桂中￣南盘江地区黔水地1井钻井关键技术

Key drilling technologies for well Qianshuidi 1 in Guizhong-Nanpanjiang area

郭军 陈相霖 赵训林 王文彬 李岩 韩菲1

湖南省煤炭地质勘查院，湖南 长沙 410000 中国地质调查局油气资源调查中心，北京 100083

The Coal Geological Exploration Institute of Hunan Province, Changsha 410000, China Oil and Gas Survey, China Geological Survey, Beijing 100083, China

黔水地1井是一口页岩气调查井，位于桂中￣南盘江地区，钻遇的石灰岩地层裂缝、溶洞发育，泥页岩地层厚度大、水敏性强、承压能力弱，施工过程中发生了垮孔、恶性漏失、卡钻等井下复杂情况。为此，利用转盘带动跟管进行钻进，解决了因溶洞垮塌所造成的导管段不能成孔的问题；顶漏强行钻进技术实现了一次性成功封隔1 001.34 m深岩溶发育地层，并形成了行之有效的施工措施；主动节流循环避免了因钻井液密度增加过大所引起的井漏；优化的聚磺钻井液体系提高了钻井液的拟制性和流变性，预防了侧钻过程中井漏、垮塌等情况的发生；弹韧性双凝双密度水泥浆体系保证了固井质量。各种技术的创新性运用，不但有效解决了该井的各种技术难题，节省了施工成本，而且形成了一套适宜于该区页岩气钻井的关键技术，为今后该区和相邻区块的类似工程提供了指导和借鉴。

Well qianshuidi 1 is a shale gas survey well located in the Guizhong-Nanpanjiang area. The limestone strata encountered are well developed with cracks and karst caves, and the mud shale has a large thickness, good water sensitivity and weak pressure-bearing capacity. During the drilling process, complex conditions such as borehole collapse, severe mud losses, stuck pipe, and coexistence of kick and losses. Therefore, the rotary table is used to drive the following pipe to drill, which solves the problem that the pipe section cannot form hole caused by the collapse of karst cave. The technique of top leakage forced drilling has successfully sealed off 1,001.34 m karst strata at one time, and formed an effective construction measure. The active throttling circulation avoids the mud loss caused by excessive increase of drilling fluid density. The optimized polysulfonate mud system improves the inhibitory and rheological properties of drilling fluid, and prevents the occurrence of mud loss and borehole collapse during sidetracking. The ductile double-coagulation and double-density cement slurry system ensures the cementing quality. The innovative application of various technologies not only effectively solves various technical challenges of the well and saves construction costs, but also forms a set of key technologies suitable for shale gas drilling in this area, which provides guidance and reference for the similar project of this area and the adjacent blocks.

10.6056/dkyqt202103026