玛北油田玛2井区水平井三开优快钻井技术

High-quality and Fast Drilling Technology in Third Spud of Horizontal Wells in Wellblock Ma 2 of Mabei Oilfield

玛2井区水平井井身结构均为三开结构,主要开发T;b;(百口泉组二段第二层T;小层)致密砂砾岩油气资源。玛2井区三开施工主要难点是造斜段钻遇大段褐色泥岩,钻头优选困难,机械钻速低,褐色泥岩易吸水膨胀缩径,易坍塌失稳;三开密度窗口窄,水平段微裂缝发育,易发生井漏;水平段长,井眼清洁难度大。通过对玛2井区施工的同类型井进行全面分析总结,提炼出了一套优快钻井方法,显著改善了褐色泥岩井段的机械钻速,减少了井下复杂,提高了钻井速度。

The wellbore structure of horizontal wells in Ma2 well block is three spud structure, and they are used to develop the tight sandy conglomerate oil and gas resources in T;b;(small layer T;of the second layer of the second member of Baikouquan formation).The main difficulties in the third spud in Ma2 well block are: a large section of brown mudstone is encountered in the deviation section,therefore, it is difficult to select bit, the mechanical ROP is low, the brown mudstone is easy to absorb water, expand and shrink to lead to collapse and instability;the density window is narrow in third spud, and the micro fractures in the horizontal segment are developed,which is easily to lead to lost circulation;The borehole cleaning is difficult due to long horizontal segment. Through the comprehensive analysis of the same type of wells constructed in Ma 2 well block, a set of excellent and fast drilling methods and experience are extracted, which significantly improves the mechanical ROP of brown mudstone well section and reduces the downhole complexity.