苏53区块工厂化钻井完井关键技术
Key Technologies of Factory Drilling and Completion in Su 53 Block
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摘要: 苏里格气田是国内最大的致密砂岩气田,苏53区块是该气田目前实施水平井整体开发的唯一区块。为提高该区块的开发效率,实现低成本开发,以前期实践和国内外工厂化作业先进经验为基础,通过强化区域地质研究,优化方案设计,加强施工管理,形成了适合苏里格气田工厂化作业的钻井完井技术。该技术主要包括水平井地质导向技术、钻井技术、储层改造技术等。地质导向技术主要通过完善地质模型和调整井眼轨迹,实现水平井准确入靶和高效钻进;钻井技术主要为优化井身结构及井眼轨道,优选PDC钻头和钻井液体系及设计钻机平移系统等;储层改造技术是根据区域地质特征及完钻参数,将体积压裂融入同步压裂,以提高储量动用。苏53区块通过实施工厂化钻井完井技术,水平井平均单井钻井周期比该区块常规水平井缩短15.98 d,平均单井储层钻遇率比该区块常规水平井提高4.9百分点,水平井平均单井产气量比该区块常规水平井高0.49×104 m3/d,其工厂化钻井完井技术可为国内非常规气藏水平井工厂化作业提供借鉴。Abstract: The Sulige gas field belongs to the largest tight sandstone gas reservoir in China, and Su 53 is the only block in which horizontal wells have been implemented in integrated development. In order to improve the development efficiency at a low cost, and following the previous practice and experience of advanced factory operations experience both domestically and abroad, suitable factory drilling and completion techniques for Sulige gas field have been determined by regional geological research, which optimize the design scheme and the construction management. The key technologies include geosteering for horizontal wells, drilling and reservoir stimulation. Geosteering technology can better guide horizontal wells accurately into the target zones with high efficiency by improving the geological model and adjusting the well trajectory. Drilling technology includes optimizing the casing program and well trajectory, optimizing PDC bits and drilling fluid system as well as designing the drilling rig move on a rail system. Reservoir stimulation technique integrates the volume fracturing into synchronous fracturing to improve producing reserves according to the regional geological characteristics and drilling parameters. Through the implementation of factory drilling and completion in Su 53 Block, the drilling cycle of the average single well was shortened for 15.98 days, the drilling payzone rate raised 4.9% points, and the gas production increased 4 900 cubic meters per day respectively compared with traditional horizontal wells. The factory drilling and completion techniques could provide a new paradigm for domestic unconventional gas reservoir development with horizontal wells.