The Kanban methodology is derived from the automotive industry in Japan. It was created by Taiichi Ōno for Toyota in 1950 in order to optimize its production capacity in order to be competitive with American companies. The Kanban methodology is based on the Lean approach that is to say on the continuous improvement of production processes in order to allow production management without waste. The Lean method is based on four obvious principles:
- Reduce production costs
- Avoiding Overproduction
- Reduce time
- Produce with the best possible quality
The Kanban approach is a stock management method that allows production on demand. The main objective is to achieve a balance between production and demand.
Principles of Kanban Methodology
Unlike most companies that opt for a high-flow system that does not take into account consumer demands, the Kanban method imposes a flow-based system triggered by customer consumption. It is therefore a matter of producing a requested product, when requested and in the quantity requested.
It is therefore necessary to limit the production of a position upstream of a work chain to the exact requirements of the downstream position. The most downstream position should only be produced to meet customer demand. The Kanban system is therefore the information system that makes it possible to rapidly raise the needs of the downstream to the upstream.
The Kanban approach makes it possible to visually control the workflow. It is a matter of observing the way of working of the company in order to improve it afterwards. In addition, this flexible method allows the team to suspend the production process at any time in order to resolve a blocking problem or an emergency.
Process of Kanban Methodology
Kanban means “tag” in Japanese. The Kanban method works on a system of cards or labels, called Kanban, which correspond to a precise order from the customer. It is this command that triggers the production line. These maps continually indicate the tasks to be carried out, when to carry them out, and the tasks already performed (the available stock, for example).
The Kanban is therefore both the medium and the vehicle for the information exchanged between two workstations. This information is transmitted both by the information inscribed on the Kanban, but also by the circulation of the kanbans between the work stations. This principle makes it possible to limit the stock in progress and thus waste, especially in the event of a defect detected downstream of the production line.
It is an excellent visual tool that ensures better collaboration and communication in real time, as well as a good flow of information about the tasks to be performed. The Kanban method is based on four principles:
- Start with what you are doing now: the Kanban method uses the processes already in place and encourages an improvement in these processes.
- Accept progressive changes: employees are generally resistant to overly brutal and radical changes. The team must agree to improve the system in place through incremental changes.
- Respect the current process, roles, responsibilities and titles: To facilitate future change, the fear of change must be eliminated, including maintaining and respecting the current roles, responsibilities and professional titles of each.
- Leadership at all levels: Collaborators or senior managers, all leadership acts within the organization should be encouraged.
In the Kanban method, there are five good practices:
- Visualization: in order to understand how the devices in place work and to know the state of the project, it is essential to visualize the workflow. To do this, use an array where each column represents a step (to be done, opened, in progress, in test, finished). Each task evolves until it is completed.
- Limiting the number of tasks in progress: each step of the table can contain only a maximum number of tasks at the same time, defined according to the capacities of the team. When a task is completed, a new one can then be added.
- Flow management: It is essential to monitor measure and record the workflow through each step of the table. The aim is to know the speed and fluidity of the work.
- Clarifying Process Standards: The rules of the Kanban system must be clearly and unambiguously formulated to ensure that the team understands the work done and future improvements.
- Identifying Opportunities for Improvement: Once the team has understood the theories of work, processes and risks, it will be able to discuss a problem or a bottleneck it is facing and find improvements to be put in place.
Advantages and Disadvantages of Kanban Methodology
- The main advantage of the Kanban method is to avoid overproduction. Thus, the raw material is delivered only when it is necessary, thus reducing storage costs and losses.
- As soon as the circulation of the kanbans (labels) stops, it means that there is a problem in production. This system therefore makes it possible to detect problems quickly and to be able to act as quickly as possible.
- The Kanban approach is flexible: it is possible to suspend or shift tasks to manage blocking points or more urgent tasks.
- Finally, this method encourages collaboration within the team to solve problems.
- The Kanban method is not suitable for all industries. It is more suitable for the production of single pieces in large series (the automobile industry for example).
- A problem in the Kanban system can cause the production line to stop, just as the loss of labels can cause difficulties.
- Although the Kanban approach has been designed to standardize production to meet a constantly changing demand, the system no longer works when demand is too irregular.
- Finally, it is essential to properly train your teams in the rules of the Kanban method in order to avoid errors.
The Kanban method is mainly used in the industrial production sector. With this methodology, customer orders trigger production, the aim being to avoid as much as possible stock. This approach optimizes the team’s responsiveness, fosters collaboration to solve problems and improves the quality of work and the production processes currently being implemented.