What is the maximum theoretical suction lift (metres) of a reciprocating pump ?

Related Mcqs:

1. Maximum theoretical suction lift for water at 15°C by a centrifugal pump is 34 ft. The same for water at 90°C will be _____________________ ft?

   A. 40
   B. 34
   C. 8
   D. 37

2. Actual lift of a pump is always less than the theoretical lift and is limited by the__________________________?

   A. Specific gravity & temperature of the liquid
   B. Leakage & pressure decreasing at higher elevations
   C. Frictional resistance through pipes, fittings & passages
   D. All A., B. and C.

3. In centrifugal pump operation, the cavitation can be eliminated by maintaining suction pressure ______________ the vapor pressure of the liquid at the suction temperature?

   A. Lower than
   B. Higher than
   C. Equal to
   D. None of these

4. The percentage slip in a reciprocating pump set is given by the % of (where, Q1 = actual discharge Q2 = theoretical discharge) ?

   A. Q1/Q2
   B. Q2/Q1
   C. (Q2 – Q1)/Q1
   D. (Q2 – Q1)/Q2

5. A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, then the new head will be ______________ metres?

   A. 2
   B. 4
   C. 8
   D. 5.5

6. A double acting reciprocating pump compared to a single acting pump (of almost same size working under same pressure levels) would give almost double___________________?

   A. Head
   B. Discharge
   C. Efficiency
   D. None of these

7. 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

8. 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

9. 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.

10. Net positive suction head (NPSH) of a centrifugal pump must be____________________?

    A. Greater than the vapour pressure of the liquid
    B. Less than the vapour pressure of the liquid
    C. Equal to the vapour pressure of the liquid
    D. Less than barometric pressure