Rail Surface Integrity Analysis in Laboratory

Abstract

This study aims to assess the effect of grinding on the surface integrity of rail materials. Two grinding processes (preventive and corrective) were employed along with the corresponding usage scenarios throughout a series of tests. For the purposes of testing, samples in the form of discs were utilised to assess the surface integrity of rails. Testing initially involved introducing some wear on the discs followed by the appropriate grinding process and then further testing to monitor the disc’s performance. More specifically the preventive grinding was utilised in a scenario where rail discs endured normal usage prior to grinding and corrective grinding process was employed in rails discs that had been run for extensive cycles (2.5 times longer compared to normal usage) to generate significant wear before grinding. After the maintenance process all the specimens were further examined to assess their post-grinding performance. The experiments revealed that the aggressive single grinding pass methodology followed in a corrective maintenance approach could lead to undesirable results as the increased heat input, high surface roughness as well as the initial cracks from the prolonged pre-grinding running period could have an adverse effect on the RCF life. This was demonstrated by an almost triple wear rate compared to the “normal” usage scenario during the post-grinding testing.