Case Study: Bridgestone achieves faster tire certification and higher production with Minitab

Bridgestone Costa Rica Getting a Grip with Design of Experiments

Bridgestone Costa Rica, part of Bridgestone Corporation, needed to increase plant capacity while also certifying a new light truck tire to meet U.S. Department of Transportation standards. The plant’s ribbon-tread machine was underused, but tires made with it were failing key certification tests, creating a bottleneck in production. To tackle the issue, Bridgestone used Minitab Statistical Software.

Using Minitab, the team ran measurement system analysis, process capability studies, regression analysis, a 2-level factorial design of experiments, and response optimization to identify the key process factors and set optimal input values for the ribbon-tread process. The new model reduced out-of-spec output from 97.29% to 0.9%, improved certification performance, and enabled the plant to qualify tires faster and expand use of the process to other tire sizes. Bridgestone reported initial savings of $74,200 and about $2.5 million in opportunity costs, with the new process helping increase overall production.

BridgeStone

Kenneth Quirós Acuña

Six Sigma Black Belt