One-piece flow in Lean refers to which production approach?

One-piece flow in Lean refers to which production approach?

• A. Batch Production
• B. Continuous Flow With Small Lot Sizes
• C. High Setup Times
• D. Flexible Automation

Answer: (B)

One-piece flow emphasizes moving work through the process one item at a time, or in very small lots, with minimal waiting between steps. This creates a smooth, nearly continuous flow rather than batching large quantities. By keeping work-in-process small and lead times short, problems are visible sooner, quality issues are caught early, and the system responds quickly to changes in demand. It also supports pull-based production, where output is driven by actual demand and aligned to takt time. This is why the description that fits best is continuous flow with small lot sizes. Large batch production increases WIP and lead time, obscures defects, and makes the system less responsive. Long setup times make small-lot, one-piece flow impractical, since changing over takes too long. Flexible automation isn’t the defining feature—one-piece flow can be manual or automated, but the core idea is keeping lots small to maintain a steady, pull-driven flow through the line.

One-piece flow emphasizes moving work through the process one item at a time, or in very small lots, with minimal waiting between steps. This creates a smooth, nearly continuous flow rather than batching large quantities. By keeping work-in-process small and lead times short, problems are visible sooner, quality issues are caught early, and the system responds quickly to changes in demand. It also supports pull-based production, where output is driven by actual demand and aligned to takt time.

This is why the description that fits best is continuous flow with small lot sizes. Large batch production increases WIP and lead time, obscures defects, and makes the system less responsive. Long setup times make small-lot, one-piece flow impractical, since changing over takes too long. Flexible automation isn’t the defining feature—one-piece flow can be manual or automated, but the core idea is keeping lots small to maintain a steady, pull-driven flow through the line.