气体钻水平井井壁稳定性分析新方法

New Method of Hole Stability Evaluation of Horizontal Air Drilling

与常规钻井液钻井相比,气体钻井技术在提高机械钻速、保护油气层等方面有着无可比拟的优势,其中井壁稳定是气体钻井过程中最为突出的问题。目前对于气体钻水平井没有一套合理的井壁稳定分析方法,给现场钻井带来很多困难。在直井井壁稳定分析理论模型的基础上,通过应力转换,确定水平井段围岩应力,结合测井数据去水化校正,建立气体钻水平井井壁稳定计算模型,形成了一套完整的气体钻水平井壁稳定分析方法。将该方法应用于川西地区气体钻水平井井壁稳定分析,理论分析与工程实际结果吻合,验证了该方法的可行性。

Compared with conventional mud drilling,air drilling technology has incomparable advantages in advancing of ROP and reservoir protection,among which borehole stability is the prominent issue of air drilling.At present there is no one fitting borehole stability evaluation for air drilling horizontal well,which causes problems for site drilling.On the basis of theoretical model of vertical well stability analysis,this paper has established rock stress of horizontal section and founded calculation model of air drilling horizontal well stability with the combination of log data hydration correction,finally formed a integrated set of evaluation method for air drilling horizontal well stability.This method is applied to air drilling horizontal well in western Sichuan and the theory accords well with the field practice,which proves the feasibility of this method.