老井侧钻之悬挂器回接失败原因分析

Failure analysis for hanger back connection in old well sidetracking

苏里格气田老井侧钻水平井裸眼封隔器完井试验过程中悬挂器回接失败。通过分析老套管侧钻的复杂井况和悬挂器回接结构原理,认为悬挂器回接失败的原因主要是,老套管腐蚀和套管侧钻偏磨造成悬挂器坐封的居中性较差,回插管与回接筒引导结构不合理,导致回插管不能成功插进回接筒等。通过修整回接筒喇叭口,改进回插管的引导结构,优化完井方案,进行施工作业,二次回接取得成功。后续2口试验井的完井作业实现顺利回接,达到了预期改进效果,为老井侧钻裸眼封隔器完井技术的推广应用积累了实践经验。

It failed to connect the hanger again in the process of borehole packer completion testing for the old well sidetracking horizontal well in Sulige gas field.This paper analyzed the cause to ensure the reliable return connection of the hanger.It is considered that the old casing corrosion and the casing sidetrack eccentric abrasion cause the suspension of the hanger to be poorly centered by analyzing the complex well conditions of the old casing sidetrack and the principle of the hanger return structure.It is the main reason that the return cannula cannot be successfully inserted into the return tube.The second return connection is successful for this well by trimming the back tube flare,improving the guiding structure of the back cannula,optimizing the completion plan.The completion operation of the subsequent two test wells was successfully returned,and the expected improvement effect was achieved.This paper accumulated practical experience for the promotion and application of the old borehole side-hole open hole packer completion technology.