PROCEDURE FOR PRODUCTION OF STRIPS IN REELS Russian patent published in 2011 - IPC C21D8/02 C22C38/20 

FIELD: metallurgy.

SUBSTANCE: produced slab is heated to temperature of austenisation. Further, slab is rough and finish hot rolled and cooled with water with acceleration to temperature of reeling 500÷600°C. Winding into a reel and forced cooling are performed at rate 5÷20°C/h. Also, upon completion of rough rolling a breakdown bar is cooled to temperature 920÷980°C. Finish rolling is performed with summary reduction not less, than 65% and temperature of finish rolling above A_r3. Strip accelerated cooling with water is performed in two stages, first at rate of 5÷8°C/sec to temperature 580÷620°C, further at rate 0.5÷1.5°C/sec to temperature of reeling. Slabs are produced of steel containing the following chemical composition, wt %: 0.015÷0.090 C; 1.2÷1.8 Mn; 0.1÷0.5 Si; 0.01÷0.10 Nb; 0.01÷0.07 Al; Mo≤0.3; Cr≤0.3; Ni≤0.3; Cu≤0.3; V≤0.12; S≤0.010; P≤0.015; 0.003÷0.012 N; Fe - the rest.

EFFECT: raised viscous and strength properties of strip due to creation of ferrite-bainitic micro-structure.

2 cl, 3 tbl