BHP corrections in beam-pumped wells. 1. Bottom hole pressure methods and corrections are reviewed. [Bottom hole pressure]

Bottom hole-pressure (BHP) measurements taken from pumping wells require correction to account for gravity variations in the well's column of fluids. Although the two basic BHP-measurement methods - pressure-bomb and acoustic - are both relatively inexpensive and easy to use, neither can be applied directly to wells that produce casing head gas because the contribution of the gas liquid's hydrostatic pressure to the BHP is difficult to estimate. Several variations of these methods that attempt to overcome such problems include the Walker's, the gas-blowaround, and the gradient-correction-factor methods; two, published correlations can be used to calculate the pressure gradient in static annular gas-liquid columns.