METHOD OF DIAGNOSING SUCKER ROD PUMPING PLANTS (VERSIONS) Russian patent published in 2003 - IPC

FIELD: oil producing industry. SUBSTANCE: invention relates to methods of checking operation of pumping plants by measuring electric parameters of motors. It can be used for diagnosing condition of submerged sucker-rod pumping plants. According to proposed method average active power output of pumping plant is measured at discrete time intervals, speed of change of output power within said time intervals measured, phase curve is plotted, diagnostic coefficients proportional to value of consumed power for each quarter of phase plane are calculated separately and, basing on conditions showing ratio of Euclid an distances from center of coordinates of phase plane to each point of phase curve, conclusion is made on condition of pumping plant depending of counterbalancing of pumping plant. For this purpose, first a₁ and second a₂ harmonics of law of changing of average active power are discriminated and condition of counterbalancing of pumping unit is found basing on relationship between a₁ and a₂. First and second harmonics of active power are calculated during operation of pumping unit using number of readings N in each quarter of phase plane or by finding summary number of readings providing mean value of speed of changing of average active power equal to zero. Invention provides trustworthiness of results of diagnosing condition of sucker-rod pumping units owing to preliminary finding of counterbalancing of pumping unit by accurately determining accurate number of readings in period of pumping. EFFECT: improved reliability of diagnosing condition of sucker rod pumping plants. 3 cl, 3 tbl, 11 dwg