We live in the modern era where everything needs to be done in the best way possible in the shortest possible time. Our society demands more quality in less time. In the industrial sector, it is no different. Companies are always looking for benchmark solutions every day in a world that offers more and more options.
When it comes to equipment performance, it is necessary to recognize the value of large systems that are a reference in the segment. It is the case of the OEE, overall equipment efficiency. Seiichi Nakajima introduced this indicator, but arrived in the West only after the 1980.
What makes it important?
What makes OEE a success is that it simply and directly calculates the effectiveness of a piece of equipment during its period of use, telling you how many useful items it has produced compared to how many useful items the equipment is capable of producing. In other words, with the overall equipment effectiveness, it is possible to measure and evaluate the performance of equipment. A cloud system has been widely applied in manufacturing industries as it provides a complete calculation about equipment availability, performance and compliance quality.
How to calculate OEE
Before you hire an OEE Institute to support your business progress, understand how you can calculate the OEE of your equipment.
Find out the uptime of your equipment
First, you need to know how long your equipment has been in use. Calculate the period only, excluding weekends and breaks if necessary.
Measure the time the equipment is scheduled not to operate
Now rely on the opposite formula. Only note time when the equipment is not scheduled to produce. Add up the break times, factory closed, meal breaks. In addition, other non-company issues should also be considered, such as strikes raw material issues, and missing orders.
Calculate the time the equipment stopped for other consequences
In this definition, you must add the time the equipment stopped due to an unforeseen event. For example, downtime due to equipment breakdown, shortage of electricity, shift change, product change, etc.
Count the number of good items produced
Analyze the material produced and assess how many of those are considered good. Take into account only the items that do not need any repair.
Count the number of bad items produced
Now, analyze the number of items that will not make it to market or will need some repair. To calculate how much time the equipment has available to operate, just use a simple formula in the software – ‘Available time = Operating time – Scheduled time not to operate.’
If your operating time is 20,000 minutes and your planned time to leave the equipment down is 3,000 minutes, then your available time is 17,000 minutes. It is because 20,000 – 3,000 = 17,000.
Calculate the production time
To find the KPI or key performance indicator of your equipment: Production time = Available time – Unplanned downtime. According to our previous calculation, the available time is 17,000 minutes. Moreover, assuming our equipment downtime due to unforeseen events is 4,000 minutes. Then we have 13,000 minutes of production regardless of product quality.
Calculate the number of items the equipment should produce
In this case, consider the amount the equipment would have to produce in the time it was in operation. For example, if your equipment is capable of producing a product every 30 seconds, then the number of products it should produce is – 13,000 / 0.5 = 26,000 items.
Calculate the percentage of equipment availability
To perform this SAP calculation, consider – Availability percentage = (Producing time / Available time) X 100%. Availability percentage = (13,000 / 17,000) X 100% = 76.5%.
Calculate the performance percentage of the equipment
To perform this calculation, consider – performance percentage = (Number of good items + Number of bad items) / How much should produce) X 100%
Calculate the OEE
Now yes, with all these values obtained, it is possible to discover your OEE. To do this, simply multiply the availability, percentage and quality percentages. Overall Equipment Efficiency percentage = Availability percentage X Performance percentage X Quality percentage.
Conclusion: World Class OEE
World class overall equipment effectiveness is the index used as a world benchmark by industries. The plants with the best efficiency in the world should have – availability, greater than or equal to 90%, performance greater than or equal to 95%, and quality greater than or equal to 99.9%. Note that having 85% OEE is not enough to be considered world-class, it is necessary that Availability, Performance and Quality exceed the reference values.