What Is OEE (Overall Equipment Effectiveness)? A Guide to Understanding and Improving Production Efficiency

Contents

• Introduction to OEE
• How to calculate OEE?
• Online OEE calculator
• The benefits of tracking OEE
• Breakdown of OEE
• Conclusion
• Practical use of OEE
• Role of TPM in improving OEE

Introduction to OEE (Overall Equipment Effectiveness)

OEE (Overall Equipment Effectiveness) is a fundamental indicator for evaluating the efficiency of your machine, a production line or even your manufacturing workshop as a whole. Expressed as a percentage, it varies from 0 to 100%: a score of 100% indicates fully operational equipment, while a score of 0% means that no good parts have been produced.

According to standard NF E60-182 , OEE is defined as the ratio between useful time and required time. In other words, it measures the percentage of time spent producing good parts at design rate compared to the time the equipment was available for production.

How to calculate OEE?

Alternatively, OEE can also be calculated as the ratio between the number of good parts produced and the number of parts that it would theoretically be possible to produce during the production time.

More precisely, the OEE can be broken down into three sub-indicators: it is the product of the Quality Rate (Q), the Performance Rate (P) and the Operational Availability (A).

OEE = Q × P × A These three sub-indicators provide a more detailed vision of production performance.

• Quality Rate (Q) : It represents the ratio between the number of good parts produced and the total number of parts produced. If you produced 90 good parts out of 100, the TQ is 90%.

• Performance Rate (P) : This is the ratio between the actual production speed and the theoretical production speed. If a machine can theoretically produce 100 parts per hour but actually produces 80, the TP is 80%.

• Operational Availability (A) : It is calculated by dividing the actual operating time of the machine by the available production time. If a machine runs 8 hours in a 10 hour day, the DO is 80%.

OEE, Q, P, and A calculator

This calculator helps you determine your OEE (Overall Equipment Effectiveness), Quality Rate (Q), Performance Rate (P), and Operational Availability (A) based on your input data such as the number of compliant products, total number of products, actual and theoretical cycle times, actual production time and opening time. Simply enter your data in the fields below and click "Calculate" to get your results.

Simplified calculator: Online OEE calculation.

Actual Cycle Time (in minutes): This is the average time currently observed to produce a product or to complete a production cycle. This time can be affected by things such as Failures (if a machine stops for a period of time) or Performance Losses (if the machine runs slower than expected due to micro shutdowns or cadence deviations) .

Theoretical Cycle Time (in minutes): This is the ideal or expected time to produce a product without any interruption or inefficiency. This would be the cycle time if no Scheduled Shutdown, Organized Malfunction or Series Change occurred.

Actual Production Time (in hours): This is the total time during which production actually took place, taking into account Breakdowns and Organized Malfunctions. For example, if you started an 8 hour work day but had 1 hour of breakdown and 1 hour of training (organized dysfunction), the actual production time would be 6 hours.

Opening Time (in hours): This is the total time planned for production, before taking into account any shutdowns or interruptions. This would include Operating Time, Scheduled Shutdowns, and any other time during which production could theoretically take place.

The benefits of tracking OEE

OEE is a performance indicator that allows production to be challenged. It is particularly useful when monitored on the bottleneck resource, that is to say the element which limits the production flow. OEE monitoring helps address operational challenges and identify areas of efficiency to improve. It is recognized as the benchmark indicator in the context of TPM (Total Productive Maintenance), a quality management practice that promotes maximum productivity. The implementation of OEE, as an evaluation and management tool, supports the proactive approach of engineers and technicians in the quest for operational excellence, by highlighting optimization possibilities for more robust and efficient production. competitive.

Breakdown of OEE

Usable time, net time, operating time, required time, open time, and total time are all important elements in understanding and calculating OEE . For example, net time is obtained by adding non-quality time to useful time, which represents the time theoretically spent producing bad parts.

To obtain the operating time, we add the cadence differences to the net time. These deviations represent the time lost in producing at a rate lower than the nominal rate.

The required time is calculated by adding unplanned stops to the operating time. These shutdowns, which are often the main cause of OEE losses, represent the time spent shut down by the installation.

OEE = Tu / Tr

Conclusion: The importance of OEE in improving production

In summary, OEE is a key indicator that, when properly analyzed and interpreted, can provide valuable information on production performance and enable improvement measures to be implemented. For any production manager, the use and understanding of OEE is essential.

Tracking this metric helps quickly identify inefficiencies and production issues, and determine what actions need to be taken to improve performance. Whether in terms of quality, performance or operational availability, every aspect of production can be optimized through the use of this indicator.

To learn more about OEE, including how it's calculated, its benefits, and implementation strategies, check out this video :

The use of OEE in practice

In practice, monitoring OEE can help identify various issues such as production defects, unplanned shutdowns, and supply or personnel issues. Identifying and resolving these issues helps improve production efficiency and maximize yield.

Additionally, OEE can be used to track the progress of continuous improvement initiatives, and to identify areas where additional investments in equipment or staff training may be beneficial.

The video below presents Excel software including an advanced dashboard used for tracking OEE (Overall Equipment Effectiveness). Please note that the video is in English.

The role of TPM (Total Productive Maintenance) in improving OEE

TPM is a methodology that aims to maximize the efficiency of production equipment. It includes a set of tools and techniques that, when used in conjunction with OEE, can help reduce downtime, increase product quality, and improve overall production efficiency.

Finally, let's remember that OEE is not only a tool to evaluate current performance, but also an indicator that, when tracked over time, can help anticipate future problems and develop strategies proactive measures to improve production efficiency.

It is important to understand that the objective is not to achieve 100% OEE at all costs, but rather to aim for continuous improvement and to optimize productivity and quality in a sustainable manner. With OEE as an ally, every company can embark on the path to production excellence.

To go further in optimizing your productivity, we invite you to consult our file model: OEE Excel Dashboard for calculating OEE and monitoring the performance of your production line. These resources will help you put what you've learned into practice and take action to improve your production performance.

For more advanced needs, check out our OEE software , specifically designed to fit the unique challenges of various industry sectors. Our scalable system offers a multitude of features suitable for all roles within your business. From production staff, benefiting from streamlined data entry, to managers who leverage deep insights for strategic decision-making, our OEE software encompasses all aspects of productivity optimization. Visit our overview page to see how our software can help you take the leap toward industry-leading production efficiency.

To guide you towards the solution best suited to your needs , visit our selection of the best OEE software , where functionality and innovation meet to meet your industrial needs. Let Digital Factory guide you into the era of renewed efficiency.