自升式钻井平台悬臂梁振动特性对钻井作业的影响研究

Research on the influence of vibration characteristics of cantilever beam of jack-up drilling rig on drilling operations

自升式钻井平台悬臂梁振动特性对钻井作业安全影响较大。根据自升式钻井平台悬臂梁的结构特点,通过悬臂梁力学模型,建立了悬臂梁不同外伸距离条件下的自由振动频率方程。计算结果表明:悬臂梁自由振动频率与悬臂梁的弹性模量、惯性矩成正比关系,与悬臂梁集中载荷、跨度、外伸距离成反比关系;悬臂梁覆盖的工作区域内,悬臂梁的共振转速对钻井作业转速影响较大易引发井口工具磨损等复杂情况。本文研究成果可为悬臂梁钻井平台钻井参数的合理选择与设计提供参考。

The vibration characteristics of the cantilever beam of jack-up drilling rig have a great influence on the safety of drilling operations.According to the structural characteristics of the cantilever beam of jack-up drilling rig and by virtue of the cantilever beam mechanics model,the free vibration frequency equations of cantilever beam under different extension distances are established.The calculation results show that the free vibration frequency of the cantilever beam is proportional to the elastic modulus and inertia moment of the cantilever beam,and is inversely proportional to the concentrated load,span and extension distance of cantilever beam;in the working area covered by the cantilever beam,the resonance speed of cantilever beam exerts a great impact on the rotational speed of drilling operations,tending to cause complex conditions such as wellhead tool wear.The research results in this paper can provide a reference for the rational selection and design of drilling parameters for cantilever-type drilling rigs.