3. Maintain improvementsSince OEE is used in very different and unique manufacturing processes, understanding how OEE is used in each process is critical to achieving these goals.
Asset or Work Unit OEE
Measuring OEE on a single machine can be very valuable. In this case, OEE is simple to apply and can be used to determine which operator achieves the best performance from the asset, or which product is the most efficient to run on the asset. In some cases time of day or environmental conditions have been shown to affect OEE on an asset, a realization that has led to specific assets being run only at night at lower temperatures.
In a work cell consisting of 3-4 machine tools, it is often the goal of OEE to measure how well a single operator or work crew is operating the assets. In this case, the operator is often the bottleneck because without adequate performance information it is difficult to determine how they can use their time efficiently. Measuring and reporting OEE to Operators can help them see the results of their behavior.
Production Line OEE
When assets or work units are configured in a sequential line, the goal of OEE is to identify the bottlenecks that effect the entire line OEE. In this case, OEE is used to ensure that the most expensive/critical asset is always producing. By designing the line around the critical asset, it is possible to achieve a line OEE that is higher than the OEE of the most problematic asset. This can be achieved through the use of accumulation or parallel assets that keep the critical asset producing.
When the same product is manufactured on multiple assets or lines, the ability to view OEE by a specific product can help manufacturing achieve large improvements. A well designed and implemented OEE system will help manufacturers identify why some assets or lines under perform, and take action to improve the OEE.
OEE and Lean Six Sigma Manufacturing
Used correctly, OEE is a key part of making a Lean Six Sigma Manufacturing program more efficient.
Define, Measure, Analyze, Improve, Control (DMAIC). OEE metrics take the DM out of DMAIC, allowing more time to be spent on the AIC portion. Don't use stop watches and expensive consultants to define and measure. Define and measure automatically, all the time.
OEE and ROI
Manufacturing organizations that use OEE to calculate ROI for manufacturing improvements are taking the guesswork out of their calculations. Because they know exactly how productive an asset is, and they know the precise reasons the asset is not productive, they can calculate precisely the improvements that will be gained from improvement investements.
Take a filling line as an example. The filler is the critical asset. The labeling machine is the asset most likely to fail (jam). Experienced filling line design engineers using OEE know exactly how often the labeller will jam, how long it will take to clear the jam, and from this data the size of the accumulation conveyor required to ensure the filler is always filling.
If OEE isn't used to improve or maintain improvement, it becomes cost without a benefit. To get maximum value from OEE three items should be considered:
1. Physical - Is the OEE data available to be collected? Toward Zero is an expert an determining how best to automatically collect and record the data without relying on manual data entry by operators.
3. Fiscal - Can data be collected in a cost effective manner? Spending $50,000 to implement OEE on a packaging line is an expensive proposition. Can the same results be achieved for less? Toward Zero has the experience you need to minimize your investment and maximize your results.
3. Cultural - Does your organization have a continuous improvement culture? Will the metrics be used in a positive light, and drive improvement efforts?