Do you need your rotating equipment dynamically balanced?
During my 48 years in the rotating equipment service industry throughout Maine and New England, I have received thousands of telephone calls only after equipment had failed or was on the verge of failure. A high percentage of those calls were centered on the subject of equipment vibration or excessive equipment vibration. When receiving a call from a customer who said, “my equipment, fan, motor, pump or generator is out of balance” my very first response was “what happened?” A piece of rotating equipment doesn’t all of a sudden become “out of balance”. For equipment already in service, vibration levels may elevate gradually over time as contamination builds up on the rotating element, as an abrasive action wears the rotating element, as a bearing fit on the shaft wears, as a sheave wears, or even as the rotating element begins to self destruct.
If in fact there is excessive vibration, in most cases some type of repairs or cleaning should be completed before an on-site trim balancing is completed. Unless repairs and cleaning is completed before the trim balancing, vibration levels will continue to elevate again after balancing has been completed. The root cause of the excessive vibration must be addressed in order to have a trim balancing of the rotating element be effective over the long term.
With that being said, what about the customer that calls and suggests his newly installed equipment has excessive vibration levels and needs to be balanced? In this case excessive vibration may just be a result of inadequate balancing at the factory. My experience with these types of issues are most generally one of two scenarios; either too much weight was added to the rotating element during the factory balancing or not enough weight was added to the element during factory balancing. When called to do that type of balancing project, the trim balancing weights I install quite often end up either next to the factory installed weights (the factory didn’t install enough weight) or 180 degrees away from the factory installed weights (the factory added too much weight during their balancing process).
Hope this helps you evaluate your very first encounter with excessive vibration issues with your equipment. We’ll present some unique case studies moving forward.
