NLMK Dansteel A/S (Fredriksvaerk, Denmark):

Goli-Oglu E. A., Cand. Eng., Process Developer, e-mail: ego@nlmk.com
Greisen Z., Cand. Eng., Chief Metallurgist
Bokachev Yu. A., Managing Director

The analysis of metallurgical quality of rolled sheet with thickness 80–150 mm from C–Mn–Si–Mo steel (16Mo3 according to EN10028-2 Euronorm), used for manufacture of shells of steam turbines is conducted based on the results of final and researching testings. These sheets have been manufactured on 4200 plate mill at NLMK Dansteel via hot rolling technology with consequent normalization. The paper presents data about variation of grain size and microstructure homogeneity depending on increase of final thickness of rolled sheet. Mechanical properties were examined in the temperature interval from +20 to +450 °С, and the temperature range for passing of dynamic deformation ageing as well as variation of features of deformation resistance with temperature rise are determined. Impact work was investigated in the temperature interval from +20 to -50 °С. The results of investigation were used during certification for production of steel sheets with width up to 150 mm from steel 16Mo3, used for manufacture of vessels operating under pressure at high temperatures, in accordance with the special directives TUV PED 2014/68/ EU and TUV AD2000.

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