更多"In comparison to electric power，hyd"的相关试题:
[单项选择]（） is used to produce electric power.
A. An alternator
B. fresh water generator
C. A compressor
D. A clarifier
[单项选择]A power failure in the hydraulic system of a compact type steering gear would cause the rudder to（）
A. swing 35°right or left
B. remain locked in its last position
C. move to the mid-ship position automatically
D. jam against the rudder emergency stops
[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]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
[单项选择]Pressure in an operating hydraulic system is developed （）.
A. only by the pump as its primary function
B. by resistance to the fluid flow through the system
C. by the thermal input to the systems fluid
D. solely by the charge applied by the accumulators
[单项选择]In a fixed displacement axial piston hydraulic motor, the speed is varied by（）
A. regulating the ratio between torque and speed via the torque limiter at the motor
B. directing the motor output flow through a bypass line
C. maintaining a constant flow and pressure input
D. controlling the input flow rate
[单项选择]Water allowed to accumulate in the hydraulic system oil will cause an oxidation process producing by- products which are normally （）.
A. gums, acids, and varnishes
B. removed by cellulose type filters
C. neutralized by oil additives
D. not removed by absorbent filters
[单项选择]Flexible hose under pressure in a hydraulic system will （）.
A. tend to twist about its long axis
B. expand in length and in diameter
C. contract in length and expand in diameter
D. flex at right angles to the applied pressure
