牙轮钻头变曲率滑动轴承的结构分析与摩擦学性能研究

Theoretical Analysis of Structure and Experimental Investigation of Tribological Behavior of Curvature-changing Journal Bearing in the Rock Bit

基于摩擦学原理和接触力学理论 ,提出了可在牙轮钻头滑动轴承中采用变曲率结构 .在不考虑摩擦的情况下 ,就结构设计和配合关系等问题进行了分析讨论 ,划分了准变曲率、吻合变曲率以及间隙变曲率等 3种结构形式 ;针对考虑摩擦时的变曲率结构 ,提出了接触形状优化和预磨合的实施方案 .钻头轴承试验结果表明 ,无论是预设计变曲率还是预磨合变曲率 ,都能改善轴承摩擦副的摩擦学特性 ,因而值得进一步研究和推广 .

Based on the tribological principle and the theory of contact mechanics, it is feasible to adopt curvature changing structure in the Rock bit journal bearing system. The structure and coupling relationship of curvature changing journal bearing under the condition without friction have been analyzed and three kinds of sub form structure configurations, namely, the pseudo curvature changing structure, the conformable curvature changing structure, and the clearance curvature changing structure, been differentiated according to the contacting features. The shape optimization and pre running in regulations of the contact surface of curvature changing journal bearing under friction condition have been established. The results of Rock bit journal bearing test indicate that the tribological behavior of the bearing can be effectively improved by curvature change based on both designing and pre running in.