在役钻柱的纵向振动模型的分析与研究

钻柱振动分析是一个非常复杂的动力学问题，也是国内外钻井界正在深入研究的问题。实际钻井中的钻柱振动可能是纵向振动、横向振动或扭转振动以及它们相互祸合的振动，钻柱的疲劳破坏、粘扣现象和大部分刺扣泄漏事故也都与钻柱振动有直接关系，特别是与钻柱的纵向振动有关，为减少纵向振动在钻井过程中的危害，优化钻具组合避免纵向共振，建立了钻柱的纵向振动模型并给出了相应的边界条件、初始条件和振动方程，为进一步研究钻柱的振动问题打下基础。

Analysis on Longitudinal Vibration of Drilling Strings in Service

Analysis on vibration of drilling strings is a very complex problem, which is deeply studied in well drilling industry both at home and abroad. In fact drill string vibration may be longitudinal, lateral and torsional one combined by both, accidents, such as fatigue failure, thread gluing and its piercement are directly related with the vibration, especially with its longitudinal vibration. In order to reduce the hazards caused by longitudinal vibration in drilling process, bottomhole assembly is optimized to avoid the longitudinal vibration, a model of drilling string for longitudinal vibration is established and corresponding boundary conditions, initial conditions and vibration equations are provided, bases are provided for a further study of drilling string vibrations.