The Timken Co. collaborated with one of its major automotive customer to produce a steel that is easier to machine. Working with the Robert Bosch Corp., Timken engineers developed a hot-rolled temper process to produce steel that Bosch could more readily machine for a diesel fuel injector on truck engines. According to Timken’s press release, Bosch, a manufacturer of automotive and industrial technology, previously used a low alloy steel that was hot rolled annealed at its plant in Charleston, SC. The process produced steel with a high surface-to-core hardness gradient that was difficult for Bosch to machine. Excessive metal buildup on tool edges ultimately led to reduced drill and tool life. In 2005, Timken suggested a hot rolled temper process, which would be used to produce steel that would machine more efficiently and respond more effectively during Bosch’s heat treatment process. The hot rolled process would produce tempered steel with a higher hardness and significantly reduce the temperature required for heat treatment. After conducting the machining trials and component testing, Bosch confirmed the improved machinability of the steel utilizing the Timken process. "The high pressure pulsation fatigue life of the hot rolled tempered steel improved notably over that of the hot rolled annealed steel," says Wilt Staples, senior purchasing engineer at the Bosch Charleston plant.