The OEE is an essential indicator if your objective is to measure the productive efficiency of the industrial equipment of your factory. With the Mapex Production module you can calculate this KPI in a totally reliable way and in real time, to move towards continuous improvement and Industry 4.0 operations.
The OEE (acronym for Overall Equipment Effectiveness) is an infallible indicator when it comes to measuring the productivity and efficiency of all the manufacturing processes of any industrial company. Through calculating the OEE, organizations can identify their pain points or possible inefficiencies and deploy improvements faster to adapt to Industry 4.0 environments.
Quantifying the OEE brings multiple advantages to companies. We are talking about an indicator that allows you to discover the origin of your most frequent productivity losses, such as bottlenecks. In addition, it helps companies to increase the quality of their production and the level of satisfaction of their customers, since detecting problems quickly means less rework, defective units and delivery times.
On the other hand, this KPI gains value when obtained automatically and based on reliable, up-to-date information in real time. This is only possible thanks to the implementation of an MES system, such as the Mapex Production module, a tool that is capable of calculating the OEE with total accuracy; that saves companies a lot of time and effort in the data collection process, and that provides reports so management can make the best decisions.
How to calculate the OEE
OEE is a standard metric (used by major manufacturers around the world), scalable and always calculated taking into account three parameters: availability, performance and quality. Let’s examine the significance of each of them.
Availability
Availability is calculated by dividing the productive time or time in which the equipment has been operating without downtime of any kind by the planned production time (or theoretical availability). Holidays or plant or line closures, stoppages due to planned maintenance or other equivalent causes are not included in the planned production time.
The result is the loss due to stoppages that have occurred during production, such as format changes, breakdowns, material shortages, etc.
Performance
Performance is calculated by dividing the time taken to produce the actual units manufactured or productive time (obtained from the above availability calculation) by the theoretical production that should normally be obtained in that time according to the theoretical maximum output of the machine or process.
The result is loss of performance or excess time spent producing the actual units manufactured.
Quality
Quality is calculated by dividing the theoretical time required to produce the actual quantity manufactured or productive time (after deducting the availability and performance losses mentioned in the previous points) by the theoretical time required to produce the OK production according to the theoretical maximum output of the machine or process (or effective time).
The time spent in producing the defective or rejected units is thus considered a loss.
The final OEE indicator is extracted by multiplying the three previous indicators, resulting in the total effectiveness of the machine or process, including all losses.
OEE can also be derived automatically without having to calculate each of its indicators by directly dividing the effective time (theoretical production time of the good units) by the total planned production time, as explained in the performance section.
The following video shows a practical example of OEE calculation:
A continuous improvement and Industry 4.0 metric
Obtaining the OEE of an equipment, a production line or the entire factory is only the first step in implementing a culture of continuous improvement in a company. Thanks to this indicator, organizations receive insight into where and at what point in the production process availability, performance and/or quality problems arise.
However, this metric is of no use if, after being aware of it, an improvement plan is not designed and implemented to exceed 85% in OEE, the percentage required to achieve what is known as “excellence in manufacturing” or World Class Manufacturing and a long-term goal for a large number of companies.
When an OEE still has significant room for improvement, various corrective actions can be taken, for example:
- Bet on preventive maintenance to reduce machine availability losses caused by breakdowns and/or improve machine performance.
- Reassign operators; reorganize raw or semi-finished material flows to reduce waiting times or optimize format change times to reduce stoppages in the production process and, thus, improve overall productivity.
- Apply quality control plans in the production process to ensure that the manufactured parts meet the quality standards required by the customer, thus reducing costs due to rejections or rework.
MES systems: a strong ally in OEE optimization
A company that is already calculating its OEE manually and is unable to exceed the 50% barrier should consider a MES system to support this measurement and to keep track of its corrective action strategy.
As mentioned above, the implementation of this solution multiplies continuous improvement possibilities for OEE: it provides data on all resources and helps companies to analyze and detect problem areas and losses in availability, production capacity and quality in a more comprehensive, accurate way.
Finally, an MES system also provides a useful tool to gather an overall view of OEE in companies with more than one production plant. This is one of the main advantages of implementing the Mapex Production module, a platform that offers real-time productivity and efficiency indicators for each factory, area, machine and/or operator to increase the organization’s competitiveness and return on investment (ROI).
