by GayEllen Stulp, Department Head, Eli Lilly-Lafayette
Eli Lilly’s Lafayette facility was having significant problems with their centrifuge equipment, which processes liquid streams in purification. There were an average of two belt failures and one seal failure every week, along with vibration levels on some of the machines exceeding two inches/second. These failures were costing 8 to 10 hours a week in down time and $183,000 a year in maintenance expense. The action team assembled to work on these issues had representatives from operations, maintenance and engineering.
The team conducted a root cause failure analysis and determined that the real villains were a lack of proper cleaning and a number of issues directly related to the condition of the equipment, such as poor shaft to rotor alignment, out of tolerance bearing fit, poor condition of o-ring seating surfaces and unmatched belt sets. To really eliminate these defects (in operator technique and equipment failure), every person on the team needed to contribute from their area of expertise as well as calling in experts from outside the company.
The countermeasures that the team recommended and instituted were:
- Improve cleaning. They obtained a high pressure system so the centrifuges could really be cleaned and worked on during the CIP procedure.
- Refurbish centrifuges. They refurbished the centrifuges and brought them into spec on all the tolerances. They obtained a quote of $55,000 from the manufacturer for refurbishing each pod. By working with a local machine shop, they were able to negotiate a price of $20,000 and a delivery time that was two months less than offered by the manufacturer. They saved a total of $150,000 on the cost of the rebuilds.
- Install test stand. They installed a test stand to balance the centrifuges when they returned from rebuilding and/or when troubleshooting was needed. A procedure for alignment and routine vibration analysis was also developed.
The results have been TREMENDOUS! The belt failures now occur less than once every three months, rather than twice a week. The seal failures now occur less than once a month rather than once a week. Vibration levels have been reduced ten fold or more. The benefits to the business are equally impressive. The maintenance expenses have been reduced by $150,000 a year because of the reduction in repairs. The additional up-time has added production throughput and $5,000,000 to the bottom line for the company.
Get the right people in the room and look out! The centrifuge team proves once again that Lilly people can pull together and really accomplish great things. Together Everyone Accomplishes More is their slogan and proactive maintenance’s goal is to accomplish more with the people and equipment they have on site.