渤斜931井复杂地层钻井液体系研究

Drilling fluid technology about complex formation in Boxie 931 well

渤斜931井造斜点浅、稳斜段长、水平位移大,钻井液井眼净化及润滑防卡技术难度大;三开斜井段地层岩性复杂,钻井液稳定井壁技术难度大;钻井液体系与地层岩石匹配性差,钻井时效低。针对地层岩性和钻井液技术难点,通过优选钻井液处理剂,形成了聚胺复合盐润滑防塌钻井液体系,现场施工中针对不同地层采用相应的钻井液维护处理工艺,钻进过程中井壁稳定、井身质量好,钻井时效高,取得了优快钻井的良好效果。

Boxie 931 well was an important directional evaluation well belonged to the engineering company.The deviation point of the well was shallow,the stable deviation section and the horizontal displacement were very long.The technology difficulty of purifing and lubricating borehole was very great.Multiple sets of strata were drilled in the third inclined sections.Due to the above reasons,the technology difficult about drilling fluid was very great to stabilize the wellbore.Aiming at the formation lithology and technical difficulties of drilling fluid,the drilling fluid treatment agent was optimized,the polyamine and composite salt drilling fluid system with lubricating and anti-caving ability was formed.According to different formation lithology,corresponding drilling fluid construction technic was adopted to ensure the smooth construction of the well.The borehole wall was stable during the course of drilling,the wellbore quality was good,and the drill effectiveness was high.At last,the good effect of excellent and fast drilling was achieved.