Wear Analysis of Cam and Follower Using Finite Element Method

A particular type of contact condition, know as cam and follower contact, exists in the direct valve train system of an engine and is partly responsible for wear. The wear analysis of cam and follower contact system are analyzed with respect to the cam angle and the pressure angle and finite element modeling of cam and follower assembly is done using the ABAQUS analysis software. The contact pressure, von misses' stresses are calculated theoretically and the ABAQUS results are presented in contour plot and numerically. The results showed that the cam rotational angle and the pressure angle had an effect on the contact pressure, on stress distribution and also plays a great role on the surface wear of the contact. The results also showed that the contact pressure, von misses stress and the wear increases with of cam rotational angle and the wear increases linearly with the contact pressure. Based upon the theoretical analyses and ABAQUS analysis, a theoretical model for evaluating the tribological performance of the valve train was developed. A multi-aspect comparison between theoretical and ABAQUS results was made. A good agreement between theoretical and ABAQUS analysis results showed that the model provided a reliable prediction of the tribological characteristics of the cam/roller follower. Three critical portions of the cam could be identified these are the cam basic surface region, cam flank and cam lobe region. The most critical region is the cam lobe region