Remember the training montages in the Rocky movies? The ones where he's pulling himself up from a devastating failure, laser-focused on redemption? When you track Mean Time To Repair, it's the same, minus all the emotional drama and awesome music.
About halfway through Rocky VI, Rocky explains the role of failure in life. He's putting into words the philosophy that drives all the earlier movies.
Let's break this down into ideas we can use to understand MTTR, a key failure metric.
“Let me tell you something you already know. The world ain't all sunshine and rainbows. It's a very mean and nasty place, and I don't care how tough you are, it will beat you to your knees and keep you there permanently if you let it. You, me, or nobody is gonna hit as hard as life. But it ain't about how hard you hit. It's about how hard you can get hit and keep moving forward; how much you can take and keep moving forward. That's how winning is done! ... But until you start believing in yourself, you ain't gonna have a life.”
Failure: a working definition
"It's a very mean and nasty place and I don't care how tough you are it will beat you to your knees and keep you there permanently if you let it."
That's a dark view of the world, but he's not wrong. The main idea here is that we have to expect things to fail, and if we let it, failure can not only push us down but also keep us there.
But what do we mean by "failure"? For Rocky, it's losing a fight. For us, it's when an asset stops producing the desired result at the desired rate. Here's another important difference between us and Rocky: He can only win or lose, there's nothing in between, but we can have total or partial failures. A total failure is when an asset stops working altogether. With a partial failure, the asset might run at the wrong speed or spit out defective products. It's still a failure.
Now that we know what failure is and that it's a part of life, let's look at what Rocky says about how to deal with it.
MTTR: Mean Time To Repair
"You, me, or nobody is gonna hit as hard as life. But it ain't about how hard you hit. It's about how hard you can get hit and keep moving forward; how much you can take and keep moving forward. That's how winning is done!"
Rocky knows that failure is inevitable, both inside and outside the ring. What defines us, then, is what we do next. Life is about how good you are at getting back up again. With Mean Time To Repair, we're measuring how efficiently the maintenance department gets assets back up and running.
The first thing you need to know is how much time was spent repairing an asset over a set period. Say you have a press with a tricky motor. Over a week, you spend a total of four hours working on it. The first time you work on it for an hour and a half. Then the second time you need another two and a half hours. Something to remember: In this specific case, the lengths of time to repair the asset are fairly similar. This does not have to be the case. You can still use MTTR with very different repair times. So, on another asset, the first time you fixed it, you needed thirty minutes. The second time, three hours. Third time, two days.
It's fine if the lengths of time are very different from one another. But, the people doing the repairs need to be roughly the same in terms of ability and preparation. What you want to know is how long a properly trained professional using a clear set of instructions takes to complete the repairs. If some of the data you're collecting is from a new hire working on an asset without an O&M manual, you're not going to end up with a useful result.
Next, take the total amount of time (which we already said was four hours) and divide it by the number of times you worked on the asset (which we said was two). Your MTTR is 2.
Generally, you want this number to be as small as possible, so once you have it, you can start to look for concrete steps to shrink it.
For example, you might start to think about staffing. Maybe you need more people overall or just more people with specific skill sets. Additional training for current staff might be an option. MTTR is also often used to evaluate which spare parts to keep onsite and to set par levels. If things are taking too long to repair, it could be because tracking down the required parts is taking too much time and effort.
MTTR can even be helpful when deciding to repair or replace an asset. Over the useful life of an asset, the MTTR will trend up. Older assets take more time to repair because their failures tend to be more serious. By looking at the changes to its MTTR over time, the front office can better decide when an asset needs to be replaced or if it makes more sense to keep asking the maintenance department to repair it.
The front office can also use MTTR to make better decisions about which new assets to buy. One growing trend for assets is modular design. Imagine you have to fix one tiny spring in an old wristwatch. Just think of how carefully you would need to take the watch apart, replace that one broken piece, and then put everything back together. It's a nightmare. But if that same watch had a more modular design, when you opened it up, there would be only three "pieces." Inside each piece would be all the same little screws, springs, and whatnots you'd find in a regular watch, but here they'd be housed in easily removed and replaced compartments. When the front office has its eye on MTTR, it's more likely to buy modular assets that are easier to repair, which directly benefits the maintenance department.
MTTR is not always MTTR
It can get a bit confusing. People use the same acronym for two closely related but different metrics.
Mean Time To Repair uses the amount of time it takes a competent technician with good instructions to complete a repair. So, it's from when they start to when they finish, including the time they take to fix the problem, test their work, and then get the asset running again. Mean Time To Recover includes all the above plus the time it took to notify the maintenance department and have them diagnose the problem.
Using the terms interchangeably can lead to costly misunderstandings. When looking at service agreements, for example, make sure everyone agrees on which metric is being referenced. You'll also want to make sure your department is held accountable to the metric that's fair in your specific situation. If operators are still slow to report failures even after you've gone out of your way to make it easy for them, Mean Time To Recover paints an unfair picture of your department's performance.
"But until you start believing in yourself, you ain't gonna have a life."
Here Rocky highlights the importance of trusting in your own value and chances for success. It's an incredibly moving moment in the scene and carries a powerful message. It's also a bit over the top for a discussion of a failure metric. Or maybe not. There is a bit of a leap of faith at the start when you're collecting the data you'll eventually use to calculate the MTTR. You have to trust that it's going to be worth the time and effort.
Speaking of value, you’ll need to ensure the value of the data you collect. You’ll need accurate numbers for the following:
- Hours of maintenance labor
- Number of breakdowns
- Operational time
For that last one, take the expected operating hours and subtract the total equipment downtime.
You can try to collect all this data using paper and pen or spreadsheets, but it's going to be tedious. And when people are bored, they tend to make little mistakes, which in this situation then snowball into bigger ones. Writing down or copy and pasting the wrong number even just a few times will throw off the final MTTR by a wide margin. You're much better off using a CMMS that lets you track work orders and inventory, which makes pulling out the numbers you need that much easier.
Tracking new metrics takes time and effort, but there are tangible rewards. If you feel like MTTR would benefit your department, but need some inspiration to get the ball rolling, here are all Rocky's training montages in one video. Once you’ve finished watching the video, make sure to come back and read more of the blog.