Influence of lapping trajectory on the surface roughness of cylindrical roller: modeling, simulation, and experiments

The uniformity of the lapping trajectory is a crucial criterion to determine the processing quality. The relationship between the uniformity of the lapping trajectory and the surface roughness in precision lapping of cylindrical rollers was investigated. Based on the principle of geometry and kinematics, the parametric equations of lapping trajectory points are established, and the trajectory simulation is carried out. The standard deviation of trajectory density in different sections is employed to evaluate the trajectory uniformity. Subsequently, a prediction model for surface roughness R_a based on the cutting depth of undeformed abrasive particle was established, and its accuracy was validated through experiments. Finally, based on the insights gained from simulations and experiments, the correlation between the uniformity of the lapping trajectory and surface roughness was analyzed. It is found that the variation of trajectory density and distribution results in the difference of surface roughness uniformity under different motion parameters. The result shows that the standard deviation of trajectory uniformity can reflect the uniformity of roller surface roughness numerically. Under selected parameter combinations, the average surface roughness of the cylindrical roller significantly decreased from the initial 154.6 ± 15 to 25.3 ± 3.5 nm after 20 min of lapping.