OEE Reporting
Overview
Overall Equipment Effectiveness, or OEE, is a method of evaluation and improving the efficiency of manufacturing processes.
OEE has frequently been used in Total Productive Maintenance (TPM) and Lean Manufacturing programs, and provides a means for measuring the effectiveness of such initiatives, through its framework o calculate production efficiency.
Based on OEE calculations, root causes can be pinpointed with ease, bottlenecking can be quickly identified and intuitive decisions can be made regarding plant equipment and machinery.
OEE Calculation
Calculation Factors
There are three factors, or ratios, that come into play when calculating OEE: availability, performance, and quality. OEE is calculated by multiplying these three factors together:
- Availability% * Performance% * Quality% = OEE%
- Availability is measured by dividing actual running time by planned machine production time. Planned downtime is excluded from this calculation.
- Performance takes into account speed loss and is calculated by dividing the actual production rate of a machine by the theoretical (ideal) rate.
- Quality is determined by dividing the amount of good pieces/parts produced by the total pieces produced in a certain timeframe
Example Calculation
Suppose that in a twelve hour shift, a machine was scheduled to run ten hours, but it only ran for eight. This means that the availability of the machine was 8/10, or 80%.
Let's say that based on the rating of the machine, it would ideally produce 20,000 pieces in those eight hours. If it only produces 15,000 pieces, this means that the performance of the machine (due to speed loss) is 15,000/20,000, or 80%.
If only 12,000 out of the 15,000 pieces produced are usable, this indicates that the quality of the machine is 12,000/15,000, or 80%.
OEE is the product of these three figures. Thus, the OEE for this example machine is:
- 80% * 75% * 80% = 48%
Illustration
OEE Benefits
OEE helps companies focus on improving the performance of plant machinery already in place and decide when to purchase new equipment. The greatest areas of improvement can be determined, allowing for a better return on asset.
The OEE formula is also excellent for benchmarking. It is an easy-to-understand figure that can be displayed to personnel, which makes for a good motivational tool. By allowing employees to understand machine availability, performance and quality, they will be able to strive for higher OEE numbers.
RtDuet™ OEE Reporting Engine
RtDuet's OEE Reporting Engine will allow users to leverage their PI System to specifically report OEE across their companies.
RtDuet, a flexible system which utilizes Microsoft technology, leverages the power of PI RtAnalyics to automatically deliver real-time, client-defined downtime or industry standard OEE reports, complete with shift and cause metadata.
