自动寻向旋转钻具钻进南海8600m大位移井

南海油田XJ24－3－A18井是1口井深8600m、水平位移7500m、垂深2740m的大位移井，当井深达到7000m以后，旋转钻井方式的井斜控制难度大，同时产生方位漂移，若改成滑动钻井方式，则钻进摩阻大，钻进难且机械钻速低；当钻进到6871m时，改变了钻具结构，下入了“Power Drive”旋转钻井导向工具。应用表明，钻进中钻井参变化不大，井斜和方位变化均匀、控制井斜和方位比较成功，不产生漂移、狗腿度低，机械钻速提高近10倍，经济效益显著，真正达到了安全、平稳、高效、低耗。

Drilling the 8600m Large Extended Reach Well with Steerable Rotary Drills in the South China Sea

Well XJ24 3 A18 of South China Sea Oilfield is an extended reach well with a TD of 1800m, horizontal displacement of 7500m, and a VD of 2740m. When a well is drilled to 7000m, hole deviation becomes very difficult to control under rotary drilling, and drifting will occur at the same time. As for slide drilling, it produces high friction, and drilling is difficult and low ROP is achieved. A steerable rotary drilling tool called power drive is run into the well in 6871m, and it achieved good results without changing the drilling parameters too much. Static inclination and azimuth changed evenly, no drifting was found and no severe dog legs were made. ROP was almost improved 10 times, and the total costs were reduced therefore.