Відпрацювання оптимальних режимів електромагнітного перемішувача в кристалізаторі при безперервному розливанні квадратних заготовок в промислових умовах

• Date: 2023
• Main Author: Верзілов, О. П.
• Format: Article
• Language: Ukrainian
• Published: National Academy of Sciences of Ukraine, Physical-Technological Institute of Metals and Alloys of NAS of Ukraine 2023
• Subjects: металургійний мікро-завод; електромагнітний перемішувач; кристалізатор; безперервне розливання; сортова заготовка
• Online Access: https://plit-periodical.org.ua/index.php/plit/article/view/development-optimal-modes-electromagnetic-mixing-mold-during-con
• Journal Title: Casting Processes

Physico-Techological institure of Metals and Alloys of NAS of Ukraine (Kyiv, Ukraine) УДК 621.746.27:537.812 Electromagnetic mixing in the mold is one of the most effective methods of physical impact on liquid metal in order to form a high-quality surface and internal structure of a continuously cast ingot. This is due to the fact that the primary crust of the solidifying billets has a small thickness and its thermal resistance to heat transfer to the Crystallizer wall is minimal. Testing of optimal modes of electromagnetic mixing (EM) in the mold during continuous casting was performed for square billets of 120, 150, 180 mm in terms of improving their macrostructure. The principle of operation of EM is based on the principle of operation of an asynchronous three-phase motor, that is, the traveling magnetic field of EM interacts with eddy currents induced in a liquid metal and sets the latter in motion in the direction of movement of the magnetic field. The Danieli Rotelec mixer is mounted on a support that is part of a swing table independent of the Crystallizer. EM is located around themold body in the upper or lower positions. The EM is powered by a low-frequency power source to increase the depth of penetration of the magnetic field into the liquid phase of the mold ingot. The use of an electromagnetic mixing system of steel in a mold with the following parameters: current strength 280-380 a, current frequency 6 Hz, to improve the surface quality and internal structure of billets was tested. A series of swimming trunks was also poured with a 1-2-time change in the position of the tundish with submerged entry nozzle during the series (due to periodic lowering by 30 mm) along the height of the contact zone with the slag Belt and the EM operation zone to ensure the stability of submerged entry nozzle and the serial casting of 4-6 swimming trunks. In the process of mining, casting of 28 steel grades was mastered, a total of 84625.0 tons of long billet were cast, including 26462.09 tons (31.27 %) of vacuumed steel grades 25G2, 35G2F, 36G2S, 37G2S, 5lX42. the yield of suitable metal averaged 96.86 %.   References 1. Liao Y., Yao Y. (2013). Applications Analysis of the Technology of Mold Electromagnetic Stirring in a Steel Mill / Advanced Materials Research. V. 721. Р. 471–474.2. Efimov V. A. (1991). Metallurgical aspects of mixing alloys in a ladle and a solidifying ingot/ Processes of casting and crystallization of steel. Kyiv: IPL of the Academy of Sciences of the Ukrainian SSR. P. 3–12. [in Russian].3. Efimov V. A., Eldarkhanov A. S. (1995). Physical methods of influence on the processes of hardening of alloys. M.: Metallurgy. 272 P. [in Russian].4. Choudhary S. K. (2011). Influence of Modified Casting Practice on Steel Cleanliness. ISIJ International. V. 51. № 4. Р. 557–565.5. Sahoo P. P., Kumar A., Halder J., Raj M. (2009). Optimisation of Electromagnetic Stirring in Steel Billet Caster by Using Image Processing Technique for Improvement in Billet Quality / ISIJ International. V. 49. № 4. Р. 521–528.6. Lehman A., Sioden O., Kuchaev A. (2004). Application of electromagnetic mixing in steel production. Metallurgical and mining industry. No. 8, pp. 79–82. [in Russian].