METHOD OF MERCHANT SHAPES PRODUCTION Russian patent published in 2001 - IPC

FIELD: rolling; applicable in hot rolling of merchant shapes including round bars and strips. SUBSTANCE: steel strips are produced by heating and machining. Steel contains, wt.%: carbon, 0.22; silicon, 0.4; and manganese, 1.1. Rolling is carried out with regulated rolling end temperature Tr.e. which is determined by relation Tr.e. = 1156 C^0,0545 + 2 C. Cooling is effected in three stages. In this case cooling rate from Tr.e. to temperature of beginning of regulated cooling Tb.r.c. is not regulated. Cooling from Tb. r. c. = 115 C + 908 C to temperature interval T1-T2 = - 809.6-164.3 C -, where = 883-600 C with carbon C content in steel ≅ 0.11%, = 842.2-65.8C with 0.22 C ≥C> 0.11% and = 854.3-204.5C with carbon content above 0.22% and 22 Mn+2.7 and = 28 Mn+4.4 with manganese content within ≅ 0.7%, = 72 Mn - 32; and = 70 Mn-25 with 1.0 ≥ Mn > 0.7%; = 6.6 Mn + 34.6 and = 7.8 Mn +38.5 with manganese content above 1.0% and = = 5.3 Si^0,4 C cooling is carried out at rate V1 ≥ 24.5/C^0,58 C/s, then metal is cooled at rate V2 ≅ 28.5-15 Mn with manganese content within 0.5%; V2 ≅ 28,5 15 Mn with manganese content ≅ 0,5%, v2 ≅22-2 Mn with 0.5 <Mn ≅ 1.2% and V2 ≅ 30.1-8.9 Mn C/s with manganese content above 1.2% to temperature of end of regulated cooling Te.r.c. ≅ 480/C^0,046 C. EFFECT: higher efficiency. 1 cl, 1 tbl