Kanban in general

The production process is controlled with the help of kanban cards. A kanban card stands for an internal and an external task. The aim of the method is the optimal controlling of the material flow and production adjusted to the actual requirements. In this connection consumption, acquisition period and amount play an important role. The additional delivery follows before well-defined criteria – through kanban cards (pull-principle).

This method makes a continual improvement possible.

Overview:

This method was originally aimed at the mass production on an assembly line (Taiichi Ohno, Toyota Motor Corporation 1949).
It implements the pull-principle (empowerment – self-organized teams).
The aim is increasing the productivity.
Production resources are only made available if absolutely necessary, advance planning and storage are minimized (=dynamic process orientation, transparency, lean and agile).
Even distribution of the load among all persons involved, as a result limitation of the activities running in parallel (Kanban WiP Limits, WiP = Work in Progress).
Team members are supposed to have as broad a view as possible of the processes and products.
The focus lies on the learning of the organization (Kaizen).

Rules of this method:

Conditions for an optimal use are an as small as possible range of variation in demand, a quantitative high consumption and a manageable variety of products.

The following factors can be determined for the necessary material/parts:

What quantities are
- where and
- when required?

The process oriented towards the customer needs

only as much material (parts) as required and
- at the right time (not prematurely).

The process oriented towards the supplier

does not produce for stock and
- supplies the correct material for the customer process.

The kanban coordinator provides

a steady utilization of all production processes and
- the right number of kanban cards (every kanban card indirectly produces storage and transport costs).

Disadvantages

Originally Kanban is a system oriented towards the serial production of items like cars or industrial goods. The applied mechanisms are interesting, but not really adaptable for other systems. The insights gained from the system developed by Toyota can also be used for other methods.