A manufacturer of automotive torque converters needed to increase quality and reduce scrap in its metal stamping operations. One of the main parts of the converter is produced on a hydraulic stamping press, which created a series of indentations in a metal ring. In the stamping press, hydraulic cylinders force hardened rectangular punches into the metal blank, displacing the metal into a corresponding die. For the torque converter, the tooling creates 136 indentations in each part.

The converters are produced on an automated line that turns out one part every 45 seconds. While efficient, automation poses a risk that many defective parts could be made before a visual inspection by the press operator detected that the indentations weren’t being properly formed because of a worn punch or one that had failed. To make matters worse, the plant runs multiple punching machines simultaneously, so failures sometimes occurred as often as once per shift. This resulted in a great deal of scrap, since faulty parts cannot be reworked.