长裸眼井筒强化钻井液技术

Strengthening wellbore fluid techniques for long open-hole

潘丽娟 刘彪

Pan Lijuan Liu Biao

中国石化 西北油田分公司 石油工程技术研究院, 乌鲁木齐 830011

Research Institute of Engineering Technology, SINOPEC Northwest Company, Urumqi, Xinjiang 830011, China

X1井区长裸眼钻井液技术难点集中在上部二叠系火成岩微裂缝发育易漏、下部志留系等硬脆性泥岩易塌，同一裸眼钻井液维护处理难度大。该区X1-1H井二叠系8个漏点、井漏25次，累漏钻井液2 568 m3；X1井志留系泥岩掉块阻卡划眼处理22.1 d。使用聚合物胶凝堵漏剂和竹纤维等，研发随钻防漏配方，0.69 MPa/30 min承压无漏失；研发针对1 mm、2 mm、3 mm裂缝的随钻堵漏配方，承压6.9 MPa；协同成膜隔离-抑制水化作用，优化形成钾胺基成膜钻井液，150℃高温高压滤失量8.8 mL，泥岩滚动回收率较KCl聚磺钻井液提高15.1%。在X1-5H、X1-6H 2口井应用效果显著，二叠系钻进及中完过程无漏失，近5 000 m长裸眼无泥岩阻卡等复杂情况发生，志留系平均井径扩大率仅9.01%。长裸眼井筒强化钻井液技术对X1井区降本增效意义重大。

The difficulty of strengthening wellbore fluid for long open-hole in X1 region is concentrated in the leakage in the upper Permian igneous rocks with developed micro fractures, and the shale collapse in the lower Silurian. Drilling fluid maintenance is difficult in the same open hole section. In well X1-1H, 8 leak points were found in Permian, and well leaked for 25 times, losing 2 568 m3 drilling fluid. In well X1, the treatment for mudstone blocking in Silurian took 22.1 days. Polymer gel plugging agent and bamboo fiber were applied to prevent leakage for 30 min at 0.69 MPa. Plugging agents for fractures of 1, 2, 3 mm were designed, which can prevent leakage at 6.9 MPa. We combined isolating membrane with hydration inhibition, introduced film-forming agent and polyamine inhibitor as key agents, and optimized form Amino potassium filming drilling fluid system for Silurian, which has a high pressure filtration volume of 8.8 mL at 150℃. Compared with KCl-polymer sulfonated drilling fluid, shale recovery increased by 15.1%. Applications in wells X1-5H and X1-6H 2 showed a good effect. No leaking occurred when drilling and completing in Permian. Almost 5 000 meters long open-hole did not stick. The average hole enlargement of Silurian was only 9.01%. Strengthening wellbore fluid techniques for long open-hole are significant to cut cost and increase profit in X1 region.

https://doi.org/10.11781/sysydz2016S1078