Kanban replenishment
Kanban replenishment is a pull-based reorder system. Parts are released to the supplier the moment on-hand stock drops below a set threshold (often signaled by an empty bin or a scanned card), instead of being scheduled out from a forecast. The reorder is a consumption signal, not a planning calculation.
Part of the Procurement Glossary
How it works in practice
A part on kanban has a set on-hand target (say, two bins of 50 each) and a trigger point. When the floor pulls down to the trigger, an empty bin or a scanned card signals the supplier to ship a refill against a standing blanket PO. The buyer is not running an MRP report and placing a new PO every cycle. The release fires on consumption.
Most production buyers work in a mixed environment: some parts on kanban, some on MRP. A C-class fastener might be on a two-bin kanban with a local distributor while the same buyer is running scheduled releases for machined parts under blanket POs and one-off POs for project work. The buyer's job under kanban is different: less placing, more monitoring the signals, the on-hand levels, and the supplier's ability to keep up with the pull rate.
A note on the term: "kanban" is also used in software development for work-in-progress boards (Trello, Jira). The two are unrelated. The manufacturing usage described here predates the software adaptation by several decades and means something specific: a physical or electronic pull signal tied to inventory consumption.
Why it matters
Kanban shrinks the buyer's order-placement workload on high-volume, predictable parts and pushes accountability for replenishment timing back toward the supplier. When it works, the line never runs short and the buyer barely thinks about those parts. When it breaks (the supplier misses a release, the pull rate spikes, the kanban quantity is set wrong) the line runs out fast because there is no forecast cushion.
The risk is invisibility. A scheduled PO has a date on the calendar. A kanban release is a signal that fired, or didn't. If you are not watching, the first sign that the system stopped working is an empty bin and an idle workstation.
Tips
Treat each release as an open PO
A kanban release is a delivery commitment with a date and a quantity, the same as a scheduled release on a blanket. Track each one through to receipt; do not assume the system runs itself.
Watch the pull rate, not just the on-hand
If consumption climbs and the kanban quantity stays the same, the cycle gets shorter and the supplier eventually cannot keep up. Recheck the math when demand shifts.
Keep a non-kanban fallback for critical parts
For parts that would stop the line if the kanban broke, hold a documented fallback (an emergency PO process, a second source, a small safety buffer outside the kanban) so a missed release is not a line-down.
How PO-Relay helps
PO-Relay tracks each kanban release the same way it tracks any other open PO line. Open Loop Tracking watches the release through acknowledgment, fulfillment, shipment, and receipt; the Parts Dashboard shows every active release in one table so a missed signal does not hide. The morning briefing surfaces releases that are silent or approaching their target date without an ASN.
PO-Relay does not run the kanban math itself. The on-hand thresholds, bin counts, and pull-rate calculations stay in your ERP or kanban-management system. PO-Relay's contribution starts the moment a release is created or a release email lands in your inbox: from there, it stays on the loop until the parts arrive.