推靠式旋转导向工具造斜能力影响因素

旋转导向工具相比于滑动导向工具具有机械钻速快、摩阻扭矩小、水平位移延伸能力强、井眼轨迹易调控等优点。推靠式旋转导向工具引入国内市场后，总体应用情况较好，但在部分地区也出现了工具造斜能力不足的问题。根据底部钻具组合纵横弯曲梁方法，建立了推靠式旋转导向工具变截面BHA力学模型以及井斜趋势角分析模型，并在此基础上分析了BHA结构参数、钻压、钻头各向异性和岩石可钻性对工具造斜能力的影响规律。分析结果表明，偏置力、第1跨钻柱长度及外径、第2跨钻柱外径、钻头侧向切削能力对工具造斜能力的影响较大。根据分析结果对推靠式旋转导向工具的底部钻具结构进行了优化，在塔中地区取得了较好的应用效果。

The influencing factors of the inclination ability of push-the-bit rotary guiding tool

Compared with slide steering tools, rotary steering tools are more advantageous with high rate of penetration (ROP), small drag and torque, strong horizontal displacement extension ability and flexible well trajectory control. After the push-the-bit rotary steering tool is introduced into domestic markets, its application is overall better, but in some areas, it presents the problem of insufficient buildup capacity. In this paper, variable cross-section BHA (bottom hole assembly) mechanical model and well deviation trend angle analysis model for push-the-bit rotary steering tool were established by means of the BHA beam-column method. And based on this, the influential laws of BHA structure parameters, weight on bit (WOB), bit anisotropy and rock drillability on the buildup capacity of the tool were analyzed. It is indicated that the buildup capacity of the tool is affected more by bias force, length and outer diameter of the first span drilling string, outer diameter of the second span drilling string and lateral cutting capacity of drilling bit. Finally, the BHA of push-the-bit rotary steering tool was structurally optimized based on the analysis results. And its application effect in Tazhong area is better.