METHOD FOR DETERMINATION OF LEAKAGE AMOUNT THROUGH LEAKY LIFT STRING OF SUCKER-ROD PUMPING UNIT Russian patent published in 1994 - IPC

FIELD: oil production with use of sucker-rod pumping units, both, in vertical and inclined and directional wells. SUBSTANCE: method consists in increasing pressure at wellhead by closing flow line valve with operating pumping unit. Pumping unit is stopped with upper position of horsehead and wellhead pressure drop curve is registered. Wellhead pressure is raised again up to initial pressure and pumping unit is stopped with horsehead in lower position and second curve of pressure drop is registered. Value of fluid leakage through leaky lift string when pump plunger pair is leaky is determined by formula. Should no leakage be detected through plunger pair, leakage through leaky lift string is determined qualitatively by the intensity of pressure drop for time period. EFFECT: higher efficiency. 1 dwg