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单选题
Sea water is not used directly as a coolant because of （）.
A
low specific heat
B
high specific heat
C
corrosive action
D
high viscosity
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In a diesel engine closed freshwater cooling system, the amount of coolant flowing through the heat exchanger is controlled by the __.A.suction pressure regulatorB.thermostatic bypass valveC.sea water temperatureD.water level in the expansion tank
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共用题干
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水泥涂料用于淡水舱和双层底舱。（）A、Primer is used for sea water tanks and double bottom tanks.B、Cement wash is used for fresh water tanks and double bottom tanks.C、Varnish is used for fresh water tanks and double bottom tanks.D、Bitumen is used for fresh water tanks and double bottom tanks.
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单选题Which of the following factors tends to increase scale formation on the saltwater side of a heat exchanger used in a diesel engine cooling water system?（）A
Baffle plates that have been bent during prior removalB
Leaks in the cooler tube nestC
Operating the engine while maintaining a high sea water outlet temperatureD
A punctured sea water strainer supplying cooling water to the heat exchanger
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单选题Because of the reduced （） in the distillation system, some of the sea water boils as it flows through the tubes of the evaporator.A
pressureB
temperatureC
densityD
volume
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单选题The fresh water generator produces fresh water （）.A
by cooling sea waterB
by heating sea waterC
by evaporation of sea waterD
by purifying sea water
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单选题（）is used to prevent the entry of sea water to the machinery space.A
A special sealing glandB
PropellerC
TailshaftD
Sterntube bearing
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单选题What should you apply to a fathometer reading to determine the depth of water?（）A
Subtract the draft of the vesselB
Add the draft of the vesselC
Subtract the sea water correctionD
Add the sea water correction
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单选题In a central cooling system, used in some modem ships, sea water is supplied to cool （）which will circulate to other individual cooler, greatly reducing the corrosion problems.A
fresh waterB
sea waterC
cooling oilD
emulsion
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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
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单选题A large, low-speed, main propulsion diesel engine uses sea water to directly cool the （）.A
cylinder headsB
exhaust valvesC
scavenging airD
injectors
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单选题Which of the following statements is correct concerning diesel engine cooling water systems?（）A
Each engine must have its own engine driven cooling water pump capable of providing cooling for all ranges of operationB
propulsion engines with bores exceeding 200 mm are to be fitted with a means to display the cooling water temperature of each cylinderC
At least two independent sea suctions are to be provided for supplying water to the engine jackets or to the heat exchangersD
Suitable strain are to be fitted between the circulating pumps and heat exchangers when sea water is used for direct cooling
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单选题In a diesel engine jacket water cooler, with seawater cooling the fresh water, the（）A
sea water temperature must never be warmer than 40℃B
jacket water pressure should always be greater than the sea water pressureC
jacket water temperature must always be less than 60℃D
jacket water pressure must always be less than the sea water pressure
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单选题Because of the reduced （） in the vacuum boiling evaporator, some of the sea water boils as it flows through the tubes.A
temperatureB
water levelC
pressureD
rate of flow
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单选题The pump used to send the bilge water into the oily water separator（）the mixture because this might create finer oil particles.A
should agitateB
should not agitateC
should mix upD
should not add up
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单选题According to the SOLAS convention, the bilge water system （）A
must connect the bilge well suction directlyB
should not pump out the water accumulated in the cargosC
should not used for emergency drainage in case of ship collisionD
should connect to the fire fighting system directly
考题
单选题When water is used to fight a fire on board a ship，the effect of the weight of the water must be taken into account. How much sea water will increase the weight displacement by one ton?（）A
64 cubic feetB
35 cubic feetC
100 gallonsD
500 liters
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单选题In a central cooling system, used in some modem ships, sea water is supplied to cool （）which will circulate to other individual cooler, greatly reducing the corrosion problems.A
main bearingsB
sea waterC
cooling oilD
lower temperature fresh water
考题
单选题Sea water is not directly used as a coolant for engines because of its （）.A
low specific heatB
corrosive actionC
high expenseD
acid property
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