Kanban – The Milk Example

Kanban – The Milk Example

Photo owned by devriesm (cc)

Think of something at home that you never want to be without. Recently, Paul volunteered that his family never run out of milk. How do they ensure that that happens? They keep 2 x 2 litre containers of milk in the fridge. As soon as one is empty, it is left out and prompts the next person going to the shops to collect a 2-litre container of milk. Simple? They are never without milk.

Oh, by the way, Paul’s family have never heard of kanban.

As with many lean principles, they are derived from simple common sense. A good kanban system ensures continuous supply of material. The word ‘kanban’ means ‘signal’. A kanban signal is a trigger to replenish material.

The most common type of kanban is a 2-bin kanban. 2 bins are used for each item in a storage location. Each container is filled with a quantity to cover usage over a set period of time. One ‘bin’ must be emptied before using the second. The empty bin triggers a signal.

The signal can be the bin itself, a card, a fax etc and should follow a standard process.

Bin sizes are calculated using a combination of the usage, delivery/collection frequency, supply lead time and batch size.

The target in many lean companies is to minimise bin sizes by increasing collection/delivery frequency and reducing batch sizes.

Through the application of kanban, companies can expect to reduce inventories and eliminate downtime due to material shortages.

This is one of the many tools delivered in our FETAC Lean Manufacturing Tools training course helping to minimise waste in participating companies. Click on the link for more information.