Abstract:  A grain trajectory model was developed based on spatial motion analysis. The relationships between grinding marks and various process parameters were discussed and the concept of grinding marks density was put forward in order to evaluate the marks. The influence of grinding marks on the lubricating and sealing performance was analyzed, and the favorable marks together with the parameter control methods were discussed. Optimizing parameters were presented based on the analysis. The model was validated by the experiments. The results show that the shape and distribution of grinding marks are determined by both the process parameters and structural parameters. For higher surface quality and favorable grinding marks which benefit lubricating and sealing, the parameters and system parameters need to be reasonably selected.

Key words: sphere grinding, grinding marks, grains trajectories, grinding marks analysis