加拿大非常规油气田优快钻井技术

摘要

Due to high cost of unconventional oil/gas ifelds development like tight gas, it is in urgent need to study optimized fast drilling in order to reduce drilling costs. The development of unconventional oil and gas needs to place long horizontal sectionin in the reservoir. In view of the technical challenges like dififculty in control of wellbore trajectory in long horizontal section and low penetra-tion rate, the mechanical properties of bottomhole assembly was analyzed and optimized through computation, and the compound drill-ing rate in the horizontal section was improved, all of which reduced the number of trips in combination with bit selection. The drillstring oscillator was used to improve wob transferring efifciency;oil-based drilling lfuid was specially prepared for horizontal section, which greatly reduced the friction factor and effectively inhibited wellbore instability. The application of optimized fast drilling technology in Daylight Unconventional Oil/Gas Field (Canada) shows that this technology signiifcantly reduces drilling period and drilling costs, and provides useful reference for high-efifcient development of domestic unconventional oil/gas ifelds.%由于致密气等非常规油气田开发成本高，迫切需要进行优快钻井研究降低钻井成本。非常规油气开发需要在储层内布置长水平井段，针对长水平井段井眼轨迹控制困难、机械钻速低的技术难题，通过计算，分析了底部钻具组合力学特性，优化了底部钻具组合，提高水平段复合钻进比例，配合钻头选型，减少了起下钻次数；采用钻柱振荡器提高钻压传递效率，针对水平井段优化配置油基钻井液体系，大幅度降低了摩擦因数，又抑制了井壁失稳。加拿大daylight非常规油气田应用结果表明，应用优快钻井技术大幅度降低了钻井周期和成本，为国内非常规油气田高效开发提供了借鉴。