准噶尔盆地南缘井壁失稳机理及对策研究

Research on the Mechanism and Countermeasures of Shaft Instability in the Southern Margin of Junggar Basin

孙金声 李锐 王韧 屈沅治 黄宏军

SUNJinsheng LIRui WANGRen QUYuanzhi HUANGHongjun

西南石油大学化学化工学院，四川 成都 610500 中国石油集团工程技术研究院有限公司，北京 昌平 102206

School of Chemistry & Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500, China CNPC Engineering Technology R & D Company Limited, Changping, Beijing 102206, China

准噶尔盆地南缘深层钻井存在高温高压、井壁失稳等难题，现用油基钻井液技术面临巨大挑战。根据呼探1井复杂情况统计，基于对失稳地层岩样组构及特征的分析，揭示了井壁失稳机理。结合南缘深层钻井液技术需求，优选自主研发的纳米封堵剂、超细碳酸钙和弹性石墨形成粒度级配，构建了可有效封堵0.05~50.00μm地层孔缝的油基钻井液体系，该体系180 ℃热滚后高温高压滤失量仅2.8 mL，并可抗20%复合盐水及5%硫酸钙污染，为南缘深层钻井提供了重要技术支撑。

Deep drilling in the southern margin of the Junggar Basin has problems such as high temperature and high pressure and instability of the borehole wall. The current oil-based drilling fluid technology is faced with huge challenges. According to the statistics of the complex situation of Well Hutan 1, based on the analysis of the fabric and characteristics of the rock samples of the unstable formation, the mechanism of the instability of the borehole wall is revealed. Combined with the technical requirements of deep drilling fluids in the southern margin, the self-developed nano plugging agent and super fine calcium carbonate and elastic graphite form a particle size gradation, constructing an oil-based drilling fluid system that can effectively seal the pores and fractures of the 0.05~50.00μm formation, the fluid loss of this system is only 2.8 mL after hot rolling at 180 ℃, and it is resistant to the 20% composite brine and 5% calcium sulfate pollution and can provide important technical support for deep drilling in the southern margin.

10.11885/j.issn.1674-5086.2021.09.10.02