Priming of a centrifugal pump is done to
A. Increase the mass flow rate of fluid
B. Develop effective pressure rise by the pump
C. Avoid chances of separation inside the impeller
D. None of these
Answer: Option B
Solution (By Examveda Team)
The correct answer is Option B: Develop effective pressure rise by the pump.Here's why:
Priming a centrifugal pump means filling the pump casing and suction pipe completely with the liquid to be pumped *before* starting the pump.
Why is this important?
If the pump casing is filled with air or gas, the impeller (the rotating part) will mostly just churn the air.
Centrifugal pumps need to be filled with liquid to work correctly.
Let's look at the other options:
* Option A: Increase the mass flow rate of fluid: Priming doesn't directly increase the flow rate once the pump is running, but is a prerequisite for pumping to commence.
* Option C: Avoid chances of separation inside the impeller: While cavitation (separation) *can* be worsened by improper priming, the *primary* reason for priming is to create an initial pressure head.
* Option D: None of these: This is incorrect since priming does have a specific purpose.
Therefore, the main reason for priming is to remove air and create a liquid-filled environment so the impeller can effectively develop pressure and begin pumping.
This Question Belongs to Chemical Engineering >> Fluid Mechanics
The correct answer is: B. Develop effective pressure rise by the pump
Explanation:
Priming of a centrifugal pump is the process of filling the pump casing and suction line completely with liquid before starting the pump. This is necessary because:
Centrifugal pumps are not self-priming — they cannot pump air or gases effectively.
Without priming, the pump impeller would rotate in air, and no pressure would be developed.
Proper priming ensures that there is liquid at the impeller eye, allowing the pump to develop the required pressure and initiate flow.
So, the purpose of priming is to develop effective pressure rise by the pump and initiate pumping action.
Therefore, the correct option is:
✅ B. Develop effective pressure rise by the pump.
Why the other options are incorrect:
A. Increase mass flow rate — Mass flow rate is a result of the pump operating correctly, but priming itself doesn’t directly increase it.
C. Avoid chances of separation inside the impeller — Cavitation or flow separation is related more to pressure conditions and vapor pressure, not specifically addressed by priming.
D. None of these — Incorrect, as option B is correct.