The stator section of a centrifugal pump, after flow exits the impeller, is usually either a ‘diffuser’ or a ‘volute’. The purpose of each of these two stator types is to efficiently diffuse velocity energy into pressure. Diffusers are characterized by a plurality of radially symmetric diffusing passageways surrounding the impeller. Either a volute-shaped or […]
Pump Handbook Fourth Edition – A Book Review
Years ago I owned a copy of Pump Handbook 1st Edition, by Karassik, Krutzsch, Fraser, and Messina. While it was a book to have on the shelf, it was not my primary source of pump engineering reference material. I obtained most of my pump technical information from other books and publications. Eventually someone “borrowed” my […]
Specific Speed – Does it Matter?
To the pump engineer or pump manufacturer specific speed is terrifically important. To the specifying engineer or user – maybe, maybe not. The term specific speed comes up frequently in pump literature, in technical papers and is always covered in pump text books. It is frequently heard in pump technical banter and if one doesn’t […]
Is there any confusion about NPSH?
Net Positive Suction Head (NPSH) is perhaps the most misunderstood concept in pumping technology. The main source of confusion stems from multiple uses of the term in different but related contexts. One usage of the term NPSH is to denote the suction performance characteristic of the pump itself, independent of the system into which it […]