The bottleneck walk is far and wide my most favorite method to detect bottlenecks on the shop floor (not only because it was developed by me, but also because it is really good!). You can detect shifting bottlenecks, using no math whatsoever and no time measurements, simply by walking along the production line and observing the line. It’s almost too easy to believe, but it works like a charm! Due to the length of this topic, I have broken the article into two posts. This first post details how to find the current temporary bottleneck. The second post details how to determine the big picture regarding the bottlenecks. See below for a complete list of posts on this series on bottlenecks.
This post describes a second accurate way to detect the bottleneck in manufacturing systems, based on the precise times a process is waiting or active. The method is highly accurate, not only giving the likelihoods of different processes being the (temporary) bottleneck, but also estimating the improvement of the entire system capacity if the bottleneck(s) are improved. It is also possible to observe the shifting of these bottlenecks over time. The method was developed by me during my time at the Toyota Central R&D Laboratories in Japan. See below for a complete list of posts on this series on bottlenecks.
To improve your system capacity, it is a must to find and improve your bottleneck. However, finding the bottleneck is difficult. Most methods used in industry fail at finding the bottleneck. As discussed in my previous post on Shifting Bottlenecks, this is mostly due to bottlenecks being dynamic and frequently shifting from one process to the next. In this post we will look at common bottleneck detection methods used in industry. More importantly, we will find out more about failures of bottleneck detection methods commonly used in industry. Subsequent posts look at bottleneck detection methods that actually DO work!
Improving system capacity requires you to find the bottleneck; however, bottleneck detection is a tricky business. The main problem is that most bottlenecks are not static, but move around. In this post we will look at the behavior of bottlenecks on the shop floor. This is the first post in a series of posts on bottleneck detection. Subsequent posts will look at the flaws of commonly used methods to find the bottleneck and describe two new reliable methods for finding the bottleneck on the shop floor.
One of the main aspects of lean manufacturing is quality. This post discusses the differing attitudes regarding quality in different corporate cultures. In particular, the Toyota brake recalls and the GM ignition recalls are compared.
Toyota has developed what is probably the finest production system in the world, the Toyota Production System. There is general consensus in the rest of the world that its methods and philosophies can significantly improve efficiency and quality, to the point that anything Toyota does is admired and copied. Some practitioners seem to wear rose-colored glasses when talking about Toyota. However, like any company, Toyota does have its fair share of problems and mishaps to deal with, from the 1950 near collapse, to the US gas pedal recalls during 2009–2011. This post will discuss the employee relationship crisis at Toyota around 1990 and Toyota’s countermeasures.
In my previous two posts, I described how to calculate the number of kanbans (Post 1 and Post 2). However, this calculation is complex, and the result is nothing more than a very rough estimate. Hence my preferred method for determining the number of kanbans is, broadly speaking, “just take enough, and then see if you can reduce them.” In this post, I would like to explain this approach and also discuss how and when to update the number of kanbans.
This is the second post on kanban calculation (if possible, please read the first post on kanban calculation first). There are two possible approaches. First, you can calculate the number of kanbans using a kanban formula (due to its length, split into a first post and this second post). Alternatively, you can estimate the number of kanbans and adjust the system as it is running (as shown in a third post).