Imagine watching an 800-meter race. The athletes start at the sound of the gun. They ramp up in speed hitting their targetted speed on the first straightaway. During their turns, their speeds adjust due to rubbing shoulders, moving lanes, or taking strategic chances to improve their performance. You might even see one athlete slightly slowing down due to a hamstring tightening up. Within this race example, we can add many more influencers of speed. But in manufacturing, what impacts speed? What impacts the performance of producing a product or a service at a specific rate?
Overall Equipment Effectiveness (OEE) is a globally recognized key performance indicator that can be calculated from only four inputs. Once calculated, the insight can steer almost anything towards optimized effectiveness. The four inputs are time, the production of something, delays, and the quality of the production. These four inputs then create the ratios called Availability, Performance, and Quality. The product of these three creates OEE.
Within this majestic calculation, the Performance is often referred to as Speed Loss. It is the effectiveness of producing at a specific rate delay-free. Once someone understands how the Performance is calculated they start to understand the intent of OEE. However, I have often heard what impacts Performance? I believe that you can train individuals to think that there are four things. These categories are product mix, functional failures, product flow, and one last one. We will save that last one until the end.
Performance takes into account Performance Loss, which accounts for anything that causes the manufacturing process to run at less than the maximum possible speed when it is running - OEE.com
The product mix can influence what produces fast and what produces slow. Manufacturers produce products with more processing steps than other ones. A medical lab that produces lab results might have to do an extra step under certain circumstances. A paper mill may have to operate at a slower product rate due to the product’s thickness. Manufacturers could produce material that may have different densities, impacting the volumetric ability to produce a certain amount in a period of time. When asking groups of individuals what impacts the Speed Loss, I have seen this as the most common explanation.
The second most common explanation of Speed Loss is functional failures. Functional failures are influential because the production unit has to slow down to make the product’s quality. An example could be burners in a furnace, whereas 20% are not working as a system. This creates a scenario of the production unit producing slower to allow a modified amount of resistance time in the material to get to a proper temperature. The unit is still producing at a slower pace yet is not delayed.
A function clearly describes what a piece of equipment is intended to do, as well as the level of performance expected to result. Functional failures, on the other hand, detail all the conditions that would prevent a piece of equipment from operating at peak performance. - UpKeep.com
The third most common response is process flow. This is generally around the fluctuating gap times between sequential products being produced or the changes in the speed at the book-ends of a delay. This collection of differences in processing time isn’t being captured by a delay but is instead part of the production process between pieces or between delays. You may also describe this in the form of starting up or shutting down a process in the form of acceleration or deceleration. The OEE of an administration team at a dentist's office that returns from an office hours delay at 8:00 AM may not be at optimum speed yet because the team hasn’t had their second cup of coffee yet.
The last one, one I have referred to as the “Winkenhofer Effect,” sometimes has a diabolic origin of a non-OEE believer. It occurs when a delay trigger is modified or a delay is deleted, resulting in an increased Speed Loss. In this example, the losses exist because a delay does not exist to offset the lack of production. This “Winkenhofer Effect” could be that hollow ingeniousness of an individual that believes they can outsmart OEE by deleting delays to increase Availability. It's true, Availability will increase when delays are deleted or modified. However, the Winkenhofer Effect has a symptom of revelation when the individual that deleted the delays does not see any change in OEE. This individual has to explain the losses within Speed Loss versus Availability Loss. I have often seen that those that experience the Winkenhofer Effect, become your change leaders in the organization when implementing OEE.
Performance is where the magic occurs within the OEE calculation. With a heightened focus on Availability and Quality losses, organizations may lose track of their ability to impact their effectiveness by not focusing on Performance. Understanding what impacts Performance, allows the organization to begin capitalizing on its value.