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单选题
Although lube oils used in the main lubricating service systems should have a relatively high flash point to avoid ignition, they can create smoke and fire hazards when they（）
A
are exposed to a vacuum
B
come in contact with extremely hot surfaces
C
are reduced in temperature to just above the pour point
D
become extremely agitated or aerated
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更多 “单选题Although lube oils used in the main lubricating service systems should have a relatively high flash point to avoid ignition, they can create smoke and fire hazards when they（）A are exposed to a vacuumB come in contact with extremely hot surfacesC are reduced in temperature to just above the pour pointD become extremely agitated or aerated” 相关考题
考题
The ability of lubricating oils to resist viscosity changes during temperature changes is indicated by the ____.A.American PetroleumB.Institute number viscosity index numberC.Seconds Saybolt Furol numberD.Seconds Saybolt Universal number
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Lubrication for the main reduction gears used with diesel engines is usually supplied byA.oil from the main engine sumpB.an independent lube oil systemC.the stern bearing head tankD.the stem bearing sump tank
考题
If a used lube oil analysis indicates excessive chromate content, this meansA.air filtration is inadequateB.engine coolant is leaking into the lube oilC.fuel oil is leaking into the lube oilD.the piston rings are excessive worn
考题
In an auxiliary diesel engine bypass type lubricating oil system, the main lube oil pump forces_______ .A.all of the oil used by the engine through a filterB.some of the oil used by the engine through a filterC.some of the oil used by the engine through a centrifugeD.all of the oil used by the engine through a centrifuge
考题
The pour point of lubricating oils is affected the most by which of the following?A.Extensive centrifugingB.Wax contentC.Water contentD.Acid content
考题
单选题Heavy residual fuel oils are heated prior to centrifuging to （）A
reduce fuel weightB
increase specific gravityC
separate fuel from lube oilD
reduce fuel viscosity
考题
单选题Worn main bearings in a diesel engine can result in （）A
decreased compression pressureB
increased lube oil pressureC
lower lube oil temperatureD
excessive leakage past the piston rings
考题
单选题Lubricating systems for diesel engines are usually designed to initially provide lube oil to the engine （）A
camshaft beatingsB
main bearingsC
piston crownsD
cylinder walls
考题
单选题Telescopic pipes to the piston of a large slow-speed main propulsion diesel engine are designed to prevent （）.A
excessive crankcase pressureB
excessive lube oil temperatureC
contamination of the lube oil by waterD
contamination of the cooling water by lube oil
考题
单选题A lube oil filter can be used to remove most contaminants from lube oilA contaminant which will remain in the lube oil after filtering is （）.A
acidB
fuel oilC
sedimentD
water
考题
单选题Excessive lubricating oil consumption in a running diesel engine can be caused by （）A
clogged lube oil pipingB
excessive valve-guide clearanceC
high lube oil viscosityD
low lube oil temperature
考题
单选题To receive oil residues from the purification of fuel and lubricating oils in the machinery spaces, what kind of tank(s) should be provided on board?（）A
bilge tankB
sludge tankC
overflow tankD
oil collecting tank
考题
单选题You are inspecting the lower main precision bearings on a diesel engine.You observe that about half the thin Babbitt linings are of a milky white colourThis condition is caused by （）A
large dirt particles in the oil supplyB
insufficient lubricating oil and overheatingC
normal wearD
water contamination of the lube oil
考题
单选题The ability of lubricating oils to resist viscosity changes during temperature changes is indicated by the（）A
American PetroleumB
Institute number viscosity index numberC
Seconds Saybolt Furol numberD
Seconds Saybolt Universal number
考题
单选题A lube oil sample taken from the main engine lube oil system has dark yellow opaque color.This is the result of （）A
water contaminationB
mixing oils of two widely different viscositiesC
overheatingD
aeration
考题
单选题（） is used for cylinder and cylinder head, the salt water is used for cooling the lubricating oil, the fresh water in the coolers and the charging air in the air cooler.A
The fuel oilB
The lube oilC
The sea waterD
The fresh water
考题
单选题Sludge may form in the lubricating oil crankcase of a reciprocating air conditioning compressor as a result of （）.A
wax precipitation in the lube oilB
contamination by dust, scale, or moistureC
refrigerant bubbles in the lube oilD
refrigerant reducing the lube oil viscosity
考题
单选题In a normally operating diesel engine, the main cause of lubricating oil contamination in the crankcase is a result of the （）.A
metal particles loosened by wearB
air when no air cleaners are usedC
condensation of water vaporsD
breakdown of the lubricating oil by dilution
考题
单选题Sludge formation in a diesel engine lube oil system is caused by（）A
carbonization of oils from the combustion chambersB
emulsions of lube oil and waterC
coagulation of unburned fuel below the piston ringsD
all of the above
考题
单选题If a used lube oil analysis indicates an excessive chromate content, this means （）A
air filtration is inadequateB
engine coolant leaking into the lube oilC
fuel oil is leaking into the lube oilD
the piston rings are excessively worn
考题
单选题If the analysis of used lube oil indicates a high content of iron particles, this could indicate（）A
corrosive deterioration of a bearingB
inadequate air filtrationC
excessive ring and liner wearD
excessive cooling of lubricating oil
考题
单选题If a used lube oil analysis indicates excessive fuel dilution, the lube oil should be （）A
changedB
centrifugedC
filteredD
settled
考题
单选题Lubricating oil viscosity in an operating diesel engine can be reduced by（）A
increasing cooling water flowB
increasing lube oil flowC
dilution by fuel oilD
adding SAE 70 oil
考题
单选题The pour point of lubricating oils is affected the most by which of the following?（）A
Extensive centrifugingB
Wax contentC
Water contentD
Acid content
考题
单选题（） fuel oils （） lubricating oils require treatment before passing to the engine.A
Both；andB
Neither；norC
Either；orD
Both；or
考题
单选题The （）pump is usually used as the lubricating oil pump.A
turbineB
screwC
vaneejectorD
centrifugal
考题
单选题There should be a lubricating oil （） between the main beatings and the crankshaft.A
filmB
capC
lacquerD
shell
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