Kanban Bin Cycle
A Kanban bin cycle is a repeating pull replenishment loop in a visual inventory system. Consumption from one bin triggers replenishment of that bin while a second reserve bin covers demand until the refill arrives. The cycle is sized so one bin covers lead-time demand—average usage during replenishment lead time, often with a safety factor when variability exists.
On a shop floor, the bin cycle keeps high-velocity, low-complexity parts such as fasteners, clips, fittings, and labels at the point of use. An operator consumes from the active bin until it empties, then switches to the reserve bin and sends a replenishment signal through a kanban card, RFID tag, or visual marker. That signal flows to procurement, supermarket personnel, or an internal milk-run, who refill the emptied bin with a predetermined quantity. In warehousing, the same logic powers supermarket replenishment: each bin-empty event becomes a controlled demand that can be converted into an internal transfer, production order, or purchase order. The technical objective is to synchronize consumption rate, replenishment quantity, and replenishment lead time so the reserve bin prevents line interruption while avoiding excess inventory. In practice, bin quantity is calculated from daily usage multiplied by lead time, then adjusted for packaging constraints, variability, and supplier minimums.
What is the control variable in a Kanban bin cycle?
The control variable is the inventory signal at depletion—the empty bin or its attached kanban card—not a forecasted requirement.
How is bin size usually determined?
By usage rate x replenishment lead time, then modified with a safety factor or safety stock when variability exists.
Where does the cycle fail most often in manufacturing?
At the interface between consumption and replenishment—miscounts, late empty-bin signaling, inaccurate lead times, and receiving delays are the most common failure points.