KNOCKING THE POT Slag is a by-product of steel production. As furnaces melt iron ore, scrap metal, limestone, and other elements, impurities separate from the molten metal, forming slag. At some mills, the 2,500-degree F (1,500 C) slag pours directly into enormous pots for transport away from the furnaces. The pots are cast steel. As hot slag hits cool pots, a film forms, allowing the cast steel to radiate the heat of the slag. Pot carriers, like this one from Kress, step in to haul the molten s

KNOCKING THE POT — Slag is a by-product of steel production. As furnaces melt iron ore, scrap metal, limestone, and other elements, impurities separate from the molten metal, forming slag. — At some mills, the 2,500-degree F (1,500 C) slag pours directly into enormous pots for transport away from the furnaces. — The pots are cast steel. As hot slag hits cool pots, a film forms, allowing the cast steel to radiate the heat of the slag. — Pot carriers, like this one from Kress, step in to haul the