塔里木盆地顺北地区长裸眼钻井液技术

Drilling Fluid Technology of Long Open Hole Section in Shunbei Area of Tarim Basin

摘要:

顺北地区超深井二开裸眼井段长超过5000 m。针对长裸眼井段水敏和膏质泥岩缩径阻卡、二叠系火成岩漏失和垮塌、高摩阻等技术难题，开展了钻井液体系配方优化研究。通过抑制性膨胀试验、抗盐降滤失剂优选试验、复合封堵剂屏蔽封堵试验以及复合润滑剂配比和降摩阻试验，研制了强抑制高封堵低摩阻钾胺基钻井液体系。室内试验表明，二叠系火成岩在该钻井液中的滚动回收率和线性膨胀率分别达到95.09%和1.86%，钻井液能够承受5%NaCl、2?SO4和20%的钻屑污染。该钻井液体系在顺北1-2H井进行了现场试验，其长裸眼井段平均井径扩大率仅为13.55%，漏失量比顺北1-1H井降低了83.8%，复杂时间比顺北1-1H井减少了30.5 d。强抑制高封堵低摩阻钾胺基钻井液有效地解决了顺北地区长裸眼钻进技术难题，具有广阔的推广应用前景。

Abstract:

The length of the second open hole section is more than 5000m in the ultra-deep well of Shunbei area. Aiming at the technical problems, water sensitivity and pipe sticking of hole shrinkage in creaming mudstone of long open hole section, the leakage and collapse of Permian igneous rock and high friction, the optimization of drilling fluid formula was carried out. Through the tests of inhibition expansion, salt-resistant fluid loss control agent selection, shielding and plugging test of compound plugging agent, friction reducing test of compound lubricant ratio optimization, a highly inhibitive high-seal low-friction potassium amine drilling fluid system was developed. The indoor test showed that the rolling recovery and linear expansion of the Permian igneous rocks reach 95.09% and 1.86% in the drilling fluid, respectively, and the drilling fluid can withstand 5%NaCl, 2?SO4 and 20% drill cuttings contamination. The drilling fluid system was tested in Shunbei 1-2H. The average hole diameter enlargement rate of the open hole was only 13.55%, and the leakage loss was 83.8% lower than that of the Shunbei 1-1H well, complex period was decreased by 30.5 days in comparison with well Shunbei 1-1H. The application of high performance of inhibition and sealing potassium-amine polysulfonated drilling fluid effectively solved the problems in long open hole drilling process, which has broad prospects for application.