TPU (Time Per Unit) is similar to LMPU. Both measure time to produce a single part. The difference is that LMPU uses Total time, and TPU only uses Available time. TPU is a good metric to measure operator performance.
Calculation
Calculating TPU for a single pitch
We use the following formula to calculate TPU for a single pitch:
TPU = (Operator Count × (Planned Production Minutes - Downtime)) ÷ Actual
Calculating TPU for multiple pitches
Since Operator Count is not constant for multiple pitches, it cannot be averaged. It cannot be summed, either. In order to calculate an accurate TPU, Operator Count must be abstracted from the above calculation. Once abstracted, we can perform the TPU calculation using the sums of the abstracted pieces.
TPU = sum(Pitch Active Labor Minutes) ÷ sum(Pitch Actual)
Pitch Active Labor Minutes = Pitch Operator Count × (Pitch Planned Production Minutes - Pitch Downtime)
Example
Pitch Number | Operator Count |
Planned |
Downtime | Actual | Active Labor Minutes |
TPU |
1 | 1 | 60 | 15 | 100 | 45 | .45 |
2 | 2 | 60 | 0 | 150 | 100 | .67 |
3 | 2 | 60 | 15 | 100 | 90 | .9 |
4 | 3 | 60 | 0 | 200 | 150 | .75 |
Average | 2 | - | - | - | - | - |
Sum | - | 240 | 30 | 550 | 385 | .7 |
Total TPU: 385 / 550 = .7
Quick Tip: The same theory and calculations apply to NPM: Non-Production Minutes
TPM must be calculated for each pitch and then summed because Operator Counts vary from pitch to pitch: an average operator count cannot be used to calculate NPM. Hence, the pitch by pitch basis.
Prorating
This metric will be prorated in certain areas of the application. Please see the article on Prorated Production Metrics for more information.