- 1). Determine the atmospheric pressure in feet of head. Assume the system is at sea level which would give an atmospheric pressure of 33.96 feet.
- 2). Determine the vapor pressure of the liquid to be pumped. Assume the system will pump water. Water at atmospheric conditions and 75 degrees Fahrenheit has a vapor pressure of 1.02 feet. Assume the water has a height above the pump of 10 feet and there is 1/2 feet of frictional losses in the suction line.
- 3). Calculate the NPSHA using a calculator. The formula is 33.96 feet - 1.02 feet + 10 feet - 0.5 feet for a NPSHA of 42.44 feet or 18.37 psi.
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