Duplex pump factor

Input(s)

$\mathrm{D}_{\mathrm{L}}$ : Piston Diameter (in.)

$\mathrm{D}_{\mathrm{r}}$ : Rod Diameter (in.)

$\mathrm{L}_{\mathrm{S}}$ : Stroke Length (in.)

$\mathrm{PF}_{\mathrm{d}}$ : Duplex Pump Factor (bbl/stroke)

\mathrm{PF}_{\mathrm{d}}=\frac{3.1415 * \mathrm{~L}_{\mathrm{S}} *\left(\left(2 * \mathrm{D}_{\mathrm{L}}^{2}\right)-\mathrm{D}_{\mathrm{r}}^{2}\right)}{2 * 9702}

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