Pressure required to overcome gel strength of mud inside the drill string

Input(s)

y: Gel Strength of Drilling Fluid $\left(\mathrm{lb} / 100 \mathrm{ft}^{2}\right)$

d: Inside Diameter of Drill Pipe (in.)

L: Length of Drill String ( $\mathrm{ft}$ )

Output(s)

$\mathrm{P}_{\mathrm{m}}$: Pressure Required (psi)

Formula(s)

$$ \mathrm{P}_{\mathrm{m}}=\frac{\mathrm{y} * \mathrm{~L}}{300 * \mathrm{~d}} $$

Reference(s)

Lapeyrouse, N. J., 2002, Formulas and Calculations for Drilling, Production and Workover, Second Edition, Gulf Professional Publishing, Page: 79.