涡喷发动机高温高速轴承失效机理及改进措施

介绍了涡喷发动机高温高速轴承中导引面严重磨损和轴承的热失稳等失效形式的特征 ,分析了保持架和内圈引导面之间“软磨硬”的异常磨损失效机理 ,指出“软磨硬”是由轴承保持架内引导面对套圈的高速高频振动造成的 ,轴承引导面材料摩擦性能不匹配和润滑油严重污染加速了磨损进程。同时 ,从轴承的性能参数方面分析了轴承的热失稳产生的原因。台架模拟实验再现了导引面严重磨损的主要失效形式 ,提出并实验验证了采用陶瓷轴承和导引面材料改性技术克服异常磨损的技术措施

Failure Mechanism and Improvement Measures of High-temperature and High-speed Ball Bearings for Turbojet Engine

Ball bearings in missile turbojet engines operate under the conditions of high temperature and high speed. In this paper, the bearing failure characteristics which include heavy abrasion between the retainer and ring on the guide surface and thermal instability are introduced. The abnormal impact abrasive failure type which is called "the hard worn by the soft" and occurs between the retainer and rings in the guide plane is analyzed. It is pointed out that "the hard worn by the soft" is caused by high speed and high frequency vibration between the guide surfaces of the retainer and rings and tribological incompatiblity of materials, and accelerated by oil contamination. The reasons for bearing thermal instability are also presented. The failure type "the hard worn by the soft" is recurred and verified by the simulation tests. The paper also proposes some methods such as using ceramic bearing or guide surface modification to restrain the abnormal wear failure which have been proved effective by tests.