偏心环组对指向式导向系统性能的影响研究

Impact of Decentralized Rings on Directive Rotary Steerable Drilling System

摘要:

指向式旋转导向系统在水平井和定向钻进中广泛应用，它代表了世界钻井技术的最高水平。首先假设偏心环组个数n=2时可以有效增大钻头的偏移范围，然后通过建立旋转心轴的力学模型，分别推导出n=1和n=2时旋转心轴的转角方程和挠曲线方程进行比较，最后得出当n=2时靠近钻头处的转角θ2要大于n=1时钻头处的转角θ1的结论，即安置2个偏心环组可以达到增大钻头偏移范围，减小井眼轨迹曲率半径，优化系统导向性能的目的。最后，对偏心环组B在L3=0的情况下的力学模型进行了优化。

Abstract:

Directive rotary steerable drilling system reprensents the most advanced technology in the world and it has been widely used in the horizontal well and controlled directional well. Firstly it is assumed that 2 decentralized rings could enlarge the deviation angle of bit effectively; then by the establishment of mechanics model of rotation axis, the rotation angle equations and deflection curve equations while n=1 and n=2 were derived respectively for comparison to prove the assumption, that is with 2 decentralized rings, enlargement of bit deviation angle, smaller well trajectory curvature radius and optimized steering performance can be realized; and finally mechanics model of decentralized ring B is optimized under the condition of L3=0