Steel Dynamics, Inc. (SDI) is the nation’s fifth largest producer of carbon steel products with 2006 annual revenues of $3.2 billion and annual shipments of 4.7 million tons. SDI operates five electric-furnace mini-mills and employs about 3,500. In 2006 about 50 percent of the company's shipments were flat-rolled steel and the remainder was "long products" (bars and beams) and fabricated products. SDI is among the most profitable American steel companies in terms of profit margins and operating ...