Design & Sizing第 28 / 110 题
A meter and service must supply 44 gpm. The static supply is 68 psi, elevation loss is 20 psi, the meter loss is 8 psi, and the most remote fixture needs 15 psi. How much pressure remains for pipe friction?
a.18 psi
b.33 psi
c.43 psi
d.25 psi
解析
Available for friction = static - elevation - meter - fixture requirement = 68 - 20 - 8 - 15 = 25 psi. This leftover is spread over the developed length to set the allowable friction rate per 100 ft. If friction loss at the chosen pipe size exceeds 25 psi, the pipe must be enlarged.
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