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单选题
The pistons are cooled by oil supplied from the forced （） system.
A
fresh water
B
sea water
C
lubrication
D
fuel oil
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单选题In motor-ships, （）, after passing through main and motion bearings and oil cooled pistons, etcis either retained in the bedplate.A
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单选题Trunk type diesel engine pistons are effectively cooled when heat is（）A
radiated through the engine blockB
transferred to water cooled cylinder wallsC
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transferred to escaping exhaust gases
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单选题The pistons are cooled by （） oil from the forced lubrication.A
being givenB
givingC
supplyingD
being supplied
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单选题Injectors for use with heavy fuel oil must be cooled by either water or light oil to （）A
prevent heat corrosion to internal componentsB
increase fuel delivery rate and economyC
prevent pre-ignitionD
avoid carbonization of the nozzle tips
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单选题Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）A
double bottom fuel oil tank temperatureB
heater supply steam flowC
pressure of the fuel supplied to the burnersD
attemperator steam flow in the heater discharge circuit
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单选题The lubricating system for the cylinder walls is different from the bearings in that the oil for former one is supplied in （） while that for latter one is （）.A
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measured quantity；sufficientC
excessive quantity；sufficientD
the less quantity the better；the more the better
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单选题On engines having oil cooled pistons the lubricating oil pre-heater must be put into operation and the rate of heating so （） that the temperature of the piston cooling oil returns are 32℃ to 35℃ over a period of at least two hours.A
slowB
quickC
arrangedD
high
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单选题When an oil fire has been extinguished, the surface of the oil should be kept covered with foam to prevent （）.A
air from contacting the oil vaporsB
permitting re-ignition boiling of the heated oilC
spontaneous combustion below the oil surfaceD
toxic fumes from escaping to the surface
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单选题Trunk-type diesel engine pistons are most effectively cooled by heat（）A
conducted through the engine blockB
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单选题If an emergency pump control is used as the emergency shutdown on a tanker，it must（）.A
stop the flow of oil at the main deck manifoldB
prevent the oil from leaving the shore facilityC
prevent the oil from siphoning through the pumpD
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单选题（） providing lubricating films, oil used in marine diesel engines have to remove heat from oil cooled piston.A
Except forB
BesideC
ExceptD
In addition to
考题
单选题The pistons are cooled by oil supplied from the forced （） system.A
fresh waterB
sea waterC
lubricationD
fuel oil
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单选题Oil is supplied to the crosshead using a swinging arm or a （） and is sometimes boosted in pressure to and efficient lubrication.A
telescopic pipeB
large bore pipeC
generating pipeD
central pipe
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单选题The crank chamber oil （）.A
can be recoveredB
is only supplied to cylindersC
only feeds the main bearingD
is a kind of detergent
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