Bessemer Process
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.
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 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.