Pressure required to break circulation - Annulus
Input(s)
y: Gel strength of drilling fluid \(\left(\mathrm{lb} / 100 \mathrm{ft}^{2}\right)\)
\(\mathrm{L}\): Length of Drill String \((\mathrm{ft})\)
Dh: Diameter of hole (in.)
Dp: Diameter of drill pipe (in.)
Output(s)
\(P_{g s}\): Pressure to overcome mud's gel strength inside annulus (psi)
Formula(s)
\[
P_{g s}=\frac{y}{300 *(D h-D p)} * L
\]
Reference(s)
Formulas and Calculations for Drilling, Production and Workover, Second Edition, Lapeyrouse, Page: 79.