Evening star., 1919-09-28
TAKES Up PHASES
OF STEEL INDUSTRY
Furnaces and Production
Methods Described by
/, Geographic Society.

Because Of the wide interest in the
strike of steel workers. the National
Geographic Society has issued two
bulletins on the steel industry. The
first dealt with Bessemer steel, and
the second one. based on communi-
cation to the society, describes other
production methods. as follows:
IAN open-hearth furnace looks a
good deal like an ordinary bake oven.
but when one looks in through the
water-cooled door a vast difference
appears. Instead Of pans of fragrant
fat loaves of baking bread, there Is
an imposing pool of fiery liquid as
bright as the filament Of high-power
tungsten lamp, so dazzling that 1t can
be examined with safety to: the eyes
only by those using colored glasses.
Tinted here and there with streaks
of soft blue and dainty pink, 1t looks
like melted stick candy.
Preparation of Battery.
"In preparing battery of open
: hearth furnaces for charge ninety
ground dolomite is shoveled In hrst:
This melts like glass and fills up all
cracks and crannies caused by the pow
erful heat of the preceding charge.
Then a little train rolls up before the
battery and an electric crane dumps
box after box of scrap metal from rne
cars into the furnaces. ON some dls-
tance is a great steel tank lined with
fire brick and full of liquid pig metal
''When the scrap has melted and the
contents of the caldron are cooked
enough, when the impurities have been
driven out and tolled away, the merry
broth is seasoned as it were, with
the proper amount of carbon, spiegel.
ferromanganese, tungsten. ferroSihcon.
vanadium, or whatever Is necessary to
give the desired character to the re-
sulting steel
"Then comes the tapping of the fur
mace. An electric crane lifts a great
ladle into position. a workman jams
crowbar through a clay-plugged mole
at the base, and out flows the frenzied
stream into the ladle. The Stag rises
flows. congealing on the outside. Of
the ladle. Then the big crane picks
up the ladle. swings 1t over to the
pouring platform, where 1t. in Its
turn, is tapped and it's purified fluid
run on into molds.
ding these ladies. for the presence OF
q few drops Of moisture when the hot
metal is poured into one might cause
an explosion and loss of life Just be-
fore they receive the molten metal the
ladies are heated nearly white hot, in
II
chill In them.
"As fast as they are filled the ladies
are swung out over the ingot molds
and the liquid steel is run into them
and allowed to cool and take its solid
form. 1t is as il water were poured
into molds and set in a refrigerating
machine to freeze into blocks of ice.
The only difference fs that the freez-
Ing point Of steel Is away above the
boiling point of water.
Other Types of Furnaces. {
There are two other important
types of steel furnaces-the crucible
furnace and the electric furnace. In
both of them the idea is to keep all
and to regulate the addition of alloys
and oxygen destroyers to a nicely. In
. crucible furnace the metal Is placed
IN graphite clay pots, covers are put
over them. and the pots subjected to
great heat Silica is gradually abb
sorbed out of the clay in the pots and
transformed into silicon by coming
into contact with the carbon in the
steel The silicon in its turn absorbs
the oxygen and thus Quiets the froth-
ing. foamiug contents Of the kettle.
"The electric furnace acts in much
that there Is no necessity Of putting
the steel in covered potSsto keep out
gases and other impurities.
< An electric arc, established between
huge electrodes and the surface Of the
Stag. produces the heat in such a
furnace. By varying the materials
used in the formation Of the Stag any
impurity can be wooed OF and the
glowing steel left as pure as crystal.
The alloys are then mixed with the
steel and 1t is made fit for any use
desired. It is drawn OF into ladies'
and poured into ingot molds. where
it hardens. ready to be worked up into
those things that constitute the last
word in fine steel"