How Do I Find the Bottleneck in My Plant?
To perform a bottleneck analysis, you must first identify the bottleneck(s) in your plant. Finding the bottleneck in the plant depends on what you have available. If you have data from Mingo, you can use the data to help you find the bottleneck by notifying you of when you have one and when it’s bad.
If you have a production line, you can use, in our system at least, the Pareto Charts to determine where your bottlenecks actually are by looking at excess downtime. Which machines or stations on this line have the most downtime? Which ones are running the slowest? Which ones have the biggest quality issues? When you know this information, you will find your bottlenecks.
This is probably the easiest way to do a bottleneck analysis. But, what if you don’t have a system in place like Mingo? If you don’t have data (or it’s all manual), the next best thing is to get up out of your chair and go walk the plant. Talk to people, and figure out where the bottleneck is. (Really, you should do this if you have data, too, but only after you use the Pareto Chart to determine the location.)
Getting up and walking the plant is going to show you exactly where bottlenecks are. That’s essentially your bottleneck analysis.
This method is very similar to what Alex does in the Goal. We’ve talked about this book many, many times, but if you haven’t yet read it, we highly recommend you do. (Here’s the link to buy, and no we don’t get any sort of payment for this – we’re just very passionate about efficient manufacturing.) In 1 particular chapter, there’s another bottleneck on the floor, but Alex, the main character, is unsure where it is. They’ve found the 1st bottleneck a few chapters before, but he’s confused about how another could arise so quickly. So, he gathers his team and they walk the floor. They talk to people to determine where the biggest problems are. This is how they find their bottleneck.
People working on the floor typically know where the bottleneck is. They know how product moves throughout the factory, and they know the issues associated with the plant. If you go talk to people on the floor and ask, “Where do we think the biggest bottlenecks are?”, you’ll find your bottlenecks relatively quickly. Then, you can begin focusing your efforts on fixing them.
How Do I Fix the Bottleneck?
Most of the time, if you have no data or even minimal data collection on the lines or departments, walking the plant in the same areas and talking with people on the floor will give you a better idea of what the issues are. This is basically a manual bottleneck analysis. You’re asking questions about and looking for:
• Are changeovers taking too long?
• Do we have excess downtime?
• Are we running slow?
• Do we have a lot of rework?
• Do we have quality issues?
• Do we have staffing problems?
• Are we waiting on the material?
• Are we blocked because downstream operations are having issues?
• Is it a maintenance problem?
Let’s take downtime for example. There’s a lot of different things that can cause downtime. If excess downtime is in fact causing a significant bottleneck, what you want to do is analyze and focus on the biggest downtime events using the Pareto principle and the Pareto Chart.
Typically, these things follow the 80/20 rule. 80% of your downtime follows this handful of reasons or 80% of your bottleneck reasons are going to come from this handful of reasons. Once you’re able to track that 80% of the reasons, you can begin to correct the problems.
You need to start working on those and chipping away at them.
Matt Hill, Operations Improvement Coordinator at H&T, the world’s largest battery component manufacturer describes exactly what we’re talking about in the video below. They had significant issues with downtime and once they were able to make improvements, Matt and his team moved on to improve cycle times, chipping away at one problem at a time.
Usually, there are a lot of easy things to solve once you start looking at data on these machines, even if you’re collecting it manually. You can solve these problems pretty quickly and that, alone, will allow you to remove a lot of waste and issues causing the bottleneck.
If that does not eliminate your bottleneck or get it to the point where you want it, then you keep following the same process of performing a bottleneck analysis – tackling the biggest issues one by one. If you need more data, collect more data. If you need better data, figure out how to get higher quality data. Things like Mingo can help with that because it will be more consistent.
And, then keep working that 80/20 rule. Once you knock down that first huge downtime, what’s the next one? Then the next? And, you just keep going. Maybe you move on from downtime and you’re now looking at rework. Or, maybe it’s staffing. Whatever the problem, you just keep working to fix the problems and improve.
We have customers who find that 1 in 4 products or 25% of their products has to be reworked. This is a huge problem. It’s a lot of wasted time and effort. But, by collecting data and determining where the biggest problems are, they’re able to take steps to reduce the amount of rework, inevitably eliminating, or reducing, the bottleneck.
The other important thing to think about is that, while trying to focus on fixing the bottlenecks, you should look at things holistically as well. Again, this goes back to a topic discussed during The Goal. (Seriously, go read it right now!) At some point, you may improve your bottleneck to the point where another bottleneck may appear. And, then what do you do?
This brings us to our next point, holistically looking at your plant is just as important, if not more important, than looking at each bottleneck as its own problem. It may be an interesting take on a bottleneck analysis, but we firmly believe in this thinking.
How To Do a Bottleneck Analysis According to the Experts
“What we know now,” Alex tells Jonah in The Goal, “is that we shouldn’t be looking at each local area and trying to trim it. We should be trying to optimize the whole system.”
In this book, Alex and his team find and correct their bottleneck, but as their plight continues, another bottleneck appears. For Alex, this is confusing. How does another bottleneck arise when everything has been optimized? They did a bottleneck analysis and solved the problem, but surprisingly, they’ve found another problem. But, that’s the catch. Instead of looking at the plant holistically, they were simply looking at each individual line as its own entity.
“A bottleneck,” Jonah continues, “is any resource whose capacity is equal to or less than the demand placed upon it. A non-bottleneck is any resource whose capacity is greater than the demand placed on it.”
Sounds simple, right? When you begin to improve the plant, one line at a time, while looking holistically at how the plant operates, you’re seeing all of the potential problems. It all comes down to the idea of “Balance flow, not capacity,” as Jonah reiterates.
“Speaking fundamentally, the bottleneck flow should be on par with demand,” Jonah explains.
It’s a point that is so crucial to manufacturing, and one that is also reiterated in The Toyota Way. (We’re also huge fans of this book – here’s the link to the newest edition if you haven’t yet read it.)
Generally, when you’re attempting to create balanced, continuous flow (as illustrated in the example from The Goal by looking at the plant holistically), you’re building in quality, creating flexibility, creating higher productivity, freeing up floor space, improving safety, improving morale, and reducing the cost of inventory.
It may sound like a lot, but a continuous flow, and keeping in mind bottlenecks, will bring problems to the surface. The Toyota Way lays out one of the key principles, “Create flow to move material and information fast as well as to link processes and people together so that problems surface right away.”
“Bottlenecks are not necessarily bad – or good,” says Jonah, “they are simply a reality. What I am suggesting is that where they exist, you must then use them to control the flow through the system and into the market. “