4.29 Two Bell & Gossett Series 80-SC 2 × 2 × 7 pumps operating at 1750 rpm are connected in parallel. A third pump, a Bell & Gossett Series 80-SC 2 × 2 × 7 pump operating at 3500 rpm is connected in series with the parallel pumps as shown in Figure P4.29.

This composite pump combination is connected to a pipe network with the following system curve:
= [ ]+

 

 
H 10 ft 0.0115 V
ft gpm p 2 2 Determine the following for this system:

a. The system curve up to 140 gpm

b. The composite pump curve up to 160 gpm

c. The operating point (head and capacity) of the combined pump and pipe system