Kanban (カ ン バ ン), Literally meaning signboard or billboard, is a concept related to tight manufacturing (Lean Manufacturing) and just-in-time production (JIT).
What is Kanban methodology?
Kanban is not an inventory control system. Rather, it is a planning system that helps determine what, when, and how much to produce.
Kanban maintains material levels in storage; when a signal is sent to produce or send a new product, the material is consumed. These alerts are tracked through a depletion cycle and convey exceptional visibility to suppliers and buyers.
Origin of Kanban
In the late 1940s, Toyota began researching supermarkets and their inventory methods, based on the idea that customers were getting exactly what they wanted in their convenient time and quantity. Moreover, supermarkets do not keep large quantities in stock, as future supply is secured. Read the material about Kanban system on Toyota corporate website.
Kanban cards are a key component through which consumers signal the need to move materials in the manufacturing process (or from/to external suppliers). The card so placed is a signal that a type of material has been exhausted. Additional color can also be conveyed by the color of the card – for example, a yellow card could mean that the material is depleted sooner, and the red is missing in the necessary unit of production. Software products such as Oracle ERP, SAP ERP, or Microsoft DynamicsAX also use the Kanban concept.
Read Kanban vs Scrum on Scrum Time magazine.
The 6 Toyota Rules
- Do not send defective products to the next process
- The next process is to download only what is needed
- Only produce the exact amount that will be withdrawn from the next process
- Measure production
- Kanban is a means of improvement
- Stabilize and balance the process
Six Basic Kanban Practices
Kanban is a production management method that emphasizes on delivery just in time, without overburdening team members.
Anderson also identifies five key properties that have been observed in every successful implementation of the Kanban method. These five were later renamed in practice and increased by an additional six. Read Kanban vs. Scrum: What Are the Differences on the EduWiki.me website.
The intellectual work process is inherently invisible. Visualizing the workflow is key to understanding how work goes. Without understanding the workflow, making the right changes is more difficult. A known method for visualizing the workflow is to use a wall with columns and maps. The columns represent the different states or steps of the workflow.
Limit work-in-progress tasks
Restricting tasks that are “in progress” states that a system for taking over (“towing”) tasks that affect parts of the work process or the entire work process must be implemented. This system will act as one of the main incentives for continuous, gradual changes to the system. The system can be implemented as a kanban system, CONWIP system, DBR system or another variant. The critical elements are that ongoing work in each stage of the workflow is limited and new tasks are “downloaded” when capacity is available in the resource until the limit for work in progress is reached.
The work process at each stage should be monitored, measured and reported. By actively managing the process, it can be assessed whether continuous, gradual changes to the system will have positive or negative effects.
While the mechanism of a process is not strictly explained, it may often be impossible to discuss its improvement. Without a clear understanding of how things work and how the work should be done, any discussion can be emotional and subjective. When there is a correct and accurate understanding, it is possible to move to a more rational, empirical and objective discussion of the problems. This makes consensus on proposals for improvement more likely.
Organizations that did not introduce the second level of feedback, evaluation of operations, generally did not witness improvements beyond the local team level.
Develop collaboratively, evolve experimentally (using models and scientific methods)
The Kanban method encourages the small, long-lasting and evolutionary changes that remain. When teams share an equal understanding of work theories, workflows, and risks, they are more likely to build shared understandings of a problem and offer improvement actions to which they agree. The method proposes the use of a scientific approach for the introduction of continuous, gradual and evolutionary changes. The method does not specify the specific scientific approach to be used.
The main models used are:
- Theory of constraints (studying bottlenecks or obstacles)
- Lean model (based on the concept of “wasting”)