A. Generally a needle valve
B. Used to release any gases that might be vapour locking the pump
C. Helpful in easy removal of samples
D. All A., B. and C.
Related Mcqs:
- A 2″ gate valve fitted in a pipe is replaced by a similar globe valve. Pressure drop in gate valve was Δp. For the same discharge, the pressure drop across globe valve is__________________?
A. Δp
B. < Δp
C. > Δp
D. Δp2 - For the same terminal conditions and valve size, the pressure drop in a fully opened globe valve as compared to that in a gate valve is___________________?
A. More
B. Less
C. Equal
D. Either A. or B.; depends on the viscosity of the fluid - Foot valve provided in the pump is a ______________ valve?
A. Direction control
B. Back pressure
C. Relief
D. Pressure reduction - A centrifugal pump is used to pump water through a horizontal distance of 150 m, and then raised to an overhead tank 10 m above. The pipe is smooth with an I.D of 50 mm. What head (m of water) must the pump generate at its exit E. to deliver water at a flow rate of 0.001 m3/s? The Fanning friction factor, f is 0.0062 ?
A. 10 m
B. 11 m
C. 11.8 m
D. 30 m - A centrifugal pump used to pump water is used to pump an oil with specific gravity of 0.8 at the same rate. The power consumption will now_________________?
A. Increase
B. Decrease
C. Remain same
D. Data insufficient to predict - A centrifugal pump designed to pump water is employed to pump a more viscous oil. In the later case, the pump_________________?
A. Develops a lower head
B. Capacity is reduced
C. Requires more power
D. All A., B. and C. - Check valve provided in the discharge line of a centrifugal pump serves the purpose of controlling the_______________?
A. Back flow of fluid in the event of stoppage of pump
B. Discharge pressure
C. Flow of liquid during operation of the pump
D. All A., B. and C. - Which is the correct relationship for a centrifugal pump? (Where, D = Impeller diameter, inches H = Head developed, ft of liquid pumped N = Speed of pump, rpm) ?
A. D = 1840 H0.5/N
B. D = 1840 N/H0.5
C. H = 1840 D0.5/N
D. D = 1840 H/N - Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the _______________ decreases?
A. NPSH required
B. BHP required by the pump
C. Head of the liquid pumped
D. All A., B. and C. - While starting a centrifugal pump, its delivery valve should be kept___________________?
A. Opened
B. Closed
C. Either opened or closed; it does not make any difference
D. Either opened or closed; depending on the fluid viscosity
