细观损伤力学在气体钻井井壁稳定性研究中的应用  

Wellbore Stability in Gas Drilling by Meso-damage Mechanics

作　　者：周翔宇[1] 邹灵战 邓金根[1] 郑立会[1] 

机构地区：[1]中国石油大学,北京102249 [2]中国石油集团钻井工程技术研究院,北京100085

出　　处：《重庆科技学院学报（自然科学版）》2010年第6期65-69,共5页Journal of Chongqing University of Science and Technology：Natural Sciences Edition

基　　金：长江学者和创新团队发展计划项目(IRT0411);全国百篇优秀博士论文基金项目(200349)

摘　　要：用RFPA2D软件建立气体钻井井眼稳定的损伤力学模型,通过跟踪声发射信号研究井壁围岩在应力下的损伤演化,从细观损伤力学的角度探讨气体钻井时井壁围岩的损伤演化,以及转换介质后井壁失稳的原因。研究发现,气体钻井时井眼周围一定范围内出现损伤区,损伤区内形成微裂纹和裂缝,转换介质后由于泥浆渗入、压力波动而导致损伤区坍塌。The study of borehole stability is the key technique to solve the puzzle of gas drilling adaptability. It has significance to promote the application of gas drilling,to run-up the ROP of drill and to accelerate the progress of oil and gas exploitation and exploration. Numerical model of borehole in gas drilling is set up by using RFPA2D,and damage evolution around borehole is studied by tracking acoustic emissions. The study indicates that there exists a damage zone around borehole in gas drilling. In excavation-damaged zone （EDZ）,microcracks arise,propagate and coalesce into macro fracture,which easily results in collapse of damage zone after transforming medium because liquid phase seeps into EDZ and pressure fluctuation of liquid column. The research result shall be applied in transforming medium to keep wellbore stable in gas drilling. The economical and engineering value is great along with wide application of gas drilling.

关 键 词：气体钻井 井壁稳定 损伤力学 

分 类 号：TE249[石油与天然气工程—油气井工程]