Lean manufacturing minimizes work-in-progress (WIP) inventory by matching production to downstream demand. In a pull/kanban system a station only pulls new work when its output buffer has space; in a push system it produces regardless, which can flood buffers.
Little's Law: WIP = Throughput * CycleTime
Pull: produce only if buffer_next < capacity
Push: produce whenever input available, ignoring downstream buffer
- Batch size — how many units move together between stations per transfer.
- Buffer capacity — maximum WIP units a station's output buffer can hold before it blocks upstream production (in Pull mode).
- Station speed — processing rate of each of the four workstations along the line.
- Push vs Pull (Kanban) — Pull mode throttles upstream stations when a downstream buffer is full, keeping WIP low; Push mode lets WIP pile up in buffers.
This mirrors real kanban systems: capping buffer capacity and pulling only on demand reduces excess inventory and shortens cycle time compared to an uncapped push line.