Steelmaking practices

Steelmaking Process and Piping Specs. ANSI B31.3 specifically limits steelmaking processes to electric furnace, open hearth or deoxidized Acid Bessemer steel. On the other hand, both API 5L and ASTM A53 permit undeoxidized Bessemer steel. In using these specifications, it is necessary to clearly state any limitations of steelmaking practice that may be considered desirable to ensure adequate quality. 

Before the invention of the Bessemer process for steelmaking in 1856, only the cementation and cmcible processes were of any industrial importance. Although both of the latter processes had been known in the ancient world, thek practice seems to have been abandoned in Europe before the Middle Ages. The cementation process was revived in Belgium around 1600, whereas the cmcible process was rediscovered in the British Isles in 1740. 

Electric-Arc Furnace. The electric-arc furnace is by far the most popular electric steelmaking furnace. The carbon arc was discovered by Sir Humphry Davy in 1800, but it had no practical appHcation in steelmaking until Sir William Siemens of open-hearth fame constmcted, operated, and patented furnaces operating on both direct- and indirect-arc principles in 1878. At that early date, the avadabiHty of electric power was limited and very expensive. Furthermore, carbon electrodes of the quaHty to carry sufficient current for steel melting had not been developed (see Furnaces, electric). 

Describe typical sources and types of air emissions resulting from steelmaking. What are some pollution prevention practices used in this industry What are some of the emission control devices used and for what purposes ... 

Flux, J. H. Containment of Melting Shop Roof Emissions in Electric-Arc Furnace Practice. Ironmaking Steelmaking 1 (1974) no. 3, pp. 121-136. 

All rare earth metals can be characterised as being electropositive with respect to most other metals this fact, coupled with their large atomic radius and high reactivity towards non-metals, points the way to their widespread use as alloying constituents. However, in the manufacture of ductile iron and in steelmaking it is practice to use mischmetal or mixed rare earth silicides as the rare earth additive and from purely cost considerations this situation is unlikely to change significantly. 

Some 3,000,000 metric tons of O2 are used annually for steelmaking in the United States alone. This practice has the following advantages which more than compensate for the extra cost ... 

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