更多"A hydraulic motor may be driven by "的相关试题:
[单项选择]The rotor of the hydraulic motor rotates at a speed proportional to the （）.
A. flow of oil
B. pressure of oil
C. A and B
D. temperature of oil
[单项选择]Overheating of a hydraulic system may be a result of （）.
A. changing pump discharge pressure in response to normal load variations
B. a high oil level
C. incorrect fluid viscosity
D. continued slow re-circulation of the oil
[单项选择]If an electric motor driven air compressor fails to start, it may be due to a （）.
A. leaking discharge valve
B. jammed suction valve
C. tripped overload relay
D. broken discharge un-loader
[单项选择]If a hydraulic pump is overheating, the cause may be （）.
A. excessive internal leakage in the pump
B. low discharge pressure and fluid flow
C. excessive fluid level in the hydraulic reservoir
D. operation of the pump at 100% efficiency
[单项选择]If a DC motor runs hot, the cause may be （）
A. high mica condition
B. low ambient temperature
C. clogged ventilation ducts
D. an open in the shunt field
[单项选择]If one hydraulic pump of an electro-hydraulic steering unit falls, the vessels steering can be initially and best maintained by using the （）.
A. trick wheel
B. accumulator
C. standby pump
D. telemotor
[单项选择]External and internal leakage in hydraulic systems may be caused by （）.
A. unusual vibration
B. excessive worn parts
C. abnormal pressure
D. any of the above
[单项选择]The most common contaminate of governor hydraulic fluid is （）.
A. moisture
B. dirt
C. acid
D. air
[单项选择]Hydraulic machinery failures are commonly caused by misalignment of the system components and by （）.
A. hydraulic fluid contamination
B. excessive fluid friction
C. turbulent fluid flow
D. fluid pressure surges
[单项选择]A variable displacement system of hydraulic drives consists of （）.
A. a variable displacement axial piston pump
B. a constant displacement axial piston pump
C. a reciprocating piston pump
D. a centrifugal pump
[单项选择]Overload protection on hydraulic system is provided by the use of （）.
A. stop valves
B. pressure relief valves
C. balance valves
D. regulating speed valves
[单项选择]The function of the hydraulic telemotor transmitter used in an electro-hydraulic steering gear system is to （）.
A. transmit the rudder angle to the bridge indicator
B. prevent the control linkage from striking the stops when hard over
C. automatically purge all entrained air from the system
D. send hydraulic signals to the receiving unit
[单项选择]The required rudder angle is transmitted hydraulically or electrically from the steering wheel at the bridge to the （）at the steering gear, just above the rudder.
A. transmitter
B. tele-motor
C. hydraulic ram
D. hydraulic cylinder
[单项选择]An electrically driven automatically operating auxiliary blower is provided for slow speed and （） of a low speed diesel engine.
A. manoeuvring operations
B. bad combustion
C. cooling
D. mooring trial
[单项选择]Sluggish response or action of the hydraulic actuators may be a result of （）.
A. insufficient load
B. excessively high oil viscosity
C. relief-valve pressure setting too high
D. reservoir level being maintained two inches above normal
[单项选择]Most hydraulic steering gears are fitted with relief valves which（）
A. function when the rudder is amidships
B. relieve excess whip pressure from the hydraulic oil system
C. protect the piping assembly from external rudder shock
D. relieve excessive telemotor pressure
[单项选择]Hydraulic pumps most commonly used in steering systems are of the （）.
A. lobe type
B. screw type
C. axial piston type
D. volute type
[单项选择]Dual electro-hydraulic steering units usually operate （）.
A. with both pumps on line at the same time
B. with one pump on standby
C. with the follow-up gear disconnected
D. only when the rudder is moved amidships
