Kanban

Kanban was developed at Toyota by Taiichi Ohno. He was looking for an efficient system that made it possible to achieve a high level of production. Kanban is a visual Lean Tool and is often applied in combination with JIT (Just-In-Time). Components are only produced when there is a request for it. Kanban comes from the Japanese words ‘kan’, which means ‘visual’, and ‘ban’ meaning ‘card or board’. Through simple signal cards (now also digital), they ensure that a signal is given when something is needed. For example, the ordering of certain products.

KANBAN AS A PRODUCTION SYSTEM

Kanban supports production system management as a whole. Kanban is an excellent way to start improvements. Problem areas and issues emerge once the number of Kanban cards in circulation decreases. This actually also means that the amount of work in process is reduced.

A TRANSPARENT PRODUCTION PROCESS WITH KANBAN

Kanban can be moulded into various shapes. One of those is the Kanban board. This is a variation on the Kanban cards. You can make a board with sticky notes, magnets and cards, in order to get an overview of the amount of work and tasks. Each card stands for a product in the production process and the movement on the board shows the production process. The board is often divided into three columns: “waiting for production”, “production” and “produced”.

Another form of Kanban is the Two-Bin System, also called the ‘two-tray system’. The first bin contains the work stock used for production. The second bin contains the reserve stock. Once the first bin is empty, the Kanban is removed from the bin and used as a signal to restock. The second bin now moves forward. When it has been restocked, the system is in balance again. Once the second bin is empty, it starts to restock again by using the Kanban card, which is always in the bin.

There are different types of Kanban:

• Transportation kanban: a signal to the previous stage that materials can be taken out of stock and transported to the next point. These kanbans contain information such as: ID, where it’s coming from, where it’s going.
• Production kanban: a signal to the production that they can start producing. It contains information about operations, the necessary materials, ID and/or location of where the manufactured product needs to go.
• Sales kanban: is similar to the Transport kanban, but used by the external suppliers.
• Signal kanban: consists of the signal production kanban and the signal material kanban.

STOCK LEVEL CALCULATION – KANBAN:

There are many methodologies to calculate what the correct stock level is. To make a calculation on the optimal stock, some data is required. The actual demand/use for the corresponding (end) product and the variation in demand/consumption (does it display many fluctuations or just a few?)If these factors are taken into account in the determination of the optimal stock level, then Kanban can be implemented.