Criteria to measure Overall Equipment Effectiveness
The criteria considered to measure equipment effectiveness:
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Availability
The machines available time for production. That is the potential production time and actual production time.
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Performance
The machines performance rate. That is the potential output and actual output.
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Quality
The machines quality rate. That is the actual output and the output that meets the specification.
Example
Based on the above example OEE calculation is as follows:
Availability rate: The potential production time of 480 minutes. Due to downtime of the machine, the actual production time is 360 minutes.
The machine's availability rate is 360 minutes (actual) / 480
minutes (potential) * 100 = 75%
Performance rate: For the actual production time, the potential output is 3600 pieces. Due to performance loss the actual output is only 2880 pieces.
The machine's performance rate is 2880 pieces (actual) / 3600
pieces (potential) * 100 = 80%
Quality rate: For the 2880 pieces that are actually produced, only 2736 pieces meet the required specifications.
The machine's quality rate is 2736 pieces (as per standard) /
2880 pieces (actual) * 100 = 95%
The lost time, lost output and lost product are considered for OEE calculation consequently:
Overall Equipment Effectiveness = Availability x Performance x Quality