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单选题
As for a hydraulic single action vane pump, the inner wall of the stator is usually of （） shape.
A
circular
B
elliptical
C
rectangular
D
hexagon
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更多 “单选题As for a hydraulic single action vane pump, the inner wall of the stator is usually of （） shape.A circularB ellipticalC rectangularD hexagon” 相关考题
考题
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考题
Which statement is NOT true?A.In a simple vane pump, the rotor and cam ring are exactly concentricB.Balanced vane pump has an elliptical cam ringC.Liquid in both gear pump and vane pump are forced out to the outlet.D.Balanced vane pumps can work at a higher pressure than the simple vane pump
考题
Leakage of hydraulic fluid from around the shaft of a hydraulic motor may be caused by ______.A.permanent loss of pump suctionB.worn shaft sealsC.high level in the oil sumpD.low motor RPM
考题
If one hydraulic pump of an electro-hydraulic steering unit fails, the vessel’s steering can be initially and best maintained by using the ______.A.trick wheelB.accumulatorC.standby pumpD.Telemotor
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单选题When the desired rudder angle is attained by a typical double mm electro-hydraulic steering gear,the（）.A
ram relief valves bypass oil to stop rudder movementB
six-way valve shifts to the neutral flow positionC
steering pump electric motor is de - energized by the transfer switchD
follow-up gear takes the hydraulic pump off stroke
考题
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The six-way valve opensB
The steering service pump motor is stoppedC
The follow-up gear takes the pump off strokeD
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考题
单选题If the pump for a hydraulic anchor windlass is overheating, the cause may be （）.A
excessive drive motor speedB
excessive pump discharge pressureC
too low of a tilting box angleD
insufficient drive motor speed
考题
单选题The function of a centrifugal pump double volute casing is to （）.A
reduce radial thrust to the impellerB
double the liquid velocity through the pump when compared to a single voluteC
reduce hydraulic end thrustD
provide the effect of multi-staging
考题
单选题Prior to running the hydraulic pump, examine the system carefully and ensure that the lever of control valves is in （） position.A
neutralB
endC
openingD
closure
考题
单选题It is important with all hydraulic systems to ensure that interlocking arrangements provided for pump or motor control levers are （） before the pump driving motor can be started.A
in the pert positionB
in the starboard positionC
in the neutral positionD
to be dismantled
考题
单选题If a hydraulic pump is overheating, the cause may be （）.A
excessive internal leakage in the pumpB
low discharge pressure and fluid flowC
excessive fluid level in the hydraulic reservoirD
operation of the pump at 100% efficiency
考题
单选题Cooling water pumps driven by direct reversing diesel engines are usually of the straight impeller vane type pump with a concentric housing to（）A
facilitate bi-directional operationB
provide the greatest pump efficiencyC
prevent pump clogging from marine growthD
prevent cavitation at the pump outlet
考题
单选题Leakage of hydraulic fluid from around the shaft of a hydraulic motor may be caused by（）A
permanent loss of pump suctionB
worn shaft sealsC
high level in the oil sumpD
low motor RPM
考题
单选题After stopping oily water separator, sea water should be permitted for （） minutes,（）should be closed after stopping pump to reduce oxidation corrosion of inner wall.A
15；inlet valueB
15；inlet and outlet valueC
30；inlet valueD
30；inlet and outlet value
考题
单选题The most suitable pump for oily water separator feed duties is （）.A
a reciprocating pumpB
a vane pumpC
a centrifugal pumpD
a triple screw pump
考题
单选题Because the flow rate of supply water pump is too large, oily water separator does not work wellWhich of the following is not the reason?（）A
the monitoring equipment is out of orderB
separating effect becomes badC
inner wall is contaminatedD
separating effect becomes bad and inner wall is contaminated
考题
单选题The delivery rate of a variable stroke axial piston hydraulic pump is controlled by varying the position of the （）.A
slide blockB
tilting boxC
pintleD
reaction ring
考题
单选题When a hydraulic vane pump is working, which of the following is in contact with the vanes?（） (1) the rotor (2) the internal surface of the housing (3) the external surface of the housingA
(1) onlyB
(2) onlyC
(1) and (2)D
(1), (2) and (3)
考题
单选题An axial piston, variable stroke pump is used in a vessels hydraulic steering gearUnder pressure, oil continually leaks out from between the valve plate/cylinder barrel and will（）.A
cause loss of hydraulic oil from the systemB
result in extreme damage to the pumpC
cause damage to the pump ff not continually drained from the pump casingD
result in the system high side pressure to substantially drop off
考题
单选题If the pump for a hydraulic anchor windlass is over heating, the cause may be （）.A
increased pump speedB
excessive pump discharge pressureC
too low of a tilting box angleD
low pump speed
考题
单选题As for a hydraulic vane pump, which of the following is in contact with the vanes during working: （） (1)the rotor (2)the pump shaft (3)the external surface of the housingA
(1) onlyB
(2) onlyC
(1) and (2)D
(1),(2)and(3)
考题
单选题A vane pump belongs to （） according to its working principle.A
reciprocating pumpB
positive displacement pumpC
centrifugal pumpD
centripetal pump
考题
单选题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 wheelB
accumulatorC
standby pumpD
telemotor
考题
单选题If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be （）.A
a low load on the unitB
a clogged pump suction strainerC
a blockage in the line between the pump and hydraulic motorD
the hydraulic motor turning too fast
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