p><p>Three principal cargo-carrying Iypes of ship exisl loday: Ihe general cargoftSSel, !he lanker and the passen~r ve~1. The general cargo ship functionstoday as a general carrier and also, in several particular forms, for unit-based orunitised cargo carrying. Examples include container ships, pallet ships and 'rollon, roll-ofr ships. The tanker has its spedalised forms for the carria~ of crudeoil, refined oil products, liquefied gases, etc. The passenger ship includes,senerally speaking, the cruise liner and some ferries.</p><p>The type of construction will affect the cargo carried and, in some generallyinternal aspects, !he characteristics of !he ship. The principal types ofconstruction refer to the framing arrangement for stiffening the outer shellplating, the three types being longitudinal, transverse and combined framing. Theuse of mild steel, special steels, aluminium and other materials also influencesthe characteristics of a ship. General cargo ships are usually of transverse orCOmbined framing construction using mild steel sections and plating. Mosttankers employ longitudinal or combined framing systems and the larger vesselsutilise high tensile steels in their construction. Passenger ships, with their largeareas of superstructure, employ lighter metals and alloys such as aluminium toreduce the weight of the upper regions of the ship.</p><p>The area of trade, the cruising ra.nge, the climatic extremes experienced, mustall be borne in mind in the design of a particular ship. Ocean-going vesselsreqUire several tanks for fresh water and oil fuel storage. Stability and trimIrrangemenu musl be satisfactory for the weather conditions prevailing in the</p></li><li><p>3'~~ ~ci J:!. ~0 0~</p><p>'@] ,5oj:! '-z1,'-</p><p>0z</p><p>~-- ... -</p><p>'-</p><p>~ 1'</p><p>'-</p><p>~</p><p>__ i __</p><p>,</p><p>cdr--;-L{,L ,0,.</p><p>~l</p><p>~r lr</p><p>The tanker is used to carry bulk liquid cargoes, the most common type being Iheoil tanker. Many other liquids are carried in tankers and specially constructedvessels are used for chemicals, liquefied petroleum gas. liquefied natural gas. etc.</p><p>The oil tanker has fhe cargo</p></li><li>Th~ Ship _ Itt FUllction!. Featu'S and Types 7,c</li><li><p>W''J~~10,11</p><p>c_-,</p><p>~.twnetblilasl)</p><p>.Iugtl1000000tud.M</p><p>bulk't~</p><p>Oou~bOnom I~klooll'.el 01' '~ bllIBfI</p><p>III_...</p><p>-II</p><p>Ilbl</p><p>1.1</p><p>c</p><p>V(;enll't holdtoil 0/1 QO~1</p><p>I</p><p>w..~w.. I~twltBI twllBl 0</p><p>Wi', tankloill</p><p>Wit' blUast</p><p>Fixun J.J Tranrvn'St sntions: (tI} lxl/k curitr, fb} ort/oil CII,'</p><p>The ore/bulkfoil carrier has a cross-section similar to the general bulk. carriershown in FIgUre 1.4. The structure is, however, significantly stf</p></li><li><p>I</p><p>i. j'</p><p>~o i</p><p>'Z&lt; o l:!z&gt;</p><p>o</p><p>=--=-</p><p>,----,</p><p>- ----;.,--=-=-,~</p><p>-F--~---------</p><p>,z</p><p>&gt;</p><p>!'..</p><p>1]C</p><p>'.0</p><p>. .. -T, ' ,</p><p>, '- ;.-'-'-, ' , , ,I. J_J.r .,-,., , , , ,.. -l-.,., , , , ,</p><p>L~_.</p><p>r .,-.,-, I 1 I, I t I,- .,-10-</p><p>i ' , , I. I I , I~;; t..I. . _J.</p><p>'lj ,...,..,--. '__..i. ~' ~': 1~ ~ t-~i-i'!&lt; C ' I IcJ 0 L 1 _I. .l.:;J!-----r</p><p>r-' .,- .I ' , , ' , I.. J_~ __</p><p> , I1 I , IL_L-l.J</p><p>i</p><p>Container ships</p><p>The container ship is, as its name implies, designed for the carriage of containen.A container is a reusable box of 2435 mm by 2435 mm section, with lengthsof 6055, 9125 and 12190 mm. Containcrs arc in use for most general cargoes,and liquid--earrying versions also exist. In addition. refrigcrated models are inuse.</p><p>The cargo--earrying section of the ship is divided into several holds which havehatch openings the full width and length of the hold (Figure 1.6). The COntaincrsarc racked in special frameworks and stacked one upon the other within the holdspace. Cargo handling therefore consists only of vertical movement of the cargoin the hold. Containers can also be stachd on the hatch covers where a lowderuily cargo is carried. Special lashing arrangements exist for this purpose andthis deck cargo to SOme extent compensates for the loss of underdeck capaCity.</p><p>The various cargo holds are separated by a deep web-framed structure toprovide the ship with transverse strength. The ship section Outboard of theContainers on each side is a box-like arrangement of wing tanks which provideslongitudinal strength to the structure. These wing tanks may be utilised forwater ballast and can be arranged to COunter the heeling of the ship whendischarging containers. A double bottom is also fitted which adds to thelongitUdinal strength and provides additional ballast space.</p><p>Accommodation and machinery spaces are usually lOCated aft to provide themaximum length of fullbodied ship for container stowage. Cargo-handling gearis rarely fitted, as these ships travel between speciaUy equipped terminals forrapid loading and discharge_ Container ship sizes vary considerably withcontainer-earrying capacities from 100 to 2000 or more. As specialist carriersthey are designed for rapid transits and are high powered, high speed vesselswith speeds up to 30 knots. Somc of the larger vessels have triple-screwpropulsion arrangements.</p><p>Passenger ships</p><p>The passenger liner, or its modern equivalent the cruise liner, exists to provide ameans of luxuriow transport between interesting destinations, in pleasantclimates, for its human cargo. The passenger travelling in such a ship pays for,and expects, a SUperior standard of accommodation and leisure facilities. Largeamounts of superstructure are therefore an essential fealure of passenger ships.Several tiers of declo are fitted with large open lounges, ballrooms, swimmingpools and promenade areas (Figuu J. 7).</p><p>AestheticaJly pleasing lines arc evident with Usually well.raked clipper-typebows and unusual funnel shapes. Stabilisers are fitted to reduce rolling and bowthrust devices arc employed for improved manoeuvrability. large passengerliners arc rare, the moderate-sized cruise liner of 12000 tonnes displacementnow being the more prevalent. Passenger-carrying capacity is around 600, withspeeds in the region of 22 knots.</p><p>10 Thf! Ship - Its Functions. F~Qtuns lUTd Typesit is sometimf!S fitted. Combination carriers handling oil cargoes have their owncargo pumps, piping systems. f!tc., for discharging oil. Bulk carriers are dealtwith in more detail in Chapter 8. Deadweight capacities range from small to150000 tonnes depending upon type of cargo, etc. Speeds arc in the range of12-J6 knots.</p></li><li><p>12</p><p>RoilingP'ICh,'iI</p><p>Fif(Ure 1.1 Ship mOl'l!ml!nl - thl! silt dl!grl!~ offreedom</p><p>The forces may initially be classified as static and dynamic, Static forces are dueto the differences in weight and buoyancy which occur at various points alongthe length of the ship. Dynamic forces result from the ship's motion in the seaand the action of the wind and waves. A ship is free to move with six degrees offreedom - three linear and three rotational. These motions are described by theterms Ylown in Figure 2. J.</p><p>These static and dynamic forces create longitudinal, transverse and localstres.ses in the ship's structure. Longitudinal stresses are greatest in magnitudeand result in bending of the ship along its length.</p><p>13</p><p>The ship at sea or lying in still water is being constant!)' subjected 0 :I widevariety of sueues and strains. which result from the action of (orces fromoutside and within the ship. Forces within the ship result from structural weight.cargo. machinery weight and the ef(ects of operating machinery. Exterior forcesinclude the hydrostatic pressure of the water on the hull and the action of thewind and waves. The ship must at all times be able to resist and withstand thesemesses and strains throughout its struClUre. II mUSI therefore be conslrucledin a manner, and of such materials, that will provide the necessary strength. Theship must also be able to function efficiently as a cargo-carrying vessel.</p><p>The various forces acting on a ship are constantly varying as to their degreeand frequency. For simplicity. however. they will be considered individually andthe particular measures adopted to counter each type of force will be outlined.</p><p>2</p><p>Ship Stresses andShipbuilding Materials</p><p>-. ~</p><p>f-</p><p>I/</p><p>/</p><p>f-</p><p>I--</p><p>,..-_c-</p><p>- f-f--</p><p>(</p><p>--</p><p>h</p><p>UJ</p><p>With plan approval the ordering of equipment, machinery, steel section andplate, etc., will begin and the plans will be issued to the various productiondepartments in the shipyard. The classification society, the owners and theirrepresentatives in the shipyard also receive copies of the plans.</p><p>During the manufacturing processes, as a result of problems encountered,feedback from previous designs, modifications reque5ted by the owner, etc.,amendments may be made to plans. A system of plan recall, replacement ormodification in the production departments must be available. This ensuresthat any future ships in a series do not carl)' the same faults and that co'ectiveaction has been taken.</p><p>The fundamental design plans and basic constructional details must all receiveclassification society approval and, of course, the shipowner's approval. Unwuaiaspects of design and innovations in coostructional methods will receive specialattention, as will any depanures from standard practice. Progress is not hinderedby the classification societies, whose main concern is the production of a soundand safe structure.</p><p>The shipowner will normally have clearly indicated his requirements from thedesign inception and his approval of plans is usually straightforward. Most largeshipowning companie5 have a technical staff who utilise their practicalexperience in developing as near perfect and functional a design as possible.</p><p>Steel ordering</p><p>Plan approval</p><p>34 Shipbuilding</p><p>Once fairtd. the final lines plan is prtpartd and a tablt of offsets is compiledfor usc in producing the ship's plates and frames.</p><p>The traditional practice of drawing plans according to structural areas suchas the shell, the deck, the double-bottom framing, elC., is inconvenient in manycases since the ship is nowadays buill up of large prefabricated units. A unit mayconsist of shell plating, some framing and part of a deck. An expansion of aship's shell is given in Figure 3.2, sho...ing the positions of the various units.Plans are therefore drawn in relation to units and contain all tht informationrequired 10 build a particular unit. A number of traditional plans arc stillproduced for classification society purposes, future maintenance and reference,but without the wealth of manufaclUring information which is only needed onthe unit plans.</p><p>The planning and production control departments require drawinginformation to compile charts for monitoring progreSS. compiling programmes,producing programmes for material delivery, parts production and assemblyand finally unit production and erection.</p><p>Plan issue</p><p>The ordering of steel to ensure availability in line with programmed require-menU is essential. It must therefore begin at the earliest opportunity,</p></li><li><p>36 Shipbuilding 37</p><p>~~.;:</p><p>, ~</p><p>~ ~,v ~;</p><p>~,-~,~,</p><p>-g~</p><p>~</p></li><li><p>38 Shipbuilding</p><p>. The i~pul data for the machine is initially produced from drawings and offsetInformal.lon. !he various parIS to be produced 3rc programmed and then coded</p><p>~r deSCribed In numeri~~ terms. Punched card, punched tape or magnetic tapeIS then p~oduced contalrung I~e numerical data. The card or tape information isthen fe~ mlo a compuler neSlang program. The various pariS are then 'nested' orecono~lcally fi.'ed into a standard plate size (Figurr 3.1). A final punched ormagnetIC tape IS. produ~ed Which. is. used for the operation of the numericallycontrolled machine. ThIS process IS illustrated by a simple now chart in Figu~4. rr</p><p>Shipbuilding 39</p><p>sler before, during and after the various pro~esses in shipbuildin~ utilisesuan handling appliances. such as overhead travelling cranes, vacuum 11ft cranes~l8JIetic cranes, roller conveyors, fork.li~t equipment, etc..o The various steel parts in plate and sectlon form are now Jomed to~ether by</p><p>lding to produce subassemblies, assemblies and units. A subassembly IS several~ of steel making up a tw</p></li><li><p>40 Shipbu.ildingShipbuilding 41</p><p>/,-_-1</p><p>--r-'-</p><p>--.,.</p><p>-._--</p><p>FiliUrc 1.8 lJmr</p><p>l(}ng',tud'ln~1bulk'~6rl</p><p>Inn~r bottom plating</p><p>A typical m.achine will first water-wasb then heatdry the plates hefore descalil1g.The plates are then simultaneously shot-blasted both siJ-e-s with metallic abrasive.The pl..</p></li></ul>