NLMK Dansteel A/S (Frederikswerk, Denmark):

E. A. Goli-Oglu, Cand. Eng., Process Developer, e-mail: Egoli-Oglu@yandex.ru

Growing interest in the production of heavy plates in thickness range 60-100 mm and steel grades S420M / S420ML in compliance with EN 10025-4:2019 is noted. The first part of publication provides an overview of present-day requirements to the chemical composition and mechanical properties of S420M and S420ML heavy plates. Authors describes the specifics of designing the chemical composition and selecting the technological parameters for the thermomechanical processing with accelerated cooling (TMCP+ACC) of heavy plates in high thickness groups. Publication provides description of the main equipment of NLMK DanSteel Mill Quarto 4200 that is used for production of heavy plates from low-carbon structural steels by using TMCP+ACC process. The second part of publication provides Brief description of the specific temperature and cooling parameters of rolling and cooling stages during production of 60-100 mm heavy plates in TMCP+ACC is given, and the effect of these parameters on the formation of the final microstructural condition and mechanical properties in different thickness layers of heavy plates is investigated.

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