更多"When a vacuum boiling evaporator wo"的相关试题:
[单项选择]With a vacuum boiling evaporator, the remainder of sea water fed to the evaporator is pumped out by （）.
A. a brine pump
B. an air ejector
C. a feed pump
D. distillate pump
[单项选择]In a vacuum boiling evaporator, the fresh water generated is pumped out by （）.
A. a brine pump
B. an air ejector
C. a feed water pump
D. a condensate pump
[单项选择]The hydraulic oil most likely to thin out when hot and thick when cold would have a viscosity index of（）
A. 20
B. 40
C. 60
D. 80
[单项选择]You are operating a lift boat.When beginning to jack down you should（）.
A. Jack down one leg at a time
B. Jack up first，then down
C. Undog doors to the engine room
D. Assemble all personnel on the main deck
[单项选择]VACUUM GENERATOR的工作条件（）
A. 在地面或空中低于16000英尺
B. 仅在地面
C. 仅在空中低于16000英尺
D. 飞机高度高于16000FT
[单项选择]The vacuum maintained in the salt water feed heater shell of a flash-type evaporator is generally accomplished by （）.
A. a separate air ejector unit
B. a direct unimpeded connection between second stage and salt water feed heater
C. either by vacuum drag or an external line from the first stage via a fixed orifice
D. the fixed orifice provided in the steam supply line
[单项选择]A vacuum is initially established in the first and second stages of a low pressure evaporator by the use of （）
A. vacuum drag from the auxiliary condensate system
B. individual vacuum pumps
C. a single non-condensing air ejector
D. a two stage air ejector
[单项选择]What is the purpose of pressure-vacuum relief valves? （）
A. Regulation of discharge pressure from cargo pumps
B. Maintaining constant velocity in cargo lines
C. Regulation of suction head on cargo pumps
D. To maintain a tank or void at atmospheric pressure
[单项选择]A vacuum is initially created in a flash type distilling plant by（）.
A. the flashing of the feed water
B. the condensation of the saltwater feed
C. air ejectors, eductors, or a separate vacuum pump
D. condensation of the distillate
[单项选择]What is TRUE of pressure/vacuum valves? （）
A. They are designed to provide for the flow of small volumes of tank atmospheres caused by thermal variations in a cargo tank
B. They should operate in advance of the pressure/vacuum breakers
C. They should be kept in good working order by regular inspection and cleaning
D. All of the above
[单项选择]In a vacuum distillation system, the case is the higher the pressure, （）.
A. the saturation temperature is higher
B. the higher the saturation temperature
C. the higher is the saturation temperature
D. the saturation temperature is more high
[单项选择]Because of the reduced （） in the vacuum boiling evaporator, some of the sea water boils as it flows through the tubes.
A. temperature
B. water level
C. pressure
D. rate of flow
[单项选择]If a bilge pump is able to develop vacuum, but is unable to sufficiently pump out the bilges, you would check for all of the following EXCEPT （）.
A. the circuit breaker
B. for leaks in the suction piping
C. relief valve is not properly seated
D. the suction strainer
[单项选择]When can routine communications be resumed when radio silence has been imposed?（）
A. After determining that the frequency or channel appears to be no longer in use
B. After determining that geographic distance from the distress situation will prohibit any other signal from interfering with emergency communications
C. Routine communications can resume after the Rescue Coordination Center transmits a message on the frequency or channel being used for emergency communications stating that such traffic has concluded
D. If，in the Master's opinion，communications on that frequency will interfere with emergency communications
[单项选择]Hot gas defrosting uses the hot gas from （） to defrost the evaporator.
A. starting air bottles
B. diesel engines
C. boilers
D. refrigeration compressors
[单项选择]Fresh water is used for the cooling of cylinder jackets and （） of the marine diesel engine.
A. cylinder covers
B. lubricating space
C. crosshead
D. exhaust manifold
[单项选择]When the（）is large, the ship is stiff; and when it is small, she is tender.
A. GM
B. free surface
C. longitudinal center of gravity
D. transverse center of gravity
