Jim Fitch & Holly Borden
P/PM Technology magazine
The majority of wear related failures occur as the direct result of particulate contamination. A recent article published in Lubrication Engineering magazine concludes that more than 82% of wear related losses are contaminant induced. And, the largest portion of this is abrasive wear; the direct result of particles wedged between rolling and sliding surfaces.
According to work done by SKF, bearings can have “infinite life” when the influence of particle contamination is eliminated. In some cases more than a 75-times life extension can be achieved by maintaining exceedingly clean lubricating fluids. It is also worth noting that the penalty associated with a contaminated lubricant is identical to that of using a lubricant with just 25% of the recommended viscosity.
There are few forms of internal machine failure that don’t release particles into the lubricant; detecting increases in particle contamination can be extremely important. Figure 1 lists some of the failure types detectable using contaminant monitoring.
As a predictive maintenance technique, abnormal particle trends are the early symptoms of several non-particle induced conditions. Once the abnormal trends are recognized, a more precise assessment of lubricant condition or machine malfunction can be pursued.