水压力（hydraulic pressure）
水压力（hydraulic pressure）
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
Air trapped in the hydraulic fluid of a steering system may be indicated byA.the steering pumps overspeedingB.a jammed open relief valveC.a constantly occurring improper rudder responseD.excessive ram pressure
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
The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by_______.A.large conical springsB.compressed air pressureC.hydraulic pressureD.exhaust gas pressure
What type of valve is used to direct the flow of hydraulic fluid?A.relief valveB.direction control valveC.stop valveD.pressure control valve
Hydraulic machinery failures are commonly caused by contamination of the hydraulic fluid and ______.A.fluid frictionB.fluid turbulenceC.component misalignmentD.pressure surges
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
A certificated lifeboatman assigned to command the lifeboat must ______.A.be the first individual to board the craftB.drain the hydraulic pressure before lowering the craftC.have a list of the persons assigned to the liftboatD.all of the above
单选题In a hydraulic system, （） are used to protect the system from over pressure.Astop valvesBcheck valvesCsafety valvesDreducing valves
单选题A marine diesel engine is started by（）Asupplying high pressure oil into a hydraulic motorBsupplying high temperature air into the cylinderCsupplying high pressure air into the cylinderDelectrical igniting
单选题（）can be used to prevent hydraulic system overloaded or keep the pressure of oil outlet from pump constant.AOverflow valveBReducing valveCBalancing valveDReducing valve or balancing valve
单选题Air trapped in the hydraulic fluid of a steering system may be indicated by（）Athe steering pumps overspeedingBa jammed open relief valeCa constantly occurring improper rudder responseDexcessive ram pressure
单选题In a fixed displacement axial piston hydraulic motor, the speed is varied by（）Aregulating the ratio between torque and speed via the torque limiter at the motorBdirecting the motor output flow through a bypass lineCmaintaining a constant flow and pressure inputDcontrolling the input flow rate
单选题Most hydraulic steering gears are fitted with relief valves which（）Afunction when the rudder is amidshipsBrelieve excess whip pressure from the hydraulic oil systemCprotect the piping assembly from external rudder shockDrelieve excessive telemotor pressure
单选题A reservoir, as used in hydraulic systems aboard ship, is used to store hydraulic oilAnother function is to（）Aact as a shock absorberBmaintain the stored oil under pressureCact as a base or foundation for the power unitDeliminate pressure surges in the system
单选题If a hydraulic pump is overheating, the cause may be （）.Aexcessive internal leakage in the pumpBlow discharge pressure and fluid flowCexcessive fluid level in the hydraulic reservoirDoperation of the pump at 100% efficiency
单选题After installing a new hydraulic pump in a system, what special attention should be given to the hydraulic system?（）AThe relief valves in the system should be readjustedBThe filters and strainers should be checked frequentlyCAll system pressure should be readjustedDThe system should be drained and renewed with a fluid of different operating characteristics
单选题Flexible hose under pressure in a hydraulic system will （）.Atend to twist about its long axisBexpand in length and in diameterCcontract in length and expand in diameterDflex at right angles to the applied pressure
单选题Pressure in an operating hydraulic system is developed （）.Aonly by the pump as its primary functionBby resistance to the fluid flow through the systemCby the thermal input to the systems fluidDsolely by the charge applied by the accumulators
单选题A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by （）.Athe four-way control valve failing to shiftBthe bleeder valve sticking in the open positionCcold hydraulic fluidDa clogged air vent falter on the oil reservoir
单选题The device used to store a charged pressure for a hydraulic starting system is called the（）AreservoirBhand pumpCacceleratorDaccumulator
单选题Which of the following hydraulic systems is not one of the three sub-division of the Hydraulic drive system?（）AConstant pressure systemBVariable pressure systemCVariable displacement systemDConstant volume system
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（）.Acause loss of hydraulic oil from the systemBresult in extreme damage to the pumpCcause damage to the pump ff not continually drained from the pump casingDresult in the system high side pressure to substantially drop off
单选题Hydraulic machinery failures are commonly caused by misalignment of the system components and by （）.Ahydraulic fluid contaminationBexcessive fluid frictionCturbulent fluid flowDfluid pressure surges
单选题Which of the listed pressure control valves would be used to establish the maximum operating pressure of a hydraulic system?（）APressure-reducing valveBUnloading valveCCounterbalance valveDPressure-relief valve