2 replies to this topic

[Itineris]

When looking at a standard centrifugal pump curve of head vs flow is the total dynamic head of the liquid at the pump discharge equal to the head of the pump plus the head of the liquid at the pumps suction?

 

I am a little curious about how pump suction pressure influences the performance of a centrifugal pump. I realize you  have to supply the necessary net positive suction head, but what about entering a pump at too high of a pressure? PD pumps can slip.. does a centrifugal pump fail to boost pressure or become inefficient at a certain high pressure?

 

Thank you for your time.

[fallah]

Hi,

 

Yes, the pump discharge head is pump head plus the pump suction head...

 

When you are preparing the centrifugal pump data sheet, you should specify the maximum suction pressure based on which pump's shut off pressure to be specified by vendor; as the pump's shut off pressure would be equal to pump's differential pressure plus suction pressure. Then for a given flowrate, the pump will boost any high suction pressure below prespecified maximum suction pressure by adding the corresponding differential pressure without any problem, as long as the allowable working pressure of the pump and design pressure of the pump suction /discharge lines can tolerate that hign suction pressure and subsequent pump's shut off pressure...

[Itineris]

Fallah,

 

Thank you for the pump guidance.