YM7-H1超深水平井施工困难及其原因分析

分析了YM7-H1超深水平井施工的技术难点，重点介绍了在施工过程中遇到的定向侧钻、滑动钻进、粘卡、缩径、“反阶梯”井眼轨迹的控制、套管变形等主要难题及解决办法，对施工困难的原因进行了分析和总结，并探讨了解决这些问题的技术措施，从中得出：要避免在大尺寸井段用滑动钻进方式造斜；超深水平井做好钻井设计非常重要；在钻井液密度高、裸眼井段长、井眼光滑性不好等不利条件下，粘卡、加压困难、动力钻具功率得不到有效发挥等问题会随之出现，这时若采用滑动钻进方式钻进应优先使用牙轮钻头；进行有效、快速、果断地决策是钻井安全的有力保证等一些重要的结论和建议，对以后在该区块钻含膏泥岩层超深水平井有很好的借鉴意义。

Drilling Difficulties and Analyses in Ultra-Deep Horizontal Well YM7-H1

This paper analyzes technical difficulties in drilling the ultra-deep horizontal well of YM7-H1, emphasizes main troubles and solutions of directional side tracking, sliding drilling, sticking, tight hole, reverse-step well path control, casing deformations, discusses technical measures for solving above mentioned issues, and draws the following conclusions; to avoid building up by sliding drilling in large hole sections, detailed plan for ultra deep horizontal wells is very significant, cone bits should be given priority while sliding drilling in a long open hole with high mud density because of bad hole lubricity, sticking, lower WOB, and lower mud motor powers, quick and decisive decisions would guarantee safety drilling. These conclusions give good references for ultra-deep horizontal drilling in gypsum and shale formations in the block.