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NFPA 13 §28

Hazen-Williams pipe sizing (friction loss)

Friction loss per metre of pipe using the Hazen-Williams equation (metric form).

Δp/L = 6.05·10^5 · Q^1.85 / (C^1.85 · d^4.87) where Q in L/min, d in mm, Δp in bar/m.

Result
Friction loss per metre
0.0118 bar/m
Total friction loss
0.589 bar
Equivalent head
6.01 m

Formula: Δp/L = 6.05e5 · Q^1.85 / (C^1.85 · d^4.87)

Reference: NFPA 13 §28

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