A large industrial supply company wanted a content venue to talk about multiple topics, including MRO, supply chain, factory best practices, and more. Along with Traffic-prm, I came up with the central idea of resilient manufacturing: manufacturing best practices that were not just lean or green, but also best able to avoid disasters, maintenance issues, and other things that cause downtime. The blog halted early in its life, but I still like the posts we did.
Here’s one that I particularly liked:
Smart Maintenance, Not Less: Or, How Everyone Gets Waddington Wrong
In Maintenance circles, many folks talk about the Waddington Effect. This is the finding that regular maintenance often causes more problems than it fixes. And so people assume that doing regular maintenance less often (or not at all) will actually decrease problems, resulting in fewer production halts.
But nothing could be further from the truth. In fact, Waddington showed that maintenance needs to be done better.
The effect gets its name from one Conrad Waddington, a consult for the British Royal Air Force during WWII. Waddington noticed that, at any given time, a full quarter of the RAF’s bombers were having maintenance done instead of doing their main job (finding and bombing German U-boats). So Waddington began collecting and analyzing the logs of the planes to see if he could predict when unscheduled maintenance was most likely to occur.
What he discovered was surprising. He found that a plane was almost twice as likely to come in for unscheduled maintenance soon after having scheduled maintenance. Think: if parts tended to wear out at random times, planes should come in for maintenance at a steady rate, irrespective of when maintenance occurred. Waddington’s data only made sense if the scheduled maintenance itself was doing more harm than good.
Waddington proposed two reasons for this. First, regular maintenance often involved replacing parts that were likely to wear out—whether or not the part was actually worn. But the chances of getting a defective part from the factory were greater than the chances that a working part would suddenly wear out. So many parts in perfectly good working order were being replaced with factory defective parts.
The second reason was sheer human error. Every maintenance cycle introduced the possibility that someone would make a mistake: forget a component, strip a screw, install a part incorrectly, etc. Again, maintenance often appeared to do more harm than good.
The Waddington Effect is very real. The problem is that most people take its existence to mean that regular preventative maintenance should be skipped in favor of reactive maintenance (or at least longer periods between regular maintenance operations.)
But this is wrong and reactionary. The Waddington Effect shouldn’t mean less maintenance. It means smarter maintenance. Here’s how to approach Smart Maintenance in the light of Waddington:
- Sure, blindly replacing parts, regardless of their condition, is wasteful. Regular maintenance should start by using the senses. Does the part look worn? Is it rattling or making noise? Regular maintenance should first be about looking for potential issues, not swapping parts.
- Factory defective parts are always a possibility. But the problem here is not maintenance. It’s stocking defective parts in the first place. This is where supplier relationships—and trust—are so critical. You should find a supplier that you trust to provide the minimum of defective parts. And even then, it doesn’t hurt to test your parts (or have your supplier test them) before they are needed.
- Maintenance issues tend to arise not because of improper training, but because someone is trying to cut corners: improperly storing parts, ordering a cheaper substitute part, rushing a repair due to disorganization, etc. In short, maintenance personnel can’t simply “phone it in.” You should help the people doing the actual maintenance stay organized and take pride in their work. If they can find exactly the part they need (and, for that matter, the tools they need to install that part) quickly and easily, and perform the maintenance thoroughly, human errors will decrease exponentially.