How to use it
- Enter the planned production time for the period in minutes.
- Enter the stop time: breakdowns, changeovers and other unplanned stops in that period.
- Enter the ideal cycle time per part in seconds.
- Enter the total parts produced and the good ones (right first time, no rework).
- Read OEE, availability, performance and quality.
Formulas
- Run time = planned time − stop time.
- Availability = run time ÷ planned time.
- Performance = (ideal cycle time × total count) ÷ run time.
- Quality = good count ÷ total count.
- OEE = availability × performance × quality = (good count × ideal cycle time) ÷ planned time.
Worked example
An 8-hour shift with 480 minutes planned, 60 minutes of stops, an ideal cycle time of 1.2 s, 18,000 parts made and 17,100 good:
- run time 420 min, availability 420 ÷ 480 = 87.5 %;
- performance 1.2 × 18,000 ÷ (420 × 60) = 21,600 ÷ 25,200 = 85.71 %;
- quality 17,100 ÷ 18,000 = 95 %;
- OEE = 0.875 × 0.857143 × 0.95 = 71.25 %.
A perfect shift would give 28,800 ÷ 1.2 = 24,000 good parts, so 6,900 were lost.
Tips
- Find the biggest loss. The three factors show whether to work on stops, speed or scrap first.
- Keep the ideal cycle time fixed when comparing periods, or the performance figure is not comparable.
- Small stops that are not logged show up as lower performance instead of lower availability.