In the latest issue of the AME’s Target magazine, Peter King explains how he has applied the cell concept in process plants, but his cells are virtual, meaning that their implementation does not involve relocating equipment. In the case of synthetic rubber at Dupont’s plant in Louisville, KY he reports decreasing scrap and lead time by 28%, and decreasing finished goods inventory by 50%. There is no mention of improvements in Productivity, WIP and Raw Materials inventory, or Space Requirements.
While these improvements are substantial and respectable, they are not up to cell benchmarks: reductions of 80% to 90% in lead time, inventory and defect rates, with a 30% to 50% increase in productivity, all in 25% to 30% less space. But that cannot be achieved without moving equipment…
If you can’t move the equipment, I prefer to call it managing monuments than implementing cells. Since you can’t get from managing monuments the order-of-magnitude performance boosts that you get from cells, I prefer to keep the distinction in sharp focus rather than blur it by pretending that “virtual cells” are cells. Where cells apply, they are wonderful, but they are not a panacea. Even in discrete, mechanical manufacturing plants, there are often a few areas like, Heat Treat, Electroplating or Painting, where cells are difficult or impossible for now, and the skill of managing monuments is necessary.