NewWordsandExpressionscomplexity[k?m?pleks?ti]n.復(fù)雜，復(fù)雜性grade[ɡre?d]n.等級(jí)；級(jí)別geared[ɡ??d]a.齒輪傳動(dòng)的，變速螺旋槳的auxiliary[??ɡ?z?li?ri]a.輔助的；（發(fā)動(dòng)機(jī)、設(shè)備等）備用的miscellaneous[?m?s??le?ni?s]a.各種各樣的；多方面的trunkpiston

筒式活塞cylinderlubrication

氣缸潤滑doublebottom

雙層底NewWordsandExpressionsbellmouth

喇叭口，錐形口wetsump

濕式油底殼list[l?st]n.橫傾trim[tr?m]n.縱傾sloshing[slɑ?]n.晃動(dòng)，晃蕩precaution[pr??k???n]n.預(yù)防，預(yù)防措施turbocharger[?t??b??t?ɑ?d??(r)]n.渦輪增壓器emergency[??m??d??nsi]a.緊急的NewWordsandExpressionsspin[sp?n]v.旋轉(zhuǎn)contamination[k?n?t?m??ne??n]n.污染；污染物inevitable[?n?ev?t?bl]a.必然的，不可避免的straightmineraloil

純礦油corrosion[k??r???n]n.腐蝕oxidation[??ks??de??n]n.[化學(xué)]氧化inhibitor[?n?h?b?t?(r)]n.抑制劑，抗化劑alkalineadditive

堿性添加劑NewWordsandExpressionstotalbasenumber（TBN）

總堿值sulfurcontent

含硫量，硫分；硫含量compensate[?k?mpense?t]v.補(bǔ)償；抵消vaporize[?ve?p?ra?z]v.蒸發(fā)；使…蒸發(fā)ignite[?ɡ?na?t]v.點(diǎn)燃；使燃燒thermostatically[?θ??rm??st?t?kli]a.恒溫地；自動(dòng)調(diào)節(jié)溫度地three-waythermostaticallycontrolledvalve

溫控三通閥short-circuiting

短路效應(yīng)NewWordsandExpressionsredeem[r??di?m]v.恢復(fù)reclamation[?rekl??me??n]n.再利用analogous[??n?l?ɡ?s]a.類似的NewWordsandExpressionsdeaerate[di'?ret]v.使除去空氣；從液體中除去氣泡atmospheric[??tm?s?fer?k]a.大氣的，大氣層的boosterpump

增壓泵，升壓泵injectionpump

噴射泵，注射泵combustion[k?m?b?st??n]n.燃燒atomization[,?t??ma?'ze???n]n.霧化Thecomplexityofmotor-shiplubricatingoil(LO)systemsistheresultofthenumberofdifferentgradesofoilrequired.Ageared,mediumspeeddieselplantwillusuallyrequiredifferentgradesofoilforthemainandauxiliaryengines,andothergradesforgearingandmiscellaneoususes.ALOsystemforalowspeeddieselplantwillbeequallycomplex.Involvingatleasttwogradesofoilforthemainengine(oneforthecirculatingsystemandtheotherforthecylinders)andathirdfortheauxiliaryengines.Itisimportanttonotethatmosttrunkpistonenginesdonotuseaseparategradeofoilforcylinderlubrication.5.1Fillingandtransfersystems6.1MainengineLOcirculatingsystemAtypicalcirculatingoilsystemappearsinFig.6-1.Oildrainingfrombearingsandcoolingpassagestothebottomofthecrankcasepassesintoadraintank(orremotesump)builtintothedoublebottombelowtheengine,fromwhichitisdrawnbytheLOcirculatingpumpforredistributionviaacoolerandafilter.Althoughthedraintankisshownasanintegralpartofthedoublebottomstructure,insomecasesindependenttankshavebeeninstalled.Insmallerenginestheadditionalcostandcomplexityofadraintankareofteneliminatedinfavorofawetsumpformedbythecrankcasebottom（雖然泄放柜可以作為雙層底的組成部分，但在某些情況下，已經(jīng)安裝了獨(dú)立的油柜。在較小的柴油機(jī)中，采用濕式油底殼可以消除額外的成本和安裝泄放柜的復(fù)雜性）。6.1MainengineLOcirculatingsystemThesuctionbellmouthsclearthebottombyabout100mmtoavoidingestingwaterorsediment,andmayincorporateafootvalvetokeepthesuctionlinefullwhenthepumpisstopped.Thedraintankorwetsumpmustbesodesignedthatsuctionwillbemaintainedatthemostextremeconditionsoflist,trim,andsloshing.6.1MainengineLOcirculatingsystemTheLOcirculatingpumpsaremostoftenpositivedisplacementrotarypumps,andinlargerplantsarefittedinduplicate.Bothpumpsaremotordrivenininstallationswithlowspeeddiesels,buthigherspeedenginesareoftenfittedwithanengine-drivenpump,relyingonthemotor-drivenpumpforstandbyservice.Eachpumpwillhaveacoarsesuctionstrainerforitsownprotection.Providingeachpumpwithitsownsuctionlineisanadvisableprecaution.滑油循環(huán)泵通常是容積式旋轉(zhuǎn)泵，大型柴油機(jī)上是成對(duì)安裝的。在低速柴油機(jī)裝置中，這兩個(gè)泵都是由電動(dòng)機(jī)驅(qū)動(dòng)的，但高速柴油機(jī)通常配備發(fā)動(dòng)機(jī)驅(qū)動(dòng)的泵，依靠電動(dòng)機(jī)驅(qū)動(dòng)的泵作為備用。每個(gè)泵都有一個(gè)粗的吸入過濾器來保護(hù)自己。為每個(gè)泵提供單獨(dú)的吸油管道是明智的預(yù)防措施6.1MainengineLOcirculatingsystemAfullflowfilterisprovidedinthepumpdischargelinebeforeorafterthecooler.Itmaybeoftheduplex,baskettype,butbetterfiltrationwillbeprovidedbyadisposable-elementorself-cleaningsimplexunit,withastandbyfilterinabypass.Filteredoilisdistributedtoenginebearings,forgoverningandcontrolservice,tovalvegear,and,ontrunkpistonenginesaswellassomecrossheadengines,topistonsforcooling.Someoftheseservicesmayrequirehigherpressureoil,whichcanbeobtainedbyfittingboosterpumpsintheline.Inothercasessomeequipmentisservedbyindependentcirculatingsystemsthatarescaled,downversionsofthemainsystem(這些應(yīng)用中的一些可能需要更高的壓力油，可以通過在管路中安裝增壓泵來獲得。在其他情況下，一些設(shè)備由獨(dú)立的循環(huán)系統(tǒng)提供，這些循環(huán)系統(tǒng)是主機(jī)(滑油)系統(tǒng)的縮小版).6.1MainengineLOcirculatingsystemUsuallyoilisalsosuppliedtoturbochargerbearingsfromthecirculatingoilpumps,butsometurbochargersareprovidedwiththeirownself-containedLOsystem.IneithercasetheturbochargersmustbeprovidedwithanemergencysupplyofLO,astheywillcontinuetospinathighspeedfollowingaLOfailure.ThesystemofFig.6-1includesagravitytankforthispurpose.通常也通過循環(huán)油泵向渦輪增壓器軸承供油，但有些渦輪增壓器有自己獨(dú)立的滑油系統(tǒng)。在任何一種情況下，必須為渦輪增壓器提供一個(gè)緊急備用的滑油供應(yīng)，因?yàn)樗鼈儗⒃诠┯凸收虾罄^續(xù)高速旋轉(zhuǎn)。圖6-1的系統(tǒng)中包括為此目的設(shè)置的重力油柜。6.1MainengineLOcirculatingsystemIncrossheadengines,thecrankcase,andthereforethecirculatingoil,isprotectedbythepistonrodpackingfromcontaminationbycombustionproductsblowingbythepistonrings,whereasthiskindofcontaminationintrunkpistonenginesisusuallyinevitable.Consequently,whileastraightmineraloilwithcorrosionandoxidationinhibitorsisusuallyrecommendedforthecirculatingoilofmostcrossheadenginesregardlessofthefuelinuse,manufacturersoftrunkpistonenginesgenerallyrecommendadetergentoilwithalkalineadditives(measuredastotalbasenumberorTBN)matchedtothelikelysulfurcontentofthefueltobeburned.6.1MainengineLOcirculatingsystemWhilethecirculatingLOinacrossheadenginerarelyrequiresreplacementinthenormalcourseofevents,thisisnotusuallythecasewithtrunkpistonengines,where,inmostcases,theLOmustberenewedperiodically.ThelifeoftrunkpistonengineLOalreadyextendedbytheregularadditionoffreshmakeupoiltocompensateforoilburnedincylinderlubrication.Itcanbefurtherextendedbytakingsuchextrameasuresasthefittingofadditionalextra-finefiltrationloopsand,ifnecessary,theoccasionaladditionofchemicaladditivepackagestotheoil.筒形活塞式柴油機(jī)的滑油壽命已經(jīng)通過定期添加新鮮的補(bǔ)充油以彌補(bǔ)在氣缸潤滑中燃燒的油得到延長。如果采取額外的措施，如安裝額外的超細(xì)過濾回路，必要時(shí)還可以在油中臨時(shí)添加一些化學(xué)添加劑，則可進(jìn)一步延長其使用壽命。6.1MainengineLOcirculatingsystemThereisthepossibilityofacrankcaseoverpressureconditionorexplosioninanydieselengine.Acommonpatternbeginswhenanoverheatingbearingvaporizesoil,creatinganexplosivemixturewhichcanthenbeignitedbyfurtheroverheatingofthebearingor,intrunkpistonengines,byblowby.Togivewarningofoverheatingbearings,alarmsystemsoflargeenginesincludetemperatureprobesatmajorbearingswithinthecrankcase,whilephotoelectricoilmistdetectorscontinuouslysampletheairdrawnfromlikelyaccumulationpointswithinthecrankcase.Shouldanignitionoccur,aninitialriseincrankcasepressurewillbelimitedbyavailabilitywithinthecrankcase.6.1MainengineLOcirculatingsystemButifthisisfollowedbyaninfluxofair,amuchlargersecondaryexplosioncanoccur.Tominimizethepossibilityofthecrankcasebeingbreachedbyaprimarypressureriseandofairenteringtocauseasecondaryexplosion,largeenginesarefittedwithspring-loadedpressurereliefvalves(usuallymountedonthecrankcasedoors)whichopentorelieveanoverpressureandthensnapshut.Inaddition,thecrankcaseventpipeisrestrictedinsizetolimittheingressofair.6.1MainengineLOcirculatingsystemTheextentofadditionalautomationofthesystemwillvary,butwilltypicallyincludeautomaticchangeoverforthepumps,lowpressurealarms,alowLOpressuretrip,andadifferentialpressurealarmatthefilter.LOtemperatureisusuallycontrolledbyathree-waythermostaticallycontrolledvalveontheoilsideofthecooler.6.2MainenginecylinderoilsystemCrossheadenginesarefittedwithanindependentcylinderoilsystemforlubricationofthepistonrings.AtypicalsystemisincludedinFig.6-1.Thecylinderoilisstoredinoneor,preferably,twotanksandistransferreddailytoasmallcapacitymeasuringtank,fromwhichitpassesbygravitytothecylinderlubricatorsontheengine.十字頭式柴油機(jī)裝有獨(dú)立的氣缸油系統(tǒng)用于活塞環(huán)的潤滑。圖6-1中包含了一個(gè)典型的系統(tǒng)。氣缸油儲(chǔ)存在一個(gè)或兩個(gè)(最好是兩個(gè))油箱中，每天被轉(zhuǎn)移到一個(gè)小容量的計(jì)量油柜中，通過重力將其傳遞到發(fā)動(dòng)機(jī)的氣缸注油器中。6.2MainenginecylinderoilsystemThelubricatorsarepreciselycalibratedinjectors,mechanicallydrivenbytheengineandtimedtoinjectameteredquantityoftheoilintothecylinderasthepistonringpackrisespasttheinjectionpoints.Theoilisultimatelyconsumed.Incrossheadenginesingoodconditionthecylinderoilconsumptionmayrangefrombelow0.5g/hp-hrtobelow1.0g/hp-hr.Becausethequantitiesofoilinjectedperstrokearesmall,themeasuringtankprovidesforconsumptiontobedeterminedaccuratelyasadropinleveloveranelapsedtimeperiod.6.2MainenginecylinderoilsystemCylinderoilisahighviscositymineraloil,withaTBNmatchedtotheanticipatedsulfurcontentofthefuel.TwocylinderoilstoragetanksprovideflexibilityinthisregardbyenablingcylinderoilofdifferentTBNtobecarried.Cylinderoilstoragetanksarefilledfromdeckbygravity,afactwhichmayprecludefillingthemeasuringtankfromthestoragetanksbygravityaswell,necessitatingasmallhand-ormotor-driventransferpump.6.2MainenginecylinderoilsystemIntrunkpistonenginesingoodcondition,cylinderlubricationconsumesupto1g/hp-hrormoreofcirculatingoil,whichusuallyreachestheringpackandcylinderlinerwallsbyacontrolledleakagefromthewristpinbearing.Insomeofthelargermediumspeedengines,circulatingoilisinjectedforcylinderlubricationinthesamemannerasdescribedaboveforcylinderoilinlowspeedengines.Intheseenginestheoilisusuallytakenfromthecirculatingsystem,butseparateoiltanksandpipingcanbearrangedtobringonlyclean,unuseddetergentoilofhighTBNtotheinjectors.Thearrangementwillstillfallshortofwhatcanbeachievedinacrossheadengine,sinceanunburnedportionoftheinjectedoil,cardingentrainedcontaminants,willdraintothecrankcase.6.3LOstorage,transfer,andpurificationsystem6.3LOstorage,transfer,andpurificationsystemWhilesmallerhighspeedmainenginesmayrelysolelyonfiltrationandoccasionaloilchangestomaintainthequalityofthecirculatingoil,mostlargermainenginesarearrangedforcontinuousbypasspurificationusingcentrifugalpurifiers,asshowninFig.6-2.較小的高速主機(jī)可能僅依靠過濾和偶爾的換油來維持循環(huán)油的質(zhì)量，而多數(shù)較大的主機(jī)則采用離心式分油機(jī)進(jìn)行連續(xù)旁路凈化，如圖6-2所示。6.3LOstorage,transfer,andpurificationsystemTwopurifiersareshown,althoughoneisastandbyunit,anditisoftenpossible,bymeansofblankedcrossconnectionsorsharedcomponents,torelyonareserveFOpurifierforstandby.Normally,thepurifierdrawsfromabellmouthinthesuctionwellofthemainenginedraintankandreturnstheoiltotheforwardendofthesametank,therebyavoidingshort-circuiting.Thepurifiersuctionwillgenerallybelocatedaftofthecircuitingpumpsuction,andlowerabout50mmabovethetankbottomtodrawwaterbeforeitreachesthecirculatingpumpsuctions.6.3LOstorage,transfer,andpurificationsystemThemainLOstoragetank,withacapacityequaltoatleastonechargeforeachengineitservesplussufficientmargintomeetmiscellaneousneeds,isfilledfromdeckbygravity,whilethesettlingtankisnormallyempty.Shouldanengine’scirculatingoilbemassivelycontaminated,forexamplebywater,itcanbetransferredtothesettlerusingthetransferpump,andfreshoilbroughtdownfromthestoragetank.Iftheoilcannotthenberedeemedbyacombinationofsettlingandpurification,itcanbedischargedashoreortoabargeforreclamation.如果柴油機(jī)的循環(huán)油被大量污染，例如被水污染，它可以通過輸送泵輸送到沉淀柜，并從儲(chǔ)存柜中取出新鮮的油。如果油不能通過沉淀和凈化的組合進(jìn)行恢復(fù)性能，則可以將其排放到岸上或駁船上進(jìn)行回收。6.3LOstorage,transfer,andpurificationsystemModernpurifierstendtobeselfcleaningandfullyautomated.Generally,purifierfeedpumpsareattached,positivedisplacementunits,requiringtheLOpurifierstobelocatedonthefloorplatestominimizethesuctionliftrequiredfromthemainenginedraintank.Analternativearrangementwouldplaceamotor-drivenpurifierfeedpumponthefloorplates,toprovidemoreflexibilityinpurifierlocation.現(xiàn)代分油機(jī)往往是自我清潔和完全自動(dòng)化。一般情況下分油機(jī)給油泵是附加的，容積式單元，要求滑油分油機(jī)位于地板上，以減少從主機(jī)儲(chǔ)存柜所需的吸引壓頭。另一種替換布置是在地板上放置一個(gè)電動(dòng)分油機(jī)給油泵，以提供更靈活的分油機(jī)位置。6.3LOstorage,transfer,andpurificationsystemInmostinstallations,oilleavesthepurifiersundersufficientheadtoreachthesettlingtank,butwherethisisnotthecase,adischargepumpmustbefitted.Eachpurifierisnormallysizedtocirculatethemainenginedraintankthreetofivetimesperday.PurifierconnectionscanbeprovidedforbatchpurificationofauxiliaryengineLObutareunlikelytobeused,sincerelativelysmallquantitiesareinvolved,sincethealkaline-additivedetergentoilwillrequirerenewalatintervalsinanyevent,andsincethereispotentialforcontaminationofthemainengineoil.Whenauxiliaryenginesofsubstantialsizeareinvolved,however,aseparatepurifiermaybejustified.Thefixedpipingshownforfillinganddrainingtheauxiliaryenginesumpsmaynotbeprovidedforsmallerinstallations.6.3LOstorage,transfer,andpurificationsystemAnanalogousproblemexistsinmediumspeeddieselplants,wherethereductiongearcontainsastraightmineraloilthatissubjecttowatercontaminationfromcondensationwithinthegearcase,butwhichwouldotherwiselastindefinitely.Againbecauseofthedangerofcontamination,inthiscaseofthegearoilbythealkalinemainengineoil,evenwhenpurifierconnectionsarefittedtheyareunlikelytobeused.Someoperatorsfitwater-absorbingfiltersinthegearlubricationsystem,whileotheronoccasionalbatchpurificationusingaportablepurifierorfilter.一些操作人員在齒輪潤滑系統(tǒng)中安裝了吸水過濾器，而其他操作人員則偶爾使用便攜式分油機(jī)或過濾器進(jìn)行批量凈化。

Exercises1.What’sthefunctionofthecharacterTBNaboutcylinderoil?A.Increasingtheviscosity B.DecreasetheviscosityC.Neutralizetheacidingredient D.Evaluatetheflashpoint2.Whichofthefollowingmethodsisnormallyusedtolubricatebearingsinasmallhigh-speeddieselengine?A.Splashlubrication B.PressurelubricationC.Sightfeedlubricators D.MechanicallubricatorsCA

Exercises3.Itisimportanttonotethatmost_____donotuseaseparategradeofoilforcylinderlubrication.A.trunkpistonengines B.crossheadengines