Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/957021
20 | March - April 2018 | www . machinerylubrication.com Many years ago, while venturing out into a power plant to take my first oil samples from plant machinery, I was accompanied by a seasoned mechanic. He was there to ensure I didn't do anything detrimental to the machine in my sampling efforts and to top off any reservoirs that were low following the sample being taken. With my dip-tube and stand-off rod method, along with the large, accessible oil-fill cap in the motors, I was able to take most of the samples without a significant drop in the oil level. However, one was close to the lower limit before the sample was taken, so we agreed that it should be topped up. e mechanic looked around and spotted a bucket sitting near the motor. I asked if it was appropriate for that bucket to be used to get new oil to top off the level. Wouldn't it be a bit dirty? e mechanic agreed, pulled a rag out of his back pocket, wiped the inside of the bucket and proceeded to the lube storage room to get his top-up charge of oil. We now know better and realize that the debris in that bucket was going to be flushed into the motor and cause damage to the bearing. e debris undoubtedly contributed to abrasive and fatigue wear, and the life of that bearing was irreparably harmed. Today, the recognition of the damage and machine life reduction produced by dirt and moisture contam- ination has led to an entire industry focused around keeping oils clean. Protecting oil supplies, filtering them when they get dirty and preventing contaminants from entering machines while they are in operation are proven strategies to extend machinery life. e mechanic wiping the bucket with his rag had no way to know just how dirty his bucket really was, relying only on his vision as a measure of cleanliness. erefore, we monitor the effectiveness of our filtration and exclusion efforts through careful oil sampling, particle counting and moisture analysis. Top reliability programs not only sample oil from their machines but also check the cleanliness of new oil supplies, transfer containers and the quality of oil while it is being reme- diated through filtration and separation technologies. What About Grease? It's understood that particles in oil lead to bearing and gear abrasion, three-body cutting wear in plain bearings, and surface fatigue through particle denting in roll- ing-element bearings. A study by the National Research Council of Canada assigned 80 percent of bearing failures to particle-initiated failure modes across several industries. In addition, high water levels in oils contribute Why Grease Cleanliness Should Not Be Overlooked GREASES Rich Wurzbach | MRG Labs "Many of the tools that work for oil, such as filtration and moisture removal technologies, aren't readily applicable to grease."