Hazen-William’s Formula

Hazen-William’s Formula

IP system :

For designing water supply pipeline, which are flowing full under hydraulic pressure.

Where P = the pressure loss in psi per foot of pipe.

Q = flow in gpm (1 gallon= 1 USgallon =3.785 litres).

C = coefficient depending upon roughness of pipe (80 to 140).

d = diameter in inches

SI system :

Pm= pressure loss in bars per meter of  pipe.

Qm = flow in litres/min.

d= diameter in mm.

C = coefficient depending upon roughness of pipe (typically 80 to 140)