Will a real andon system bring the factory to a full stop?
Dear Gemba Coach,
What would happen if we practiced andon for real – wouldn’t the factory simply stop?
Very probably, yes. At first at least. In most companies I’ve seen that install an andon system, local management is very quickly overwhelmed by requests from the shop floor, response time lengthens, and then operators give up, and simply stop pushing the andon button or pulling the cord.
To understand this more deeply, let’s think of an electronics company that, at the time, successfully worked with andons. They didn’t start with the operator andon, but with stop-at-defect on every machine.
Visualize halls with many machines making electronic components. Each of these machines is programmed to stop if it makes 10 or so faulty components in a row. As long as it’s one bad part every so often, the machine selects out the defect and keeps running.
The CEO was really keen to improve quality, so the lean director tackled the andon issue. How could they reprogram the machines to stop at every defect? Maintenance immediately said this would be impossible – the plant would just stop.
So, in one plant, the lean director gathered the maintenance team, and told them they would, for a week, focus all their efforts on three machines, which would be reprogrammed to stop at every defect, and do nothing else than solve all the problems.
Against much griping and low expectations, this worked remarkably well. First the maintenance team solved obvious problems that had been overlooked, then more complex ones, and in the end the machines could run at their normal rhythm and still stop at every defect without needing so much attention.
They then moved on to the next batch of three machines, and so on. Eventually, they sorted the entire hall and quality improved spectacularly – as well as machine uptime.
Interestingly, the lean director found there was a learning curve to this as he repeated the same experience in the other plants of the group, and eventually, he established the stop-at-defect principle wall to wall.
The Deeper Issue
If we observe this, we can see that the difficulty with andon is not andon in itself, but the ability to respond to the problems the andons flag. The key underlying issue with andon is whether the team structure is robust enough to react to the andon. In the machine case, the lean director focused all the maintenance resources of the plant on just a few machines, which is hard to do when you move to people andon (why should some people get more attention than others?).
The deeper issue is to make sure you have the stable teams in place with team leaders who can respond to immediate questions, group leaders who are determined to be enablers of quality work on time, and access to enough maintenance engineering resources to get deeper problems fixed, including:
- Strong teams that understand andon pulls are mostly about checking standards and highlighting problems that the team itself should be able to deal with through kaizen.
- Line stops and a support structure for the deeper issues the team can’t deal with, which means having enough smart people to respond quickly.
Andon is simply the surface symptom of your will to win. If you think you’re not ready for andon, you’re just telling yourself that it’s okay not to have quick response and top quality. Let’s keep doing what we’re doing; it’s not too bad is it?
Lean is a system: just-in-time is supposed to reveal problems, but without andon these problems will remain unnoticed. Andon is not there to solve problems, but to orient the teams to learn to work better with what they’ve got, and then pick the real issues they want maintenance to work on. Maintenance can then point engineering to what really needs to be fixed, which will provide opportunities to improve both the product and the process, more specifically, the monozukuri, our art of making things. Which is what just-in-time was all about in the first place.
Yes, practicing andon for real is not easy. But what is the cost of not practicing andon? What are we telling ourselves about our commitment to quality for customers and enabling our people to do good work? The question is not whether or not you should go to andon, but how you’re going to figure out what it takes to make andon work.