Wear and Life Prediction of CAM Roller Follower 940822

Experimental and analytical research were performed on the contact fatigue wear of cam roller follower (needle roller bearing). A new fatigue test machine with a special two-bar loading system was designed to increase the efficiency and the reliability of the tests. The performance test indicated that the end clearance between the roller and rocker had a significant influence on friction and heat generation in the roller follower. The nondestructive testing procedure showed that there were possibly three wear mechanisms in the wear process, but the dominant one was subsurface crack initiation and propagation. Based on the observed wear mechanism two crack initiation dominate contact fatigue models were used to predict the wear life. The life prediction parameters were determined from statistic analysis of the experiment data. The Lundberg-Palmgren model [1] predicts shorter lives and dose not fit with the experiment data. The Ioannides-Harris model [2] correlates closely with the test results.