You must determine the specifications for a pump to transport water at $60^{\circ} \mathrm{C}$ from one tank to another at a rate of $200 \mathrm{gpm}$. The pressure in the upstream tank is $1 \mathrm{~atm}$, and the water level in this tank is $2 \mathrm{ft}$ above the level of the pump. The pressure in the downstream tank is $10 \mathrm{psig}$, and the water level in this tank is $32 \mathrm{ft}$ above the pump. The pipeline contains $250 \mathrm{ft}$ of $2 \mathrm{in}$. sch 40 pipe, with 10 standard $90^{\circ}$ flanged elbows and six gate valves.(a) Determine the pump head required for this job.

(b) Assuming your pump has the same characteristics as the one shown in Figure 8.2, what impeller size should be used and what power would be required to drive the pump with this impeller at the specified flow rate?

(c) If the water temperature is raised, the vapor pressure will increase accordingly. Determine the maximum water temperature that can be tolerated before the pump will start to cavitate, assuming that it is installed as close to the upstream tank as possible.

Figure 8.2

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Size 2 3 R & C 1% in. Pedestal 3500 rpm 4' minimum NPSH 400 Impeller dia. 300 200 8% in 8% in 7% in 7% in 6% in. 6% in. I Total head feet 100 50 MISSION VALVE AND PUMP COM Semi-open impeller Dia. 6%-8% in. Eye area 9.8 in. Curve 8 S1 20 ft Max. sphere 1% in. Maximum normal capacity for slurries and abrasive fluids 7ft 30% 10ft. 140% 15 ft 145% 50% 50 50 40HP 15 HP 20 HP 30 HP1 25 HP 25ft, 50% 45% 60 HP 50 HP 400 40% 500 600 700 Capacity-U.S. gallons per minute 100 200 300