胜利油田车66区块钻井液技术

DRILLING FLUID TECHNOLOGY FOR CHE 66 BLOCK, SHENGLI OILFIELD

在胜利油田车66区块,由于地层压力系数高,对井下地质情况认识不足,施工井钻井液施工难度大。自2005年初车66井发生严重漏失以来,先后有3口探井发生不同程度的漏失。针对车66区块施工井的特点,采用相应的钻井液工艺技术和配方,上部井段采用抑制性强的聚合物防塌钻井液体系,控制上部地层造浆,防止地层水化膨胀,避免起下钻发生阻卡现象,下部井段采用非渗透聚磺屏蔽封堵钻井液体系,提高地层的承压能力,解决了该地区施工井因安全钻井密度窗口窄而导致上涌下漏的技术难题,给该区块以后的钻井作业提供了一些指导。

Because of high formation pressure coefficient and a less acquaintance with downhole geologic status, it is difficult to operate drilling fluid in Che 66 Block of Shengli oilfield. Leakage has occurred in three prospecting wells since early 2005 after serious leakage happened in well Che 66. According to the characteristics of operating wells, we adopt the special process and formula of drilling fluid. An anti-collapse drilling fluid system with strong resistant polymer is applied to upper well section to control more mud, keep formation from hydrated expansion, and avoid blocking while going in the hole. A non-permeable polysulfonate drilling fluid system with screening and plugging actions is applied to lower well section to increase the formation pressure resistance. That solves the technical problems of well kick and circulation loss resulted from narrow density window in this area, and provides guidelines for the future drilling.