更多"Low pressure air is usually taken t"的相关试题:
[单项选择]The pressure of pilot air is usually （） than that of starting air.
A. higher
B. lower
C. low
D. high
[单项选择]The fresh air coming in through the inner air ports, is compressed by（） to a higher pressure.
A. the cylinder head
B. the cross-head
C. the moving piston
D. the stationary piston
[单项选择]As the air passes through the charge air cooler, its temperature may be reduced and moisture condensed, with the condensate in danger of being carried into the engineSo a water separator should be mounted beneath the bottom part of the engine inlet manifoldA water separator is used in order to （）.
A. keep the air from being carried into the engine
B. keep the moisture from being condensed
C. keep the danger from being carded into the engine
D. take away the condensate from the air
[单项选择]Excessively low air pressure occurring in the intercooler of a reciprocating air compressor is caused by（）.
A. leaky discharge valves on the LP cylinder
B. leaky discharge valves on the HP cylinder
C. insufficient intercooler cooling
D. low ambient air pressure
[单项选择]If a weather bulletin shows the center of a low pressure system to be 100 miles due east of you，what winds can you expect in the Southern Hemisphere?（）.
A. South-southwesterly
B. North-northwesterly
C. South-southeasterly
D. North-northeasterly
[单项选择]The air required for combustion is taken from the engine room through a filter fitted on the turbochargerThis reduces the risk for too and contamination of the combustion air（）
A. high temperatures
B. low temperatures
C. wet
D. dirty
[单项选择]Starting air for auxiliary engines may be taken directly from the main reservoirs or through （）.
A. an auxiliary reservoir
B. a controlling air bottle
C. an emergency air compressor
D. a main air compressor
[单项选择]Diesel engines obtain combustion air through turbo chargers，blowers，or（）.
A. air starters
B. carburetors
C. natural aspiration
D. air receivers
[单项选择]Higher than normal temperature air passing through the intake of a diesel engine will result in（）
A. greater overall efficiency
B. greater fuel economy
C. lower horsepower
D. lower compression ratio
[单项选择]On small, low pressure, air compressors, the cylinders are usually lubricated by the （）.
A. splash method
B. mechanical force feed lubricators
C. detached sump method
D. internal cooling passages in the crankshafts and connecting rods
[单项选择]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 vapor
B. suction service valve as a liquid
C. discharge service valve as a vapor
D. charging valve as a liquid
[单项选择]In an air conditioning system, low head pressure associated with a reciprocating compressor can be the result of （）
A. broken valve springs
B. tight drive belts
C. high line voltage
D. air in the system
[单项选择]Air receivers installed in starting air systems are to be （）.
A. cylindrical in shape with service connections located at the top and bottom
B. opened and made available for inspection during biannual inspections provided
C. with automatic drain traps for the removal of moisture
D. so installed as to make the drain connections effective under extreme conditions of trim
[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]Compressed air is supplied by air compression to （）.
A. the air receivers
B. the starting valves
C. the cylinder covers
D. the distributors
[单项选择]Air line lubricators are used in compressed air systems to lubricate （）.
A. the suction and discharge valves
B. tools and equipment served by compressed air
C. air line reducing valves
D. all of the above
[单项选择]Air conditioning is the process of treating air to control （） its temperature, humidity, cleanliness and distribution to meet the comfort requirements of the occupants of the conditioned space.
A. instantaneous
B. instantaneously
C. simultaneous
D. simultaneously
[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]The quantity of cooled air delivered by an air conditioning unit should （） the sum of the quantity of air re-circulated to the unit and the quantity mechanically exhausted.
A. balance
B. not balance
C. be more than
D. be less than
