Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
788959 | International Journal of Refrigeration | 2007 | 9 Pages |
Abstract
Chlorine free replacement refrigerants, HFC (hydrofluorocarbons) and HC (hydrocarbons), have shown less lubricating properties. Phosphate based additives were used to improve the lubricity with refrigerant R-134a, demonstrating positive effects. In the present paper, the ability to form lubricating film and wear of two additives, phosphate ester and acid phosphate, was investigated in a bearing test apparatus.The results show that phosphate additive in polyolester oil, in an R-134a environment, increases the lubricating film and reduce wear. Surface topography during the initial run-in changes to a more favorable profile with lower RMS angle and longer wavelengths that promote load-carrying capacity and film build-up.
Related Topics
Physical Sciences and Engineering
Engineering
Mechanical Engineering
Authors
Roger Tuomas, Ove Isaksson,