Eliminating Demand Variability with Mixed Model Lines

Mixing models on the assembly line smoothes demand at fabrication. Figures 11 and 12 illustrate this. This eliminates the need for a large inventory buffer between fabrication and assembly. At four and two units per day, a buffer of only one piece would suffice, A similar inventory reduction occurs on the Finished Goods side since the line is scheduled to synchronize with daily demand.

Scheduling of the assembly line might be done in either of two ways:

1. 1) A kanban system would hold a few of each finished item and the line would be scheduled and sequence to replenish the kanban stock.
2. 2) The line might be scheduled on a Make-To-Order basis and build only what customers have actually ordered.

With either system, there is no formal scheduling required upstream at fabrication because the kanban system provides the signal for what to produce and when.

Figure 12 Mixed Model Daily Demand Pattern

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