Today’s BOFs are large, pear-shaped vessels with an open top used to charge up to 300 tons of hot iron, which gets blasted with oxygen blown in from both top and bottom. The reaction reduces the metal’s carbon content (to as little as 0.04 percent) in about 30 minutes. The combination of a blast furnace and a basic oxygen furnace is the basis of modern integrated steelmaking. Final steps include the transfer of hot steel to continuous casting machines to produce steel slabs, billets (square or rectangular shapes), and strips that are eventually converted into final steel products.
