Benefits of lubricant oil analysis for maintenance decision support: a case study

Often, maintenance managers face challenges in making maintenance decisions due to the lack of sufficient and accurate information. It's not uncommon for the current problem to be resolved, but the cause of the problem remains, which is why some types of failures often recur, reducing the equipment availability and generating additional costs. To overcome these challenges, modern maintenance principles are based on the application of the equipment condition monitoring techniques. One of these techniques is used oil analysis also known as lubricant condition monitoring, which yields an insight into the physical and chemical state of the lubricating oil, as well as the condition of the machine elements that come in contact with oil during routine operation. To illustrate the benefits of employing this technique, a case study of asphalt paving machine is presented. In the case study, four basic lubricant parameters (viscosity, water content, solid particulate content and acid number) for the hydraulic system were analysed. The results of the analysis show a sudden increase in the solid particles content, due to which certain maintenance interventions had to be taken to avoid failure of the system and unnecessary maintenance costs. Also, by oil condition monitoring, after two years, maintenance staff received information which is the base for making a decision on the appropriate replacement interval of hydraulic oil.