粗糙表面下牙轮钻头浮动套轴承润滑机理研究

The lubrication mechanism of floating-rig journal bearings under rough surface

以流变学、摩擦学及固体力学为理论依据，在以15．9 mm（8 1/2英寸）牙轮钻头滑动轴承结构的基础上，综合考虑浮动套滑动轴承的特点及牙轮钻头轴承的特殊性，以牙轮钻头轴承系统结构及失效分析、牙轮钻头润滑脂的高温流变性分析结果为研究基础，建立了粗糙表面牙轮钻头浮动套轴承润滑性能参数的数学模型，并对模型进行了求解。通过计算结果分析得出牙轮钻头浮动套轴承内外间隙比在2．0-3．0之间时，有利于浮动套轴承的正常运转，该结论为牙轮钻头浮动套轴承的设计提供了理论和技术基础。

The theories of rheology, tribology and solid mechanics are used to comprehensively take account of the characters of floating-ring journal bearings and the special properties of the bearings for rock bits on the basis of journal bearing structure ofφ215.9 mm (8 1/2 in ) rock bit. According to the results of the bearing system structure and failure analysis and high temperature theological analysis on the lubricant for the rock bit, a mathematical model is established for the lubrication performance parameters of the floating-rig bearings used on rough surface rock bits, and the model is solved. The calculating result indicates that when the clearance ratio from both outside and inside of the floating-ring bearing is between 2.0 and 3.0, it is propitious to normal runnig. The result provides a theoretical and technical basis for designing the floating-ring bearings of rock bits.