M8101 - Iron and steel processing

Operational Details
Foundries include iron and steel. The process begins with the design or pattern that is usually made out of wood or plastic. Sand and hardeners are poured over the pattern which hardens to form a mold. Once the mold has been made, the steel or iron is melted in an arc furnace (approximately 2,700 degrees F.), the formed product is then removed by a mechanical ladle, and poured into the mold where it hardens. The mold is then removed and the object buffed to remove any sand. The object is then ground and polished. Products may include: manhole covers, boxcar wheels, pipe valve connectors, tractor and caterpillar gears, bucket teeth, chains, etc.

Usually scrap metal is melted at 2900 degrees F. in a large electric arc oven or furnace, which may hold up to 80 tons. The molten steel is dumped into a large ladle and elevated mechanically to a tower. A lever releases a plug in the bottom of the ladle and the molten steel is poured into another receptacle called a Tundish, that has two holes in the bottom. As the steel flows out of the two holes it follows two channels, approximately 4" wide and deep, almost straight down, then bending to horizontal at the bottom and flowing along a conveyor system.

The steel cools on the way down and is further cooled by water, and cut into 8' lengths by an automatic acetylene cutter at the end of the conveyor. The resulting steel is stockpiled for shipment.

Should the employer also have a rolling mill, the steel billets or sheets are reheated in electric ovens, after which the steel goes through a series of rollers to gradually reduce the thickness and it also lengthens the steel so it can be used for reinforcing rod. If angle iron is to be produced, the steel is pushed through a mold as a last step. The steel is tempered by spraying water onto the steel. After going through a cooling bed, the steel is cut to length. If steel balls are manufactured, rod is cut up to a 2" thickness, and the pieces are fed into a press that forms it into a perfect ball.

SIC Codes
000000578 - Iron and steel processing