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Unit1SHIPSANDSHIPSTERMSSHIPDESIGNANDCONSTRUCTION(generalintroduction)Basictermshullsuperstructuremachinerysternbowamidshipsbeamdeckengineroompropellershaftbowthrusterrudderbulbousbowhold1Amulti-purposevessel2Anoiltanker3Acontainervessel4Aroll-on/roll-ofship5bulkcarrier-elevation/profile6Abulkcarrier–upper/maindeckplanShipsarelarge,complexvehicleswhichmustbeself-sustainingintheirenvironmentforlongperiodswithahighdegreeofreliability.Ashipistheproductofthreemainareasofskill,thoseofthenavalarchitect,thenavigatingofficer(deckofficer)andthemarineengineer(engineeringofficer).Thenavalarchitectisconcernedwiththehull,itsconstruction,form,habitabilityandabilitytoendureitsenvironment.Thenavigatingofficerisresponsibleforsafenavigationoftheship,anditscargooperations.Themarineengineerisresponsibleforthevarioussystemswhichpropelandoperatetheship.Morespecifically,thismeansthemachineryrequiredforpropulsion,steering,anchoringandshipsecuring,cargohandling,airconditioning,powergenerationanditsdistribution.Therearetwomainpartsofaship:thehullandthemachinery.Thehullistheactualshelloftheshipincludinghersuperstructure,Themachineryincludesnotonlythemainenginesrequiredtodriveherbutalsotheauxiliarymachinery(boilers,generators,etc.)usedformanoeuvringpurposes,steering,mooring,cargohandlingandforvariousotherservices,e.g.theelectricalinstallations,winchesandrefrigeratingplant.Therearportionoftheshipiscalledtheafterendorstern.Whenmovingsternfirst,thevesselissaidtobemovingastern.Thefrontportionoftheshipiscalledtheforeend,whilsttheextremeforwardendiscalledthebow.Whenmovingbowfirst,thevesselissaidtobemovingahead.Foreandaftaregenerallyusedfordirectionalpurposes.Theareabetweentheforwardandaftportionsofthevesseliscalledamidships.Themaximumbreadthofthevessel,whichisfoundintheamidshipsbody,isknownasthebeam.lengthoverallbeambowmidshipsbridgesternManymoderncargoandpassengerlinershaveatransversepropulsionunitorbowthrusterinthebows.Itspurposeistogivegreatermanoeuvrabilityinconfinedwaters,e.g.ports,andsoreduceoreliminatetheneedfortugs.starboardbowstarboardbeamstarboardquarterdeadaheaddeadasternportbowportbeamportquarterTherudder,whichenablesthevesseltomaintainhercourse,issituatedrightaft.Thebulbousbowcanimprovepassengerandcrewcomfort,asitcanreducepitchinginheavyseasandhasbeenprovidedintankers,bulkcarriers,andmoderncargolinerstoincreasespeedwheninballast.Themoderntendencyistohavelargeunobstructedholdswithmechanicallyoperatedhatchcovers,bothforthespeedyhandlingofcargo,andtoreduceturn-roundtimetoaminimum.7Generalarrangementsplan–abulkcarrierAship'sactualdesignandnumberofdecksdependonthetradeinwhichtheshipwillply.Atramp,carryingshipmentsofcoalorore,willbeasingledeckvesselwithlargeunobstructedhatchestofacilitateloadinganddischarge.Acargolinercarryingavarietyofcargoinrelativelysmallconsignmentswouldhave'tweendeckstofacilitatestowage.Ifsuchavesselalsoconveyedwoodandothercommoditiesofhighstowagefactor,ashelterdeckwouldbeprovided.Additionally,containershipsareequippedwithspeciallydesignedholdswithcellsorslotstofacilitatespeedycontainerhandlingusingshore-basedliftinggear.MachineryThreeprincipaltypesofmachineryinstallationaretobefoundatseatoday.Theirindividualcharacteristicschangewithtechnologicaladvancesandimprovementsandeconomicfactorssuchasthechangeinoilprices.Thethreelayoutsinvolvetheship’spropulsionmachineryusingdirect-coupledslow-speeddieselengines(themainengine),medium-speeddieselswithagearbox,andthesteamturbinewithagearboxdrivetothepropeller.Apropeller,inordertooperateefficiently,mustrotateatarelativelylowspeed.Thus,regardlessoftherotationalspeedoftheprimemover,thepropellershaftmustrotateatabout80to100rev/min.Theslow-speeddieselenginerotatesatthislowspeedandthecrankshaftisthusdirectlycoupledtothepropellershafting.Themedium-speeddieselengineoperatesintherange250—750rev/minandcannotthereforebedirectlycoupledtothepropellershaft.Agearboxisusedtoprovidealow-speeddriveforthepropellershaft.Thesteamturbinerotatesataveryhighspeed,intheorderof6000rev/min.Again,agearboxmustbeusedtoprovidealow-speeddriveforthepropellershaft.A.Comprehension&vocabularyA.1Findthepartsofthereadingtextwhichprovideanswerstothefollowingquestions:1.Whatdothetwomainpartsoftheshipinclude?2.Whatarethetwoextremeendsofashipcalled?3.Definethelocationandfunctionofthefollowingshipparts:bow,stern,funnel,mainmast,stem,sternpost,shipboardcrane,doublebottom,engineroom,rudder,bulbousbow,bowthruster,hatchcover,free-falllifeboat,forecastle,poopdeck,bridge,wheelhouse,forepeak,afterpeak4.Whichtypesofmachineryarehousedintheengineroom?5.Wherearetheanchorsandwindlassesplaced?A.2Completethefollowingsentences:1.Thehullincludesboth_______________.2.Theship'smachineryincludes______________.3.Whenmovingbowfirst,theship_________________andshe_________________whenshemovessternfirst.4.Themidshipportionoftheshipissituatedbetween________.5.Thebeamis_______________.6.Therudderisdesignedto___________________.7.Thebowthrustergivestheship_______________.8.Modernshipholdsareequippedwithmechanicallyoperatedhatchcoversto________