
115Understanding Potroom Processes
The new element in the chart now was the introduction of some specic
control points that he could test the processes against each day, and which
would provide feedback to the owners of each process through trends or
reduced variation over time. For sure, some of them were not where they
should be. For example the percentage of anode butts with thimbles exposed
was running as high as 30% on some days in the rodding room. This was just
by Rob’s eyeball as he walked along the power and free conveyer carrying
the cleaned anode butts. It wasn’t even a measure the plant collected at the
moment, and neither was red ...