A pump transfers water from one reservoir to another through two cast-iron pipes in series. The first is \(3000 \mathrm{ft}\) of 9-in.-diameter pipe and the second is \(1000 \mathrm{ft}\) of 6-in.-diameter pipe. A constant flow rate of \(75 \mathrm{gpm}\) is tapped off at the junction between the two pipes. Obtain and plot the system head versus flow rate curve. Find the delivery if the system is supplied by the pump of Example 10.6 operating at \(1750 \mathrm{rpm}\).

Data From Example 10.6

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Example 10.6 SCALING PUMP PERFORMANCE CURVES When operated at N = 1170 rpm, a centrifugal pump, with impeller diameter D = 8 in., has shutoff head Ho = 25.0 ft of water. At the same operating speed, best efficiency occurs at Q=300 gpm, where the head is H = 21.9 ft of water. Fit these data at 1170 rpm with a parabola. Scale the results to a new operating speed of 1750 rpm. Plot and compare the results.