欠平衡钻井随钻试井数学模型及实用方法研究

认为欠平衡钻井的物理过程与传统的测试理论的主要区别是 :随着欠平衡钻井的进行 ,井深不断增加 ,产层的暴露厚度是时间的函数 ;产能与井底压力是随时间变化的 .在原有的试井理论基础上 ,推导出欠平衡钻井随钻试井数学模型 ,并结合现有的试井方法 ,提出欠平衡钻井随钻试井实用方法——修正压降试井法和修正压力恢复试井法 .同时 ,结合两口井的欠平衡钻井现场实例数据进行了该方法的计算 ,结果与实际地层压力对比 ,偏差较小 ,从而验证了这方法的可行性

Studies on Mathematical Model and Practical Method of Well Testing While Underbalance Drilling (UBD)

Precisely knowing reservoir pressure and flowing behavior and controlling the underbalanced condition at bottom hole is very important to realizing UBD, ensuring safety construction and reaching to predicted productivity target. The main distinction between well testing while UBD and traditional well testing methods is that the exposure thickness of producing formation increases with the increase of well depth. Based on the original well testing theory, the theory of well testing while UBD and the corresponding practical well testing method are derived. The well testing method is applied to two wells. The results of the formation pressure computed by the method are compared with field data, and there is little difference between them. It is shown that the method is reliable.