Quality Initiatives in Manufacturing: How Do We Handle Incoming Quality Losses Impacting OEE
As organizations embark on Overall Equipment Effectiveness (OEE), I have been particularly impressed with the discussion on Quality Losses and Quality initiatives in manufacturing.
As an example, consider an upstream unit that sends bad quality to a downstream unit that then produces the product as a defective product. The downstream unit can refuse the product and take delays, categorizing the delay as an Idle Downtime loss impacting their availability.
But in some cases, they run the defective material, because of process efficiencies or a lack of inputted key quality characteristics. This now impacts their Quality Loss and not their availability. We will save the quantifying value of these two different buckets another time. But who owns the quality losses in this example, and not necessarily who owns the reasoning of the defect?
Separating this responsibility of process measuring and product measuring is required. OEE requires that the unit that produced the product owns the losses and not the unit that produces the defect. The defect impacts the OEE of the unit that produces the quality losses, it impacts their total effectiveness. It goes through as production then gets removed as a loss in the quality bucket. Consider too that if it goes into the Idle Downtime it impacts their run rate, but if it goes into quality it does not impact their run rate.
Some production units are built to handle and manage these defects because of efficiency purposes or timeliness of recognizing when the defect occurs. Consider saws on downstream units that cut off non-prime material in board-cutting mills or casters in steel-producing industries that produce that are off with the wrong chemistry. In these examples, an upstream unit is impacting the OEE of a downstream unit.
Have you run into this? How did you address it?