桩66区块长裸眼防塌钻井液技术

Anti-sloughing Drilling Fluid Technology for Long Open Hole in Zhuang 66 Block

桩66区块位于济阳坳陷沾化凹陷五号桩披覆构造带,上部地层发育近3 000 m强水敏泥页岩,施工中起下钻遇阻等复杂情况频发;下部沙河街组层理及微细裂缝发育,井壁失稳严重。针对地层岩性和钻井液技术难点,优选了聚胺强抑制润滑防塌钻井液体系,该体系在桩66区块进行了现场应用,辅助现场钻井液维护处理工艺,保证了工程的顺利进行,钻进过程中井壁稳定,井身质量好,机械钻速高,取得了良好的应用效果.

Zhuang 66 Block is located in Wuhaozhuang drape structural belt in Zhanhua Sag of Jiy-ang Depression.Complex situation like blockage during tripping often occurs during the course of drilling,because a long section of strong water sensitive shale is developed in the upper stratum with a depth of nearly 3000 m.The borehole wall is very instable in Shahejie Formation because of bed-ding and microfracture development.In view of the formation lithology and drilling fluid technical dif-ficulties,the polyamine drilling fluid system with strong inhibition,lubrication and anti-sloughing is chosen and applied to Zhuang 66 Block.Under the help of corresponding drilling fluid maintenance and treatment techniques,the well is drilled smoothly and well bore quality is good,the ROP is high,and good application effect has been achieved.