大港油田大位移钻井技术研究与实践

STUDY AND PRACTICE OF ERD WELL DRILLING TECHNOLOGIES IN DAGANG OILFIELD

针对大港油田大位移井存在的摩阻和扭矩大、轨迹控制难度大、井壁稳定难度大、长裸眼段下套管难度大、井眼净化要求高等技术难点,研究制定了一套大位移水平井钻、完井技术。论述了大位移水平井实施中的井眼轨迹设计技术、导向钻井技术、漂浮下套管技术、高润滑强抑制的优质钻井液技术、摩阻扭矩预测及监测技术等,已钻成的3口大位移水平井的水平位移与垂深比大于2,其中庄海8Ng-H1井的水垂比为2.74,水平段732 m。实践证明,该套技术在大港油田是完全可行的。

In drilling the ERD wells,in Dagang Oilfield,many difficulties are confronted,such as the high drag and torque,difficult well trajectory control and well wall stability,running casing at long openhole section,high requirement of well cleaning,and so on.In response to this situation,a series of technologies for drilling ERD wells are researched and established.In this paper,the technologies used in the ERD wells drilling operation,including well trajectory control,steering drilling,running casing with floatation collar,high inhibitory & lubricative drilling fluid,drag and torque forecasting and monitoring are discussed.Among the 3 ERD wells drilled,the ratio of horizontal displacement to TVD of each well is greater than 2,the ratio of horizontal displacement to TVD of zhuanghai 8Ng-H1 well is 2.74,and horizontal section is 732m in lenth.The practice shows that all the technologies used in ERD well drilling operation are feasible.