### OEE Calculation Improvements with ShopFloorConnect

#### Availability x Performance x Quality = OEE

### How Traditional OEE is Calculated

### Availability

### Performance

### Quality

##### The Drawbacks of “Traditional” OEE Calculations

But, traditional OEE calculations come up short in many applications. While the Availability and Quality metrics can be universally applied to all machine types, difficulty arises when the traditional Performance metric is applied to discrete manufacturing processes where the true “ideal production rate” is more dependent on the parts being manufactured than the machine itself.

Consider the following OEE Calculation example:

A machining center making ‘Part A’ produces 6 parts per hour. After a job change the same machine produces ‘Part B’ at a rate of 12 parts per hour. According to “traditional” OEE calculations, the “Part B’ is running at twice the efficiency of “Part A’. However, let’s say that under ideal circumstances, our machining center is actually capable of producing ‘Part A’ at a rate of 7 parts per hour, and the much simpler “Part B” at 30 parts per hour.

In actuality, the machine was running at 86% efficiency while making Part A, and only 40% efficiency for Part B.

The errors inherent in traditional OEE calculations can be manually factored out on a job-by-job basis, but this task becomes extremely difficult when trying to summarize overall equipment effectiveness over a longer period of time. In addition, the calculations required to properly “weight” jobs of varying length become very complex.

##### How ShopFloorConnect Calculates OEE

In applications where a machine must make more than one cycle to produce a part, ShopFloorConnect automatically divides the ideal rate by the number of cycles required to make the part.

The ShopFloorConnect system keeps a running total of the actual parts produced by the machine, as well as the number of parts that could have been produced according to the ideal rates and multipliers. This allows LETS to accurately summarize performance over time, regardless of the lengths of the jobs that ran in the machine. LETS automatically “weights” the percentages according to job length.

### ShopFloorConnect OEE Calculation Example:

The second job (which ran for two hours) produced a part every 6 cycles of the machine. The Ideal Rate for this job was 50 cycles per minute. The theoretical maximum number of parts that could have been produced by this job was 1000; the machine produced 950.

The final job (which ran for one hour and 20 minutes) produced one part per cycle, with an ideal rate of 80 cycles per minute. The theoretical maximum number of parts that could have been produced by this job was 6400; the actual number of parts made was 5900.

During the 338 minutes of running time in our example, the machine could have theoretically made a total of 48,800 parts for all jobs combined, but produced an actual total of 45,515. The performance percentage is calculated by dividing the actual number of parts by the theoretical maximum:

### OEE Calculation Improvements with ShopFloorConnect

- Make the most out of a limited amount of investment capital
- Avoid making inappropriate equipment purchases
- Free up capacity to better compete for new business
- Quickly highlight the greatest areas of improvement to provide the greatest return on asset
- Prioritize Lean initiatives
- Decrease costs through waste elimination
- Shorten equipment ROI through increased utilization
- Reduce investigation time for root cause analysis
- Directly tie production efficiencies to fiscal reporting