Effect of Lubricant on Wear Debris Color Diagnosis

Abstract

Color feature of debris is quite often used for source diagnosis in machine component while performing wear debris analysis (WDA). This feature is commonly observed and analyzed with different offline debris imaging setups. In these setups, its attributes remain consistent in their values as just a colorless medium i.e. air is in between the imaging setup and the observed debris. But in the case of an online debris analysis, the measurements of these attributes can be affected as the imaging has to perform in the presence of a machine lubricant. The lubricant color can affect the measurement of debris original color attributes and further can cause a wrong source diagnosis. In this paper, the effects of lubricant color on debris color measurements are discussed. A debris imaging setup is used for experimentation. Micro size steel debris are analyzed with three different lubricants. The debris color measurements are initially performed in an offline mode when the debris are placed on a glass slide. Later the mentioned measurements are taken in the presence of lubricants when the debris are flowing with the lubricant medium via a flow cell. Finally a comparison is made which concludes that the darker the lubricant the lesser will be chances to deduce the material (color and attributes). Whereas brighter lubricants do not hinder the analysis and identification of material and hence are considered suitable for qualitative wear debris analysis.