Centrifugal Pump Cooling and Lubricant Application— a “best Technology” Update

Process pumps experience widely different operating times to failure. U.S. refineries achieve pump mean-times-between-failure (MTBFs) ranging from less than three years to in excess of eight years. While the importance of pump hydraulic design seems well understood, insufficient attention has been given to important issues of bearing lubricant selection, protection of the oil against contaminant ingress, and optimized application of the lubricant. Bearing cooling issues are addressed and both feasibility and potential monetary value of lube-related energy conservation on pumps with static oil sumps are authoritatively documented. However, while this presentation may not be good news to everybody, it highlights only those concepts that are well-proven and understood by best-of-class performers. As such, these issues merit serious consideration and follow-up by plants that are trying to catch up.