Bessemer process

Bessemer process
a process of producing steel, in which impurities are removed by forcing a blast of air through molten iron.
[1855-60; after H. BESSEMER]

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Technique for converting pig iron to steel invented by Henry Bessemer in England in 1856 and brought by him into commercial production in 1860.

Air blown through liquid pig iron in a refractory-lined converter oxidizes the carbon and silicon in the iron. Heat released by the oxidation keeps the metal molten. R.F. Mushet contributed the technique for deoxidizing the converted metal that made the process a success. William Kelly conducted experiments with an air-blown converter between 1856 and 1860 in Kentucky and Pennsylvania, but failed to make steel. Alexander L. Holley built the first successful Bessemer steel plant in the U.S. in 1865. High-volume production of low-cost steel in Britain and the U.S. by the Bessemer process soon revolutionized building construction and provided steel to replace iron in railroad rails and many other uses. The Bessemer process was eventually superseded by the open-hearth process. See also basic Bessemer process.

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      the first method discovered for mass-producing steel. Though named after Sir Henry Bessemer (Bessemer, Sir Henry) of England, the process evolved from the contributions of many investigators before it could be used on a broad commercial basis. It was apparently conceived independently and almost concurrently by Bessemer and by William Kelly (Kelly, William) of the United States. As early as 1847, Kelly, a businessman-scientist of Pittsburgh, Pa., began experiments aimed at developing a revolutionary means of removing impurities from pig iron by an air blast; Kelly theorized that not only would the air, injected into the molten iron, supply oxygen to react with the impurities, converting them into oxides separable as slag, but that the heat evolved in these reactions would increase the temperature of the mass, keeping it from solidifying during the operation. After several failures, he succeeded in proving his theory and rapidly producing steel ingots.

      In 1856 Bessemer, working independently in Sheffield, developed and patented the same process. Whereas Kelly had been unable to perfect the process owing to a lack of financial resources, Bessemer was able to develop it into a commercial success. Another Englishman, Robert Forester Mushet, found that adding an alloy of carbon, manganese, and iron after the air-blowing was complete restored the carbon content of the steel while neutralizing the effect of remaining impurities, notably sulfur. A Swedish ironmaster, Goran Goransson, redesigned the Bessemer furnace, or converter, making it reliable in performance. The end result was a means of mass-producing steel. The resultant volume of low-cost steel in Britain and the United States soon revolutionized building construction and provided steel to replace iron in railroad rails and many other uses.

      The Bessemer converter is a cylindrical steel pot approximately 6 m (20 feet) high, originally lined with a siliceous refractory. Air is blown in through openings (tuyeres) near the bottom, creating oxides of silicon and manganese, which become part of the slag, and of carbon, which are carried out in the stream of air. Within a few minutes an ingot of steel can be produced, ready for the forge or rolling mill.

      The original Bessemer converter was not effective in removing the phosphorus present in sizable amounts in most British and European iron ore. The invention in England, by Sidney Gilchrist Thomas, of what is now called the Thomas-Gilchrist converter, which was lined with a basic material such as burned limestone rather than an (acid) siliceous material, overcame this problem. Another drawback to Bessemer steel, its retention of a small percentage of nitrogen from the air blow, was not corrected until the 1950s. The open-hearth process, which was developed in the 1860s, did not suffer from this difficulty, and it eventually outstripped the Bessemer process to become the dominant steelmaking process until the mid-20th century. The open-hearth process was in turn replaced by the basic oxygen process, which is actually an extension and refinement of the Bessemer process.

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Universalium. 2010.

Look at other dictionaries:

  • Bessemer process — [bes′ə mər] n. [after Sir Henry Bessemer (1813 98), Eng engineer who developed it] a method of making steel by blasting air through molten pig iron in a large container (Bessemer converter) to burn away the carbon and other impurities …   English World dictionary

  • Bessemer process — Bessemer process. См. Бессемеровский процесс. (Источник: «Металлы и сплавы. Справочник.» Под редакцией Ю.П. Солнцева; НПО Профессионал , НПО Мир и семья ; Санкт Петербург, 2003 г.) …   Словарь металлургических терминов

  • Bessemer process — The Bessemer process was the first inexpensive industrial process for the mass production of steel from molten pig iron. The process is named after its inventor, Henry Bessemer, who took out a patent on the process in 1855. The process was… …   Wikipedia

  • bessemer process — process of producing steel from impure iron by forcing compressed air through molten metal …   English contemporary dictionary

  • Bessemer process — noun a steel making process, now largely superseded, in which carbon, silicon, and other impurities are removed from molten pig iron by oxidation in a blast of air in a special tilting retort (a Bessemer converter). Origin C19: named after the… …   English new terms dictionary

  • Bessemer process — noun Etymology: Sir Henry Bessemer Date: 1856 a process of making steel from pig iron by burning out carbon and other impurities by means of a blast of air forced through the molten metal …   New Collegiate Dictionary

  • Bessemer process — /ˈbɛsəmə ˌproʊsɛs/ (say besuhmuh .prohses) noun a process of producing steel, in which impurities are removed by forcing a blast of air through molten iron. {See Bessemer converter} …   Australian English dictionary

  • BESSEMER PROCESS —    See BESSEMER, SIR HENRY …   The Nuttall Encyclopaedia

  • Bessemer process —  Steelmaking method named after Sir Henry Bessemer (1813–1898), British metallurgist …   Bryson’s dictionary for writers and editors

  • Bessemer process — Bes′semer proc ess n. mel a process of producing steel in which impurities are removed by forcing air through molten iron in a refractory lined metal container(Bes′semer convert er) …   From formal English to slang