Q & A > Question Details
Centrifugal pump (say A) is designed for suction pressure 2.6kgf/cm2 with plan 11. Now if in suction we route some material @10kgf/cm2 with a 1/3 of flow of the said A pump by keeping discharge OPEN, what will happen? Is there any chance of seal leak?
20/03/2010 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
The pump should work O.K. I am visualizing the pump curve. If your flow is less, the pump will be capable of increased head. At higher suction pressure, the pump will be capable of even more head. The higher head needs to be dissipated by either more backpressure from the system or by closing off the discharge valve , manual or control. It is good practice to start a centrifugal pump with the discharge valve closed, and gradually open it until the desired flow is reached. If the system backpressure with the discharge valve wide open happens to give the desired flow, then it's O.K. to run that way without harming the pump. Transfer pumps are often run that way.