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Pressure drop 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 system's fluid
D.solely(单独地) by the charge applied by the accumulators
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更多 “ Pressure drop in an operating hydraulic system is developed ______.A.only by the pump as its primary functionB.by resistance to the fluid flow through the systemC.by the thermal input to the system's fluidD.solely(单独地) by the charge applied by the accumulators ” 相关考题
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Unloading valveC
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an improper rudder responseC
bubbles in the sight glassD
ram relief valves lifting
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incorrect fluid viscosityD
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by the thermal input to the systems fluidD
solely by the charge applied by the accumulators
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Variable pressure systemC
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maintain the stored oil under pressureC
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eliminate pressure surges in the system
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neutralB
endC
openingD
closure
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The relief valves in the system should be readjustedB
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stop valvesB
check valvesC
safety valvesD
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allow an alternate main pump to start in the fully loaded condition thus developing immediate full torqueB
prevent either main pump from being hydraulically motored when idle by cross pressure flowC
prevent both units from operating simultaneously which could result in doubling the flow of oil and pressure leading to over pressurization of the systemD
all of the above
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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
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protect the compressor from low discharge pressureC
start and stop the compressor upon system demandD
start the compressor after a drop in the evaporator pressure
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cold hydraulic fluidD
a clogged air vent falter on the oil reservoir
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tend to twist about its long axisB
expand in length and in diameterC
contract in length and expand in diameterD
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openB
closeC
drainD
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result in extreme damage to the pumpC
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controllerB
governorC
instrumentD
apparatus
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a clogged pump suction strainerC
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the hydraulic motor turning too fast
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hydraulic fluid contaminationB
excessive fluid frictionC
turbulent fluid flowD
fluid pressure surges
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