南71井大斜度定向钻井液技术

Drilling Fluid Technology in Highly-deviated Directional Well Nan71

南７１井是河南油田的一口大位移、大斜度、长裸眼、双靶心定向井，完钻井深２０２４ｍ，井斜 ５５°，位移８８３ｍ。针对该地区地层胶结性差、造浆性强的特点，优选了聚合物混油钻井液体系并制定了相应的工艺技术措施。实践表明，该体系抑制能力、防塌能力、携砂能力强，润滑性能好，满足了大斜度钻井的施工需要。

Well Nan 71, the first extended reach, highly-deviated, long open hole and dual bull's-eye well in Henan oilfield, has a drilled depth of 2024m borehole deviation 55°and displacement 883m. In viewing of the poor cementation and strong mud yield of the formations in this area a polymer drilling fluid with oil mixed is selected and the relevant technological measures are optimized. Field application show that this drilling fluid system has strong inhibitive, anti-caving and prop-carrying capabilities and good lubricity and can meet the requirements of highly-deviated well drilling.