On the running-in behavior of cam-follower mechanism

A line contact thermo-elasto-hydrodynamics analysis is developed to study the behavior of the cam-and- follower contact. The elasto-plastic model takes into account the asperity pressure and asperities' flattening due to plastic deformation. The modified Reynolds equation is solved to predict the hydrodynamic pressure. The change in the surface roughness and friction coefficient during the running-in period is taken into account with provision for thermal effects. The results show that the performance parameters of the cam-follower during the running-in period are strongly affected by the rotational speed and thermal effects. In particular, the variations of film thickness and the frictional force of this mechanism, not hitherto reported in the literature, are discussed in depth. It is shown that the rate of flattening of surface roughness is a crucial factor during the running-in period.