Effect of additions on the production cost of steel and the cost-effectiveness of converter steelmaking

This article examines the effect of additional blowing on performance indices and production costs for the production of steel in the converter shop at the Chelyabinsk Metallurgical Combine. It is shown that deviations from prescribed steelmaking practices in the shop, the use of pig iron with an unstable chemical composition and temperature, the lack of information on the pig iron for use by the shop supervisor before the beginning of heats, the cold-charging of scrap with a low bulk density, the use of poor-quality lime, and other problems make it impossible to conduct the blow with the optimum blowing, temperature, and slag regimes. This makes it necessary to take corrective actions: heats are subjected to additional blowings to attain the required temperature and necessary contents of C, S, and P. More than 90% of the heats at the combine require additional blowing “for temperature” and as much as 18% need additional blowing “for phosphorus and sulfur.” It was established that the unit consumption of metallic charge materials and steel production costs are respectively 19.60 kg/ton and 249.39 rubles/ton higher for heats which receive additional blowing.