Bessemer process | metallurgy | Britannica.com Bessemer process Sir Henry Bessemer Bessemer process, the first method discovered for mass-producing steel . Though named after Sir Henry Bessemer 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 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. Bessemer furnace, Kelham Island Museum, Sheffield, England. Wikityke 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.

Similar Topics Sir Henry Bessemer | English inventor and engineer | Britannica.com English inventor and engineer William George Armstrong, Baron Armstrong Sir Henry Bessemer, (born Jan. 19, 1813, Charlton, Hertfordshire , Eng.—died March 15, 1898, London ), inventor and engineer who developed the first process for manufacturing steel inexpensively (1856), leading to the development of the Bessemer converter. He was knighted in 1879. Bessemer, detail of an oil painting by Rudolf Lehmann; in the Iron and Steel Institute, London Courtesy of The Iron and Steel Institute, London; photograph, The Science Museum, London Bessemer was the son of an engineer and typefounder. He early showed considerable mechanical skill and inventive powers. After the invention of movable stamps for dating deeds and other government documents and the improvement of a typesetting machine, he went to the manufacture of “gold” powder from brass for use in paints. The florid decoration of the time demanded great quantities of such material, and Bessemer’s secret process soon brought him great wealth.

He developed other inventions, notably sugarcane-crushing machinery of advanced design, but he was soon devoted to metallurgy. In his time there were but two iron-based construction materials: cast iron made by the treatment of iron ore with coke in the blast furnace and wrought iron made from cast iron in primitive furnaces by the laborious manual process of “puddling” (stirring the melted iron to remove carbon and raking off the slag). Cast iron was excellent for load-bearing purposes, such as columns or bridge piers, and for engine parts, but for girders and other spans, and particularly for rails, only wrought iron was suitable. Puddling removed carbon, which makes cast iron brittle, and produced a material that could be rolled or forged, but only in “blooms,” or large lumps of 100–200 pounds, and that was full of slag. The blooms had to be laboriously forged together by steam hammers before they could be rolled to any useful length or shape. The only material known as steel was made by adding carbon to pure forms of wrought iron, also by slow and discontinuous methods; the material was hard, would take an edge, and was used almost entirely for cutting tools.

During the Crimean War , Bessemer invented an elongated artillery shell that was rotated by the powder gases. The French authorities with whom he was negotiating, however, pointed out that their cast-iron cannon would not be strong enough for this kind of shell. He thereupon attempted to produce a stronger cast iron. In his experiments he discovered that the excess oxygen in the hot gases of his furnace appeared to have removed the carbon from the iron pigs that were being preheated—much as the carbon is removed in a puddling furnace—leaving a skin of pure iron. Bessemer then found that blowing air through melted cast iron not only purified the iron but also heated it further, allowing the purified iron to be easily poured. This heating effect is caused by the reaction of oxygen with the carbon and silicon in the iron. Utilizing these new techniques, which later became known as the Bessemer process , he was soon able to produce large, slag-free ingots as workable as any wrought-iron bloom, and far larger; he invented the tilting converter into which molten pig iron could be poured before air was blown in from below.

Eventually, with the aid of an iron-manganese alloy, which was developed at that time by Robert Forester Mushet , Bessemer also found how to remove excess oxygen from the decarburized iron. Britannica Stories Ringling Bros. Folds Its Tent His announcement of the process in 1856 before the British Association for the Advancement of Science in Cheltenham, Gloucestershire, brought many ironmasters to his door, and many licenses were granted. Very soon, however, it became clear that two elements harmful to iron, phosphorus and sulfur, were not removed by the process—or at least not by the fireclay lining of Bessemer’s converter . It was not until about 1877 that the British metallurgist Sidney Gilchrist Thomas developed a lining that removed phosphorus and made possible the use of phosphoric ores of the Continent. Technological Ingenuity Bessemer had, unknown to himself, been using phosphorus-free iron, but the ironmasters were not so lucky. Their iron was perfectly satisfactory for the puddling process, in which phosphorus is removed because the temperatures are lower, but it could not be used in the Bessemer process.

Bessemer was forced to call in his licenses and find a phosphorus-free source of iron in northwestern England; thus he was able to enter the steel market on his own. Once the phosphorus problem was recognized and solved, he became a licensor once again, and vast profits flowed in. It became clear that “mild steel”—as it was known to distinguish it from the hard tool steels—could more clearly and reliably be used in place of wrought iron for ship plate, girders, sheet, rods, wire, rivets, and other items. The invention of the open-hearth (Siemens-Martin) process in the late 1860s eventually outstripped that of the Bessemer process. This has now yielded place, in great measure, to oxygen steelmaking, which is a further development and refinement of the Bessemer process. In his later years—the process had not become a clear success until he was nearing 70—Bessemer continued to invent and make discoveries. The solar furnace he built was more than a successful toy; he designed and built an astronomical telescope for his own amusement; and he developed a set of machines for polishing diamonds that helped to reestablish that trade in London.

Apart from his knighthood , he received many honours, such as the Fellowship of the Royal Society . Bessemer’s An Autobiography (1905), with a concluding chapter by his son, Henry Bessemer, is the only comprehensive biography and the source of most material written about him since. Making the Modern World - New science, new materials, new power New science, new materials, new power New steel: The Bessemer converter The earliest evidence of steel production is from sub-Saharan Africa in the first millennium BC. The Haya people, from an area now in north western Tanzania, developed a technology for producing high-grade carbon steel that was in use until the 1950s. The Hayas used a cone-shaped clay kiln to heat the iron ore, which was pre-roasted to increase its carbon content. Air was pumped into the base of the kiln, passing through the furnace through clay pipes, before arriving inside the kiln. This preheated air allowed very high temperatures to be achieved inside the kiln, improving fuel efficiency as well as the quality of the iron.

In Europe before Henry Bessemer invented his Converter in 1856, steel had been an expensive, high-quality metal made by artisans. It was used mainly for tools and weapons while engineers generally preferred wrought and cast iron. The Bessemer Converter had a huge impact on the use of steel. Its cheap, easily produced, medium-quality steel quickly replaced iron for all large-scale engineering work and transformed both industry and society in © Science Museum/Science & Society Picture Library Europe and the United States. When cheap steel products were imported into Africa in the early twentieth century, it also spelled the end of the Hayas' steel industry. © Science Museum/Science & Society Picture Library The Bessemer method converts molten pig iron into steel in a squat, egg-shaped bowl. Blasts of cold air are blown through the liquid metal via perforations in the bowl's base. The air burns off excess carbon and other impurities. When the iron is nearly purified, more carbon might be added. Finally the bowl is tilted down and the newly made steel poured into a ladle ready to cast into ingot moulds. The Bessemer process was simple but the visual effect was extraordinary.

In 1893, an over-excited journalist at McClure's Magazine wrote: A fountain of sparks arose, gorgeous as ten thousand rockets, and fell with a beautiful curve, like the petals of some enormous flower…. Down came the vessel, until out of it streamed the smooth flow of terribly beautiful molten metal. In America the introduction of the Bessemer Converter had an enormous impact on an expanding society. The availability of cheap, durable steel rails allowed pioneers to build over 30,000 miles of railroad and colonise the western part of the country. © Science Museum/Science & Society Picture Library The early period of this expansion was satisfied by Britain's steel railmakers, particularly those in Sheffield, which remained the centre of the trade until 1870. The steel industry, along with coal, textiles and iron, had enabled Britain to build its Empire. But by the end of the nineteenth century the industry was strongest in the United States, whose steel producers increased efficiency and dropped prices. As well as railways, the Bessemer Converter was instrumental in the production of armaments. Guns, cannons and warships became relatively inexpensive to produce, boosting America's military power.

After 1900 the Bessemer process was rapidly replaced by an alternative method, the Siemens-Martin or open hearth process. This allowed precise control of temperatures resulting in better quality steel. © Science Museum/Science & Society Picture Library Steel frames were used to build towering skyscrapers as the rural population moved to the booming American cities. New sheet steel led to the development of myriad consumer products including washing machines, electric ovens, refrigerators and, perhaps most importantly of all, the automobile. By 1914 automobile manufacturers had become the leading consumers of steel. The last Bessemer Converter in North America went out of commission in the 1960s. Resource Descriptions The squat, egg-shaped Bessemer Converter seemed an unlikely candidate to lead a revolution in manufacturing. Sir Henry Bessemer. Ingot of Bessemer steel. Steel is an alloy of iron, carbon and small amounts of other elements. Iron contains impurities in the form of silicon, phosphorus, sulphur and manganese; the production of steel involves the removal of these impurities (known as slag) and the addition of desirable alloying elements. Manufacturing Bessemer steel.

Inventor Henry Bessemer Biography American Steel, Built to Last DVD / 1 Volume Set / 50 Minutes / History Channel / Less than $25.00 / Also VHS Its roots go back to the Ancient Egyptians, whose iron weapons helped maintain an empire that lasted three millennia. But in the 1850s, Englishmen Henry Bessemer invented a process that turned iron into steel, and the world was changed forever. It became the foundation of the corporate empires of Carnegie and Morgan; skyscrapers with skeletons of steel scraped the heavens; steel rails, trains, ships, planes, and automobiles built a transportation network unmatched in the world. Sir Henry Bessemer Autobiography It is an interesting fact that the statistics published by the Annales des Mines for 1893 shows that it would take more than three years' production of all the gold mines in the world to pay in gold for one year's production of Bessemer steel. HTML version produced by Eric Hutton . Bessemer Patents Henry Bessemer was a prolific inventor. See a complete listing of the patents issued to him.

It will be noticed that the patents chiefly refer to four main subjects: The manufacture of glass, the manufacture of iron and steel, improvements in ordnance, and the manufacture of sugar. WORDS OF WISDOM: "I had an immense advantage over many others dealing with the problem inasmuch as I had no fixed ideas derived from long-established practice to control and bias my mind, and did not suffer from the general belief that whatever is, is right." - Sir Henry Bessemer Bessemer Process The principle involved is that of oxidation of the impurities in the iron by the oxygen of air that is blown through the molten iron; the heat of oxidation raises the temperature of the mass and keeps it molten during operation. Short History of Steel: From Iron to Bessemer & Beyond By Terence Bell Updated November 20, 2016 How did steelmaking evolve from its roots in making iron? Let's take a look at the history of steel. The Era of Iron At very high temperatures, iron begins to absorb carbon, which lowers the melting point of the metal, resulting in cast iron (2.5 to 4.5% carbon).

The development of blast furnaces, first used by the Chinese in the 6th century BC but more widely used in Europe during the Middle Ages, increased the production of cast iron. Pig Iron Molten iron that was run out of the blast furnaces and cooled in a main channel and adjoining molds became referred to as pig iron because the large, central and adjoining smaller ingots resembled a sow and suckling piglets. Cast Iron Cast iron is strong but suffers from brittleness due to its carbon content, making it less than ideal for working and shaping. As metallurgists became aware that the high carbon content in iron was central to the problem of brittleness, they experimented with new methods for reducing the carbon content in order to make iron more workable. Wrought Iron By the late 18th century, ironmakers learned how to transform cast pig iron into a low-carbon content wrought iron using puddling furnaces (developed by Henry Cort in 1784). The furnaces heated molten iron, which had to be stirred by puddlers using long oar-shaped tools, allowing oxygen to combine with and slowly remove carbon.

As the carbon content decreases, iron's melting point increases, so masses of iron would agglomerate in the furnace. These masses would be removed and worked with a forge hammer by the puddler before being rolled into sheets or rails. By 1860, there were over 3000 puddling furnaces in Britain, but the process remained hindered by its labor and fuel intensiveness. Blister Steel One of the earliest forms of steel, blister steel, began production in Germany and England in the 17th century and was produced by increasing the carbon content in molten pig iron using a process known as cementation. In this process, bars of wrought iron were layered with powdered charcoal in stone boxes and heated. After about a week, the iron would absorb the carbon in the charcoal. Repeated heating would distribute carbon more evenly and the result, after cooling, was blister steel. The higher carbon content made blister steel much more workable than pig iron, allowing it to be pressed or rolled.

Blister steel production advanced in the 1740s when English clockmaker Benjamin Huntsman while trying to develop a high-quality steel for his clock springs, found that the metal could be melted in clay crucibles and refined with a special flux to remove slag that the cementation process left behind. The result was crucible—or cast—steel. But due to the cost of production, both blister and cast steel was only ever used in specialty applications. As a result, cast iron made in puddling furnaces remained the primary structural metal in industrializing Britain during most of the 19th century. The Bessemer Process and Modern Steelmaking The growth of railroads during the 19th century in both Europe and America put great pressure on the iron industry, which still struggled with inefficient production processes. Steel was still unproven as a structural metal and production was slow and costly. That was until 1856 when Henry Bessemer came up with a more effective way to introduce oxygen into molten iron to reduce the carbon content.

Now known as the Bessemer Process, Bessemer designed a pear-shaped receptacle—referred to as a 'converter'—in which iron could be heated while oxygen could be blown through the molten metal. As oxygen passed through the molten metal, it would react with the carbon, releasing carbon dioxide and producing a more pure iron. The process was fast and inexpensive, removing carbon and silicon from iron in a matter of minutes but suffered from being too successful. Too much carbon was removed and too much oxygen remained in the final product. Bessemer ultimately had to repay his investors until he could find a method to increase the carbon content and remove the unwanted oxygen. At about the same time, British metallurgist Robert Mushet acquired and began testing a compound of iron, carbon, and manganese —known as spiegeleisen . Manganese was known to remove oxygen from molten iron and the carbon content in the spiegeleisen if added in the right quantities, would provide the solution to Bessemer's problems. Bessemer began adding it to his conversion process with great success. One problem remained.

Bessemer had failed to find a way to remove phosphorus—a deleterious impurity that makes steel brittle—from his end product. Consequently, only phosphorus-free ores from Sweden and Wales could be used. In 1876 Welshman Sidney Gilchrist Thomas came up with the solution by adding a chemically basic flux—limestone—to the Bessemer process. The limestone drew phosphorus from the pig iron into the slag, allowing the unwanted element to be removed. This innovation meant that, finally, iron ore from anywhere in the world could be used to make steel. Not surprisingly, steel production costs began decreasing significantly. Prices for steel rail dropped more than 80% between 1867 and 1884, as a result of the new steel producing techniques, initiating growth of the world steel industry. The Open Hearth Process: In the 1860s, German engineer Karl Wilhelm Siemens further enhanced steel production through his creation of the open hearth process. The open hearth process produced steel from pig iron in large shallow furnaces. Using high temperatures to burn off excess carbon and other impurities, the process relied on heated brick chambers below the hearth.

Regenerative furnaces later used exhaust gasses from the furnace to maintain high temperatures in the brick chambers below. This method allowed for the production of much larger quantities (50-100 metric tons could be produced in one furnace), periodic testing of the molten steel so that it could be made to meet particular specifications and the use of scrap steel as a raw material. Although the process itself was much slower, by 1900 the open hearth process had largely replaced the Bessemer process. Birth of the Steel Industry: The revolution in steel production that provided cheaper, higher quality material, was recognized by many businessmen of the day as an investment opportunity. Capitalists of the late 19th century, including Andrew Carnegie and Charles Schwab, invested and made millions (billions in the case of Carnegie) in the steel industry. Carnegie's US Steel Corporation, founded in 1901, was the first corporation ever launched valued at over one billion dollars. Electric Arc Furnace Steelmaking: Just after the turn of the century, another development occurred that would have a strong influence on the evolution of steel production.

Paul Heroult's electric arc furnace (EAF) was designed to pass an electric current through charged material, resulting in exothermic oxidation and temperatures up to 3272°F (1800°C), more than sufficient to heat steel production. Initially used for specialty steels, EAFs grew in use and, by World War II, were being used for the manufacturing of steel alloys. The low investment cost involved in setting up EAF mills allowed them to compete with the major US producers like US Steel Corp. and Bethlehem Steel, especially in carbon steels, or long products. Because EAFs can produce steel from 100% scrap—or cold ferrous—feed, less energy per unit of production is needed. As opposed to basic oxygen hearths, operations can also be stopped and started with little associated cost. For these reasons, production via EAFs has been steadily increasing for over 50 years and now accounts for about 33% of global steel production. Oxygen Steelmaking: The majority of global steel production—about 66%—is now produced in basic oxygen facilities.

The development of a method to separate oxygen from nitrogen on an industrial scale in the 1960s allowed for major advances in the development of basic oxygen furnaces. Basic oxygen furnaces blow oxygen into large quantities of molten iron and scrap steel and can complete a charge much more quickly than open hearth methods. Large vessels holding up to 350 metric tons of iron can complete conversion to steel in less than one hour. The cost efficiencies of oxygen steelmaking made open-hearth factories uncompetitive and, following the advent of oxygen steelmaking in the 1960s, open-hearth operations began closing. The last open-hearth facility in the US closed in 1992 and in China in 2001. Sources: Making the Modern World - Sir Henry Bessemer Sir Henry Bessemer Born: 19 January 1813, Charlton, Hertfordshire, England Died: 15 March 1898, London, England Inventor of the first process for mass-producing steel. Bessemer demonstrated considerable mechanical skill and inventiveness early in life. His first major success was in the manufacture of cheap 'gold' paint made with bronze powder.

Bessemer's paint was widely used to adorn gilded decoration and brought him great wealth. In 1854, during the Crimean War, Bessemer invented a new type of artillery shell. The cast-iron guns of the time could not deal with the forces of the more powerful shell. Bessemer realised that steel, a stronger material, would serve better, but it was prohibitively expensive and could only be produced in small batches. Thus, in 1856 he produced the first Bessemer Converter. This new technology allowed the production of steel at lower prices and in large quantities. The availability of cheap, plentiful steel had an enormous impact on industry and society as a whole. Bessemer received a knighthood and became a Fellow of the Royal Society. Although the Bessemer Converter is no longer used, modern steel is made using technology based on Bessemer's process. Bessemer Converter | Sheffield Industrial Museums Trust Bessemer Converter Kelham Island Museum The Bessemer Converter is one of only three converters left in the world.

It was used by the British Steel Corporation in Workington until 1975(4?) and produced the last Bessemer Steel made in Britain in 1974. It was brought to the Museum in 1978 as an example of the revolutionary steelmaking process which first took off in Sheffield. The Bessemer process - the conversion of iron into steel - was invented and patented by Henry Bessemer in 1856. The egg-shaped converter was tilted down to pour molten pig iron in through the top, then swung back to a vertical position and a blast of air was blown through the base of the converter in a dramatic fiery ‘blow'. Spectacular but dangerous flames and fountains shot out of the top of the converter. The converter was tilted again and the newly made steel was teemed or poured out. The first converters could make seven tonnes of steel in half an hour. In 1858 Henry Bessemer moved to Sheffield and licensed his method to two steelmakers, John Brown and George Cammell, who both began to produce Bessemer Steel on an unprecedented scale by 1860.

Others soon followed and within 20 years, Sheffield alone was producing 10,000 tons of Bessemer steel every week (this was almost a quarter of the country's total output). The invention marked the beginning of mass steel production, as huge amounts could be produced in a relatively short time compared to crucible steel production. The steel was most widely used for the railways that were stretching around the world. Plan Your Visit Henry Bessemer - The Steel Man Henry Bessemer - The Steel Man Henry Bessemer - The Steel Man Henry Bessemer and the Production of Steel By Mary Bellis Updated August 18, 2016. Sir Henry Bessemer, an Englishman, invented the first process for mass-producing steel inexpensively in the 19th century. It was an essential contribution to the development of modern day skyscrapers. The First System for Manufacturing Steel An American, William Kelly, initially 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. Air was blown through molten pig iron to oxidize and remove unwanted impurities. This was Bessemer’s starting point.

When Kelly went bankrupt, Bessemer – who had been working on a similar process for making steel – bought his patent. Bessemer patented "a decarbonization process utilizing a blast of air" in 1855. Modern Steel Modern steel is made using technology based on Bessemer's process. On the making of the first steel ingot, Bessemer said: "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, and 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 percent; 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 10 or 12 minutes, when the carbon contained in grey pig iron to the extent of about 3 percent 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 it 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 10 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." Bessemer was knighted in 1879 for his contributions to science. The "Bessemer Process" for mass-producing steel was named after him. Robert Mushet is credited with inventing tungsten steel in 1868, and Henry Brearly invented stainless steel in 1916. 1.2_invent.html INVENTING THE PROCESS An invention must be nursed as a mother nurses her baby, or it inevitably perishes. 10 From the start, the Bessemer process -- the most important technique for making steel in the nineteenth century -- was bound up with powerful institutions; in this respect, its transfer and development by American railroads continued a pattern set out by its English inventor. While at least five English or American inventors devised processes for making steel by blowing steam or air through molten iron, it was Henry Bessemer's process that became the most widely used. His technical ingenuity was only the start.

A close examination of Bessemer's inventive activities shows that his process was inspired by association with powerful institutions, especially the military, that his efforts to develop and commercialize his process rescued it from failure and obscurity, and that his considerable flair for publicity and patronage were as important to his overall success as his original technical conception. "The Messrs. Bessemer, the great steel makers, [have] long been known to keep their own leading article writer.... Mr. Bessemer's investing in what some might deem a luxury was a powerful natural step on his part," wrote the Engineer. "Few of the many investments Mr. Bessemer has made during his career have been more promising." "Bessemerizing" was understood by his peers as a social as well as technical achievement. 11 As a young man, Henry Bessemer proved himself adept at lining up prominent patrons behind his mechanical inventions. The son of a French emigre who had talked his way into the English Mint, then retired to the countryside, Bessemer came to London at age 17 and made a living by executing artistic castings, printing specialty items, and making metal dies.

By the time he was 23 his experiments in electrometallurgy had attracted the attention of Andrew Ure, the prominent philosopher of industrialism. Around the same time, Bessemer made his first notable invention, for the Inland Revenue Office. He devised a dated stamp that prevented the fraudulent reuse of revenue stamps on official documents. The invention reportedly brought the Treasury an additional £100,000 per year, and Bessemer a knighthood in 1879. 12 In the meantime Bessemer's inventive career flourished with his flair for high profile publicity. Windsor Castle tendered the first order for his novel machine-made embossed velvet, and the pioneering Coalbrookdale Iron Company tendered the first order for his machine-made bronze powder. In fact, a handsome income from manufacturing powdered bronze, which he conducted with great secrecy for some forty years, was the support for his inventive activities. At Baxter House, in the St. Pancras district of London, Bessemer set up an experimental factory and laboratory.

His work there, when added to his earlier efforts, netted Bessemer 34 patents on new methods for casting and setting type, for manufacturing paints, oils, varnishes, sugar, and plate glass, for constructing railway carriages, centrifugal pumps, and projectiles, and for ventilating coal mines. 13 While Bessemer had achieved modest success as a mechanical inventor, it was a military problem that led him to the manufacture of iron. "At the time when the Crimean War broke out," he wrote, "the attention of many persons was directed to the state of our armaments." Bessemer identified rifled ordnance as a key problem, and he devised a way of imparting spin to projectiles shot from a smooth-bore gun. When the British War Office rejected his idea Bessemer took it to France. In 1854, after demonstrating the revolving projectile at Vincennes, Bessemer heard from the officer in charge, Commander Claude Etienne Minié, the rifle inventor, that he mistrusted firing the heavy thirty-pound shot from the available twelve-pounder cast iron guns. Minié asked whether a new type of gun could be made to withstand such heavy projectiles.

This observation, by Bessemer's account, "instantly forced on my attention the real difficulty," i.e., withstanding the "heavy strains" caused by the projectiles, and he returned immediately to Baxter House determined "to study the whole question of metals suitable for the construction of guns." Within three weeks he filed the first in a famous series of patents on iron and steel. 14 Assisted at Baxter House by his brother-in-law, Bessemer began his gun-metal experiments by melting various mixtures of pig iron (the crude product of smelting iron ore), blister steel (a refined and expensive metal), and scrap in a standard iron-melting reverberatory furnace, producing enough metal to cast a model gun. 15 Then Bessemer's experiments took an unexpected twist: Some pieces of pig iron on one side of the bath attracted my attention by remaining unmelted in the great heat of the furnace, and I turned on a little more air through the fire-bridge with the intention of increasing the combustion. On again opening the furnace door, after an interval of half an hour, these two pieces of pig still remained unfused.

I then took an iron bar, with the intention of pushing them into the bath, when I discovered that they were merely thin shells of decarburised iron ... showing that atmospheric air alone was capable of wholly decarburising grey pig iron, and converting it into malleable iron without puddling or any other manipulation. Thus a new direction was given to my thoughts, and after due deliberation I became convinced that if air could be brought into contact with a sufficiently extensive surface of molten crude iron, it would rapidly convert it into malleable iron. 16 This anomaly, the shell of decarburized iron, led Bessemer to invent a process that reshaped the iron and steel industry. INSERT Figure I.1 Bessemer's Early Steel Making Experiments (1854-55) Now, hot on the trail, Bessemer built a crucible with a blow pipe extended into its center. Into the crucible he poured about 10 pounds of unrefined pig iron and then placed the apparatus into a hot furnace; after 30 minutes of blowing air into the metal, he found the crude iron had become malleable iron.

This experiment proved air could decarburize pig iron, turning it into a useful product, yet the furnace surrounding the crucible still consumed copious amounts of fuel. Bessemer's real insight was to get rid of the furnace entirely. For this he built a four-foot tall, open-mouthed cylinder with openings, or tuyères, to blow air into the metal from the bottom. As Bessemer related it, at first the blast bubbled quietly through the seven hundredweight of molten pig iron in the vessel, with the opening emitting some sparks and hot gases. Suddenly, after ten minutes, white flames shot forth. "Then followed a succession of mild explosions, throwing molten slags and splashes of metal high up into the air, the apparatus becoming a veritable volcano in a state of active eruption." Unable to approach the out-of-control converter, Bessemer and his assistants could only watch until the eruption quieted after ten minutes more. On tapping the converter and casting an ingot, Bessemer identified the metal as wholly decarburized malleable iron -- the product he desired. And except for melting the crude iron in the first place, no fuel was used.

17 INSERT Figure I.2 Bessemer's Optical Glass Furnace (c. 1850) In the following weeks Bessemer sought to tame the violent blow. To deflect the flame he placed a cast iron grate above the opening, but the white-hot blast melted it. He then tried lessening the blast by decreasing the number of tuyères, their diameter, or the pressure of the air. These changes indeed reduced the heat, in one case leaving an entire converter full of solid iron. Resigning himself to a violent blow, Bessemer sought to contain it in a converter featuring a cone-shaped upper chamber (which strikingly resembles an earlier furnace he devised to melt optical glass; see Figure I.2). This familiar arrangement harmlessly vented the hot gases. With this vertical, fixed, two-chamber converter, Bessemer achieved the successful conversion of crude iron to steel. 18 INSERT Figure I.3 Publicity for Bessemer's First Converter (1856) Bessemer quickly swung his publicity machine into action.

He showed his converter to George Rennie, president of the mechanical sciences section of the British Association for the Advancement of Science (BAAS), where a decade earlier James Neilson had showcased his hot blast furnace, the invention that gave iron smelting its characteristic form and name. Rennie was duly impressed and invited Bessemer to give a talk at the upcoming BAAS meeting in Cheltenham. There, on 13 August 1856, Bessemer presented "The Manufacture of Malleable Iron and Steel without Fuel." If this seemingly absurd concept produced snickers before the talk, few remained afterward. It was "a true British nugget," stated the engineer James Nasmyth. The next day's report in The Times reproducing Bessemer's 2,000 word essay attracted the attention of Edward Riley, chemist of the Dowlais Iron Company, the leading Wales firm. Two weeks after the BAAS talk Dowlais purchased the first license for £10,000, just as the Illustrated London News featured Bessemer's converter in action (see Figure I.3).

Early in September Bessemer staged an exhibition at Baxter House for "some seventy or eighty of the most eminent persons connected with the manufacture of iron." 19 Trial converters were erected in the following months by Dowlais Iron (Wales), Messrs. Galloway. (Manchester), Govan Ironworks (Glasgow), and Butterley Iron (Derbyshire), but their trials were disastrous. Many found the new metal was too brittle to roll or forge into useful shapes; at the rolling mill at Dowlais Iron, for instance, "the ingots ... were crushed into rough gravel like powder, showing a total want of malleability." 20 To diagnose the problem, Bessemer consulted with the prominent metallurgists T. H. Henry.H.; and John Percy, while the Dowlais chemist continued his investigations. Bessemer had by happenstance used a grey Blaenavon pig iron that was exceedingly low in phosphorus content. Nearly all other pig irons available in Britain contained significant amounts of this element, and they yielded an obviously inferior product. Bessemer first tried to improve common grades of British pig iron by using different fluxes and by passing various gases through the liquid metal.

When this line of experiments failed Bessemer decided to switch to Swedish pig iron, a premium grade often used in making Sheffield's fiendishly expensive crucible steel. Finding and matching suitable pig irons was a hit or miss proposition for several years, until the key role of phosphorus -- and especially its relation to brittleness in steel -- was recognized in the early 1860s. It was from bitter experience that Bessemer later remarked, "An invention must be nursed as a mother nurses her baby, or it inevitably perishes." 21 INSERT Figure I.4 Plan of Bessemer Plant at Sheffield (1858) Another problem was that Bessemer had announced his process as if it were trouble-free when it manifestly was not. Backers of the several commercial ventures were especially annoyed that their substantial license payments had not brought them a workable process. Their persistent difficulties eventually forced Bessemer to refund some £32,500 in licensing fees. A complete commercial failure was at hand. What saved Bessemer was his prior experience in developing and commercializing the manufacturing ventures in embossed velvet and bronze powder, and the money he had realized from them.

Bessemer had furthermore retained full rights to his patent. These resources together gave Bessemer the insight and means to build a steel works of his own in Sheffield (see Figure I.4). In 1858 Bessemer formed a partnership with his brothers-in-law Robert Longsdon and William Allen, as well as with his machinery suppliers William and John Galloway of Manchester. For its first year the steel works produced an odd product. A stream of the molten steel was run into a vat of water and solidified as pellets; then a mixture of these pellets from several batches was remelted in one of Sheffield's famous clay crucibles. Only after a visit in 1859 from the Swede Göran Göransson, the first licensee to make commercial quantities of the new steel, did Bessemer begin producing steel directly from the converter without the crucible remelting. While the details of his contribution remain unclear to this date, Göransson may have turned the corner. The Sheffield works lost £1,800 in its first two years of operation (1858-59) then made increasingly handsome profits thereafter.

22 INSERT Figure I.5 Bessemer's Tilting Converters (1858) Yet there is no gainsaying Bessemer's own substantial efforts. He helped commercialize in Cumberland and Lancashire newly discovered beds of non-phosphorus hematite iron ore, which could easily and economically be smelted and converted into a malleable steel that was easily rolled or forged. He also worked to devise a fire brick lining to contain the white-hot metal in the converting vessel. For the Sheffield works in 1858 Bessemer adopted a tiltable converter, a major innovation again prefigured in the optical glass furnace. The physical arrangement of the stationary vertical converter had required that the air blast begin before the crude iron entered the converting vessel and last until the converted steel left; otherwise the metal would simply run out the bottom. The problem was that any delay in casting the converted steel into ingots could result in the air blast cooling the metal, and there was always the spectre of the cold converter filled with solid metal. The solution Bessemer devised was to tilt the converter so that the air blast was needed only for the duration of the converting blow (see Figure I.5).

With this arrangement, minor delays no longer could ruin the batch of steel. With new sources of low-phosphorus pig iron, a more durable vessel lining, and the tilting converter, Bessemer had achieved technical if not yet commercial success. 23 Bessemer's commercial success was a product of his ability to arrange financing, retain patent control, and fend off rivals. Again the publicity machine was fired up. Bessemer's exhibit at the London International Exhibition in 1862 attracted the attention of John Platt -- an engineer and industrialist -- and M.P. from Oldham. Impressed by the process (and by the profits finally coming to the Sheffield works) Platt quickly assembled an investment syndicate that offered to purchase a one-fourth share of the patent. Wary of losing control, Bessemer pressed for a more advantageous deal. The two parties soon came to agreement that the syndicate would make an investment equivalent to a one-fourth share for £50,000 but that Bessemer and Longsdon would retain complete control of the patents, thus retaining the right to grant licenses and to raise or lower royalties.

Three weeks after the Exhibition's opening, the deal was concluded after dinner at the Queen's Hotel in Manchester, when each of the ten investors personally handed £5,000 to Bessemer and Longsdon. This timely infusion of capital added momentum to commercializing the new process. Bessemer's original five partners in the Sheffield works racked up profits over 14 years totalling 8,100 percent, the members of the Platt syndicate, a still-handsome 520 percent. 24 While Bessemer was of course not the only person to experiment with blowing air or steam through molten metal, his ability to coopt potential rivals was unmatched. Following the BAAS paper Bessemer had declined a buy-out offer from the Ebbw Vale Ironworks, another prominent Wales concern. Instead, Ebbw Vale purchased a vaguely similar and therefore rival patent of Joseph G. Martien, and subsequently the firm's own furnace master gained several patents for blowing air into and over various mixtures of scrap iron. Around 1864 Ebbw Vale decided to exploit these patents by forming a new joint stock company with a very large capitalization.

When Bessemer heard of these plans he threatened not only filing a lawsuit but also setting his publicity machine to work covering London's financial district with posters, placards, and handbills to prevent the stock subscription from going forth. In the event a compromise was arranged between Bessemer and the principals of Ebbw Vale, Abraham Darby and Joseph Robinson. It turned out that Ebbw Vale did not actually own the furnace master's patents, which Bessemer purchased for £5,000; the new firm took out a regular license and paid standard royalties, except that Bessemer deducted £25,000 from their first royalties in exchange for the Martien patents. Bessemer now possessed his principal rival's patents, he had another licensee, and, despite the stiff price, he netted some £50,000 or £60,000 from the deal. Thus, as Bessemer put it, "happily was removed the last barrier to the quiet commercial progress of my invention throughout Europe and America." 25 10 . Henry Bessemer, An Autobiography (London: Offices of Engineering, 1905), 121.

11 . See "'Bessemerizing' and the Nitrate Steel Process," Engineer 25 (7 Feb. 1868): 100. 12 . Dictionary of National Biography, s.v., "Sir Henry Bessemer," XXII: 186; Geoffrey Tweedale, s.v. "Sir Henry Bessemer," Dictionary of Business Biography (London: Butterworths, 1984), I: 309-12. 13 . In the near absence of reliable documents, apart from the Dowlais Iron papers, historians must interpret Bessemer's always-boastful and sometimes-unreliable Autobiography. Bessemer's personal papers were apparently destroyed; see Alan Birch, The Economic History of the British Iron and Steel Industry, 1784-1879 (New York: Kelley, 1968), 320 n 19; Jeanne McHugh, Alexander Holley and the Makers of Steel (Baltimore: Johns Hopkins University Press, 1980), 76 n 1.

Notable for comparing Bessemer's account with primary documents is Alan Birch, "Henry Bessemer and the Steel Revolution," Nachrichten aus der Eisen-Bibliothek (Schaffhausen) 28 (1963): 129-36; 30 (1964): 153-59; and Edgar Jones, "The Transition from Wrought Iron to Steel Technology at the Dowlais Iron Company, 1850-1890," in Jonathan Liebenau, ed., The Challenge of New Technology: Innovation in British Business Since 1850 (Gower: Aldershot, 1988), 43-57. On Bessemer as a mechanical inventor see Bessemer, Autobiography, 4-137, 329-32; Ernst F. Lange, "Bessemer, Göransson and Mushet: A Contribution to Technical History," Memoirs Manchester Lit & Phil Society 57 no. 17 (1913): 2-5, 33-8. Bessemer gained a total of 117 patents. 14 .

Bessemer, Autobiography, 134-42, quotes 130, 136-37; Lange, "Bessemer," 4-5. 15 . Blister steel resulted from baking bars of iron that contained essentially no carbon in furnaces filled with charcoal; the process, known as cementation, required as long as a week before the desired amount of carbon in the charcoal diffused into the iron bars, producing blisters on their surface; blister steel melted in clay crucibles became the "crucible steel" that made Sheffield famous. See Geoffrey Tweedale, Sheffield Steel and America: A Century of Commercial and Technological Interdependence, 1830-1930 (Cambridge: Cambridge University Press, 1987), chap. 2. 16 . Bessemer, Autobiography, 142; and Tweedale, "Bessemer," 310. 17 . Bessemer, Autobiography, 142-4, quote 144; Bessemer, "The Origin of the Bessemer Process," Iron Age 58 (3 Dec.

1896): 1065-71; Lange, "Bessemer," 4-5. In modern terms, the oxygen in the air and the silicon and carbon in the metal combined in a violent combustion; such a chemical understanding was yet to emerge. 18 . Bessemer, Autobiography, 144-54; and Henry Bessemer, "On the Manufacture of Cast Steel, Its Progress, and Employment as a Substitute for Wrought Iron," Engineer (London) 20 (15 Sept. 1865): 173-4. 19 . W. T. Jeans, The Creators of the Age of Steel (New York: C. Scribner's Sons; London: Chapman & Hall, 1884), quote 44; Bessemer, Autobiography, 154-68, Nasmyth letter reproduced in figure 93. For the first licenses, see H. Bessemer and R. Longsdon agreement with Dowlais Iron Co. 27 Aug. 1856; Bessemer and Longsdon to G.T. Clark 28 Aug.

1856, 5 Dec. 1856; Bessemer and Longsdon to Dowlais Iron Co. 3 Sept. 1856, D/DG Section C Box 2, DI; Madeleine Elsas, ed., Iron in the Making: Dowlais Iron Company Letters, 1782-1860 (Cardiff: Glamorgan County Council and Guest Keen Iron and Steel, 1960), 193-4, 205-6; Edgar Jones, "Wrought Iron to Steel at Dowlais Iron," 51, gives the Dowlais license at £20,000. 20 . Lowthian Bell, "Invention of the Bessemer Process" MS. 26 Aug. 1903; and Bell to H. M. Howe, 23 Mar. 1899, 3: Patent Applications of Robert Hadfield for the Manufacture of Manganese Steels 1896, HMH. 21 .

Bessemer, Autobiography, quote 121, 170-4, 182-4; Lange, "Bessemer," 7-12. The precise role of Henry and Percy remains unclear. Lowthian Bell doubted that even Blaenavon pig iron could be made into Bessemer steel; Bell "Invention." 22 . W. M. Lord, "The Development of the Bessemer Process in Lancashire, 1856-1900," Newcomen Society Trans. 25 (1945-47): 165-7; W. H. Chaloner, "John Galloway (1804-1894), Engineer of Manchester, and his 'Reminiscences'," in D. A. Farnie and W. O.

Henderson, eds., Industry and Innovation (London: Cass, 1990), 99-121, on 116-17; Bessemer, Autobiography, 171-77, 213-15, 334; Lange, "Bessemer," 13-7; Bessemer, "On the Manufacture of Cast Steel," 173. Total capital for the Sheffield works was £12,000: Bessemer and Longsdon subscribed about £6,000; W. & J. Galloway, £5,000; William D. Allen, £500; Tweedale, "Bessemer," 310-11.

Profit or (loss) for the Sheffield works Bessemer, Autobiography, 334 1858 (£729) 1863 £10,968 1859 (£1093) 1864 £11,827 1860 £923 1865 £3,949 1861 £1,475 1866 £18,076 1862 £3,685 1867 £28,622 23 . Lord, "Development," 169-74; Bessemer, Autobiography, 148-51, 178-81, 256-90; Lange, "Bessemer," 18-20. 24 . According to the Queen's Hotel anecdote, Bessemer's share of the partnership was 80 percent, Longsdon's, 20 percent.

Bessemer, Autobiography, 177, 234-37, 334; Lange, "Bessemer," 28-30. Ironically, Bessemer tried without success to interest the War Department and the Admiralty in his process; Bessemer, Autobiography, 184-255. 25 . For others' experiments treating molten iron with blasts of air or steam similar to Bessemer's see Theodore A. Wertime, The Coming of the Age of Steel (Leiden: E. J. Brill, 1961), 284-87; J. A. Cantrell, James Nasmyth and the Bridgewater Foundry: A Study of Entrepreneurship in the Early Engineering Industry (Manchester: Manchester University Press, 1984), 123-26. Bessemer, Autobiography, 168-70, 291-303, quote 303; Lange, "Bessemer," 21-4. The views and opinions expressed in this page are strictly those of the page author.

The contents of this page have not been reviewed or approved by the University of Minnesota. Workington Iron and Steel The Acid Bessemer process was invented in 1856 and has been in use at Workington since 1872 Workington Iron and Steel. Workington is situated in West Cumbria (formerly West Cumberland) on the fringes of the Lake District in the North West of England. On 6 November 1856 the Workington Haematite Iron Company Ltd. was established to manufacture pig iron from locally mined heamatite ore.Two blast furnaces were erected at Oldside, just north of the town. Bessemer steelmaking commenced in June 1877. In 2005, CorusRail continue to roll rails from reheated steel blooms, but the mill will close down in 2006. When I was a small boy, my dad, who was a shift production manager in the Bessemer department would occasionally take my brother and I there to visit. The highlight was when we got the chance to control one of the two Bessemer converters under the watchful gaze of the blower and his team in the blower's box.

The blower would keep his foot pressed on the dead man's pedal and we'd gaze in wonderment through the window as a vessel with 25 tons of molten metal would respond to our hand movements on the control column. The bessemer converter was charged with molten iron in the horizontal position, the air blast was turned on, and then the vessel rotated to the vertical position (shown) while the bessemer shop was showered by an inferno of sparkling metal particles like the most fantastic fireworks display ever seen. Looking back, it is easy to understand what a deep impression that left on me. I consider myself privileged to have experienced the spectacle of steel making by the bessemer process. I am doubly fortunate to be amongst those who witnessed the final heat in July 1974. This is my small tribute to those West Cumbrian men and women who have iron and steel in their blood and to the generations who made Workington rails a familiar sight around the world. Visit the railway wherever you are, and there is a good chance you'll see Workington proudly rolled into the web of the rail. Phil Baggley.

Question: The Bessemer process was invented in 1856 for the production of what material?
Answer: Steel