What Are Different Types of Kanban
As Kanban is not a fixed methodology that has an ownership like Six Sigma, it can actually mean a few different things, and can be implemented in a number of different ways. On top of this, the term can be used in a number of different contexts, so it could mean different things to different people.
Where Does It Come from?
The idea behind Kanban was first developed in the 1940’s by Toyota. As they were looking for an efficient way to exercise logistical control, and to maintain efficient inventory levels, they turned their attention to American supermarkets. Their observations showed that in a supermarket, customers retrieve what they need from the shelves. As stock levels go down, this triggers the supermarket personnel to restock them. Toyota saw this as efficient for restocking parts, and decided to implement it on the factory floor.
In their implementation, each process was viewed as a customer to the prior process, so required components would be stocked or built only as they are needed and used. This meant that production could actually be regulated by demand as signals would pass through their production chain. The goal is to supply “what is needed, when it is needed, and in the amount needed“
The main innovation in their approach was to make all of this visual. The Japanese word ‘kanban’ actually means signal or card, and this is what the original idea was based on. In order for this pull system to work, it required a way for signals to be passed. Toyota landed on was visual cards that had all the needed information on them.
Types of Kanban Based on the Usage
Toyota’s Kanban approach continued to develop, and as it was implemented in different environments. Its evolution branched into a few different types of Kanban, despite the fact that the differences are often a bit fluid. Still, exploring them can help us understand what Kanban has to offer as a whole.
This type of Kanban is what Toyota actually developed first. This is a system utilizing visual Kanban signals to trigger action. In this type of Kanban there are two types of Kanbans or Kanban Cards:
- Production Kanban which authorizes the workstation to produce a fixed amount of unit
- Transportation Kanban authorizes the transportation of a particular container to a downstream workstation.
The implementation of these cards creates a Kanban system that regulates itself, where items are not centralized. Each workstation or worker interacts with the cards they receive, which triggers them into action. There are variations on it with Kanban Bins, Card Holders or Racks, but they all iterate on the same basic mechanics that were inspired by the way supermarket restocks were triggered by customer demand.
While Kanban Systems have Kanban Cards physically flow through the organization, there is another type of Kanban that has them posted in a central location. While it’s inspired by the Kanban logistic control systems used on factory floors, Kanban Boards put the Kanban Cards at a central location. This is an implementation of the Kanban principles that has distinctly different application and benefits.
A Kanban Board is actually a workflow visualization and management tool. It makes the tasks that a team or organization need to handle stand out in a visual way, that is accessible to everybody. This makes this approach much more flexible, and allows it to be useful in a much wider variety of applications and environments. The Kanban Board is separated in columns, which represent the discrete steps in a process a particular tasks needs to go through, in order to transform its status from impending to complete. Sticky notes are added to represent each task, and the team reviews the status of each action to determine how to move it to the next phase. That may require the task to be reassigned to someone else, or for leadership to get involved to help it move forward. The function of the Kanban implementation is to allow a team to prioritize, organize, and optimize their own workflow, while facilitating communication by providing clear visual information for all tasks.
Because of their flexibility, Kanban Boards have been implemented across many different industries, and can even be used by individuals to keep organized.