网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
单选题
When normal operating pressure is applied to the hydraulic oil used in a high-pressure system, the oil （）.
A
viscosity will decrease
B
volume will increase
C
volume will decrease
D
pour point will be reduced
参考答案
参考解析
解析：
暂无解析
更多 “单选题When normal operating pressure is applied to the hydraulic oil used in a high-pressure system, the oil （）.A viscosity will decreaseB volume will increaseC volume will decreaseD pour point will be reduced” 相关考题
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
考题
When using a fuel with a higher than normal sulfur content in an auxiliary four stroke diesel engine, you mayA.maintain higher than normal jacket water temperatureB.change the lube oil more frequently than normalC.maintain a higher air-box temperature than normalD.maintain a higher air-box pressure than normal
考题
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
考题
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
考题
If the suction pressure for an operating refrigeration compressor is below normal, the cause may be ______.A.an excess of liquid refrigerantB.the expansion valve overfeedingC.a fouled compressor suction strainerD.the compressor short cycling
考题
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
考题
单选题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
考题
单选题Overheating of a hydraulic system may be a result of （）.A
changing pump discharge pressure in response to normal load variationsB
a high oil levelC
incorrect fluid viscosityD
continued slow re-circulation of the oil
考题
单选题Adjustments to the compensating needle valve in a hydraulic governor should be made with the engine at （）A
maximum power at a normal loadB
maximum power and load under normal conditionsC
half speed and normal temperatureD
normal operating temperature without a load
考题
单选题Pressure 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 systems fluidD
solely by the charge applied by the accumulators
考题
单选题To avoid excessive surge pressure when bunkering, you should （）A
bunker at a normal rateB
check for kinks in hoseC
close valves slowlyD
shut valves before topping off
考题
单选题Most hydraulic steering gears are fitted with relief valves which（）A
function when the rudder is amidshipsB
relieve excess whip pressure from the hydraulic oil systemC
protect the piping assembly from external rudder shockD
relieve excessive telemotor pressure
考题
单选题Late fuel injection timing is indicated by （）A
lower than normal cylinder pressure and low exhaust temperatureB
lower than normal cylinder pressure and high exhaust temperatureC
higher than normal cylinder pressure and low exhaust temperatureD
higher than normal cylinder pressure and high exhaust temperature
考题
单选题Which of the following hydraulic systems is not one of the three sub-division of the Hydraulic drive system?（）A
Constant pressure systemB
Variable pressure systemC
Variable displacement systemD
Constant volume system
考题
单选题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
考题
单选题Hydraulically, servo-operated, automatic, change over valves, utilized in a two ram hydraulic steering gear, serve to（）A
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
考题
单选题The knock occurring when a cold diesel engine is started and continues while running at low speed, but stops when the engine reaches normal operating speed and temperature, is（）.A
caused by retarded injection timingB
caused by a mechanical defect in one cylinderC
caused by high fuel injection pressuresD
normal for these conditions
考题
单选题Sluggish response or action of the hydraulic actuators may be a result of （）.A
insufficient loadB
excessively high oil viscosityC
relief-valve pressure setting too highD
reservoir level being maintained two inches above normal
考题
单选题When the boiler load returns to normal, the drum pressure will rise and steam bubble formation will reduce, causing a fall in water level This is known as （）.A
swellB
shrinkageC
flash offD
lack of water
考题
单选题Which one is not the normal operation for boiler shutdown?（）A
Carry out soot blowing if permissibleB
Change fuel supply to diesel oilC
Close steam stop valves on boiler when pressure is reducedD
Drain boiler empty when it has cooled down
考题
单选题Under normal operating conditions, the highest temperature and pressure conditions existing in a flash-type evaporator will occur in the （）.A
first stageB
second stageC
distillate coolerD
salt water feed heater
考题
单选题A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by （）.A
the four-way control valve failing to shiftB
the bleeder valve sticking in the open positionC
cold hydraulic fluidD
a clogged air vent falter on the oil reservoir
考题
单选题Flexible hose under pressure in a hydraulic system will （）.A
tend to twist about its long axisB
expand in length and in diameterC
contract in length and expand in diameterD
flex at right angles to the applied pressure
考题
单选题When attempting to restart a warm high-speed engine, which of the following reactions can you expect?（）A
Excessive fuelB
Higher than normal temperatures for star upC
Longer starting periodsD
Higher than normal lube oil pressure
考题
单选题When using a fuel with a higher than normal sulfur content in an auxiliary diesel engine, you should（）A
maintain higher than normal jacket water temperatureB
change the lube oil more frequently than normalC
maintain a higher air-box temperature than normalD
maintain a higher air-box pressure than normal
考题
单选题The single acting cylinder is the simplest form where pressure is applied to the full area of the piston head to move the load through piston rod extensionThe load causes rod （） when the drive pressure is released.A
contractionB
retractionC
expansionD
shrinkage
热门标签
最新试卷