Next come the tilting open-hearth furnaces, where the iron is subjected
to the action of lime at a very high temperature. This removes the
phosphorus and leaves a bath of commercially pure iron which is then
"teemed" into a hundred-ton ladle, wherein it is treated in such a way
as to give it the properties required in the finished steel. What these
properties may be, depends, of course, upon the purpose to which the
steel is to be put. Rails, for example, must, above all, resist
abrasion, and consequently have a higher carbon content than, say,
reinforcing bars for concrete work. To obtain various qualities in steel
are added carbon, ferro-manganese, or ferro-silicon in proportions
differing according to requirements.
In the next process steel ingots are made. I lost track of the exact
detail of this, but I remember seeing the ingots riding about in their
own steel cars, turning to an orange color as they cooled, and I
remember seeing them pounded by a hammer that stood up in the air like
an elevated railroad station, and I know that pretty soon they got into
the blooming mill and were rolled out into "blooms," after which they
were handled by a huge contrivance like a thumb and forefinger of steel
which--though the blooms weigh five tons apiece--picked them up much as
you might pick up a stick of red candy.
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