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单选题
A cutoff valve in the fire-main system of a ship may be closed to protect the portion of the system on an exposed deck from（）.
A
damage from crane operations
B
being used for wash down purposes
C
accidental diversion of flow to wrong location
D
freezing
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单选题If a refrigeration system compressor crankcase is sweating, you should （）.A
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单选题General radio communications in the global system are those between（）concerning the management and operation of the ships and may have impact on their safety.A
SAR party and the ship in distressB
SAR authorities and the ship in distress and survival craftC
A ship station and any coast stationD
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单选题If the operating element of a thermostatic valve installed in a diesel engine cooling system malfunctions, it may result in （）A
a low level in the engine expansion tankB
excessively high coolant pressureC
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单选题What is the function of thermostatic expansion valve in a compression refrigeration system?（）A
nonexistentB
for controlling pressureC
for controlling superheatD
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单选题On a ship，the possibility of a blowout makes which type of diesel engine shutdown desirable?（）A
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单选题In a refrigeration system, foaming of the crankcase oil may cause the （）.A
expansion valve to overfeedB
compressor to knockC
water regulating valve to failD
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单选题A pressure drop through the refrigerant liquid line may cause （）.A
solenoid valve to seizeB
compressor to huntC
formation of flash gas in the liquid lineD
expansion valve to freeze open
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单选题The emergency bilge suction or bilge injection valve is used to prevent （） of the ship.A
proceedingB
overloadingC
collisionD
flooding
考题
单选题The purpose of the purge valve at the top of the condenser in a refrigerating system is to（）A
remove any air that may accumulate in the systemB
take out unpleasant fumes from the refrigerantC
vent off excess refrigerant in an emergencyD
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考题
单选题When ship in the dock repairing, engine department should emphasize on the inspection of（）A
sea valve chest, sect valve, thrusterB
bilge motherboard, steering and the shaft systemC
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NAVTEXB
EGCC
AMVERD
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单选题Which of the following statements is TRUE regarding automatic identification systems (AIS) ? （）A
AIS may be used to make passing arrangements via ship-to-ship text messaging thus relieving a vessel operator from sounding whistle signals or making contact via radiotelephoneB
AIS may be used to make passing arrangements via ship-to-ship text messaging but a vessel operator is still required to sound whistle signals unless the arrangement is made via radiotelephoneC
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AIS cannot be used to make passing arrangements because the use of the ship-to-ship text messaging feature in this way is prohibited
考题
单选题Moisture in a refrigeration system can cause （）.A
freezing the expansion valve closedB
corrosion of system pipingC
improper temperature regulationD
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考题
单选题The purpose of the delivery check valve used in a diesel fuel injection jerk pump is to （）.A
assist in a quick cutoff of fuel injectionB
allow oil backflow from the injector to the helixC
reduce fuel oil pressure between injection strokesD
meter the quantity of fuel delivered
考题
单选题To add refrigerant to the low side of an air conditioning system, the refrigerant should be introduced through the （）A
suction service valve as a vaporB
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考题
单选题To add refrigerant to the high side of an air conditioning system, you should introduce the refrigerant through the （）.A
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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Each part of the fire-main system located on an exposed deck must be（）.A
protected against freezingB
locked to prevent theftC
numbered sequentiallyD
pressurized at all times
考题
单选题In a refrigeration system, if the cooling water to the condenser fails, the（）.A
box temperature solenoid valve will closeB
expansion valve will closeC
compressor will shutdownD
king valve will open
考题
单选题General radio communications in the global system may（）ship’s safety.A
be responsible forB
have an impact onC
commandD
give a guidance to
考题
单选题To correct the condition of slugging and flooding back in a refrigeration system, it may be necessary to （）.A
re-adjust the discharge pressureB
clean the expansion valve screenC
add refrigerantD
adjust the expansion valve
考题
单选题The low pressure side of a refrigeration system is considered to exist from the （）.A
expansion valve to the compressorB
receiver to the expansion coilC
expansion valve to the evaporatorD
condenser to the expansion valve
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单选题A branch line valve of a fire extinguishing system on a ship must be marked with the（）.A
maximum pressure allowed at that branchB
name of the space or spaces which it servesC
date of the last maintenance inspectionD
pressure needed to maintain an effective stream at that point
考题
单选题A pressure drop in the liquid line of a refrigeration system may cause（）A
the solenoid valve to seizeB
the compressor to huntC
flash gas to form in the liquid lineD
the expansion valve to freeze open
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单选题Control valves of a CO2 system may be located within the protected space when（）.A
it is impractical to locate them outsideB
there is also a control valve outsideC
the CO2 cylinders are also in the spaceD
an automatic heat-sensing trip is installed
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