Parallel and Series Operations

Discflo pumps can be operated in series and in parallel to meet a wide range of applications. For these multiple pump operations, a system head curve for the entire capacity must be produced and the individual head-capacity curves for each pump superimposed on it.

For parallel operation of two or more pumps, you need to add horizontally the capacities of the same heads to obtain the combined performance curve. For series operation, you need to add vertically the heads at the same to obtain the combined performance curve.

Since the Discflo pump operates at the intersection of its head-capacity curve and the system curve, superimposing the system curve on the pump performance curve indicates the expected flow and at what heads each pump will operate. Fig 1.8 illustrates a two pump series and two pump parallel operation. It shows a typical head-capacity curve for a single pump designed for 1000 GPM (227 m3/h) flow rate at 60-ft (36m) head.

From the equations given earlier, it follows that:

Two pumps in series will deliver 1000 GPM (227 m3/h) at 120-ft (36m) head.
Two pumps in parallel will deliver 2000 GPM (454 m3/h) at 60-ft (18m) head.

In this example, the system curves are drawn on the assumption that there is 20-ft of static head.