grease We all know about oil analysis and the many benefits that this important technology has brought to operators of all manner of oil lubricated machinery. When combined with other key diagnostic technologies like vibration, infrared and ultrasound, the insight into the operating condition of an oil lubricated component can allow us to make the optimal decisions for operations and maintenance. But what happens when the critical component is grease lubricated? More often than not, we end up with a machine that has one fewer diagnostic tool at our disposal. In some cases, this isn’t that big of a deal, but in others, the missing lubricant info can result in recurring failures as we fail to identify root-causes. In other cases, we are forced to allow the degradation of the machine to progress to the point where irreversible damage has occurred, before the signs of that damage are seen by ultrasound, vibration, or other indications. How much more effective could our diagnostic programs be if we could identify lubricant conditions prior to damage, and correct them pro actively. It happens all the time in oil analysis. For example, when we see high particulate count in an oil reservoir, we may employ supplemental filtration or more effective reservoir breathers to eliminate the abrasive contaminants before they can cause bearing or valve damage. The same type of concerns exist with greases, not only including the presence of particulate contaminants, but also mixing of incompatible greases, changes in grease consistency and other conditions that lead to later machine damage. By focusing on identifying these conditions as they develop, we can reduce or eliminate the component damage and improve equipment reliability. Also, when we know what caused the failure or the condition that could potentially lead to failure, we can address systemic issues such as grease mixing, contaminated bulk grease supplies, or equipment specific operating conditions that require re-evaluating grease types, additives or re lubrication methods or frequencies and quantities. The time is right to consider some of the recent advances in grease sampling and analysis that will allow us to include lubricant analysis for all our critical machinery, not just the ones that happen to be oil lubricated. Excellent research
is ongoing and has demonstrate the capabilities of rheometry in looking for changes in flow characteristics of grease, that can lead to thickening or thinning of greases in service, including conditions that lead to “tunneling�, or softening and loss of base oil from grease, resulting in ineffective lubrication. Sampling advances have opened the doors for trendable analysis of grease lubricated motors, pillow block bearings, gearboxes and other critical components. And other streamlined analysis methods like Die Extrusion can quickly and effectively trend changes in in-service grease condition to address Wear, Consistency, Contamination and Oxidation Conditions. Rich Wurzbach has over 20 years of experience in the development of Predictive Maintenance programs and the applications of diagnostic technologies for industrial equipment. His expertise lies in the applications of Infrared Thermography and Oil and Grease Analysis, and the integration of various diagnostic technologies for equipment assessment. He has worked in the maintenance departments at Peach Bottom Atomic Power Station and the National Institutes of Health. www.mrgcorp.com