焦页197-4HF页岩气长水平段井钻井关键技术

Key technologies of drilling for long horizontal interval shale-gas well,Jiaoye 197-4HF

焦页197-4HF井为焦石坝二期页岩气开发的一口长水平段水平井,钻遇地层地质条件复杂。受构造变化大、断层发育、页岩储层埋藏深、地层压力体系认识不清、垂深预测误差大等因素影响,钻井施工难度大。针对定向施工摩阻扭矩大、井漏频繁、地层可钻性差、钻头磨损严重等难点,采取优化井身结构及井身剖面、优选钻头、精细控制井身轨迹、优选钻井液体系、优化堵漏措施等技术,顺利完成该井施工任务。针对页岩气长水平段钻井的提速提效,提出了加强针对龙潭组和茅口组地层的PDC钻头个性化设计、钻井各阶段使用相应工具、开展平桥页岩气井堵漏工艺及油基钻井液封堵技术的研究等建议。

Jiaoye 197 -4HF well is a horizontal one with long horizontal interval in shale -gas development of the second phase in Jiaoshiba area. Compared with the first phase, the geological condition is more complicated. Influenced by the factors such as big structural change, developed faults, deep buried shale reservoir, unclear consideration of formation pressure system, and big error of TVD prediction, the drilling construction is very difficult. In order to solve the problems such as large friction and torque in the drilling construction, frequent lost circulation, poor drillability of formation , serious wear of bit, etc. , it was carried out optimizations of bore frame, well profile and bit, wellbore trajectory controlled precisely, leaking plugging, and drilling fluid system. Finally, the well was drilling successfully, creating a record of the longest horizontal displacement in Nanchuan block. And also some suggestions were put forward to improve the speed and efficiency of horizontal well with long horizontal interval in shale - gas development.