摘要
为有效克服气体钻井过程中出现的井壁失稳现象,提出一种气体钻井井壁稳定性分析的简易方法。该方法在对传统气体钻井井壁稳定性理论的利弊进行分析的基础上,从气体钻井井壁围岩的力学特性出发,确定了井壁围岩应力场的分布,结合Mohr-Coulomb准则,建立了气体钻井条件的井壁稳定模型,即弹塑性模型和硬脆性模型,成功解释了气体钻井条件下地层进入塑性状态变形达到一定程度,井壁坍塌井径扩大后,地层趋于稳定的现象。将该计算模型应用于满东2井的井壁稳定性分析,结果表明:理论分析结果和工程实测数据对比,计算结果较为准确,验证了该模型较为有效。
In order to overcome the borehole unstability in gas drilling,a simple means for gas drilling wellbore stability analysis was proposed.This means analyzed the benefits and drawdowns of the conventional gas drilling wellbore stability theory and determined the stress field distribution of the wellbore surrounding rocks on base of the mechanical features.The gas drilling wellbore stability model which is actually elastoplasticity model and friable hard model was built up as per Mohr-Coulomb Law.And this model can successfully demonstrate the formation stability trends after the plastic deformation of the gas drilled formation goes up to some degree and wellbore collapsed and enlarged.The calculation model was used on the wellbore stability analysis of Mandong-2 Well.In conclusion, according to comparison between theoretical analysis results and measured data,the calculated data is more accurate and the model is proved to be better.
出处
《石油钻采工艺》
CAS
CSCD
北大核心
2009年第6期48-52,共5页
Oil Drilling & Production Technology
基金
国家自然科学基金项目(编号:9051005)资助
关键词
气体钻井
井壁稳定
坍塌压力
gas drilling wellbore stability collapse pressure
