Kanban Loop
A kanban loop is the closed replenishment circuit connecting a consuming point and a supplying point. Consumption triggers a signal—usually a kanban card—to replenish the exact material quantity needed. In manufacturing software, a loop is defined by a single part, supplier, customer, container, and quantity per card. It governs the physical flow of bins or cards between point of use and replenishment to maintain controlled pull, not forecast-driven push.
On the shop floor, a kanban loop acts as the operating path for bins and cards moving from point of use to replenishment and back. In a two-bin or two-card setup, operators physically walk the loop, inspect bins against the red line or signal card, scan or remove the card, pull reserve stock from the supermarket or raw-material storage, refill the bin to the maximum line, and post the transaction. That posting resets on-hand inventory and reorder status. The loop becomes a controlled pull mechanism for raw-material tracking, work-in-process, and line-side supermarket replenishment rather than a forecast-driven push process. When a downstream cell consumes a container, the signal flows upstream, triggering the exact quantity needed. The loop is sized with enough cards or bins to prevent interruption while keeping excess inventory limited, so consumption, replenishment lead time, and container quantity remain tightly aligned.
Is a kanban loop the same as a kanban card?
No. The loop is the end-to-end replenishment circuit comprising the physical path and control relationship; the card is the signal carrier that travels through that circuit. A loop can use one or two cards, but the cards are not the loop itself.
What defines a kanban loop in manufacturing software?
In manufacturing software, a loop is typically defined by a unique combination of part number, supplier, customer, container size, and cards per loop. Each control record represents one distinct replenishment loop, allowing the system to calculate required card counts and track transaction flow.
Can a kanban loop use one-card or two-card signaling?
Yes. Kanban implementations can use one-card or two-card signaling depending on how material movement and production authorization are separated. The choice affects whether production and withdrawal signals are combined or kept distinct, but both operate within a closed replenishment loop.