煤层气多分支水平井轨迹控制技术

多分支水平井因能够有效提高煤层气产能而成为煤层气开采的主要井型，但由于技术和经验不足，在钻井施工过程中，钻速慢、井下复杂情况时有发生。文中分析了多分支水平井在各个阶段的轨迹控制难点，并探讨了悬空侧钻、老眼重入等技术难点及控制要点，给出了造斜段轨道设计运算过程，通过合理选择随钻测量系统，精确控制了钻井全过程轨迹参数。该井眼轨迹的精确控制为我国煤层气多分支水平井整套工艺的施工提供可靠的技术借鉴和准确的参考数据。

Coalbed methane multi-branch horizontal well trajectory control technology

In recent years, multi-branch horizontal well has become the most important well type for coal bed methane（CBM）development because it can effectively enhance CBM production. But lacking skill and experience often cause slow drilling, sticking accidents, and other complex situations underground. The paper makes a comprehensive analysis on the trajectory control difficulties at each stage of multi-branch horizontal well drilling, and gives build-up section track design operation process. Through selecting a reasonable MWD system, the trajectory parameters of the whole drilling process is precisely controlled. The article also explores pending sidetracking, old well bores reentrant technical difficulties and control points. It provides reliable technical reference and accurate referencing data for drilling coalbed methane multi-branch horizontal wells.