METHOD OF CANDIES PRODUCTION Russian patent published in 2009 - IPC C21D8/04 C22C38/42 C22C38/46 

FIELD: metallurgy.

SUBSTANCE: invention concerns rolling mill. Particularly it concerns receiving of candies used at manufacturing of welded pipes for trunk oil and gas pipeline. For cost saving and increasing of candies performance attributes method includes steelmaking, continuous steel casting into slabs, slabs heating up to 1190-1250°C, hot rolling with finish temperature 820-870°C, cooling by water till 500-580°C, candies reeling, rolls cooling with speed 5-20°C/h till the temperature not higher than 100°C. For receiving of slabs there is smelted steel containing wt %: 0.08-0.13 C, 0.50-0.70 Mn, 0.40-0.65 Si, 0.05-0.09 V, 0.015-0.040 Nb, 0.01-0.03 Ti, 0.02-0.05 Al, not more than 0.008 N, not more than 0.3 Cr, not more than 0.3 Ni, not more than 0.2 Cu, not more than 0,005 S, not more than 0.015 P, the rest - Fe, at fulfillment of ratios: C_e=C+Mn/6+(Cr+V+Ti)/5+(Cu+Ni)/15≤0.39%, P_cm=C+(Mn+Cr+Cu)/20+Si/30+Ni/15+V/10≤0.24%, where: C_e - carbon equivalent; P_cm - crack resistance parameter.

EFFECT: cost saving and increasing of candies performance attributes.

3 cl, 2 tbl