The Smithville, TN, facility of Shiro-ki North America produces high-strength low-alloy (HSLA) steel parts used in the automotive industry. One such application is the manufacture of seating assemblies and component parts used in motor vehicles. Every year the plant stamps hundreds of thousands of front and rear brackets used in these assemblies. The brackets, stamped out of 590 HSLA, 1.4 to 2.0-mm-thick steel using a progressive die in a 600-ton press, measure 50.8 by 101.6 by 76.2 mm. They undergo a deep draw of 38.1 to 50.8 mm during a tight forming operation. Shiroki-Smithville has been producing the assemblies for five years, and initially, the deep-draw operation resulted in severe tool galling. "We were replacing our forms every three or four months," Ernie Dunkley, tooling assistant general manager, explains. "We also were polishing them after every run. The results were unnecessary rework and sorting. To correct this problem, we implemented several kaizens."
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