Kanban — Pull-Based Replenishment
Kanban (Japanese for 'signal card') is the lean-manufacturing principle of pull-based replenishment: downstream consumption triggers upstream production or supply. Originated at Toyota in the 1950s, kanban became a cornerstone of lean production worldwide and remains widely used in DACH automotive supply, machinery and high-volume manufacturing. The original paper-card system has been largely replaced by electronic kanban (eKanban), integrated with ERP and increasingly with supplier portals.
How kanban works
The classical kanban system uses bins of standard size with associated kanban cards. When a downstream workstation consumes a bin, the kanban card returns to the upstream workstation as a production signal. Production happens only against returned cards — never speculatively, never to forecast. The result is a tight coupling between actual consumption and actual production, with WIP capped by the number of kanban cards in circulation. Kanban applies at multiple levels: within a production line (workstation-to-workstation), between production cells, between production and finished-goods warehouse, and between buyer and supplier (supplier kanban). Each level operates on the same pull-signal principle.
Electronic kanban (eKanban)
Modern eKanban replaces physical cards with electronic signals: barcode scans, RFID tags, weight-sensors on bins, manual replenishment buttons. The signals flow through ERP or dedicated kanban-management software (Ultriva, Replenish by Demand Driven Technologies, SAP Kanban, abas Kanban). Benefits over paper cards: real-time visibility of kanban status, lower risk of lost cards, integration with planning and procurement systems, automated reorder triggering. eKanban scales to multi-plant and supplier networks where paper cards become impractical. ERP integration ensures that kanban replenishment shows in ATP and capacity views, and feeds purchasing for supplier kanban.
Kanban versus MRP
Kanban and MRP are philosophically opposite: MRP is push-based (forecast drives production), kanban is pull-based (consumption drives production). Most real-world manufacturers use both, applying each where it fits the operational reality. MRP suits long-lead-time, high-variety, low-volume parts and project-based production. Kanban suits short-lead-time, low-variety, high-volume parts with stable demand. The boundary is set by ABC-XYZ analysis of part categories: A-X (high-value, stable-demand) parts run on kanban; C-Z (low-value, erratic-demand) parts run on classical MRP. Modern ERP supports per-part planning-strategy assignment, allowing the right tool for each part category within a single system.
Practical application in DACH
In DACH manufacturing, kanban is most prevalent in automotive supply (JIT/JIS deliveries to BMW, Mercedes, Volkswagen Group), high-volume electronics, fasteners, consumer goods packaging and pharmaceutical primary materials. Implementation effort: 3-9 months for a typical mid-market manufacturer transitioning a single product line from MRP to kanban, requiring stable demand, reliable suppliers and operational discipline. Common failure modes: kanban applied to unstable-demand parts (system oscillates), inadequate supplier capability (kanban cards return without replenishment), or insufficient WIP discipline (operators fill bins beyond kanban quantities). Successful kanban programmes consistently report 20-50% WIP reduction and 10-30% lead-time reduction for the parts under kanban.