CPIM Practice Exam

What happens when preceding work centers produce faster than a bottleneck can handle?

1. Overall system throughput increases, up to a limit.

2. Overall system throughput increases indefinitely.

3. The constraint buffer grows in duration.

4. There is a reduction in work-in-process inventory.

The correct answer is: The constraint buffer grows in duration.

When preceding work centers produce faster than a bottleneck can handle, the correct outcome involves the dynamics of the system's throughput and work-in-process inventory. The correct answer reflects the scenario where the bottleneck, or constraint, is unable to keep pace with the upstream production, causing excess inventory to accumulate. In this situation, the constraint buffer grows in duration since the operations upstream are producing at a higher rate. Consequently, this surplus results in an increasing amount of work-in-process inventory waiting to be processed by the bottleneck. The other options can be discussed in terms of their applicability: system throughput does not increase indefinitely because it is ultimately limited by the bottleneck's capacity. While throughput may initially improve up to a certain limit, once the bottleneck is reached, further increases in upstream production do not lead to greater overall system throughput. Furthermore, having faster production at upstream work centers typically leads to a rise in work-in-process inventory rather than a reduction. Thus, the correct answer highlights the behavior of the constraint in the presence of faster preceding operations.