Borehole torsion - Cylindrical helical method

Input(s)

$\mathrm{k}_{\mathrm{h}}$: Horizontal Curvature (degree/100ft)

$\mathrm{k}_{\mathrm{v}}$: Vertical Curvature (degree/100ft)

$\mathrm{k}$: Curvature of Wellbore Trajectory (degree/100ft)

a: Inclination Angle (degree)

Output(s)

t: Borehole Torsion-Cylindrical Helical Method (degree/100ft)

Formula(s)

$$ \mathrm{t}=\mathrm{k}_{\mathrm{h}} *\left(1+\left(2 * \frac{\left(\mathrm{k}_{\mathrm{v}}\right)^{2}}{\mathrm{k}^{2}}\right)\right) * \sin (\mathrm{a}) * \cos (\mathrm{a}) $$

Reference(s)

Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015. Houston, Texas, Page: 84.