轮机英语7.docx

轮机英语7.docx

《轮机英语7.docx》由会员分享，可在线阅读，更多相关《轮机英语7.docx（13页珍藏版）》请在冰豆网上搜索。

轮机英语7

试题七

一、单项选择题：

1.Mediumspeedengineshavea_____powertoweightratiothantheslowspeedtwostrokes,butduetothehigherspeedstendtohave_____maintenanceintervals.

A.higher/reducedB.higher/increasedC.lower/reducedD.lower/increased

2.Thepurposeoftheskirtortrunkinfour-strokecycleenginesistoactinasimilarmannertoa_____.

A.crossheadB.crownC.pistonrodD.connectingrod

3.Theconnectingrodisfittedbetweenthecrossheadandthecrankshaft.Ittransmitsthefiringforce,andtogetherwiththecrankshaftconvertsthe_____motiontoa_____motion.

A.rotary/reciprocatingB.upanddown/foreandaft

C.foreandaft/upanddownD.upanddown/rotary

4.Thepercentageofimpuritiesinaspecificfueloilsampleisdeterminedby______.

A.settlinginafueltankB.testinginalaboratorycentrifuge

C.burninginacalorimeterD.testinginaclosedcup

5.Thecylinderoilwillhavetoneutralizetheacidicproductsofcombustionandhavegood______propertiestokeepthemetalsurfacesclean.

A.detergentB.de-oilingC.defrostingD.demulsifying

6.Whichoftheprocesseslistedconsumesthegreatestamountofpowerwhileproducingthegreatestamountofheat?

A.OvercomingslidingfrictionB.Overcomingrollingfriction

C.OvercomingfluidfrictionD.Overcomingoilwedgefriction

7.Disastrousexplosionshavebeencausedbyaccumulationsofoiloroilvapourinairlinesnotdrained.Accordingtotheabovesentence,whichofthefollowingstatementsistrue?

A.Oilvapourinairpipingaredangerous.B.Explosionwillcauseoilvapouringinairlines.

C.Oilvapourinairpipingshouldbedrained.D.Oilinairpipingshouldnotbedrained.

8.Thediffuserpreventspressurepulsesfromonecylinder______anotherduringoperation.

A.tointerferewithB.interferingwithC.tohelpscavengingD.helpingscavenging

9.______istheremovalofexhaustgasesbyblowinginfreshair.

A.GasexchangeB.ChargingC.ScavengingD.Supercharging

10.Indicationsof_____arelossinpowerandirregularrunningoftheengine,highexhausttemperaturesofcorrespondingunits,highlocaltemperatureinscavengetrunk,surgingofturbocharger,andsparksandsmokeemittedfromscavengedrains.

A.acrankcaseexplosionB.ascavengefire

C.abnormalcompressionratioD.incorrectair/fuelratio

11.Somevesselsareequippedwithawaterlubricatedsterntube.Whenatsea,operatingundernormalconditions,thewaterservicevalvefromtheship'ssaltwatersystemtothebearingshouldbe______.

A.closed,andnoleakagepermittedacrosstheshaftpacking

B.closed,andonlyslightleakagepermittedacrosstheshaftpacking

C.opened,andnoleakagepermittedacrosstheshaftpacking

D.opened,andonlyslightleakagepermittedacrosstheshaftpacking

12.Thetwo-strokecyclebeginswiththepistoncomingupfromthebottomofitsstroke,withscavengeportsinthesidesofthecylinderbeing______.

A.shutB.closingC.openedD.closed

13.Theprocessofloopscavengeisthattheexhaustwillbeviaports______theairportsandcontrolledbythesamepiston.

A.behindB.farfromC.adjacenttoD.infrontof

14.Theabilityofthegovernortopreventfluctuationsinenginespeedistermed______.

A.sensitivityB.stabilityC.promptnessD.speeddroop

15.Fuelinjectionequipmentmustbekeptingoodcondition,timedcorrectly,andthe_____ineachcylindermustalsobecarefullybalancedsothatindividualcylindersarenotoverloaded.

A.MIPB.MCRC.MEPD.BHP

16.Allofthedieselenginecylinderfiringpressuresarenormal,yetalloftheexhausttemperaturesarelow.Whichofthefollowingsituationsisresponsibleforthiscondition?

A.Excessivelyearlyinjectiontiming.B.Combustionknock.

C.Leakingpistonrings.D.Lightload.

17.Loadcontrolonadieselengineisaccomplishedby______.

A.regulatingthespeedoftheturbochargerB.rotatingthefuelinjectorpumpplunger

C.regulatingthespeedofthefueloiltransferpumpD.changingenginetiming

18.Inreducingenginespeedtoanefficientpropellerspeedbytheuseofreductiongears,______.

A.speedandtorquearebothreduced

B.speedisreducedandtorqueremainsunchanged

C.speedisreducedandtorqueisincreased

D.speedissometimesunchangedwhiletorqueisincreased

19.Beforestartingareciprocating,steam-drivenpumpthathasbeenidleforaperiodoftime,youshould______.

A.openthesteamlinerootvalveB.drainthesteamcylinder

C.closethesteamcylinderdrainsD.opentheliquidcylinderdrains

20.Thebasicfunctionofthecentrifugalpumpimpelleristo______.

A.directlyincreasethepressureoftheliquidbeingpumped

B.directlyincreasethevelocityoftheliquidbeingpumped

C.convertthepotentialenergyoftheliquidtokineticenergy

D.separateairfromtheliquidbeingpumped

21.Strainers,sometimescalled______,aredevicesdesignedtopreventthepassageofunwantedsolidsintoorfurtheralongasystem.

A.dampersB.filtersC.stoppercircuitsD.separators

22.Deckmachinery,whichisalsoknownashullmachinery,includesallpowerdrivenequipmentlocated_____themachineryspacesthatis_____withthemainpropulsionplant.

A.inside/associatedB.inside/notassociatedC.outside/associatedD.outside/notassociated

23.Impropermaintenanceofanautomaticauxiliaryboileroilburnercouldresultin______.

A.fuelpumpfailureB.fanmotorfailure

C.increasedfeed-waterconsumptionD.decreasedboilerefficiency

24.Theconcentrationoftotaldissolvedsolidsinthewaterofanauxiliaryboilercanincreaseasaresultof______.

A.seawatercontaminationB.frequentsurfaceblows

C.dissolvedoxygendeaerationD.frequentbottomblows

25.Whenstarted,acompleteoilywaterseparatingunitisfirstfilled______.Theoilywatermixtureisthenpumpedthroughtheinletpipeintothecoarseseparatingcompartment.

A.withdirtywaterB.withcleanwaterC.byoilywaterD.bymixedwater

26.Whenacentrifugeisarrangedtoseparateimpuritiesandsmallamountofwaterfromoil,itisknownasa______.

A.purifierB.separatorC.filterD.clarifier

27.Thepumpusedtosendthebilgewaterintotheoilywaterseparator_____themixturebecausethismightcreatefineroilparticles.

A.shouldagitateB.shouldnotagitateC.shouldmixupD.shouldnotaddup

28.Thetrendnowadaysistobuildtheframeboxasaseparatefabricatedconstructionandthen,afterstressrelievingandmachiningthematingsurfaces,tomountitonthe_____.Thishastheadvantageofsavingweight.

A.seatingB.bed-plateC.entablatureD.cylinderblock

29.Accordingtotheinternationalregulationsconcerningthepreventionofpollutionofseaareasfromships,thedisposalintotheseaofallplasticsis______.

A.welcomeB.admittedinsomespecialseaareasC.prohibitedD.acceptable

30.Becauseofthehighloadsthebearingmaterialisatin-aluminumalloybondedtoasteelshell.Thecrossheadpinishighlypolishedtoa_____.

A.flatsurfaceB.mirrorfinish

C.slopingsurfaceD.inclinedsurface

31.Humansarestillneededtomonitortheconditionoftheboilerallthetimethelatterisoperated,_____itisjusttoacknowledgeanalarmbuzzerorflashinglightinacontrolroom.

A.evenifB.sothatC.suchthatD.inorderthat

32.Thehandsteeringisamethodbywhichthemotionoftherudderiscontrolledwith______.

A.amotor-drivensteeringwheelB.apneumaticsteeringwheel

C.ahand-drivensteeringwheelD.anelectricsteeringwheel

33.Withreferencetoanaxialpistonpump,whichoneofthefollowingstatementsistrue?

A.Thecylindricalbarreliscoupledtothemotor

B.Thecylindricalbarrelhasanoddnumberofbores

C.Theboresendinsockets

D.Thesocketsfitintheswashplate

34.Withreferencetooperatingafour-ramsteeringgearsystemunderemergencyconditions,whichoneofthefollowingstatementsisincorrect?

A.Onlyonepumpshouldbeusedatanytime

B.Theshipspeedshouldbereducedto70%ofthenormal

C.Watchkeepingofthesteeringgearshouldbeincreased

D.Limitationsofthesteeringgearshouldbeloggedbutthebridgeneednotbeinformed

35.Aknockingsoundfromonecylinderofanoperatingaircompressorindicates______.

A.adefectiveorbrokenhighpressureun-loaderB.aloosevalveplate

C.excessiveoverloadD.nocompression

36.Thevacuummaintainedinthesaltwaterfeedheatershellofaflash-typeevaporatorisgenerallyaccomplishedby______.

A.aseparateairejectorunit

B.adirectunimpededconnectionbetweensecondstageandsaltwaterfeedheater

C.eitherbyvacuumdragoranexternallinefromthefirststageviaafixedorifice

D.thefixedorificeprovidedinthesteamsupplyline

37.Whichofthelistedoperatingconditionswouldhavethegreatesteffectonthevolumetricefficiencyofanoperatingreciprocatingaircompressor?

A.Thedensityoftheairenteringthecompressor

B.Thetemperatureoftheairenteringthecompressor

C.Thedesignedrotatingspeedofthecompressor

D.Aleakingheadgasket

38.Theunloadingsystemonanaircompressorwill______.

A.increasecompressordischargepressureondemand

B.increasecompressoroperatingspeedasnecessary

C.allowthemotortoturnthecompressoropposedonlybyfriction

D.reducethecompressorfrictionalloadwhenstarting

39.Astherefrigerantpassesthroughthevalveorifice.itspressureisreducedandpartoftherefrigerantturnsinto______.

A.liquidB.oilymixtureC.emulsionD.vapor

40.Whenaddingoiltoarefrigerationsystem,