Keller
Eliminating an Unnecessary Process
Early in my engineering career, I encountered a recurring reliability problem involving a machine used to turn bitumen sheets before magnetization. Rather than trying to make the machine more reliable, I questioned why the turning operation was necessary in the first place.
The Challenge
The calendering process embossed a gas-evacuation pattern onto the underside of the bitumen sheet. The sheet then had to be turned before entering a magnetizing machine that had been added later to the existing process.
The turning machine had become a reliability issue, and previous efforts had focused on improving the machine itself. This was understandable: the calendering process was an established process that was working correctly and therefore had never been considered part of the problem.
My Approach
I looked upstream and questioned the reason for the turning operation.
The turning was only necessary because the embossed pattern was produced on the wrong side of the sheet for the subsequent magnetization process. I therefore proposed changing the orientation of the calender rolls so that the pattern would be produced on the required side from the outset.
This removed the need to turn the sheet altogether.
What Changed
The turning machine was eliminated from the process.
As a result, its reliability problems disappeared completely — not because the machine had been made more reliable, but because the operation it performed was no longer necessary.
The Lesson
The solution was not to improve the problematic operation. It was to question the assumption that the operation was necessary.