Kanban is a Japanese word that when translated literally means « visible record » or « visible part ». In general context, it refers to a signal of some kind. Thus, in the manufacturing environment, kanbans are signals used to replenish the inventory of items used repetitively within a facility. The kanban system is based on a customer of a part pulling the part from the supplier of that part.
The customer of the part can be an actual consumer of a finished product (external) or the production personnel at the succeeding station in a manufacturing facility (internal). Likewise, the supplier could be the person at the preceding station in a manufacturing facility. The premise of kanbans is that material will not be produced or moved until a customer sends the signal to do so.
The typical kanban signal is an empty container designed to hold a standard quantity of material or parts. When the container is empty, the customer sends it back to the supplier. The container has attached to it instructions for refilling the container such as the part number, description, quantity, customer, supplier, and purchase or work order number. Some other common forms of kanban signals are supplier replaceable cards for cardboard boxed designed to hold a standard quantity, standard container enclosed by a painting of the outline of the container on the floor, and color coded striped golf balls sent via pneumatic tubes from station to station.
Kanbans serve many purposes. They act as communication devices from the point of use to the previous operation and as visual communication tools. They act as purchase orders for your suppliers and work orders for the production departments, thereby eliminating much of the paperwork that would otherwise be required. In addition, kanbans reinforce other manufacturing objectives such as increasing responsibility of the machine operator and allowing for proactive action on quality defects. However, kanbans should not be used when lot production or safety stock is required because the kanban system will not account for these requirements.
For more information: KANBAN