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单选题
Purging air from a hydraulic system is necessary when（）
A
adding small amounts of oil to the system
B
the system has been overheated
C
the system has been drained and then filled with new oil
D
the system has been idle for a long period of time
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Frequent ______ is important: fixing or changing faulty parts of the propulsion system when necessary.
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One function provided by a hydraulic accumulator is to ___.A.provide an area where air can separate from the oilB.provide an area to separate solid contaminants from the oilC.act as an oil and water separatorD.absorb shocks occurring in the system
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In an air conditioning system, moisture is removed from the air by ______.A.filtersB.separatorsC.ducted trapsD.dehumidifiers
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单选题Care and cleanliness are required when installing diesel fuel filters （）.A
to prevent the fuel system from becoming air-houndB
to prevent the fuel system becoming clogged with dirty particlesC
both of the aboveD
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单选题Air trapped in the hydraulic fluid of a steering system would be indicated by（）A
an improper rudder responseB
hammering noises in the equipment or transmission linesC
popping or sputtering noisesD
all the above
考题
单选题Air trapped in the hydraulic fluid of a steering system should be indicated by （）.A
the pump over-speedingB
an improper rudder responseC
bubbles in the sight glassD
ram relief valves lifting
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单选题The purging of air from an elector-hydraulic steering gear unit is necessary when（）A
changing over to hand pump operationB
engaging the trick wheelC
the system has been filled with new oilD
the rudder angle indicator does not match the helm position
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单选题Air blowing from the intake air filter of an operating air compressor indicates （）.A
broken inlet valvesB
broken discharge valvesC
pulsations in the air distribution systemD
overloading of the air distribution system
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单选题The fresh air intake of the inert gas system（）.A
prevents the flue gas from falling below 3% content of oxygenB
allows the inert gas piping to be used for gas freeing the tanksC
opens when there is excessive vacuum on the deck water sealD
enables outside air to mix with and cool hot flue gasses
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单选题Most hydraulic steering gears are fitted with relief valves which（）A
function when the rudder is amidshipsB
relieve excess whip pressure from the hydraulic oil systemC
protect the piping assembly from external rudder shockD
relieve excessive telemotor pressure
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单选题What is the best way of stopping an over-speeding diesel engine?（）A
Disconnect the battery cables from the starting motorB
Drain the hydraulic fluid from the governor sumpC
Block the flow of cooling air to the radiatorD
Secure the fuel supply and block the air intake
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单选题In a hydraulic system, （） are used to protect the system from over pressure.A
stop valvesB
check valvesC
safety valvesD
reducing valves
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单选题When it is necessary to open a refrigeration system for repairs and the system will be open for more than a few minutes, the open ends of the system should be （）.A
dehydratedB
purgedC
pluggedD
evacuated
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单选题In an air conditioning system, moisture is removed from the air by（）A
filersB
separatorsC
ducted trapsD
dehumidifiers
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单选题The function of the hydraulic telemotor transmitter used in an electro-hydraulic steering gear system is to （）.A
transmit the rudder angle to the bridge indicatorB
prevent the control linkage from striking the stops when hard overC
automatically purge all entrained air from the systemD
send hydraulic signals to the receiving unit
考题
单选题One function provided by a hydraulic accumulator is to（）A
provide an area where air can separate from the oilB
provide an area to separate solid contaminants from the oilC
act as an oil and water separatorD
absorb shocks occurring in the system
考题
单选题Before doing any work on a hydraulic system equipped with accumulators, you should（）A
drain the accumulators and purge with oxygenB
bleed off all stored energy from the accumulators completelyC
charge the accumulators to prevent system energy lossD
pump the hydraulic fluid into the accumulators to prevent fluid loss
考题
单选题In which of the listed hydraulic systems will the installation of an oil cooler be necessary?（）A
Constant tension mooring winch systemB
Hatch cover systemC
Watertight door systemD
Internal combustion engine hydraulic starter system
考题
单选题If a severe leak develops in the electro-hydraulic steering gear unit is necessary when（）A
Loss of vessel steeringB
Overheating of the gyrocompassC
Jamming of the six-way valeD
Jamming of the follow-up device
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单选题The primary task of the compressed air system is to deliver the starting air necessary for （）A
starting the MEB
starting the emergency electric alternatorC
driving the main turbineD
driving the turbocharger
考题
单选题In an electro-hydraulic steering gear system, when will the variable displacement pump be placed on stroke?（）A
When the helm is at any angle other than amidshipsB
When the six-way valve is openedC
When the ram relief valves liftD
When the redder angle is different from the position of the helm
考题
单选题When air becomes trapped in the hydraulic fluid of a steering system, the （）.A
rudder will respond sluggishlyB
hydraulic rams will over-speedC
sight glass will show bubblesD
ram relief valves will lift
考题
单选题Which of the following methods is normally used to control the temperature of air distributed from individual cooling coils in an air conditioning system using a chilled water circulation system?（）A
A room thermostat activates an electric heater at each individual chilled air outlet when necessaryB
Varying the number of passes the air makes across the coilsC
Varying the temperature of the water through the coilsD
Varying the quantity of water flowing through the coils
考题
单选题While troubleshooting a refrigeration system for low head pressure, liquid refrigerant flooding back from the evaporator is determined to be the causeIt may be necessary to （）.A
change the expansion valve adjustmentB
readjust the water regulating valve to increase the flow of waterC
purge air from the condenserD
clean the waterside of the condenser
考题
单选题Which of the following statements describes the functions of a reservoir used in a hydraulic system?（）A
Dissipate heatB
Trap foreign matterC
Separate air from the oilD
All of the above
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