顺北油气田超深高温水平井井眼轨迹控制技术

顺北油气田储层埋藏深、井底温度和压力高，导致MWD仪器故障率高，超深高温水平井下部高温井段有时无MWD仪器可用，井眼轨迹控制难度较大。为了降低该油气田超深高温水平井轨迹控制难度并提高钻井效率，对水平井井眼轨道设计与井眼轨迹控制进行一体化规划，将顺北油气田超深高温水平井井眼轨道设计成造斜率“前高后低”的多圆弧轨道，优化钻具组合和钻进参数；对于下部无MWD仪器可用的高温井段，采用单弯单稳定器螺杆钻具组合进行复合钻进，以控制井眼轨迹。研究和应用结果表明，采用单弯单稳定器螺杆钻具组合进行复合钻进，根据复合钻进井斜角变化率预测结果优化钻具组合和钻进参数，可以解决顺北油气田超深高温水平井下部高温井段无法应用MWD控制井眼轨迹的问题，降低井眼轨迹控制难度，提高钻井效率。 

Wellbore Trajectory Control Technologies for Ultra-Deep and High-Temperature Horizontal Wells in the Shunbei Oil & Gas Field

The failure rate of Measure While Drilling (MWD) instruments is high in the Shunbei Oil&Gas Field due to deep buried reservoir and high bottom-hole temperature and pressure. The MWD instruments are often not available in high temperature section of horizontal wells and the wellbore trajectory is difficult to control. In order to reduce the difficulty of wellbore trajectory control and improve the drilling efficiency of ultra-deep and high-temperature horizontal wells in the Shunbei Oil&Gas Field, this study integrated wellbore trajectory design and control technology. The wellbore trajectory was designed as multiple circular arcs with higher build-up rates in upper section and lower build-up rates in lower section to optimize the bottom hole assembly (BHA) and drilling parameters. A Positive Displacement Motor (PDM) with single bend and stabilizer was applied for compound drilling and controlling the wellbore trajectory when no MWD instrument was available in the lower high-temperature section. The research and field applications demonstrated that adopting the above compound drilling and optimizing BHA and drilling parameters according to the predicted well inclination variation rates, the inability to apply MWD for wellbore trajectory control can be solved. And in this way, the difficulties in wellbore trajectory control was lowered, and the drilling efficiency is highly improved.