Eine der Fragen für jedes Produktionssystem ist, ob das Produkt auf Lager vor dem Kundenauftrag (Lagerfertigung, make-to-stock, MTS) oder erst auf Abruf nach dem Kundenauftrag (Auftragsfertigung, make-to-order, MTO) produziert wird. In vielen Fällen ist dies eine einfache Entscheidung. Sonderanfertigungen sind immer Einzelanfertigungen, da man nicht beginnen kann, bevor man weiß, wie das Produkt aussehen wird. Für alles andere gibt es Ausnahmen. Lassen Sie mich den Entscheidungsbaum für die Entscheidung, welche Artikel auf Bestellung und welche auf Lager produziert werden sollen, näher beleuchten. Dies ist eine kurze Serie von Blogbeiträgen, und der erste befasst sich mit dem wichtigsten Aspekt (aber nicht dem einzigen) bei der Entscheidung zwischen Auftragsfertigung und Lagerfertigung
Fluctuation
(EN) Can You Plan Around Your Fluctuations?
Balancing the need of high material availability with low inventory is tricky. Pull systems are a very good way to achieve this. But sometimes people argue with me that planning can be better if you use all the available information to create a production plan which then outperforms a pull system. In theory, this could work, but in practice it rarely does. After all, that is what conventional push systems are trying to achieve, usually with mediocre results. Let’s have a look.
(EN) About Just in Time and Fluctuations (Like… a Pandemic…)
Just in Time (JIT) is a powerful tool in lean. However, it is not an easy tool. Using it without understanding the requirements can quickly make things worse. I have written about related topics before, but during the COVID-19 pandemic, Just in Time was often blamed for a lack of material, usually by people who do not understand how just in time works.
(EN) Reducing Fluctuations Downstream
This last post of my series looks at fluctuations that originate downstream from your location. In other words, how to reduce fluctuations originating from your customer. Granted, this often is the most difficult one, as you usually have not so much influence over your customers (unless you have a monopoly). Let’s have a look.
(EN) Reducing Fluctuations on Your Shop Floor
Fluctuations can also originate within your area of responsibility. In my previous post, I looked at how to reduce fluctuations coming from upstream. In this post I look at your shop floor. Using the source-make-deliver structure, this post is about reducing fluctuations at „make.“
(EN) Reducing Fluctuations Upstream
This post will list a number of tools that can help to reduce fluctuations. They can reduce fluctuations in the material flow, including its inventories and the durations and lead times. Since reducing fluctuations (mura) is an underlying important idea throughout lean manufacturing, a lot of tools can help. And, depending on how you interpret tools, this list is not even complete.
(EN) Structure for Reducing Fluctuations
This post looks at how to reduce fluctuations (mura) in manufacturing. It is a continuation of the previous post that looked at why fluctuations are so bad. Be warned, tackling fluctuations is often a tedious task that never ends, but it one of the important fundamentals for lean manufacturing. After all, the more stable a system runs, the more efficient it is. Leveling is one major method to reduce fluctuations that focuses on the production schedule. Line balancing is another one that focuses on the work content.
(EN) Why Are Fluctuations So Bad?
Fluctuations are bad for manufacturing. In lean, unevenness is one of the three evils, besides waste and overburden. In this post I will give you an introduction to fluctuations. One option to handle fluctuations is decoupling, but this addresses only the symptoms and not the cure. In my next post I will show you how to actually reduce fluctuations.