The principles of an optimal process of carbonization have been defined in order to produce tube steel grades from semi-product, melted in a state-of-the-art high power electric arc furnace. According to the results of laboratory and production researches, the significance of deoxidation and carbonization, quality of carbonization material used, carbon content correction time, has been proved. The effectiveness of silicon carbide use has been described, as an option of the complex solution of carbonization and deoxidation of the semi-product.