One point which we all understood was that our overall cycle times for our product dictated the level of work-in-progress (WIP). If we have an average lead time of four weeks for the components going through our welding department, then we will have an average WIP level of four weeks’ worth of production.

The Japanese had addressed this in a number of ways, primarily in a fundamental redesign of factory layout and process flow. We learned that rather than have one area of the plant for presses, another full of lathes, another drills, and so on, they had switched to «focussed factories» where each area of the plant made a particular type of component. The unit making drive shafts had saws, followed by milling, turning, drilling and so on. These focussed units then brought the opportunity for multi-skilling and teamwork which helped to provide for productivity improvements – as well as significantly reducing the movement of materials through the factory.