TABLE OF CONTENTS Continuous plants tend to be relatively straightforward for setting up an uptime measurement. With some minor modification to the model of Figure 1-5, losses can generally be routinely accounted. Measuring OEE in batch and discrete plants, however, is often more difficult, partly because they generally have more discrete manufacturing steps, some of which feed multiple finished products, partly because they generally produce a larger number of products, partly because the logistics of doing the calculations is just more complex. Using the technique previously described will help to focus the measurement effort, but to illustrate the method, let's take an example from Beta's Hemp Hill plant, a batch operation, which had been measuring the following performance indicators at one of its plants for one of its key production lines:
Availability. Although the term being used was uptime, or any time the line was up and running, availability is a more accurate characterization using our model, because it did not include the effects of rate, quality, or other losses. And, because downtime was accounted separately, this number also excludes scheduled downtime.
Downtime. This is the time when the equipment is down unexpectedly, and is synonymous with unscheduled downtime losses in the model.
Changeover time. This is the time for product changeovers. In the model this was part of the changeover and transition losses.
Clear/clean/material changes. This is the time for clearing, cleaning, and setups. This also could be part of the changeover and transition losses.
No-demand...
