Lubrication safety in high-speed ball-bearings

In a 7206 C high-speed, mist-lubricated ball-bearing, both the film thickness and lubricant parameter λ in ball—race tribo-systems have been analytically investigated in terms of starvation and thermal effects, and good correlations with experimental results were obtained for 5,000 to 35,000 rpm rotational speeds. Including a lubricant parameter in ball—race tribosystems as a safety criterion for ball-bearings, friction losses, temperature, and limit speeds have been correlated with this criterion for a 7206 C ball-bearing. Friction losses in ball-outer race tribosystems have been computed for both EHD and mixed lubrication regimes. The influence of the bricant parameter on friction losses has been shown both theoretically and experimentally. A new speed limit concept including the lubricant parameter λ, has been developed by the authors.