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
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
相关考题：
Which of the listed pressure control valves would be used to establish the maximum operating pressure of a hydraulic system?A.Pressure-reducing valveB.Unloading valveC.Counterbalance valveD.Pressure-relief valve
Before doing any work on a hydraulic system equipped with accumulators, you shouldA.drain the accumulators and purge with oxygenB.bleed off all stored energy from the accumulators completelyC.charge the accumulators to prevent system energy lossD.pump the hydraulic fluid into the accumulators to prevent fluid loss
After installing a new hydraulic pump in a system, what special attention should be given to the hydraulic system?A.The relief valves in the system should be readjustedB.The filters and strainers should be checked frequentlyC.All system pressure should be readjustedD.The system should be drained and renewed with a fluid of different operating characteristics
Before performing any maintenance on a hydraulic system storing energy in an accumulator, you shouldA.pressurize the system to test for leaksB.bleed off all pressure within the systemC.operate the machine until it reaches normal temperatureD.disconnect the pump pressure control switch
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