For the cuttings bed is unstable and it is easy to slide into bottomhole,it may be affect drilling speed and drilling safety and is the danger area of hole cleaning in directional drilling.

• 介绍江苏局安徽公司现阶段提高大斜度定向井井眼净化程度的系列技术措施,由于受其有效程度所限偶发井下复杂情况和事故。