What is priming of a centrifugal pump and why it is required

What is priming of a centrifugal pump and why it is required - Power Plant Guruji

What is Priming?

The removal of air by filling the pump passages i.e, flow passages.

eg. The impeller and the volute casing with liquid.

Priming is the adding of water to the pump cavity so that enough suction can be created by the impeller to pull water.

Priming in centrifugal pump

Why is Priming essential in a Centrifugal Pump?

Centrifugal pump does not displace liquid positively.
They cannot displace gases and Vapours.
Removalof these gases, air bubbles and vapours is very essential and a must before starting any centrifugal Pump in order to extend the pump life.

What are different methods of priming ?

PRIMING METHODS

With a flooded suction
A bypass around the discharge check valve
The foot valve with auxiliary liquid supply
An ejector for priming
A priming tank holding the supply of liquid
Vacuum pumps (manually/automatically) controlled to prime the main pump

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