National Research Technological University “Moscow Institute of Steel and Alloys” — NITU MISiS, Moscow, Russia:

Kurnosov V. V., Cand. Phys. & Math., Head of the Chair of Thermal Physics and Ecology of Metallurgical Production 

Levitsky I. A., Cand. Eng., Assist. Prof. of the Chair of Thermal Physics and Ecology of Metallurgical Production, lewwwis@mail.ru

Pribytkov I. A., Cand. Eng., Deputy Head of the Chair of Thermal Physics and Ecology of Metallurgical Production

Relationship between required heat input, temperature gradient along cross section of a cylindric billet and thickness of scale formed on this billet (from one side) and its heating time from 600 to 1200 ^оC according to the different technological conditions (from other side) has been examined via the method of mathematical simulation. The billet of steel 20 with three different diameters has been investigated in the conditions of heating with permanent rate as well as heating with one or two holding periods with different heating rates. It was shown that top values of consumed power and its distribution as well as local temperature gradient across billet section depend essentially on its size and heating rate. It was established that usage of dual-stage heating allows to decrease maximal value of thermal power consumption, to decrease temperature gradient along the billet cross section, to lower scale forming. It is possible to choose such dualstage heating conditions that its duration will correspond practically with duration of the single-stage heating procedure. Additionally, it is shown that temperature relationships of thermal-physical parameters of heating metal have substantial influence on features of variation of consumed power and temperature gradient along the billet cross section. The developed technique and basic results can be applied for heating and thermal furnaces in machine-building and metallurgy, as on designing stage, as well in development of technological procedures for rolling and heat treatment.

1. Arutyunov V. A., Levitskii I. A., Ibadullaev T. B.  Developmment of methods for mathematical modeling of thermophysical processes in industrial fuel furnaces. Metallurgist. May, 2011. Vol. 55, No. 1–2. pp. 3–9.

2. Arutyunov V. A., Bukhmirov V. V., Krupennikov S. A. Matematicheskoe modelirovanie teplovoy raboty promyshlennykh pechey (Mathematical modeling of the thermal performance of industrial furnaces). Moscow : Metallurgiya, 1990. 240 p.

3. Zaludova M., Smetana B., Zla S., Dubrovska J., Matejka V. Latent heats of phase transformations of steel in the low temperature region. 20-th International Metallurgical and Materials Conference “Metal-2011”. Brno, Czech Republic, EU, May 18–20, 2011.

4. Kazantsev E. I. Promyshlennye pechi. Spravochnoe rukovodstvo dlya raschetov i proektirovaniya. Vtoroe izdanie, dopolnennoe i pererabotannoe (Industrial furnaces. Reference guide for calculating and projecting. Second edition, revised and enlarged). Moscow : Metallurgiya, 1975. 368 p.

5. Lykov A. V. Teoriya teploprovodnosti. Uchebnoe posobie (Theory of thermal conductivity. Tutorial). Moscow : Vysshaya shkola, 1967. 600 p.

6. A Heat Transfer Textbook. John H. Lienhard IV and John H. Lienhard V. 3rd edition. Cambridge, MA : Phlogiston Press, 2008. 762 p.

7. Carl L. Yaws. Handbook of Thermal Conductivity. Gardners Books, 1995. 356 p.

8. George E. Totten. Steel Heat Treatment. Taylor&Francis, 2006. 848 p.

9. Mäki A. M., Österman P. J., Luomala M. J. Numerical study of the pusher-type slab reheating furnace. Scandinavian Journal of Metallurgy. 2002. No. 31. pp. 81–87.

10. Peretyatko V. N., Temlyantsev N. V., Temlyantsev M. V., Mikhaylenko Yu. E. Nagrev stalnykh slyabov (Steel slabs heating). Moscow : Teplotekhnik, 2008. 192 p.

11. Temlyantsev M. V., Mikhaylenko Yu. E. Okislenie i obezuglerozhivanie stali v protsesse nagreva pod obrabotku davleniem (Oxidation and decarburization of steel during the heating under the plastic working). Moscow : Teplotekhnik, 2006. 200 p.