Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/468007
TO IMPROVE BY ADRIAN MESSER, UE SYSTEMS COVER STORY Keeping a handle on lubrication seems easy enough. All you need to do is to make sure the right lubri- cant is used in the right amount and at the right time. Unfortunately, it's not that simple. It has been estimated that 60 to 90 percent of all bearing failures are lubrication related. Bearing failures most often lead to unplanned downtime, which can impact production as well as affect all related components around the bearing. Downtime is costly. While the cost varies by incident and by plant, it can add up. As the most common cause of bearing failure, lubrication is serious business. For many years, this "serious business" has been conducted in a way that makes perfect sense on the surface but in fact borders on being haphazard. Many technicians have relied on preven- tive, time-based lubrication alone. That is, every "X" number of months, the grease gun comes out, and the bearings are lubricated. After all, underlubrication can be lethal, causing equipment failure, costly repairs and replacements, signifi cant unplanned down- time, and lost profi ts. But by relying solely on time-based lubrication, or even a combina- tion of planned maintenance and temperature readings to serve as a proxy for lubrication status, you run the risk of something just as bad if not worse — overlubrication. Relying on time-based, periodic lubrica- tion assumes bearings need to be greased at defi ned time periods. Often this evolves into a well-intentioned guessing game at best. Adding more lubrication to a bearing that is already adequately greased is a real risk. By using ultrasound technology (along with normal practices such as removing old grease and replacing it with new), technicians can combine standard time-based mainte- nance with condition-based predictive maintenance, gaining in the process both a clearer picture of what's really going on in their machines and improved reliability. How Ultrasound Works Ultrasonic equipment detects airborne and structure-borne ultrasounds normally inaudible to the human ear and electronically "transposes" them into audible signals, which a technician can hear through headphones and view as decibel (dB) levels on a display panel. In some instruments, the received sound can also be viewed on a spectral anal- ysis screen. With this information, a trained technician can interpret the bearing condi- tion in order to determine what, if any, corrective action is needed. 8 | January - February 2015 | www.machinerylubrication.com Using Ultrasound TO IMPROVE Lubrication P R A C T I C E S