套管开窗侧钻技术在贵州地热钻井中的应用

Application of Sidetracking in Casing in Guizhou Geothermal Drilling

摘要:

普安县江西坡地热井在钻进到井深907.91 m时遇到了卡钻事故，解卡失败后，进行倒扣处理，剩余75.53 m“落鱼”无法取出，“鱼头”位置井深832.38 m。为绕开“鱼头”位置继续钻进，必须进行开窗侧钻。在已经下套管固井的情况下，选用了DXQ210/H型导斜器作为导斜工具，使用KCXZ216型铣锥作为磨铣开窗工具，进行了套管内侧钻开窗作业。在分析事故概况的基础上，介绍了导斜器的工作原理和套管内开窗侧钻的技术方案，总结了施工作业中的注意事项，最终侧钻成功并顺利钻进到2364.56 m完钻。

关键词:地热钻井;套管开窗;导斜器;铣锥;侧钻

Abstract:

Sticking accident happened at the drilling depth of 907.91m in Jiangxipo geothermal well, back-off was used after releasing failed, the remainded 75.53m drilling tool could not be taken out and the top end of the drilling tool was at the depth of 832.38m. It is necessary to adopt sidetracking to bypass the top end of the drilling tool for continue drilling. In the case of casing cementing completion, sidetracking window from inside casing was carried out with DXQ210/H type deflecting device selected as the deflecting tool and KCXZ216 type taper miller as milling tool. Based on the analysis on the general situation of the accident, the paper introduces the working principle of the deflecting device and the technical scheme of sidetracking window from inside the case and summarizes the attentions in the construction operation. The sidetracking is smoothly completed at the depth of 2364.56m.

Key words:Geothermal drilling; casing window; deflecting device; milling cone; side drill