Molten iron is transported from the blast furnace to a
steel furnace, sometimes called a ‘converter’.
At the converter,
molten iron is added to scrap iron / steel which lowers the temperature,
as it acts as an impurity.
A high pressure stream of oxygen and
powdered lime, is blow through the mixture, causing chemical reactions,
removing some of the carbon from the iron. The amount of carbon removed
from the iron determines the quality / grade of steel produced. This part
of the process is monitored very carefully, until the percentage of carbon
is reduced to the correct level, according to the type of steel required.
The waste (called slag) floats to the top and is poured off, before the
molten steel is poured.
The molten steel is poured into moulds,
forming ‘blooms’. It is common for the blooms to be formed into the final
products, by forcing them through a number of rollers. Steel rails for
railways are formed in this way.