Saint Petersburg Electrotechnical University “LETI”, Saint Petersburg, Russia:

V. B. Demidovich, Professor, Chief Researcher (Inter-Branch Laboratory “Modern Electrotechnologies”), e-mail: vbdemidovich@mail.ru

National Mineral Resources University, Saint Petersburg, Russia:
I. I. Rastvorova, Assistant Professor of a Chair of Electronic Systems

Problems of precision induction heating of the blanks of non-ferrous metals alloys such as titanium, zirconium, niobium, tantalum and some others are discussed. Induction heating of non-ferrous metals has some features that should be taken into account on developing the proper equipment. Because of low thermal conductivity and high thermal losses from the surface, the maximum temperature inside the blank is achieved and can’t be measured with a pyrometer. Absolutely uniform heating in inductors is unavailable even theoretically. At the same time, precision heating with high homogeneity extent of the temperature field provides high quality of nonmagnetic metals blanks plastic deformation. Determination of the minimum accessible temperature field unevenness on the blank being heating by induction method, plays an essential role in the heating technology development and induction plant designing. There is examined a complex of the factors affecting quality of the cylindrical non-magnetic blanks heating in inductors. To achieve minimum temperature gradient through the diameter and the length of the blank when heated, different construction and heating mode optimization channels are used. These include the frequency, required power and heating time selection, active and passive means of the heat sources distribution spatial adjustment. Procedure of the induction heater mode and construction is automatic optimization is elaborated. Computational modelling is an integral part of equipment designing and induction heating technology development. There is presented an example of electromagnetic and temperature field calculation under the zirconium blank optimum heating in the induction periodical heater.

1. Demidovich V. B., Chmilenko F. V. Kompyuternoe modelirovanie ustroystv induktsionnogo nagreva (Computer modelling of induction heating equipment). Saint Petersburg : Publishing House of Saint Petersburg Electrotechnical University “LETI”, 2013. 160 p.
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5. Rapoport E. Ya., Pleshivtseva Yu. E. Optimalnoe upravlenie temperaturnymi rezhimami induktsionnogo nagreva (Optimal control of temperature modes of induction heating). Moscow : Nauka, 2012. 309 p.
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9. Demidovich V. Computer simulation and optimal designing of energy-saving technologies of the induction heating of metals. Thermal Engineering. 2012. Vol. 59, No. 14. pp. 1023–1034.
10. Tavakoli M. H., Karbaschi H., Samavat F. Influence of workpiece height on the induction heating process. Mathematical and Computer Modelling. 2011. Vol. 54, No. 1/2. pp. 50–58.
11. Peysakhovich V. A. Sintez chislennykh i analiticheskikh metodov pri raschete induktorov dlya nagreva tsilindricheskikh tel (Synthesis of numerical and analytical methods during the calculation of inductors for the heating of cylindric bodies). Induktsionnyy nagrev = Induction Heating. 2013. No. 2 (24). pp. 4–14.
12. Demidovich V. B., Rastvorova I. I. Induction Heating in the Processing of Ti&Zr. Journal of Electromagnetic Analysis and Applications. 2014. No. 6. pp. 404–411.