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EnglishforMarineEngineersByLIPinyouShanghaiMaritimeUniversityIntroductiontotheCourseThefirst“namecard”O(jiān)neofthemostcomprehensivecoursesOneoftheMSAexaminationcoursesContentsListening&SpeakingReading:mainengine;auxiliarymachineries;electricalequipment&automation;marineengineeringmanagement;internationalconventions&codesWriting:engineroomlogbook;repairlist;orderlist;accidentreport;operatingproceduresforkeyequipmentExaminationChoices:60%Readingcomprehension:20%Writing:20%BasicVocabulary&Terms(1).Shiptypes(2).Officers&Ratings(3).EngineTelegraph&SteeringOrders(4).MarinePowerPlants(5).MainEngine(6).AuxiliaryMachinery(7).Valves&Pumps(8).Tools&Meters(9).MarineOils(1).Shiptypes

CategoryClassTypeTankerOiltankerGastankerChemicaltankerOBOCrude(oil)CarrierVeryLargeCrudeCarrierUltraLargeCrudeCarrierProductTankerLiquefiedNaturalGascarrierLiquefiedPetroleumGascarrierOil/Bulk/OrecarrierCCVLCCULCCLNGLPGOBOBulkcarrierBulkcarrierContainershipContainershipGeneralcargoshipGeneralcargoCoasterReeferReeferRefrigeratedcargovesselPassengershipFerryCruisevessel(2).Officers&RatingsOfficersRatingsDeckDepartmentCaptain(Master)C/O;2nd/O;3rd/OBosun;helmsman;Ablebodiedseaman;Ordinaryseaman;CarpenterEngineDepartmentC/E2nd/E;3rd/E;4th/E;ETOChiefmotorman;Pumpman;oiler;electricianBusinessDeparmentPoliticalcommissar;doctor;chiefpurser;Chiefcook;secondcook;steward(3).EngineTelegraphStandbyengineDeadslowahead/asternSlowahead/asternHalfahead/asternFullahead/asternStopengineFinishedwithengine(3).SteeringOrdersMidships正舵Port/starboardfive左、右舵10度Port/starboardtenPort/starboardfifteenPort/starboardtwentyHard-a-port/starboardSteadyFinishedwithwheel完舵(4).MarinePowerPlant

Marinedieselengine

船用柴油機(jī)Marinesteamturbine

船用蒸汽輪機(jī)Marinegasturbine船用燃?xì)廨啓C(jī)Marinenuclearplant核動(dòng)力(5).MainEnginetwo-strokemarinedieselenginefour-strokemarinedieselenginelowspeeddieselenginemediumspeeddieselenginehighspeeddieselengineWorkingcycleSuctionstrokeCompressionstrokeExpansion(explosion;power;firing)strokeExhauststrokeWorkingcycleof4-strokeengineWorkingcycleof2-strokeengineEnginepartsFixedparts:bed-plate;frame;cylinder;etc.Movingparts:piston;connectingrod;crankshaft;etc.Cylindercylinderhead汽缸頭cylinderblock汽缸體cylinderliner汽缸蓋coolingwaterspace冷卻水空間coolingwaterjacket冷卻水套Pistonpistoncrown活塞頭pistonskirt活塞裙pistonpin活塞銷pistonring活塞環(huán)pistonringgroove活塞環(huán)槽pistoncoolingspace活塞冷卻空間pistonrod活塞桿（十字頭）Cross-headcross-headpin十字頭銷cross-headbearingcross-headslipper(guideshoe)滑塊cross-headguideplate導(dǎo)板top(small)endbearing大端/小端軸承Crankshaftcrankshaftbearing曲柄軸承crankpin曲柄銷crankjournal曲軸頸crankweb曲軸臂crankshaftdeflection曲柄臂開閉量big(bottom)endbearing大（底部）端軸承Shaftingthrustshaft推力軸intermediateshaft中間軸tailshaft尾軸thrustbearing推力軸承thrustpad推力塊sterntubebearing尾軸管軸承PropellerBoss(hub)漿骨Blades(3~5)槳葉Left-handedpropeller左旋槳Right-handedpropellerFixedpitchpropeller(FPP)定距槳Controllable(Variable)pitchpropeller(CPP/VPP)可控螺距槳FixedPartsbed-plate機(jī)座Frame機(jī)架Crankcase曲軸箱crankcasedoor曲軸箱檢查孔蓋tie-bolt(tie-rod,throughbolt)貫穿螺栓Scavenginguniflowscavenging直流掃氣crossscavenging橫流掃氣loopscavenging回流掃氣scavengingport(inletport)掃氣口exhaustport(outletport)排氣口Turbo-chargingexhaustgasturbocharger廢氣渦輪增壓器Turbine渦輪Compressor壓縮機(jī)emergencyblower應(yīng)急鼓風(fēng)機(jī)constantpressuresystem定壓系統(tǒng)pulsesystem脈沖系統(tǒng)PowersystemsFueloilsystem燃油系統(tǒng)Lubricatingoilsystem滑油系統(tǒng)Coolingwatersystem冷卻水系統(tǒng)Compressedairsystem壓縮空氣系統(tǒng)Fueloilsystemdoublebottomtank雙層底艙settlingtank沉淀柜dailyservicetank日用柜fuelpump燃油高壓泵fuelinjector燃油噴射器fuelinjectioncam噴射凸輪LubricatingoilsystemSump油底殼cylinderlubricator氣缸潤(rùn)滑器telescopicpipe伸縮管oilfilter燃油濾器draintank放殘柜Coolingwatersystemopeningcoolingsystem開式冷卻系統(tǒng)closedcoolingsystem閉式冷卻系統(tǒng)centralcoolingsystem中央冷卻系統(tǒng)expansiontank(headtank)膨脹水箱Compressedairsystemaircompressor壓縮空氣機(jī)airbottle(receiver,reservoir)氣瓶startingairvalve啟動(dòng)空氣閥startingairdistributor啟動(dòng)空氣分配器aircooler空氣冷卻器scavengingreceiver掃氣箱ControlsystemGovernor調(diào)速器reversingdevice換向裝置reversingservomotorcontrolstand控制臺(tái)controlroom控制室UMS(UnattendedMachinerySpace)無(wú)人機(jī)艙(6).AuxiliaryMachinerymarineboiler船舶鍋爐refrigeratingplant制冷裝置steeringgear舵機(jī)oilseparator分油機(jī)anti-pollutionequipment防污設(shè)備deckmachinery甲板機(jī)械Marineboilerdonkey(auxiliary)boiler輔鍋爐exhaustgasboiler廢氣鍋爐watertubeboiler水管鍋爐firetubeboiler煙管鍋爐Furnace爐膛oilburner燃油器Refrigeratingplantdomesticrefrigerator家用電冰箱refrigeratingcompressor制冷壓縮機(jī)Condenser冷凝器thermostaticexpansionvalve恒溫膨脹閥Evaporator蒸發(fā)器Refrigerant制冷劑TheoreticalcycleofrefrigerationRefrigeratingPlantSteeringgearelectric-hydraulicsteeringgear電動(dòng)液壓舵機(jī)Two(four)-ramhydraulicsteeringgearstock舵柄Tiller舵柱huntinggear追隨機(jī)構(gòu)Ram撞桿RPTsteeringwheeltransmitterreceiverhuntinggearfloatingleverfeedbacklinkwithpivotcylinderramrudderstockvalveblocktillercross-headcylinderisolatingvalvepumpmotorbufferspringOilseparatorPurifierclarifierseparatorbowlbowldiscgravitydisc比重環(huán)Nomogram諾模圖Anti-pollutionequipment防污染設(shè)備Sewagetreatmentplant污水處理裝置Incinerator焚燒爐Oilywaterseparator油水分離器coarseseparatingcompartmentoilcollectionspacefineseparatingcompartmentcatchplate擋板DeckmachineryCargohandlinggear,cargowinch,deckcraneWindlass起錨機(jī)capstan,mooringwinchhatchcover艙口蓋gangwayliftinggear舷梯升降裝置(7).Valves&PumpsSafetyvalvepilotvalve導(dǎo)向閥non-return(check,one-way)valve單向閥stop(shut-off,cutoff)valve截止閥by-passvalve旁通閥change-overvalve轉(zhuǎn)換閥over-flowvalve溢出閥make-upvalve補(bǔ)償閥PumpsCentrifugalpumpPositivedisplacementpumpreciprocatingpump往復(fù)泵rotarypump回轉(zhuǎn)泵ejectorpump噴射泵ballastpump壓載水泵bilgepump污水泵sanitarypump衛(wèi)生水泵sewagepump排污泵transferpump,primingpump,boosterpump(8).Tools&MetersImpactwrenchpipewrenchengineerhammeradjustablespannerscrewdriverbridgegaugeFeeler塞尺electrodeweldingmachine手工電弧焊MetersMicrometer千分尺Thermometer溫度計(jì)pressuregauge壓力計(jì)Salinometer鹽度計(jì)Viscosimeter粘度計(jì)flowmeter流量計(jì)oilmistdetector油霧檢測(cè)器indicatorpowermeter,ammeter,voltmeter,ohmmeter(9).MarineOilsmarinedieseloilmarinefueloilintermediatefueloilcylinderoil(highalkalinity)engine(crankcase,system)oilhydraulicoilanti-rustemulsionoil防銹乳化油Grease油脂Lesson1

BriefIntroductiontoMarineDieselEngines

Keywords/termsTheTwo-strokeCrossheadEngineTheMediumSpeed4-StrokeTrunkPistonEnginemainpropulsivepowerunitmerchantvesselsresidualfuelswasteheatrecoveryKeywords/termsalternatordieselelectricpropulsionnolongeralignreductiongearingTrunkPistonKeySentencesAsthepriceofoilrose,developmentsinthedesignoftheseenginesallowedthemtoburnthepoorerresidualfuels.Mediumspeedengineshaveahigherpowertoweightratiothantheslowspeedtwo-strokeengines,butduetothehigherspeedstendtohavereducedmaintenanceintervalsKeySentencesThemediumspeed4-stroketrunkpistonenginecanbefoundonmostmediumtolargemerchantvesselsevenifthemainengineiseitherasteamturbineora2-strokecrossheadengine.AdditionalSentencesMarinepowerplantisaplantthatpropelsawaterbornevessel.Therearefourmaintypesofmarinepowerplants:thedieselengine,thesteamturbine,thegasturbineandthemarinenuclearplant.Gasturbinesdifferfromsteamturbinesinthattheformerusesgastoturnashaft.ThedieselengineissimilartothegasolineengineinthatthepowerisdevelopedbythepistoninthecylinderAdditionalSentencesThereasonwhymoreandmoreofthelargemerchantvesselsarebeingpoweredbymedium-speeddieselenginesistheirsmallersizeandweight.

Mediumspeeddieselenginesareincreasinglyusedasmainengineonmerchantvessels,becausetheyhaveahigherHp/Weightratio.AdditionalSentencesTheslowspeedmainpropulsiondieseloperatesontwo-strokecycle.Atthislowspeedtheenginerequiresnoreductiongearboxbetweenitandpropeller.Typicalmarinepropulsionplantsincludeasingle,long-stroke,slow-speed,turbocharged,two-strokedieselenginedirectlycoupledtothevessel'ssinglelarge-diameter,fixed-pitchpropeller.AdditionalSentencesAmongthemainpropulsionunitsonboardtheshipwiththesamecapacity,thelightestoneisgasturbine.Dieselenginesinsteadofsteamengineswereusedasmainengineonboardshipsismainlybecausetheyhaveahigherthermalefficiency.AdditionalSentencesOwingtoitslonglife,lowercostandreliability,thelowspeedcross-headdieselengineiswidelyusedonboardshipasamainengine.Lesson2The4-strokeCycleandthe2-strokeCycleKeywords/termsThefour-strokecycleThetwo-strokecyclesuctionstroke,compressionstroke,powerstroke,andexhauststrokeclockwisefuelinjectoratomizeWorkingcycleKeywords/termsTopDeadCenterorTDCBottomDeadCenterorBDCscavengingscavengeportsKeySentencesThefour-strokecycleissocalledbecauseittakesfourstrokesofthepistontocompletetheprocessesneededtoconverttheenergyinthefuelintowork.Becausetheengineisreciprocating,thismeansthatthepistonmustmoveupanddownthecylindertwice,andthereforethecrankshaftmustrevolvetwice.KeySentencesThefourstrokesofthepistonareknownasthesuctionstroke,thecompressionstroke,thepowerstroke,andtheexhauststroke.Itisduringthisstrokethatworkenergyisbeingputintotheengine;duringtheother3strokesofthepiston,theengineishavingtodothework.KeySentencesThetwo-strokecycleissocalledbecauseittakestwostrokesofthepistontocompletetheprocessesneededtoconverttheenergyinthefuelintowork.Becausetheengineisreciprocating,thismeansthatthepistonmustmoveupanddownthecylinder,andthereforethecrankshaftmustrevolveonce.KeySentencesItisduringthisstrokethatworkenergyisbeingputintotheengine;duringtheupwardstrokeofthepiston,theengineishavingtodothework.KeySentencesAtabout140oafterTDCthepistonuncoversasetofportsknownasscavengeports.Pressurizedairentersthecylinderviatheseportsandpushestheremainingexhaustgasfromthecylinderinaprocessknownas"scavenging".ThepistonnowgoespastBottomDeadCenterandstartsmovingupthecylinder,closingoffthescavengeports.Theexhaustvalvethenclosesandcompressionbegins.AdditionalSentences(Pistonarea)×(Pistonstroke)×(numbersofthecylinders)=enginedisplacement.

Themainfactordeterminingtheoutputofeachcylinderisthecylinderbore.

ThefigurethatthevolumeofairatBDCisdividedbythevolumeofairatTDCistermedascompressionratio.AdditionalSentencesWithcylindersofequaldiameterofboreandequalrevolutions,thetwo-cycleenginedeliversapowerabout80percentgreaterthanthatofthefour-strokeone.

Inthetwo-strokeengine,inefficientscavengingandotherlossesreducethepoweradvantagetoabout1.8.

Lesson3DieselEngineConstruction（１）

Keywords/termsbedplate

rigid

bearinghousing

transversegirderalignment

flexible

hog/sagKeywords/termsholdingdownboltlongitudinalgirdercrankshaftthrow

thrustcollar

A-Frames

Keywords/terms

crossheadguideentablaturecrankcasefittedbolt

tierods(bolts)Keywords/termstightenedhydraulically

bendingmoment

jackboltcrankshaft

Keywords/termsfullybuilttypeshrink–shrunk-shrunkSemi-builttypeconnectingrod

Keywords/termsreciprocatingmotionrotarymotion

whitemetalshimtinaluminumalloyKeySentencesThebedplateisthefoundationonwhichthe2-strokeengineisbuilt.Itmustberigidenoughtosupporttheweightoftherestoftheengine,andmaintainthecrankshaft,whichsitsinthebearinghousingsinthetransversegirders,inalignment.Atthesametimeitmustbeflexibleenoughtohogandsagwiththefoundationplatetowhichitisattachedandwhichformspartoftheship’sstructure.KeySentencesIfthebedplatewastoorigid,thenasthehullflexed,theholdingdownbolts,whichsecuretheengineintotheshipwouldbelikelytobreak,andtherewouldbeadangerofthebedplatecracking.Thetrendnowadaysistobuildtheframeboxasaseparatefabricatedconstructionandthen,afterstressrelievingandmachiningthematingsurfaces,tomountitonthebedplate.Thishastheadvantageofsavingweight.KeySentencesToholdthebed-plate,framesandentablaturefirmlytogetherincompression,andtotransmitthefiringforcesbacktothebedplate,longtieboltsarefittedthroughthesethreecomponentsandthentightenedhydraulically.KeySentencesTopreventexcessivebendingmomentsinthetransversegirders,thetieboltsarepositionedasclosetothecenterofthecrankshaftaspossible.Becausethetieboltsaresoclosetothecrankshaft,someenginesemployjackboltstoholdthecrankshaftmainbearingcapinpositioninsteadofconventionalstudsandnuts.KeySentences

Onolderenginestheso-calledfullybuiltmethodwasused.Thisconsistedofforgingseparatewebs,crankpinsandmainjournals.Thecrankpinsandjournalsweremachinedandmatchingholesboredinthewebs,whichwereslightlysmallerindiameter.Thewebswereheatedupandthecrankpinsandjournalsfittedintotheholes(whichduetotheheathadexpandedinsize).Asthewebscooleddown,sothediameteroftheboredholeswouldtryandshrinkbacktotheiroriginalsize.Indoingso,thecrankpinsandjournalswouldbegrippedtightlyenoughtostopthembeingabletoslipwhentheenginewasbeingoperatednormally.KeySentencesToday,crankshaftsforlarge2-strokecrossheadenginesareofthesemibuilttype.Inthismethodofconstructionthecrankshaft"throws"consistingoftwowebsandthecrankpinaremadefromasingleforgingofa0.4%carbonsteel.Thewebsareboredtotaketheseparatelyforgedandmachinedmainjournalswhicharefittedintothewebsusingtheshrinkfittingmethoddescribedabove.KeySentencesTheadvantagesofthismethodofconstructionisthatbymakingthetwowebsandcrankpinfromasingleforgingthegrainflowinthesteelfollowsthewebroundintothecrankpinandbackdowntheotherweb.AdditionalSentences

Thebedplateissecuredbymeansofside-chockboltsandend-chockbolts.

AtthetopoftheA-framesthereisastrongcastironframecalledthescavengingairbox.A-framesandcylinderblockisheldtogetherbytierodstoformarigidstructure.AdditionalSentences

Althoughthecrankshaftsofmediumdieselenginesappeartoberobust,theyrelyonthesupportofthemainbearingstodeveloptheirfullstrength.

Amainbearingconsistsoftwoshellswhicharesecuredbymeansofstudsandbearingcaps.AdditionalSentencesThechaintransmission,formingtheconnectionbetweenthecrankshaftandthecamshaft,isenclosedinacastironcasingknownasthechaindrivecasing.Eachcrankismadeupoftwocrankwebsjoinedbyacommoncrankpintowhichthebottomendbearingisfitted.Lesson4DieselEngineConstruction（２）Keywords/termscrosshead

crossheadpinslippercrossheadguidecrossheadbearingKeywords/termsaccelerate/deceleratehydrodynamiclubricationtin-aluminumalloy

polishmirrorfinishtelescopicpipemisalignment

stuffingboxKeywords/terms

pistoncrownskirtpistonringgroovechrome-plateduniflowscavengedenginetrunkpistonengineKeywords/terms

cylinderlinerKeySentencesBecausethetopoftheconnectingrodswingsaboutthepinandchangesdirectioneachtimethepistonreachesmidstroke,therelativespeedbetweenbearingandpinatmidstrokeiszero,acceleratestoamaximumasthepistonapproachestoporbottomdeadcenterandthendeceleratesbacktozeroagainasthepistonapproachesmidstrokeandtheconnectingrodchangesdirection.KeySentencesTheloadonthepinisalwaysdownwards,soitisthebottomhalfofthebearingwhichissubjecttowear.Becauseofthehighloadsthebearingmaterialisatin-aluminumalloybondedtoasteelshell.Thepinishighlypolishedtoamirrorfinish.KeySentencesOilissuppliedtothecrossheadusingaswingingarmoratelescopicpipeandissometimesboostedinpressuretoaidefficientlubrication.Thecrownissubjectedtothehightemperaturesinthecombustionspaceandthesurfaceisliabletobeeroded/burntaway.Forthisreasonthematerialfromwhichthecrownismademustbeabletomaintainitsstrengthandresistcorrosionathightemperatures.Steel,alloyedwithchromiumandmolybdenumisused,andsomepistonshaveaspecialalloyweldedontothehottestpartofthecrowntotryandreducetheerosioncausedbytheburningfuel.KeySentences

Pistonsarecooledeitherusingwaterorthecrankcaseoil.Waterhasabettercoolingeffectthanoil,butthereisariskofleakageofwaterintothecrankcase.Modernengineshaveoil-cooledpistons.KeySentencesThelinercanbemanufacturedusingasuperiormaterialtothecylinderblock.Whilethecylinderblockismadefromagraycastiron,thelinerismanufacturedfromacastironalloyedwithchromium,vanadiumandmolybdenum.(castironcontainsgraphite,alubricant.Thealloyingelementshelpresistcorrosionandimprovethewearresistanceathightemperatures.)KeySentencesAtworkingtemperature,thelinerisalothotterthanthejacket.Thelinerwillexpandmoreandisfreetoexpanddiametricallyandlengthwise.Iftheywerecastasonepiece,thenunacceptablethermalstresseswouldbesetup,causingfractureofthematerial.KeySentences

Thecoolingwaterspacewassealedfromthescavengespaceusing“O”ringsandatelltalepassagebetweenthe“O”ringsledtotheoutsideofthecylinderblocktoshowaleakage.KeySentencesToincreasethepoweroftheengineforagivennumberofcylinders,eithertheefficiencyoftheenginemustbeincreasedormorefuelmustbeburntpercycle.Toburnmorefuel,thevolumeofthecombustionspacemustbeincreased,andthemassofairforcombustionmustbeincreased.Becauseoftheresultinghigherpressuresinthecylinderfromthecombustionofthisgreatermassoffuel,andthelargerdiameters,thelinermustbemadethickeratthetoptoaccommodatethehigherstresses,andpreventcrackingofthematerial.AdditionalSentencesInordertoincreasethewearingresistance,thecylinderlinersurfacesaresometimeschromium-plated.Insomedesignsthecylinderoilistimedsothattheoilinjectsonlyonthepistonringbelt.Aluminumpistonshavelowinertiaandhighcoefficientofthermalexpansion.AdditionalSentencesAnumberofcylinderlinersareenclosedinonecastironcasingtoformacylinderblock.Alltheringsareslightlyroundedontheirexternaltopandbottomedgestokeeptheoilfilmonthecylinderlinerduringtherunning-inperiodfornewpistonrings.AdditionalSentencesAmongtheringsofapistonthetoponeissubjectedtothegreatestloadandtemperature.Pistonsofmarinemediumspeeddieselenginesmaybemadeofaluminumalloyinordertokeeptheweightdownforbalancingpurposeathighspeed.AdditionalSentences

Eachcylinderlineronthemarinemediumspeedenginescanbereplacedwhenwornout.Foroneortwotypesofengine,thepistonandrodcanbewithdrawndownwardsfromthecylinderintothecrankcaseandthenoutthroughthecrankcasedoor.AdditionalSentences

Thepistonringsaremanufacturedwithadiameterlargerthantheboreofthecylinder.Thepistonringgroovesforastandardengineareflamehardenedagainstwear.Thecoolingwaterisindirectcontactwiththeoutersurfaceofthelinerasaresultofwhichitistermeda"wetliner".AdditionalSentencesThecoolingwaterjacketiscommontoallthecylindersbutthereareoftendividingwallstoensurethateachcylinderreceivestherightamountandflowofwater.Inthepartofthecylinderlinerinsidethescavengingairboxthereisaseriesofopeningsknownasscavengingairports.AdditionalSentencesTheexternalcircumferenceofapairofmainbearingshellsisslightlylargerthanthatoftheboreofthehousingwhichreceivesthem.Thedifferenceistermed"nip".AdditionalSentencesDieselenginemainandconnectingrodprecisionbearingsaremadeinhalves.Eachhalfexceedsone-halfthebearingcircumferencebyasmallamount.Thesmallamountistermed“crush”.FuelOilSystemKeywords/terms

fuelsupplysystemfuelinjectionsystem

maneuveringconditiondoublebottom

settlingtank

centrifugeKeywords/termsservicetankviscosityregulator

finefilter

pressureregulatingvalvefuelmain

buffer/balancetankKeywords/termssafetydevicelowtanklevelalarmsremoteoperationoftankoutletvalves

transferpumpthree-wayvalve

attherightmomentinasuitableconditionKeywords/termstimingthedelivery

atomizationofthefuel

jerkpump

commonrailKeySentencesThefueloilsystemforadieselenginecanbeconsideredintwopartsthefuelsupplyandthefuelinjectionsystems.Fuelsupplydealswiththeprovisionoffueloilsuitableforusebytheinjectionsystem.KeySentencesAslowspeedtwo-strokedieselisusuallyarrangedtooperatecontinuouslyonheavyfuelandhaveavailableadieseloilsupplyformaneuveringconditions.KeySentencesInthesystemshowninFig.13,theoilisstoredintanksinthedoublebottomfromwhichitispumpedtosettlingtankandheated.Afterpassingthroughthecentrifugesthecleanedheatedoilispumpedtoaservicetank.Fromheretheoilispumpedthroughaheaterandaviscosityregulator.Theviscosityregulatorcontrolsthefueloiltemperatureinordertoprovideoilatthecorrectviscosityforcombustion.Thefueloilisthenpassedthroughafinefilterbeforebeingsuppliedtotheinjectionsystem.Apressureregulatingvalveensuresaconstantpressureatthefuelmain.Thisvalvecanbeopenedtowarmthroughthesystembycirculatingwithheatedoil.Thebufferorbalancetankcollectsthere-circulatedoil.KeySentencesThedieseloilsupplysystemsimilarlyusesatransferpumptodrawoilfromthedoublebottomtanks.Theoilisthenpurifiedandstoredinasettlingtank.Thedieseloilentersthesystemthroughathree-wayvalvewhichpermitsthesupplyofonlyonetypeofoiltothesystem.Dieseloilrequireslessheatingandthusthechangefromonefueltoanothershouldtakeplacegraduallytoallowtemperaturesinthesystemtostabilize.KeySentencesThefunctionofthefuelinjectionsystemistoprovidetherightamountoffuelattherightmomentandinasuitableconditionforthecombustionprocess.Theremustthereforebesomeformofmeasuredfuelsupply,ameansoftimingthedeliveryandtheatomizationofthefuel.Theinjectionofthefuelisachievedbythelocationofcamsonacamshaft.Thiscamshaftrotatesatenginespeedforatwo-strokeengineandathalfenginespeedforafour-stroke.KeySentencesTheneedlevalveintheinjectorwillliftatapresetpressurewhichensuresthatthefuelwillatomizeonceitentersthecylinder.AdditionalSentencesWhenconsideringthelowestfuelsystemoperatingtemperature,cloudpointandpourpointvaluesareimportant.Thespecificgravityoffueloilisarelativevalue.Thehigherthecetanenumber,thebettertheignitionqualityofthefuel.AdditionalSentencesObviously,foragivenfueloil,itspourpointislowerthanitscloudpoint.Beforebeingusedthefuelservicetankshouldbedrainedofwaterandresiduals.Fueloilisthoughttobeoneofthemainfactorshavemuchtodowiththeoperationandmaintenanceofanengine.AdditionalSentences

Enginefuelpumpindexisthereadingattherack.Afuelinjectionpumpisnotproperlysetthuscausingeitheradvancedorretardedfiring.

Fueloiltransfersystemsusedonboarddieselpropelledvesselsarerequiredtohavetwofueloiltransferpumpsprovidedwhereoneistobeindependentofthemainengine.AdditionalSentences

Theterm'propermetering',asappliedtoadieselfuelinjectionsystem,canbebestdefinedasdeliveringthesamequantityoffueltoeachcylinderforeachpowerstrokeaccordingtoengineload.

LubricationSystem

Keywords/termsfrictionandwearsumpdraintankdrilledpassageinduplicate

mechanicallubricatorsadditiveKeySentencesThelubricationsystemofanengineprovidesasupplyoflubricatingoiltothevariousmovingpartsinanengine.Itsfunctionistoenabletheformationofafilmofoilbetweenthemovingparts,whichreducesfrictionandwear.Thelubricatingoilisalsousedasacleanerandinsomeenginesasacoolant.KeySentencesLubricatingoilforanengineisstoredinthebottomofthecrankcase,knownasthesump,orinadraintanklocatedbeneaththeengine.Theoilisdrawnfromthistankthroughastrainer,oneofapairofpumps,intooneofapairoffinefilters.Itisthenpassedthroughacoolerbeforeenteringtheengineandbeingdistributedtothevariousbranchpipes.KeySentences

Pumpsandfinefiltersarearrangedinduplicatewithoneasstandby.Thefinefilterswillbearrangedsothatonecanbecleanedwhiletheotherisoperating.Afteruseintheenginethelubricatingoildrainsbacktothesumpordraintankforre-use.KeySentencesTheoilcooleriscirculatedbyseawater,whichisatalowerpressurethantheoil.Asaresultanyleakinthecoolerwillmeanalossofoilandnotcontaminationoftheoilbyseawater.KeySentencesLargeslowspeeddiesel-enginesareprovidedwithaseparatelubricationsystemforthecylinderliners.Oilisinjectedbetweenthelinerandthepistonbymechanicallubricatorswhichsupplytheirindividualcylinder.Aspecialtypeofoilisusedwhichisnotrecovered.Aswellaslubricating,itassistsinformingagassealandcontainsadditiveswhichcleanthecylinderliner.AdditionalSentencesTheTBNvalueofdieselenginelubeoilreferstoitsabilitytoneutralizeacids.Thedemulsibilityofanoilreferstoitsabilitytomixwithwaterandthe