Bedson, George

SUBJECT AREA: Metallurgy

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b. 3 November 1820 Sutton Coldfield, Warwickshire, England

d. 12 December 1884 Manchester (?), England

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English metallurgist, inventor of the continuous rolling mill.

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He acquired a considerable knowledge of wire-making in his father's works before he took a position in 1839 at the works of James Edleston at Warrington. From there, in 1851, he went to Manchester as Manager of Richard Johnson \& Sons' wire mill, where he remained for the rest of his life. It was there that he initiated several important improvements in the manufacture of wire. These included a system of circulating puddling furnace water bottoms and sides, and a galvanizing process. His most important innovation, however, was the continuous mill for producing iron rod for wiredrawing. Previously the red-hot iron billets had to be handled repeatedly through a stand or set of rolls to reduce the billet to the required shape, with time and heat being lost at each handling. In Bedson's continuous mill, the billet entered the first of a succession of stands placed as closely to each other as possible and emerged from the final one as rod suitable for wiredrawing, without any intermediate handling. A second novel feature was that alternate rolls were arranged vertically to save turning the piece manually through a right angle. That improved the quality as well as the speed of production. Bedson's first continuous mill was erected in Manchester in 1862 and had sixteen stands in tandem. A mill on this principle had been patented the previous year by Charles While of Pontypridd, South Wales, but it was Bedson who made it work and brought it into use commercially. A difficult problem to overcome was that as the piece being rolled lengthened, its speed increased, so that each pair of rolls had to increase correspondingly. The only source of power was a steam engine working a single drive shaft, but Bedson achieved the greater speeds by using successively larger gear-wheels at each stand.

Bedson's first mill was highly successful, and a second one was erected at the Manchester works; however, its application was limited to the production of small bars, rods and sections. Nevertheless, Bedson's mill established an important principle of rolling-mill design that was to have wider applications in later years.

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Further Reading

Obituary, 1884, Journal of the Iron and Steel Institute 27:539–40. W.K.V.Gale, 1969, Iron and Steel, London: Longmans, pp. 81–2.

LRD