Is there any limit to the suction lift of a centrifugal pump? If yes, then what is that limit and why it occurs?

Yes, there is a limit to the suction lift of a centrifugal pump. The maximum theoretical limit is approximately 33.9 feet at sea level. This limit is due to the atmospheric pressure.

Here's why:

1. A centrifugal pump works on the principle of creating a vacuum to draw liquid from a source into the pump and then using centrifugal force to push it out.

2. The vacuum is created by the action of the impeller, which pushes the liquid out of the pump, causing a drop in pressure at the pump inlet. This drop in pressure allows atmospheric pressure to push the liquid from the source into the pump.

3. However, atmospheric pressure can only push the liquid up to a certain height. At sea level, where atmospheric pressure is highest, this height is approximately 33.9 feet.

4. As you go higher in altitude, the atmospheric pressure decreases, and so does the maximum suction lift.

5. Also, this is a theoretical limit. In practice, the limit is often less due to factors such as friction losses in the piping and the vapor pressure of the liquid being pumped.

6. If the suction lift exceeds the limit, the pump will not be able to draw the liquid into it, leading to a condition known as cavitation, which can damage the pump.