Furnace is a museum piece. Shut down in 1970 when it was no longer
profitable for parent company U. S. Pipe, the property was donated to the City
and is maintained as a museum, and a monument to Birmingham's iron
industry. Sloss Furnace today is a fascinating place to visit, and a great
way to gain an understanding of the making of iron that was such a key element
in the development of the Magic City.
This photo, reproduced from the Birmingham Historical
Society's book, Birmingham View, shows the "City
furnace" as it operated from about 1929, when it was completely rebuilt, to
1970 when it closed.
The view is looking to the northwest, across the
mainline tracks of the "railroad reservation". The switch
engine, or shifter, operated by the Sloss, Sheffield, Steel and Iron Railroad (SSS&I)
appears to be switching gondola cars loaded with pig iron bars.
does a blast furnace work? Try this link to the AISI Learning Center
-- several good graphics and lots of text.
In the background of the photo at the top of this page
are the twin blast furnaces with their sloping
charging hoist. The round top towers are known as stoves, and are used
to heat gases that are part of the process. The shed structures at the
left and right are the casting sheds, where workers directed the molten iron
into sand molds laid out on the floor of the shed.
In later years, Sloss operated an automatic casting
machine, which was located outside this view to the right. The molten iron
was transferred to the casting machine in a "bottle" car. This
is an special rail car
with a large container, lined with refractory (special fire brick), so that the
molten metal remains molten for a period of time. The container
("ladle or bottle") could be tipped to pour the molten material out
for the desired purpose. This one, like many of these cars, was
manufactured by the Schnabel Company, and are often called "schnabel
The cars lined up between the locomotive and the
furnace are located on the supply
trestle, where material for the furnace was brought and dropped into
partitioned storage areas below the tracks. (In the photo, the rails of
the supply tracks have been removed, and only the supporting beams remain in
place.) These supply piles were transferred from below ground in a
miniature railway that loaded material from the stock piles and moved it to a
transfer point. Here the skip car for the charging hoist was filled before
traveling to the top to be dumped into the furnace.
In order to understand the process and the layout of
the furnace operation at Sloss, there are interpretive panels at various
locations on the site. Here is a sample, which shows a cross
section of the furnace, the supply trestle, and the hoist.
The material in the furnace became iron and was drawn
off the bottom of the furnace, as was the slag or waste, although the slag came
off the furnace at a higher level than the iron. In many areas these slag
dumps resembled hills of candle drippings, and the dump tracks were extended on
along the piles as they spread out. This material, when cooled could be
used for various things, including coarse aggregate for road building as well as
a soil supplement. At Sloss, the slag piles were located on site.
Here the slag was allowed to cool, and then loaded with steam
shovels, and removed or sold to make other products.
The molten iron would flow in troughs to the sand floor
of the casting shed and the workers would divert the stream to the desired point
in the sand. As the molten iron filled the molds for the bars, lined up in
a row, along the trough, the workers thought that they looked like piglets
suckling a sow. This is understood to be the source of the term "pig
iron". In later years with the bottle car and the automated
continuous casting machine this bit of folklore was lost, but apparently the
The color photo, by the author, shows a view of
Sloss City Furnace looking northeast from the 1st Avenue Viaduct. The
furnace to the right is the western most furnace with its accompanying
"stoves" in the center of the picture. The blower house is
nearly hidden in the center behind the stoves. The black and white photo
is taken from the Library of Congress archives, and was taken by Dorthea Lange,
in June, 1936, from approximately the same location. Obviously the
lens and format are different.
Study the photos carefully and notice that the blast
furnace, casting shed, and sloping skip hoist are the same, for a reference
point. Then, notice the sloping roof, among the stoves, which is the
blower house. The square building on the left is another reference.
Notice that the stoves are different, and there is an enclosure over the pipes
in front of the stoves. Then, notice in the foreground that the concrete
pits in the old photo have been removed. There is a steam shovel in one of
the pits. These are the slag pits, and the shovel was used to move and
load the slag when it had cooled. Today this shovel, or one like it, sits
nearby, on the other side of the central complex.
Additional photos will be added from time to time, as I
have time. Hope you enjoy them. The real fun is coming to
Birmingham, and taking a tour of the furnace complex. Ya'll come, y'hear?
the Sloss Furnace web site
Red Mountain Ore Mine, Sloss.