Scheduled Versus Flow Manufacturing

The differences between scheduled manufacturing and Demand Flow manufacturing are substantial, significant, and many. Among them are fundamental differences in strategy, objectives, methodology, techniques, and the utilization of people. They also differ in their underlying goals. Work-order-based, scheduled manufacturing strives for high productivity and strong performance on key tracking metrics. In contrast, Demand Flow manufacturing aims for demand-driven production with minimal in-process inventory and the highest standard of process capability. Essentially, a flow manufacturer can produce in hours or days what may take weeks for a scheduled manufacturer to produce. And the flow manufacturer does this with greater manufacturing output, substantially higher quality, reduced work-in-process dollars, less workspace, reduced scrap and rework materials, increased labor efficiency, and reduced material costs.

Scheduled Production Philosophy

Work-order-driven manufacturing plants are typically designed around functional production departments. Also, they usually have a large storeroom for raw materials and subassemblies. Production follows the scheduling of a fabricated part or subassembly.

These items are then routed from functional department to department based on the product's or subassembly's scheduled batch or lot quantity. Functional work centers and departments arrange their machinery and assembly areas to meet the requirements of this routing.

For example, several similar punch presses will be grouped together into a single functional press department work center. This functional arrangement could also apply to functional subassembly and test areas (see Figure 3.1).

Figure 3-1: Scheduled Manufacturing Plant

In scheduled manufacturing, raw material waits in the storeroom. Once the assembly or fabricated...