更多"When operating the air supply syste"的相关试题:
[单项选择]In reference to air conditioning, when air attains the maximum amount of moisture it can hold at a specific temperature, it is said to be （）.
A. superheated
B. saturated
C. condensed
D. convected
[单项选择]When air becomes trapped in the hydraulic fluid of a steering system, the （）.
A. rudder will respond sluggishly
B. hydraulic rams will over-speed
C. sight glass will show bubbles
D. ram relief valves will lift
[单项选择]The fuel supply system to an automatic auxiliary boiler, will be automatically shutdown if the boiler （）
A. salinity is abnormally high
B. steam demand is too high
C. water level is abnormally low
D. feedwater flow is low
[单项选择]The fuel oil supply system to an automatic auxiliary boiler, will automatically shutdown if the boiler （）
A. steam demand is high
B. salinity is high
C. safety valve simmers
D. burner flame is extinguished
[单项选择]When air is at its dew point it（）.
A. will contain no additional moisture
B. has the lowest relative humidity
C. cannot keep up its moisture
D. has a low absolute humidity
[单项选择]When air is at its dew point it is at its（）
A. lowest absolute humidity
B. lowest relative humidity
C. highest absolute humidity
D. highest relative humidity
[单项选择]A major advantage of the NAVTEX system when compared to other systems is that（）.
A. the information can be received on an ordinary FM radio
B. warnings are printed out for reading when convenient
C. broadcasts are at scheduled times
D. a low frequency band is used for long distance transmission
[单项选择]If an air compressor is used to supply air primarily to the combustion control system and other pneumatic controllers, the entire system is known as the （）.
A. control air system
B. forced draft air system
C. supply air system
D. ships service air system
[单项选择]Fog forms when the air（）.
A. Is 50% water saturated
B. Is 90% water saturated
C. Temperature is greater than the dew point temperature
D. Temperature is equal to，or below the dew point temperature
[单项选择]Air entering an air-cooled refrigeration system is indicated by （）.
A. frosting of the liquid line
B. higher than normal head pressure
C. a clear sight glass
D. abnormally cold reefer boxes
[单项选择]When the air charge contacts with the cylinders and pistons and mixes with the residual gases, it will（）
A. increase in temperature
B. lose its energy partly
C. expand and do work
D. begin to be compressed
[单项选择]When starting air is admitted, a diesel engine turns over very slowly without firingThe cause may be （）
A. an obstruction in an cylinder
B. water accumulation in some engine cylinders
C. low starting air pressure
D. low scavenge air pressure
[单项选择]
When starting air-conditioner in the winter, we should open（）in sequence.
Ⅰ.alve of warming
Ⅱ.alve of humidifier
Ⅲ.an
A. Ⅲ-Ⅱ-Ⅰ
B. Ⅲ-Ⅰ-Ⅱ
C. Ⅰ-Ⅲ-Ⅱ
D. Ⅱ-Ⅲ-Ⅰ
[单项选择]The unloading system on an air compressor will （）.
A. increase compressor discharge pressure on demand
B. increase compressor operating speed as necessary
C. allow the motor to turn the compressor opposed only by friction
D. reduce the compressor frictional load when starting
[单项选择]What occurs when rising air cools the dew point?（）
A. advection fog forms
B. humidity decrease
C. wind increase
D. Cloud form
[单项选择]When an air started, four-stroke/cycle diesel engine is being cranked, the starting air is admitted to each cylinder during what would normally be the（）
A. intake stroke
B. compression stroke
C. power stroke
D. exhaust stroke
[单项选择]When the starting air valve closes on one cylinder, another starting air valve has （） opened on another cylinder whose piston has just commenced its downward stroke.
A. just
B. nearly
C. merely
D. already
