InventorsHenry
Bessemer - The Steel Man Englishmen, Sir Henry Bessemer
(1813-1898)
invented the first process for mass-producing steel inexpensively,
essential to the development of skyscrapers.
An American, William Kelly, had held a patent for "a system of air blowing
the carbon out of pig iron" a method of steel production known as the pneumatic
process of steelmaking. Air is blown through molten pig iron to oxidize
and remove unwanted impurities.
Bankruptcy forced Kelly to sell his
patent to Bessemer, who had been working on a similar process for making
steel. Bessemer patented "a decarbonization process, utilizing a blast
of air" in 1855.
Modern steel is made using technology
based on Bessemer's process. Bessemer was knighted in 1879 for his contribution
to science. The "Bessemer Process" for mass-producing steel, was named
after Bessemer.
The inventor, Sir Henry Bessemer
on the making of the first steel ingot:
I well remember how anxiously
I awaited the blowing of the first 7-cwt. charge of pig iron. I had engaged
an ironfounder's furnace attendant to manage the cupola and the melting
of the charge. When his metal was nearly all melted, he came to me, and
said hurriedly: "Where be going to put the metal, maister?" I said: "I
want you to run it by a gutter into that little furnace," pointing to the
converter, "from which you have just raked out all the fuel, and then I
shall blow cold air through it to make it hot." The man looked at me in
a way in which surprise and pity for my ignorance seemed curiously blended,
as he said: "It will soon be all of a lump." Notwithstanding this prediction,
the metal was run in, and I awaited with much impatience the result. The
first element attacked by the atmospheric oxygen is the silicon, generally
present in pig iron to the extent of 1 1/2 to 2 per cent.; it is the white
metallic substance of which flint is the acid silicate. Its combustion
furnishes a great deal of heat; but it is very undemonstrative, a few sparks
and hot gases only indicating the fact that something is going quietly
on. But after an interval of ten or twelve minutes, when the carbon contained
in grey pig iron to the extent of about 3 per cent. is seized on by the
oxygen, a voluminous white flame is produced, which rushes out of the openings
provided for its escape from the upper chamber, and brilliantly illuminates
the whole space around. This chamber proved a perfect cure for the rush
of slags and metal from the upper central opening of the first converter.
I watched with some anxiety for the expected cessation of the flame as
the carbon gradually burnt out. It took place almost suddenly, and thus
indicated the entire decarburisation of the metal. The furnace was then
tapped, when out rushed a limpid stream of incandescent malleable iron,
almost too brilliant for the eye to rest upon; it was allowed to flow vertically
into the parallel undivided ingot mould. Then came the question, would
the ingot shrink enough, and the cold iron mould expand enough, to allow
the ingot to be pushed out? An interval of eight or ten minutes was allowed,
and then, on the application of hydraulic force to the ram, the ingot rose
entirely out of the mould, and stood there ready for removal.
Henry
Bessemer English inventor and engineer, who
invented the first process for mass-producing steel inexpensively.
Henry
Bessemer, Man of Steel Short biography on Henry Bessemer's
invention of steel production.
Sir
Henry Bessemer, F.R.S. Full length online autobiography
written by Bessemer - full of illustrations of steel production.
A
Retrospective of Twentieth-Century Steel Replacing open hearths with basic
oxygen furnaces boosted steel mill productivity more than any other single
change steelmakers made in the twentieth century.
More on Steel Robert Mushet invented tungsten
steel in 1868.
Henry Brearly invented stainless
steel in 1916.
