FLUID LOAD LINE CALCULATION, CONCAVITY TEST, AND ITERATIONS ON DAMPING FACTOR FOR DOWNHOLE PUMP CARD

摘要

A pump apparatus has a downhole pump disposed in a wellbore and has a motor at the surface, and a rod string operatively moved by the motor reciprocates the downhole pump in the wellbore. A downhole card indicative of load and position of the downhole pump is generated using surface measurements and a wave equation model having an upstroke damping factor and a downstroke damping factor. Actual fluid load lines are determined from the downhole card for upstrokes and downstrokes of the downhole pump, and calculated fluid load lines for from the strokes are determined from load values distributed on the downhole card.