411.Pumping of a corrosive liquid is generally preferred to be done by a _________ pump, as it can be made of a variety of materials including plastics.
Piston
Gear
Positive displacement
Sump
Correct answer: (B) Gear
412.Purpose of air lift pump is to
Compress air
Lift compressed air
Lift water from a well by using compressed air
Lift air under negative pressure
Correct answer: (C) Lift water from a well by using compressed air
413.Purpose of hydraulic accumulator is to
Ensure intermittent supply of hydraulic pressure
Increase the pressure and store/ accumulate it
Accumulate pressure to increase force
Generate high pressure to operate hydraulic machines like cranes, lifts, presses etc
Correct answer: (D) Generate high pressure to operate hydraulic machines like cranes, lifts, presses etc
414.Purpose of relief valve in a reciprocating pump is to
Protect the pump against developing excessive pressure
Facilitate unidirectional flow of liquid
Reduce the discharge pressure
Control the rate of discharge
Correct answer: (A) Protect the pump against developing excessive pressure
415.Quicksand is an example of a _________ fluid.
Bingham plastic
Dilatant
Newtonian
Pseudo plastic
Correct answer: (B) Dilatant
416.Ratio of inertial forces to surface tension forces is called the _________ number.
Euler
Froude
Mach
Weber
Correct answer: (D) Weber
417.Ratio of pressure and inertia force gives _________ number.
Weber
Mach
Euler
Froude
Correct answer: (C) Euler
418.Reciprocating pumps are not able to compete with the centrifugal pump for industrial use, mainly because these pumps have
Very low speeds
Smaller discharge
Higher capital & maintenance cost
High vibrations
Correct answer: (C) Higher capital & maintenance cost
419.Reciprocating pumps compared to centrifugal pumps
Deliver liquid at uniform pressure
Can handle slurries more efficiently
Are not subject to air binding
Can be operated with delivery valve closed
Correct answer: (C) Are not subject to air binding