Changeover Time

Changeover time measures the total elapsed time between the last good part of a production run and the first good part of the next run. This period includes all activities required to prepare the equipment for the new product. Common activities are cleaning, swapping tools or dies, loading new materials, and adjusting machine settings.

Reducing changeover time is critical for operational efficiency. Long changeovers create significant downtime, which reduces available production capacity. This often forces manufacturers to run larger batches to minimize the frequency of changeovers. Shorter changeover times increase manufacturing flexibility, enabling smaller batch sizes and supporting just-in-time (JIT) production.

Manufacturers use methods like Single-Minute Exchange of Die (SMED) to shorten changeovers. The SMED process analyzes every step of the changeover. It separates internal setup (tasks done when the machine is stopped) from external setup (tasks done while the machine is running). The goal is to convert as many internal tasks to external ones as possible. For example, an operator can pre-stage tools and materials for the next job while the current job is still running.