Bessemer Process
:
STEEL MAKING
:
The Working Of Steel
The bessemer process consists of charging molten pig iron into
a huge, brick-lined pot called the bessemer converter, and then
in blowing a current of air through holes in the bottom of the
vessel into the liquid metal.
The air blast burns the white hot metal, and the temperature increases.
The action is exactly similar to what happens in a fire box under
forced draft. And in both cases some parts of the
aterial burn
easier and more quickly than others. Thus it is that some of the
impurities in the pig iron--including the carbon--burn first, and
if the blast is shut off when they are gone but little of the iron
is destroyed. Unfortunately sulphur, one of the most dangerous
impurities, is not expelled in the process.
A bessemer converter is shown in Fig. 1, while Fig. 2 shows the
details of its construction. This shows how the air blast is forced
in from one side, through the trunnion, and up through the metal.
Where the steel is finished the converter is tilted, or swung on
its trunnions, the blast turned off, and the steel poured out of
the top.