The customer takt represents the demand of your customers for your your products. The line takt represents the ability of your production system to produce. Hence, the customer takt should meet the line takt. This series of blog posts looks into what to do if they do NOT match. In my previous post I talked about small fluctuations… which are pretty much no problem in the short term, as inventory (for make-to-stock) or lead time and utilization (for make-to-order) will handle these. However, if the fluctuations trend in one or another direction, eventually you have to act. In this post I will talk more about what to do if the customer takt is faster than your line takt (i.e., the customer demand exceeds your current capacity).
Fluctuation
(EN) What If Your Customer Takt and Your System Takt Do Not Match—Small Fluctuations
One of the key parameters for setting up and running any production system is the customer takt (i.e., the customer demand). This is measured as the average time between the demand of a customer for one product, based on the available working time. In the grand picture, the customer takt (the customer demand) should match the line takt (the production speed of the line). But what should you do if it doesn’t? Let’s investigate this in a small series of posts. This first post looks at small fluctuations.
(EN) On the Value of Time in Manufacturing—Fluctuations
In my last post, I talked about the value of time in manufacturing, focusing on cyclic or repeatable times. However, the bigger problems are often non-cyclic or fluctuating times. The main difference is that non-cyclic work is a fluctuation, and it causes all kinds of other waste, from excess inventory to additional waiting times. On the other hand, depending on how often the fluctuation happens, there may not be so much benefit in reducing its duration. Read on…
(EN) Fluctuations on Continuously Moving Assembly Lines 3—The Value of Team Leaders
In my last two posts I described the impact of fluctuations on the duration of the work on a continuously moving assembly line. One key tool for reducing fluctuations on Toyota assembly lines is the team leader, the frontline support for operators. Team leaders reduce fluctuations in general by taking over irregular tasks like delivering material, taking away trash, and explaining situations to a manager. They also reduce especially long fluctuations by supporting the operators in their own work if there are problems, thus reducing stops of the line. This post will look in more detail at the beneficial effects of team leaders on a moving assembly line.
(EN) Fluctuations on Continuously Moving Assembly Lines 2—Waiting Times
In my previous post I posed the problem of decoupling fluctuations on continuously moving assembly lines. You cannot decouple using inventory; you can decouple only long-term fluctuations using capacity, while all other fluctuations are decoupled using time. In my last post I introduced the topic and urged you not to have workers between different stations to handle fluctuations. In this post I will look in more detail at the waiting time of the workers due to fluctuations in the work duration for the stations.
(EN) Fluctuations on Continuously Moving Assembly Lines 1—Don’t Move the Workers Around!
A lot of industries use continuously moving assembly lines. This is common in automotive, but also in many others. The challenge is to manage the fluctuations. You cannot decouple using inventory; you can decouple only long-term fluctuations using capacity, while all other fluctuations are decoupled using time. This is the first blog post of a series digging deeper into how to handle or NOT handle fluctuations on continuously moving assembly lines. This first post looks at the effect when workers move among different stations.
(EN) The Benefit for Denso of Reducing Fluctuations
I have written a lot about leveling and the value of fluctuation in previous blog posts. In this post I will show quantitatively what the benefit of reduced fluctuations is for Denso, part of the Toyota group and a supplier to many other car makers too.
(EN) On Leveling and Fluctuations—How Does Toyota Do Leveling?
My last two posts in this three-post series on leveling talked about fluctuations and leveling in general, and the challenges and costs associated with leveling. In this last post I will go into greater detail on how Toyota does its leveling. Because Toyota does this actually quite well.