Pumps running in series

Finally, we consider an arrangement of pumps running in combination 

The same previously mentioned critical tips apply, plus one more. Upon observing the system curve, with the pump curves, it appears that the operator can operate any one pump, or any two, or any three or four pumps. Actually there is no option to run three pumps in this 

Along with the sounds, evidence and signs of cavitation, there is a broad range of other information and signals available to the maintenance mechanic. Almost all mechanics have seen the gouge and scratch marks, and signs of heat on the pump when disassembled in the shop. Sadly, most mechanics are never trained to interpret these marks. 

Let s begin with a discussion and explanation on how a volute centrifiigal pump works. 

See Table opposite for what is happening inside the pump around the internal volute wall. 

---

Let s begin by viewing an arrangement of pumps running in series, followed by the development of the series curve (Figure 8-28). 

---