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Equivalent Circulating Density

Effective mud density while circulating, including friction pressure.

Formula

ECD = MW + \frac{\Delta P}{0.052 \times TVD}

Variables

ECDCirculating density (ppg)

MWStatic mud weight (ppg)

\Delta PAnnular pressure loss (psi)

TVDDepth (ft)

Example

MW=10, ΔP=300, TVD=10000: ECD = 10.58 ppg

Did You Know?

Keeping ECD within the narrow window between pore and fracture pressure is critical to well control.

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