鄂尔多斯盆地神府区块小井眼优快钻井关键技术

Key Technology of Optimized and Fast Slim Hole Drilling in Shenfu Block, Ordos Basin

贾佳 夏忠跃 冯雷 李建 王烊

JIA Jia XIA Zhongyue FENG Lei LI Jian WANG Yang

中海油能源发展股份有限公司工程技术分公司，天津300452

CNOOC EnerTech-Drilling & Production Co., Tianjin, 300452, China

鄂尔多斯盆地神府区块为致密气产区，为进一步提高该区块的机械钻速、降低钻井成本，开展了小井眼优快钻井技术研究。井眼轨道由“直—增—稳—增—稳”优化为与地层走向精确匹配的“直—增—降—稳”，提高了钻井效率；钻头进行了优化设计，改变了钻头布齿密度，调整了钻头切削齿尺寸和后倾角，增强了钻头的稳定性和耐磨性；优化了钻具组合，优选了钻杆尺寸，改进了螺杆钻具，研制了用于提速的三维振动钻井冲击器；研制了仿生润滑剂，改进了钻井液配方，提高了钻井液润滑性能；另外，优化了钻井施工参数，研究形成了小井眼优快钻井关键技术。该技术在神府区块8口井进行了应用，实现了二开一趟钻完钻，机械钻速提高50%以上，钻井周期缩短45%，取得了显著效果。神府区块小井眼优快钻井关键技术为该区块后续致密气井钻井提供了技术支撑，对国内其他地区的致密气井钻井也有借鉴作用。

The Shenfu Block in Ordos Basin is a tight gas-producing area. In this study, optimized and fast drilling technology for slim holes was explored to further increase the rate of penetration (ROP) and reduce the drilling cost in this block. The wellbore trajectory was optimized from "vertical–build–hold–build–hold" to "vertical–build–drop–hold" matching the formation strike, which improved the drilling efficiency. The drill bit was optimized, including the change of tooth density, adjustment of cutting tooth size and caster angle, and enhancement of stability and wear resistance. The drilling assembly, size of the drill pipe, and postive displacement motor (PDM) were optimized, and a three-dimensional (3D) vibration impactor was developed for enhancing the ROP. Additionally, the performance of the drilling fluid was improved by the introduction of a biomimetic lubricant and the optimization of the drilling fluid formula. Further, drilling parameters were also optimized. The key technology of optimized and fast slim hole drilling relying on the above measures was applied in 8 wells in Shenfu Block, realizing the one-trip drilling of the second-spud section. The ROP was increased by more than 50% and the drilling cycle was shortened by 45%. This technology provides technical support for future drilling of tight gas wells in Shenfu Block and a reference for the drilling of tight gas wells in other regions in China.

中国海洋石油集团有限公司创新基金项目“全井段高效复合型钻井提速工具研究与应用”（编号：CNOOC-KY-KJCX-CRI-2017-01）资助

https://doi.org/10.11911/syztjs.2021110