Written by Lawrence Bouvier, CMRP, Vice President – Fuss & O’Neill Manufacturing Solutions
Is equipment downtime holding you back from achieving Lean Manufacturing success?
We all have heard of the seven wastes addressed in Lean Manufacturing, but did you ever consider that if you applied similar principles to equipment health, you’d want a discipline to create Lean Maintenance?
Overproduction, Inventory and Waiting are three of the seven lean wastes that can come as a result of equipment failures. A good maintenance process will keep these to minimum levels. So, how can we achieve this? The only way is to minimize the amount of maintenance and repair that we perform on machines!
Lean maintenance techniques achieve maximum uptime by minimizing the downtime required to perform equipment care tasks. Some of these time wasters are:
• Performing PMs too frequently
• Waiting and searching for parts, consumables or tools
• Lack of standard inspection and repair procedures
• Performing repairs incorrectly
• Performing inspections that don’t find defects
Take this anecdote as an example:
One of your maintenance technicians is given a work order to perform a PM inspection on a conveyor. Part of this is to inspect the conveyor bearings. That’s it: All it says is “Check Bearings”. The tech looks at the bearing, checks off the appropriate box on the work order and moves to the next task.
Four days later, on Friday, the conveyor screeches to a halt! The conveyor, supposedly inspected and pronounced in good condition earlier in the week, has catastrophically failed!
Another maintenance tech is called to the job and arrives an hour later – the shop has had so many breakdowns, that no techs were immediately available. This tech looks at the conveyor, but can’t figure what the problem is. Finally, after another thirty minutes, a better trained technician comes along and identifies the problem as a failed bearing. This tech goes to the tool crib to get his bearing puller to remove the bearing – but it can’t be found. After an hour of searching, it is found under a bench. It is damaged, and it takes another 30 minutes to repair it enough so that the bearing can be removed from the shaft.
Puller in hand, the tech goes to the conveyor and removes the bearing. Now, he heads to the stock room to find a replacement, but none are available!
A special order is expedited to the local supplier, who informs the technician that it will have to be shipped overnight – another 24 hours will be lost, and now production will have to work all day Saturday and Sunday, at time and a half, to make up their orders – which too, will have to be expensively expedited. The production crew is sent home after waiting for the machine to come back into service – to no avail after wasting 4 hours waiting fruitlessly. The production manager grumbles that he knew this would happen and banked inventory to cover ‘those unreliable machines’ – but didn’t have enough to cover a disaster of this magnitude – which seems to be happening more and more frequently.
The next morning, the bearing arrives and is reinstalled and production resumes. Of the 32 hours of downtime, 28 of the hours were wastes that could have been prevented!
The maintenance manager sternly decides that they are not going to run like that anymore.
The next Wednesday, the maintenance team decides upon a plan to make sure that wastes like these are completely and permanently eliminated.
Fast forward three years:
The maintenance team has implemented predictive maintenance and a good planning & scheduling program. The maintenance shop has been improved by a 5S program and every necessary supply can easily be found. Technicians are thoroughly trained in the necessary skills required to keep the plant running in top condition. The parts cribs has the part needed.
They’ve instituted a predictive maintenance program, and a technician performing a monthly inspection route hears the same bearing beginning to fail with his ultrasound probe. He reports this to the maintenance planner, who opens up a work order, orders the bearing (which doesn’t have to be kept in stock due to the ability to detect failures far in advance of its lead time to procure) and kits the parts, tools and a bearing replacement instruction in the maintenance shop.
The planner contacts production to secure a window of downtime to perform the bearing replacement. It is scheduled 3 weeks in advance, and on the day of the scheduled repair, it is achieved in less than 3 hours. The old bearing is brought back to the shop, where maintenance techs examine it and perform a root cause analysis. The team of well-trained techs establishes that this failure is the result of improper lubrication, and the planner creates a standard procedure for routine lubrication of the bearing. Confident that this will eliminate this failure mode, the planner changes the ultrasound inspection frequency from monthly to quarterly.
In this case, no unscheduled downtime was experienced – and the value added exceeded the time it took to make the repair!
The end result was that this company was able to safely produce quality parts with no interruptions to production, and avoid overtime that could have come as a result of the repair. After three years, it was becoming more the rule than the inspection that this company was gaining control of its equipment – not the other way around.
Enlightened maintenance professionals know there are tools to identify and eliminate wastes. Coaching, counseling and training employees on how to use them will help you to capitalize on this opportunity.
Some of the tools you will need to accomplish these goals are:
• Total Productive Maintenance (TPM)
• Predictive Maintenance
• Preventative Maintenance Optimization
• Reliability Centered Maintenance
• Skills Assessments & Training
• Maintenance Planning & Scheduling
• MRO Inventory Management
• Troubleshooting & Root Cause Analysis
• Maintenance Process Mapping
• Maintenance Process & Leader Standard Work
• Integration of Regulatory and Equipment Inspections
Think of your current processes, and consider the impact that a comprehensive Lean maintenance program will have on your bottom line. The application of Lean principles to your maintenance function can increase cost savings, decrease production shutdowns, and reduce employee frustration.
Contact IMEC at info@imec.org or 888.806.4632 to learn initial steps to improve your maintenance program.
