ABSTRACT
Iron is the cheapest and most widely used metal. Its annual production exceeds by far that of all other metals combined. It comprises approximately 93% of the tonnage of all the metals used. Most pig iron is transferred in molten state to steelmaking plants and in this form it is referred to as hot metal. Steel is the most important commerical form of iron because of its high tensile strength. Molten pig iron from the blast furnace is usually stored in a hot-metal mixer before transferring it to the steelmaking plant. Iron ores are the most important raw material charged to blast furnace. Other minor material are the following: Mill scale, blast furnace flue dust after sintering and open hearth slag. Pig iron is transferred molten as hot metal or molded in pig-machine. The hearth temperature influences the C-content in pig iron.
