TY - JOUR
TI - Analysis of grease contamination influence on the internal radial clearance of ball bearings by thermographic inspection
AU - Mišković Žarko Z
AU - Mitrović Radivoje M
AU - Stamenić Zoran V
JN - Thermal Science
PY - 2016
VL - 20
IS - 1
SP - 255
EP - 265
PT - Article
AB - One of the most important factors influencing ball bearings service life is  its internal radial clearance. However, this parameter is also very complex  because it depends on applied radial load and ball bearings dimensions,  surface finish and manufacturing materials. Thermal condition of ball  bearings also significantly affects internal radial clearance. Despite many  researches performed in order to find out relevant facts about different  aspects of ball bearings thermal behaviour, only few of them are dealing with  the real working conditions, where high concentration of solid contaminant  particles is present. That’s why the main goal of research presented in this  paper was to establish statistically significant correlation between ball  bearings temperatures, their working time and concentration of contaminant  particles in their grease. Because of especially difficult working  conditions, the typical conveyor idlers bearings were selected as  representative test samples and appropriate solid particles from open pit  coal mines were used as artificial contaminants. Applied experimental  methodology included thermographic inspection, as well as usage of custom  designed test rig for ball bearings service life testing. Finally, by  obtained experimental data processing in advanced software, statistically  significant mathematical correlation between mentioned bearings  characteristics was determined and applied in commonly used internal radial  clearance equation. That is the most important contribution of performed  research - the new equation and methodology for ball bearings internal  clearance determination which could be used for eventual improvement of  existing bearings service life equations. [Projekat Ministarstva nauke  Republike Srbije, br. TR35029 i br. TR14033]