FORMULAS
Frequently used formulas in pipeline construction; 1. h = f(LV 2 /2Dg) h : Head loss (m) L : Length of pipeline (m) D: Diameter of pipe (m) (Normally nominal diameter presented in meter is used.) V: Flow velocity (m/s) g : Acceleration of gravity (= 9.8 m/s2) f : Head loss coefficient 2. For water pipeline, Hazen-Williams formula is commonly used. V = 0.35464C H D 0.63 I 0.54 Q = 0.27853C H D 2.63 I 0.54 I = 10.666 C H -1.85 D -4.87 Q 1.85 Where, CH : Coefficient For cement mortar or epoxy lined ductile iron pipe, a CH value of 150 can be used; however for design purpose, 130 is recommended, which includes losses in fittings, valves and other facilities, plus some allowance. I : Hydraulic gradient (unit head loss of the pipeline) = h/L Q : Flow volume (m3/s)