Any engineers in the building? (a metalurgy question)?

Question

I need Details for Basic-Oxygen Proccess for steel. How kind of materials are used to make the container? How do they prevent molten steel from pluging the tubes that suply oxygen? Please if you know any details about it it would be great.

Answer 1

The container is usually a refractory lined ladle- like maybe 1/2" or 3/4" thick steel with aluminum oxide bricks or slicon carbide brick. The refractory bricks are usually 18-24" thick and must be replaced regularly- maybe once a month if all goes well.

The air tube is also called a lance. It is largely disposable as they use many of them. The idea is to blow oxygen through the lance at a pressure higher than the molten iron head pressure. (molten iron builds hydrostatic head just like a tank of water- however its almost 8 times higher as 1 foot of water =.43 psi and 1 foot of molten iron is between 3 and 4 psi. 62.4 pounds per cubic foot for water and 490 pounds per cubic foot for iron) Since the molten iron in the ladle is only a couple feet deep, the lance only requires 20-30 psi. By keeping the diameter narrow and the cfm high, the lance receives some cooling benefit- however, it is not uncommon to change them on every batch or start with 10 foot and lose a couple feet on each batch and change them when they get down to 3-4 feet. Remember the largest consumers of steel are steel mills.