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）
The amount of fluid delivered by a positive displacement pump can be regulated by _____.
A.throttling the pressure line
B.changing the speed of the driving rotor
C.either A or B
D.None of the above is tree
参考答案
更多 “ The amount of fluid delivered by a positive displacement pump can be regulated by _____.A.throttling the pressure lineB.changing the speed of the driving rotorC.either A or BD.None of the above is tree ” 相关考题
考题
Overheating of the hydraulic fluid in an electro-hydraulic anchor windlass can result from a/an( ).A.overload on the pump motorB.low fluid level in the reservoirC.low fluid viscosity around the shaft sealD.high oil level in the sump
考题
Which statement is NOT true?A.While displacement pump works, volume of the working chamber will increase and decrease alternatelyB.A gear pump always has two gearsC.Any vane pump will have a rotor within a ringD.A balanced vane pump has two outlet ports and they are positioned symmetrically
考题
The pressure of a liquid leaving the pump can be referred to as the ______.A.total headB.discharge headC.net positive suction headD.suction head
考题
The amount of fuel delivered by a helical plunger fuel injection pump is controlled by ______.A.varying the pump discharge pressureB.varying the pump return pressureC.rotation of the pump plungerD.rotation of the pump barrel
考题
单选题A positive displacement pump is that where the volume of the pump chamber is alternately increased to （） and then decreased to （）.A
draw the liquid in；force the liquid outB
force the liquid out；draw the liquid inC
suction；drawD
deliver；outlet
考题
单选题A screw pump belongs to （） according to its working principle.A
reciprocating pumpsB
positive displacement pumpsC
centrifugal pumpsD
centripetal pumps
考题
单选题Gear pumps are of positive displacement type pumps because they discharge a near constant amount of liquid （） pressure.A
depending onB
in relative toC
regardless ofD
because of
考题
单选题A variable displacement system of hydraulic drives consists of （）.A
a variable displacement axial piston pumpB
a constant displacement axial piston pumpC
a reciprocating piston pumpD
a centrifugal pump
考题
单选题Which of the following statements about pump operations is NOT a correct statement?（）A
In order for a fluid to be pumped, a fluid must be made to flowB
A substance must be cold in order for it to be pumpedC
The kinetic energy imparted by the pump can be used to force a liquid through a hydraulic systemD
A pump must receive its energy from an external source
考题
单选题Gear pumps are （） because they discharge a near constant amount of liquid regardless of pressure.A
negative displacement typeB
turbine typeC
positive displacement typeD
mixed-flow type
考题
单选题Which of the listed pumps is NOT a positive displacement pump?（）A
CentrifugalB
ReciprocatingC
GearD
Rotary
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The pump has a constant stroke and the amount of fuel delivered is regulated by rotating （） which has a specially arranged helical groove cut into it.A
the pump cylinderB
the pump camC
the pump plungerD
the pump miler
考题
单选题A positive displacement pump is that where the volume of the pump chamber is alternately （） to draw the liquid in and then （） to force the liquid out.A
increased；decreasedB
decreased；increasedC
decreased；decreasedD
increased；increased
考题
单选题If a radial piston hydraulic pump fails to deliver rated fluid volume, the cause can be （）.A
contaminated fluidB
pitted thrust ringsC
worn pintle bearingsD
obstructed suctions passage
考题
单选题In a diesel engine, a positive displacement type blower is usually （）A
gear drive by the engineB
driven by an exhaust gas turbineC
driven by a camshaftD
driven by separate motor
考题
单选题The amount of fluid delivered by a gear pump can be regulated by （）.A
throttling the pressure lineB
changing the speed of the rotorC
either A or BD
None of the above is true
考题
单选题The quantity of oil injected into the cylinder can be regulated （）.A
by turning the pump plungerB
by vary the fuel valve spring forceC
by no means by controlling the governorD
by enlarging or diminishing the injection hole
考题
单选题The output volume of a positive fixed displacement pump can be changed only by （）.A
changing the angle of the tilting plateB
changing the speed of the pumpC
moving the slide block and rotorD
moving the shaft trunnion block
考题
单选题Which of the following statements is/are true regarding hydraulic pumps in general? （）A
Variable volumes can be obtained with gear pumps only by variation of the pump drive speedB
A radial piston pump houses sliding pistons in a stationary cylinder block through which passes a rotating pintle or ported shaftC
The amount of fluid displaced per revolution of an axial piston rotary pump is dependent on the angle formed between the cylinder block and valve plateD
All of the above
考题
单选题In a radial piston pump, reversal and control of fluid flow are accomplished by moving the （）.A
central valveB
radial plungerC
floating ringD
cylinder body
考题
单选题The pressure of a liquid leaving the pump can be referred to as the （）.A
total headB
discharge headC
net positive suction headD
suction head
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The amount of fluid delivered by a positive displacement pump can be regulated by （）.A
throttling the pressure lineB
changing the speed of the driving rotorC
either A or BD
None of the above is tree
考题
单选题Which of the listed conditions can lead to cavitation气穴in a centrifugal pump?（）A
Vapor pockets formed in the suction flow streamB
Rough easing volute surfacesC
Worn wearing ringsD
Heavy fluid in the flow stream
考题
单选题The amount of fuel delivered by a helical plunger fuel injection pump is controlled by （）A
varying the pump discharge pressureB
varying the pump return pressureC
rotation of the pump plungerD
rotation of the pump barrel
考题
单选题The pressure head of a pump is given in the unit of （）.A
kgB
MPaC
meter fluid columnD
None of the above is true
热门标签
最新试卷
