The electrosmelting shop at OAO UralStal is based on a system consisting of an arc furnace, a ladle-furnace unit, and a curvilinear continuous slab-casting machine supplied by SMS Demag. A considerable proportion of the shop's output consists of crack-sensitive tube steel and steel for thick-sheet production, including 10-15XCHД steel. Slab billet is cast from metal that has been produced from metal scrap (mainly scrap that has been purchased from elsewhere). A considerable proportion of the slabs are sent to the rolling shop without inspection or surface finishing. In producing steel sheet, certain problems arise: surface cracks of thick sheet, especially for 10-15XCHД steel; defects visible in ultrasound monitoring of thick sheet; stratification in the axial region of the sheet in impact-flexure tests; surface cracks on slabs of peritec-tic steel (13Г1С-У, 10ГФБЮ, etc.); macrostructural defects such as socket-like cracks, axial pores, axial chemical heterogeneity, and axial and liquational cracks.
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