ANNEALING METHOD OF LOW-CARBON SHEET METAL IN BELL FURNACES Russian patent published in 2009 - IPC C21D9/48 C21D9/663 C21D1/26 

FIELD: metallurgy.

SUBSTANCE: invention relates to ferrous metallurgy, particularly to thermal treatment of cold-rolled low-carbon rolling, provided for complex and extradeep drawing (CD and ED). For achievement of technical result it is implemented heating of reels of cold-rolled strips in bell furnace with protective atmosphere at specified heating rate up to temperature of recrystallisation annealing, isolation at this temperature and cooling, herewith heating from the temperature 380°C up to temperature for 150°C lower the recrystallisation temperature is implemented at a rate 100°/hour and it is implemented isolation at this temperature, herewith isolation time is defined by ratio: τ=0.088m+1.25b+4, where m - mass of bottom reel in stack, t, b-strip width, mm.

EFFECT: obtaining strip with high quality of surface finishing, complex of mechanical properties, and also increasing in productivity of bell furnace and reduction of production expenditures.

1 ex, 1 dwg