It’s not unusual for folks to wax and wane during conversations about experiences that we have had or read about that push the limits of our experience. When I worked as a pump applications engineer, I used to pour over the catalogs and pump curves of all the various manufacturers and think about what each type of pump was capable of. One of the pumps that captured my imagination were the large axial flow pumps that could move hundreds of thousands of gallons per minute at low head pressure. These were the types of pumps that could pump water out of a whole city if something went awry. I prepared myself for the day that someone might call and need help specifying one of these marvels of engineering.
There were a few phone calls that came up over the years that warranted the movement of large quantities of water at low head; contractor dewatering for tunnel projects and emptying out a drydock to name a couple. Our service department worked on some pumps used for flood control where the volute was so big you could stand up in it. At the other end of the spectrum are pump applications that require both high flow and high head. An image that comes to my mind from younger days is seeing the harbor fireboats in full fountain plume.