Glossary · approach
Just-in-Time (JIT)
A production philosophy and operational discipline aimed at flowing production at the pace of customer demand by minimizing work-in-process and raw-material inventory.
JITJust in TimeJust-in-Time ProductionZero-Inventory Production
Just-in-Time (JIT) is a production approach in which the required part arrives at the station in the required quantity at the required moment; its foundations are laid in Ohno (1988) and the Toyota Production System (TPS) literature. The operational expression of the philosophy is pull production, small lot sizes, short setups, multi-skilled operators, and quality guaranteed at the source. The opposite of JIT is push production and the classical aggregate-production-planning approach based on safety stock — JIT treats WIP and finished-goods inventory not as a cost but as a 'cover over hidden problems.' In an SMB context, pure JIT is risky when demand volatility and supplier reliability are low; therefore Turkish manufacturing SMBs typically prefer modified JIT with a small safety buffer. JIT is one of the two pillars of Lean Manufacturing (the other being Jidoka — autonomation with quality stop). The Joint Replenishment Problem, aggregate production planning, and assembly line balancing topics are reframed under JIT principles. In practice JIT is deployed with the Kanban card system, SMED quick-setup techniques, and 5S workplace organisation.
Örnek
An SMB producing furniture-supplier parts in Kayseri moves from classical weekly batch production to modified JIT: 80 units per day, 2–3 days of safety stock (down from 3 weeks), and daily supplier delivery. WIP falls by 62%, lead time drops from 18 days to 5; however, one supplier delay halts the entire line within 4 days, so the safety buffer cannot be driven to zero.