Formula 2.50
Depth of a washout - Method 2
Input(s)
$\mathrm{N}_{\mathrm{s}}$: Number of Strokes Required (unitless)
$\mathrm{P}_{\mathrm{o}}$: Pump Output per Stroke (bbl/stroke)
$\mathrm{C}_{\mathrm{p}}$: Drillpipe Capacity $(\mathrm{bbl} / \mathrm{ft})$
$\mathrm{C}_{\mathrm{a}}$: Annular Capacity (bbl/ft)
Output(s)
$D_{w}$: Depth of Washout ( $f t$ )
Formula(s)
$$ \mathrm{D}_{\mathrm{w}}=\mathrm{N}_{\mathrm{s}} * \frac{\mathrm{P}_{\mathrm{o}}}{\mathrm{C}_{\mathrm{p}}+\mathrm{C}_{\mathrm{a}}} $$
Reference(s)
Lapeyrouse, N. J., 2002, Formulas and Calculations for Drilling, Production and Workover, Second Edition Gulf Professional, Publishing, Page: 70.