Maximum weight on bit

Input(s)

$\mathrm{L}_{\mathrm{d}}$: Length of Drill Collar $(\mathrm{ft})$

$\mathrm{W}_{\mathrm{d}}$: Unit Wight of Collar $(\mathrm{lbf} / \mathrm{ft})$

SF: Safety Factor (dimensionless)

BF: Buoyancy Factor (dimensionless)

$\alpha$: Wellbore Inclination (degree)

Output(s)

WOB: Maximum Weight on Bit (lbf)

Formula(s)

$$ \mathrm{WOB}=\frac{\mathrm{L}_{\mathrm{d}} * \mathrm{~W}_{\mathrm{d}} * \mathrm{BF} * \cos (\alpha)}{\mathrm{SF}} $$

Reference(s)

Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015. Houston, Texas, Page: 380.