高造斜井眼轨迹控制工具悬臂轴承失效分析与优选

Failure Analysis and Optimization of Cantilever Bearing of Borehole Trajectory Control Devices

高造斜井眼轨迹控制工具提供了高效的多枝导流出砂井钻井手段,该工具在进行井下工况模拟实验时悬臂轴承破坏失效。为分析悬臂轴承的失效机理,基于管柱力学基本理论,建立了主轴力学模型,分析了悬臂轴承在井下工况的力学行为。结合有限元仿真分析,得出了悬臂轴承的失效原因。研究结果表明:主轴弯曲使滚针轴承承受附加弯矩,致其左侧磨损剧烈,轴承径向载荷分布不均,在摩擦扭矩的作用下,保持架发生扭转变形,从而导致悬臂轴承失效。结合分析结果给出了推荐使用的悬臂轴承型号,能有效提高井眼轨迹控制工具轴承使用寿命。

The tool,which is used in borehole trajectory control devices in highly deviated wells,an effective method for drilling to the multibranched diversion in sandy well was given. When testing the downhole tools,the damage and failure of cantilever bearing have been found. In order to analyze the failure mechanism of the cantilever bearing,and based on theory of pipe string mechanics,the mechanical model of the spindle was established,then the mechanical behavior of the cantilever bearing under the working condition was analyzed. The failure reason of the cantilever bearing was obtained by the finite element simulation analysis. As the research shows,the deformation of basic shaft makes abrasion on the needle bearing that the left of it is worse than the right. The deformation of basic shaft cause radialinternal clearance of needle bearing and pre-tighten load,which make the bearing resist unequal force that generates unbalanceloading. Under the action of the friction torque,the holder has a torsion deformation,which leads to the failure of the cantilever bearing. Combined with the analysis results,the model of the cantilever bearing is presented,which can effectively improve the life of the bearing.