更多"A knocking sound emitted from an un"的相关试题:
[单项选择]When approaching Block Island Sound from Long Island Sound，you will enter waters governed by the International Rules of the Road when you（）.
A. pass through The Race
B. cross the territorial sea boundary
C. exit Block Island Sound to the east or south
D. None of the above，as Long Island Sound is governed by the International Rules of the Road
[单项选择]A knocking sound from one cylinder of an operating air compressor indicates （）.
A. a defective or broken high pressure un-loader
B. a loose valve plate
C. excessive overload
D. no compression
[单项选择]The loss of （） from an air compressor could lead to an overheated air discharge and possibly an explosion in the pipelines leading to the air reservoir.
A. lubricating oil
B. compressed air
C. cooling water
D. sealing ring
[单项选择]Bad valves operation of the reciprocating air compressors can be detected by observation of （）.
A. the discharge temperature low
B. the discharge temperature high
C. the discharge pressure rise
D. the inter-stage pressure low
[单项选择]Air compressor cylinder un-loaders enable the compressor to （）.
A. vary their speed according to temperature and load
B. start and come up to speed before air compression begins
C. change speed according to overload demands
D. reduce compressed air charge density
[单项选择]Air blowing from the intake air filter of an operating air compressor indicates （）.
A. broken inlet valves
B. broken discharge valves
C. pulsations in the air distribution system
D. overloading of the air distribution system
[单项选择]The process of removing moisture from air is known as（）.
A. humidification
B. dehumidification
C. vaporization
D. evaporation
[单项选择]The engine is started with （） supplied from air receivers.
A. pressure oil
B. pressure water
C. compressed air
D. cooling water
[单项选择]In order to properly remove air from the casing of a centrifugal pump when starting, the pump should have a （）.
A. positive head
B. negative suction head
C. mechanical seal
D. vent valve attached to the casing at the top of the volute
[单项选择]（） device is provided to prevent starting air from being admitted to the cylinder before the reversing is completed.
A. An automatic
B. A transmission
C. A self-regulating
D. An interlocking
[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]Air or noncondensable gas is removed from a refrigeration system by a （）
A. separating chamber
B. system of baffles
C. purge valve
D. vacuum reducing valve
[单项选择]The purging of air from an elector-hydraulic steering gear unit is necessary when（）
A. changing over to hand pump operation
B. engaging the trick wheel
C. the system has been filled with new oil
D. the rudder angle indicator does not match the helm position
[判断题]上行CoMP和下行CoMP的实现都依赖于终端。
[单项选择]A yellow signal floating in the air from a small parachute，about 300 feet above the water，would indicate that a submarine（）.
A. has fired a torpedo during a drill
B. is about to rise to periscope depth
C. is on the bottom in distress
D. is disabled and unable to surface
[单项选择]Intake air flow from a diesel engine turbocharger is directly proportional to engine（）
A. exhaust gas pressure
B. exhaust gas temperature
C. speed
D. load
[单项选择]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
[单项选择]A yellow signal，floating in the air from a parachute，about 300 feet above the water，indicates that a submarine（）.
A. will be coming to periscope depth
B. will be coming to the surface
C. is on the bottom in distress
D. is in distress and will try to surface
