Even "Easy" Pumping Applications Need Attention
When I think of an easy application I recall a pump at Champion Paper that ran 17 years until the mechanical seal leaked.
By Robert L. Matthews
When I think of an easy application I recall a pump at Champion Paper that ran 17 years until the mechanical seal leaked. The rebuild showed a small amount of impeller wear, no bearing problems, and an overall rotating machine that could be resealed and run a long while again.
The seal leak was from weak spring tension allowing the faces to chatter and finally crack. The application was a chill water pump running at its BEP in a clean area that was basically forgotten about. That pump was an exception at that plant. The norm was about a one-year pump life or MTBF (mean time between failures) until steps to improve reliability were introduced. It was exciting to see the plant’s pump performance reach a 2 year MTBF and later 5 year plus.
Most plants don’t have the opportunity to run constantly at the BEP (Best Efficiency Point) or, as I like to think about it, the sweet spot. The cleaner or purer the process the greater the opportunity we have to run equipment at the BEP, in many cases. This allows the equipment to run longer with the MTBF looking impressive compared to plants that have constant changing temperature, viscosity, and abrasiveness in the pumped fluid.
What is the best maintenance practice for these so-called easy application pumps?
- Run to failure
- Monthly PMs
- Annual PMs
- Electronic monitoring and analyzing (vibration analysis, ultra sound, thermal imagining, oil analysis, and others)
- Combinations of these
- CMMS (Computerized Maintenance Management Systems)
This is not always an easy decision to make by management, if they want the best method for the plant. The number one thing to have in the plant is good record keeping; equipment history allows you the opportunity to make educated decisions that are best for the company. Always have a well trained maintenance staff to work on the equipment and have training at least once a year that increases skill levels and benefits the work site. Front line managers in these plants need more managerial skills as well as a process and equipment understanding to be the best at asset management. The CMMS is without a doubt essential for all plants, whether they be easy or tough ones to run.
Don’t cut back on maintenance man hours, justify them. The smooth running plants can get caught up in cutting cost that seems like savings at the time and over a time span can cost more, so look at total cost of ownership.
If purchasing isn’t tied in with the CMMS and working with long term savings and energy savings in your pump program, you are leaving a lot of low hanging fruit on the money tree. We need the best in, for, and from maintenance to get the best from our pumps. Set your standards high and let maintenance and operations know what they are. Without goals you will never get gold.
Remember some things that can plague our “easy to run” systems are the same as those that plague the hard to run processes. Age is often not thought about in the equipment support systems to our pumps, and we look at the pump age. Does your plant have scheduled checks on pipe hangers that support the attached pump piping, and if not why? Supports are one of the biggest problems we find.
Schedule support maintenance and inspections in the field for pumps and their attachments but don’t forget to inspect the replacement pumps, pump parts, spare motors, and so on that are ageing in the store rooms. Think of what can happen and plan around the possibilities. This is important to all plants, even those that have the easy applications like clean and pure pumped products.
About the Author: Reliability manager for Houston-based Royal Purple Ltd., Bob Matthews has 35+ years of pump industry experience — including hands-on supervision, in-plant maintenance management, consulting and training. He has taught advanced pump classes for Fortune 500 companies, universities, the Vibration Institute, ASME and FSA. Contact: www.royalpurple.com