This performance metric takes center stage as a growing number of users turn to it both to boost the efficiency of their equipment and to compare the performance of machines and production lines.
“OEE is a measure of the utilization of an asset’s productive capacity in terms of three factors—availability, performance (throughput), and quality—expressed as percentages of their ideal values. For example, performance is the actual production rate or throughput expressed as a percentage of the designed capacity of the equipment.”
“…OEE can sometimes be useful for comparing identical and nearly identical equipment, … the metric is not always suitable for this purpose. … OEE is the product of only three factors: performance, quality and uptime. “It doesn’t factor in things like sales and the importance to the business,” he says. “Those are things that OEE just doesn’t have any kind of theoretical basis to address.”
“For this reason, comparing equipment often makes more sense with other metrics, such as the total effective equipment performance (TEEP), the product of OEE and a loading factor computed by dividing planned uptime by calendar time….”
“Users often neglect this loading factor when comparing lines. … The client never planned to run the lines for the same amount of time each day,” he says. So, he maintains that it was unfair to compare their OEEs.”
“Another limitation of OEE, as well as TEEP, is that the metric does not consider sales and the relative contribution that a machine or line makes to the overall business. “You have to factor in the return on investment,” says Kemmann. “If similar lines with different OEEs are serving different customers where your pricing structure is different, then comparing OEEs will not be helpful because you’re not factoring in the effects of their relative value to the business.””
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