对钻柱在反转情况下横向振动规律的研究

STUDY ON THE LATERAL VIBRATION RULE OF DRILLING STRING UNDER REVERSION

目前对钻柱横向振动的研究基本上忽略了横向振动的激发来源和轴向力的存在。文章针对钻井工程中钻柱横向振动的实际情况,建立力学模型。从理论上分析了轴向载荷存在的情况下钻柱横向自由振动的规律,获得了钻柱横向振动固有频率。提出了钻柱反转自激横向振动,分析了钻柱的横向最大弯曲挠度、弯曲应力与钻柱的横向固有频率的关系。为进一步解决钻柱的横向振动问题奠定了基础。

At present, axial load and excited origin of drilling string lateral vibration is usually neglected. This paper analyzed the practical situation of drilling string lateral vibration during drilling, established mechanical model. The rule of lateral vibration under axial load was studied in theory, the inherent frequency of drilling string was obtained. Moreover, self-excited whirling lateral vibration was studied. The relations among maximal lateral flexibility, bending stress and inherent frequency were analyzed. The common method is given about resolving the problem of drilling string lateral vibration.