Sunday, October 12, 2008

Learning from the past (1)

Hi All,

That process innovation, finding new technology breaktrhoughs, was the direction to increase productivity drastically is easily shown from several examples from the past. I'm going to do a series of these in the following boggs.
In England the production of steel and iron was improved in the late eighteenth century resulting in a large mechanization of the production systems. The effect was that where most production was done at low scale, a large scale mass production came about.
The avalability of iron and steel made it possible to produce trains, bridges, railway stations, etc.

Inventing better methods to manufacture steel resulted in greater quantity and quality.Notice in the following story the different technological inventions that made it possible to come to a uniform way of producing. (the following text was adapted from http://science.jrank.org/)


Because the focus of improving steel must have been the talk of that century it is not surprizing that William Kelly of the United States, and Henry Bessemer of England, both working independently, discovered the same method for converting iron into steel. Kelly built his first converter in 1851 and received an American patent in 1857. In 1856 Bessemer completed his vertical converter, and in 1860 he patented a tilting converter which could be tilted to receive molten iron from the furnace and also to pour out its load of liquid steel. The Bessemer converter made possible the high tonnage production of steel for ships, railroads,bridges and large buildings in the mid-nineteenth century.
However, the steel was brittle from the many impurities. An English metallurgist, Robert F. Mushet, discovered in 1856 that adding an iron alloy (spiegeleisen) containing manganese would remove the oxygen. Around 1875, Sidney G. Thomas and Percy Gilchrist, two English chemists, discovered that by adding limestone to the converter they could remove the phosphorus and most of the sulfur.In England, another new furnace was introduced in 1861 by two brothers, William and Frederick Siemans. This was the open-hearth furnace, also known as the regenerative open-hearth because the outgoing hot gases were used to preheat the incoming air. Pierre Émile Martin of France improved the process in 1864 by adding scrap steel to the molten iron to speed purification. During this period hardened alloy steels came into commercial use; Mushet made a high carbon steel in 1868 which gave tools longer life in France, a chromium steel alloy was produced in 1877 and a nickel steel alloy in 1888. An Englishman, Sir Robert Hadfield, discovered in 1882 how to harden manganese tool steel by heating it to a high temperature and then quenching it in water.Around 1879, the electric furnace was developed by William Siemans. This furnace was used very little prior to 1910 because of the high electrical costs and the poor quality of electrodes used to produce the arc for melting.

The open-hearth furnace was the most popular method of steel production until the early 1950s.
Isn't this remarkable? The basic technoloy stayed the same during almost 90 years! Clearly no major improvements have been found.
Pure oxygen became more economical to produce in large quantities and in 1954 the first basic oxygen process facility opened for production in the United States. Today, most of the world's steel is made by either a basic oxygen furnace or an electric furnace. Strange that we are still working with technology developped in the 18the century. (adapted from here)
Have a great day,
Ives

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