邛西构造钻井提速问题探讨

RESEARCH ON IMPROVING DRILLING SPEED IN QIONGXI CONFORMATION

邛西构造钻井地层压力系数横向变化大、防塌液柱压力高、须家河研磨性硬地层井段长等情况,引起实钻中的过平衡钻井和井下阻卡以及钻头消耗大、钻井周期长等突出问题,针对这些问题提出的技术措施是按地质层位不同的地层特点,有针对性地应用不同的钻井液体系能够有效控制井壁垮塌;在能控制井壁稳定的情况下建议采用文中推荐的第一种井身结构;采用文中推荐的钻头序列可以大幅度减少起下钻时间;试验气体钻井解决关键井段的提速问题。在邛西构造钻井作业过程中探索试验收到很好效果。

During drilling,some problems were occurred,such as overbalanced drilling,bit freezing,bit wear and tear and long drilling cycle etc.because of the large horizontal change of reservoir pressure coefficient,high fluid column pressure and the long well section of hard formation with abrasive property in Qiongxi structure.Aimed at these problems,some technical measures were put forward,i.e.based on different formation features,different drilling fluid system can control effectively hole collapse;under the condition of hole stability,adopting the first recommendatory casing programme in the paper.Using recommendatory bit sequence can reduce time on trips.Gas drilling solved the problem of improving drilling speed in key well section.