Glossary A–ZLetter O
OEE (overall equipment effectiveness)
OEE is a key figure for the overall effectiveness of a machine or line, calculated as the product of availability, performance and quality.
The abbreviation stands for “overall equipment effectiveness”; the result is given as a percentage.
Availability captures downtime, performance the gap to the possible cycle time, and quality the share of good parts. If a machine runs for 90 per cent of the planned time at 90 per cent of its possible speed and delivers 90 per cent good parts, the OEE is around 73 per cent. In production, shop floor screens show OEE per line or shift, often next to the three component values.
A single percentage says little about where the problem lies; the component values are more informative. The calculation depends on what counts as planned time, so OEE figures from different plants are only comparable if the definition is the same. Operators should relate the figure to machines, not to people. If it turns into measuring the performance of individual employees, the works council has to be involved.