对不同轴式下部钻具组合动态特性的初探与思考

地面驱动的带弯角或偏轴的不同轴式导向钻具和防斜钻具组合已经广泛应用于水平井、大斜度井、大位移井、分支井和直井钻进中。由于对该类钻具的动态特性和轨道控制理论研究不足,使得应用效果不稳定。欲较好地解决该类钻具的轨道控制问题,必须深入研究该类下部钻具组合的稳定性判别、钻具各点的运动状态判别和参数分析、钻具动力学分析的数学模型和井眼轨道预测方法。本文仅从问题的性质、可能遇到的问题和解决问题的可选途径等方面进行了初步探讨。

A preliminary study on dynamic influencing factors for bottom-hole assembly with bending angle or bias axis

Slide or rotary steering drilling assembly and dropping deviation drilling assembly with bending angle or bias axis have extensively applied in horizontal wells, high-deviated well, extended reach well, multi-lateral well and vertical well, but the application effectiveness is not stable because of the insufficient study of the mechanical characteristics and trajectory control theory for this sort of BHA. In order to resolve the trajectory control problems of this sort of BHA, it is necessary to resolve the steadiness diagnosis, movement state diagnosis and parametric analysis of the BHA, the mathematical model of the dynamic analysis, the dynamic model between bit and formation and trajectory forecasting method. this paper discusses the property of the problems, possibly encountered problems and the resolving method.