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Pipe Flow & Headloss

Blue fields contain editable defaults. Replace them with project-specific values when available.

Calculated results

Results

Velocity— ft/sec
Headloss— ft/1,000 ft
Pressure loss— psi/1,000 ft
Formulas and variable definitions

v = (Q ÷ 448.831) ÷ [π(D/12)²/4]

hf = 4.52LQ1.85 ÷ (C1.85D4.87)

ΔP = hf ÷ 2.30666

Variables: v = velocity (ft/sec); Q = flow (gpm); D = inside diameter (in); C = Hazen-Williams coefficient; L = 1,000 ft; hf = headloss (ft); ΔP = pressure loss (psi).

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