抽油井示功图诊断分析方法研究

Diagnosis of Dynamometer Card of Pumping Well

抽油井示功图是掌握深井泵工作状况和油井流入动态的重要手段,不同形状的示功图代表了不同的工况。针对油田现场普遍存在的表示井下供液不足的刀柄形示功图,提出通过在示功图上确定十个特征点将示功图分为八段,结合采油原理定性分析示功图形状特征,进而提出定量计算井下干摩擦力、井液密度和泵阀阻力等井况参数的方法。现场应用证明了所提方法的有效性。

The dynamometer card(DC)is an essential method of monitoring the working conditions of sucker-rod pumping and the inflow performance relationship of pumping well.The various shapes of the DC indicate the different working conditions of pumping well.In view of the hilt shaped DC commonly existing in oil field, which indicates that the downhole fluid supply is insufficient, it is proposed that the DC can be divided into eight sections by determining ten characteristic points on the DC,and the shape characteristics of the DC can be qualitatively analyzed by combining with the principle of oil production technology.Furthermore, the method of quantitative calculation of well condition parameters such as downhole dry friction, well fluid density and pump valve resistance etc.is proposed.Field application shows the effectiveness of the proposed method.