带可控偏心稳定器的下部钻具组合力学特性计算分析

ANALYSIS OF MECHNICAL FEATURES FOR LOW DRILL ASSEMBLY WITH CONTROLLABLE ECCENTRIC STABILIZER

狄勤丰 周凤岐 赵业荣

Di Qinfeng Zhou Fengqi Zhao Yerong

西安石油学院 西北工业大学 长庆石油勘探局

大位移井井眼轨迹的自动控制十分重要,为此国内外都在研究各种井下自动可控的导向工具,可控偏心稳定器就是其中之一。在国内有关理论的基础上,对带可控偏心稳定器的下部钻具组合的力学特性进行了研究。结果表明,当偏心稳定器伸缩块的伸出量随意可控时,钻头上的造斜力随偏心距的增加而增加,随偏心稳定器安装位置的上移而减小,方位力则相反。造斜力随偏心方位角的变化规律近似为半正弦函数,而方位力的变化规律则近似为正弦函数。

It’s extremely important to control automatically the well bore path of large displacement wells. Auto-controlled downhole guide tools, such as controllable eccentric stabilizers, are being developed underway both inside and outside China. This paper studies the mechanical features for lower drill assembly with controllable eccentric stabilizer, based on the relative theory. The study indicates that the deviating force on bit is increased along with increment of the eccentric distance; and the force is reduced along with the upward movement of the eccentric stabilizer. when expansion block movement of the eccentric stabilizer is controlled, but the azimuthal force is opposite from the deviating force. The variation law of deviating force along with the eccentric azimuth is similarly a half sine function, whereas the variation law of the azimuthal force is similarly a sine function.

10.3969/j.issn.1000-7393.1999.04.002