Friction loss (psi/100 ft) and velocity for water flow in plastic PVC pipe schedule 40
The diagram below indicates friction loss for water flow through plastic schedule 40 PVC pipe.
The calculation is based on the Hazen-Williams Equation with a Hazen-Williams coefficient c = 140.
Velocities between 7 to 10 feet per second are common. In general velocities above 5 feet per second should be avoided.
- 1 gal (US)/min =6.30888x10-5 m3/s = 0.0227 m3/h = 0.06309 dm3(litre)/s = 2.228x10-3 ft3/s = 0.1337 ft3/min
- 1 ft/s = 0.3048 m/s
- 1 psi (lb/in2) = 6,894.8 Pa (N/m2) = 6.895x10-3 N/mm2 = 6.895x10-2 bar = 27.71 in H2O at 62oF (16.7oC) = 703.1 mm H2O at 62oF (16.7oC) = 2.0416 in mercury at 62oF (16.7oC) = 51.8 mm mercury at 62oF (16.7oC) = 703.6 kg/m2 = 2.307 Ft. H2O