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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 components
B
increase fuel delivery rate and economy
C
prevent pre-ignition
D
avoid carbonization of the nozzle tips
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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When the ship is going to enter into the harbor,（）A
change from heavy fuel oil to diesel oil for mail engineB
pumping oil bilge waterC
change sea chest form high level one to lower oneD
test emergency generator
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fuel/water separatorsB
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单选题When centrifuging heavy fuel oil, an important factor to consider is the （） (1) flow rate (2) viscosity of the fuel oilA
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单选题A viscosity regulator used for an engine is usually provided in order to （） for an engine burning heavy fuel oil.A
regulate the fuel supplyB
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单选题A ship which is required to carry an Oil Record Book must log in the book（）.A
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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
the fuel oilB
the lubricating oilC
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单选题When preparing a ship for heavy weather，fuel oil day tanks should be（）.A
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单选题The safe rate of bunkering heavy fuel oil is directly related to the （）.A
type of fuel transfer pump aboardB
temperature of the fuel oil being receivedC
size of the fuel storage tanks ashoreD
distance from the fuel oil storage tanks ashore
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单选题Machinery driving fuel oil transfer and fuel oil service pumps must be fitted with a remote means of stopping the machinery from （）.A
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the throttle stationD
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单选题Proper filtering and straining of diesel fuel is important because the（）A
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单选题Differential needle valves used in fuel injectors are directly closed by（）A
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单选题The soot blowers are operating in the oil fuel boiler the air/fuel ratio must （） throughout the action, and blowers greased after use.A
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quickC
arrangedD
high
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单选题Injectors on modern engines are cooled by a combination of the intensive bore cooling in the cylinder by a combination of the intensive bore pockets and by the fuel which is re-circulated through the injector when the follower is on the （）of the cam or when the engine is stopped.A
slopeB
baseC
topD
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单选题Heavy soot accumulations in an auxiliary boiler could be caused by（）A
water in the fuel oilB
excessive cyclingC
high fuel oil pressureD
improper burner maintenance
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单选题Fuel injectors used in heavy fuel oil systems are usually provided with cooling to reduce（）.A
cold corrosion of the nozzlesB
fuel viscosity for better atomizationC
carbon accumulation on the nozzlesD
fuel detonation in the cylinders
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单选题The temperature of the fuel oil received during bunkering operations is critical in determining the（）A
expansion space to leave in a tankB
flash point at which the fuel will burnC
temperature to which the fuel must be heatedD
rate at which the fuel can be pumped during transfer operations
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单选题Proper filtering and straining of fuel oil is important because the （）.A
fuel oil pump will over-speed if dirt is not removedB
fuel oil transfer pumps cannot tolerate small amounts of dirt in the oilC
fuel injectors may be damaged by foreign particles in the fuel oilD
dirty fuel will clog the intake air filter
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单选题When running a large, low-speed, main propulsion diesel engine on heavy fuel, which of the following precautions should be observed when switching back over to diesel oil?（）A
The diesel oil must never be allowed to mix with the heavy fuelB
The temperature of the fuel from the pre–heater should be gradually reduced after switching over the three–way valveC
The heating steam to the pre-heater should be secured as soon as the diesel fuel passes through the three-way valveD
The heating steam must be secured before the diesel oil passes through the three-way valve
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