Side force at bit in anisotropic formation
Input(s)
p: Buoyed Weight of Drill Collar (ppf)
E: Modulus of Elasticity (psi)
I: Moment of inertia of Drill Collar (in. \({ }^{4}\) )
r: Radial Clearance Between Hole and Collar (ft)
\(\theta\): inclination Angle (degree)
W: Weight on Bit (lbf)
Output(s)
F: Side Force on Bit (lbf)
Formula(s)
\[
\mathrm{F}=\mathrm{p} *\left((\mathrm{E} * \mathrm{I})^{0.5}\right) *\left(\left(\frac{\mathrm{W}}{24}\right) *\left(\left(\frac{24 * \mathrm{r}}{\mathrm{E} * \mathrm{I} * \mathrm{p} * \sin (\theta)}\right)^{0.75}\right)-\left(\left(\frac{1.5 * \mathrm{r}}{\mathrm{E} * \mathrm{I} * \mathrm{p} * \sin (\theta)}\right)^{0.25}\right)\right)
\]
Reference(s)
Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015. Houston, Texas, Page: 378.