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VBF Tubing, a Dutch firm, is facing increased demand for its products, high inventory levels, and expensive setup costs. In light of these problems, the logistics manager must decide how to respond to a proposal that longer production runs be scheduled. The production, cost and market data supplied permit the students to explore the necessity and implications of changing production batch sizes on these competing priorities. In particular, the application of the traditional Economic Order Quantity can be assessed based on other facility-wide operating practices.

The vice-president Operations of Spartan Plastics, is facing a trade-off. As an avid proponent of the Toyota production system, just in time manufacturing (JIT), ISO 9001, and continuous improvement, he has reduced setup times, batch sizes, and throughput times. On the other hand, the scrap rate has shot up. This case would be appropriate for use in a production and operations course, to introduce students to the concepts of JIT and world class manufacturing.

About 15 operators work in a simple hybrid batch-flow environment to produce the Earth Buddy novelty product. The case introduces the topic of process analysis. Sufficient information is presented to introduce and discuss the following concepts in an 80-minute class: capacity, throughput time, cycle time, bottleneck identification and resolution, and work-in-process inventory accumulation and draw-down. Issues that can be explored during the discussion include: shift scheduling, the impact of cross-training, batch versus flow production, rush orders, and the impact of defects on capacity. (An Extend simulation file is available for this case, Earth Buddy - Extend Simulation file.)

A large, open pit, iron ore mine is plagued with crusher delays. The case describes the situation, provides relevant capacities and costs, and gives statistical data on the frequency and duration of crusher stoppages. The manager has to choose between holding trucks idle during crusher delays, reassigning the truck-shovel teams to waste removal, or to dump ore at an ore stockpile.

Martin Trailers Limited, which has grown rapidly, produces a line of camping trailers, which have a pronounced seasonal sales pattern. Details for the previous year's planning process, staffing levels, production outputs and costs are reviewed by the owner, with the objective of improving the management of materials in the year ahead. Sufficient information is available to perform a quantitative analysis of the aggregate planning decision and its relationship to material requirements planning.