A Cell is a compact grouping of people, machines and tools arranged in the sequence of operations required to complete a family of similar products. It is the physical embodiment of flow, designed specifically to eliminate the waste of transport, waiting and handoffs between departments.
Machines are placed close together in process order, often in a U-shape so operators can move efficiently between stations. Tools and materials sit at point of use. Work moves from operation to operation in single pieces, ideally without ever sitting in a queue. Multi-skilled operators run several machines each, matching cycle times to takt across the cell.
In a departmental layout, a part travels far between machines and waits at each queue, most of its lead time is transport and waiting. In a cell, the same part flows from station to station in seconds, with no handoffs, no batching and no long queues. Lead time drops dramatically, quality improves because defects are caught by the next operator immediately, and floor space shrinks.
Start with the product family, parts that share a similar routing. Map the required operations in sequence. Rebalance work content so each station's cycle time matches takt. Size the cell for the demand it will serve. Design in the flexibility to flex up and down with volume by adding or removing operators without redesigning the cell.
Cellular manufacturing is one of the most powerful lean layouts. It replaces the traditional department-based factory with a series of small, self-contained flow lines that respond quickly to demand and expose problems immediately. See the Cellular Manufacturing entry for the broader concept.
