Enter one shift and see where the time went, in minutes and parts.
| Loss | Minutes | Parts | % of time |
|---|---|---|---|
| Downtime | 52.0 | ≈ 520 not made | 10.83 |
| Speed | 48.0 | ≈ 480 not made | 10.00 |
| Quality | 15.0 | 150 rejected | 3.13 |
Overall Equipment Effectiveness (OEE) shows how much of the planned production time turned into good parts at the ideal speed. It splits the loss into three: Availability (the machine stopped), Performance (it ran slower than the ideal cycle) and Quality (it made parts that were not good first time). The calculator also turns each loss into minutes and parts, so you can see where the time went and which loss to attack first.
OEE follows the definition of Nakajima and the Japan Institute of Plant Maintenance (TPM), and the result is compared with the world-class levels for each factor. The calculation is tested against a published worked example.
The data behind “Try an example”: an 8-hour shift (480 min), 52 min of unplanned stops, ideal cycle 6.0 s, 3,800 parts made, 3,650 good.
| Result | Value | Loss |
|---|---|---|
| Availability | 89.17% | 52 min stopped |
| Performance | 88.79% | 48 min of slow running |
| Quality | 96.05% | 150 parts (15 min) |
| OEE | 76.04% | Typical, room to improve |
The two biggest losses, stops and slow running, are almost equal, so both are worth a look before quality.