METHOD OF PRODUCTION OF SHEET COLD ROLLED TUBULAR STEEL Russian patent published in 2009 - IPC B21B1/28 

FIELD: metallurgy.

SUBSTANCE: disclosed method consists in etching hot rolled bands of 22GYU grade steel, in their cold rolling with specified reduction, in annealing of rolls and in band pinch-rolling Improvement of such properties of steel as, for example welding characteristics, is facilitated due to rate of etching not exceeding 3.0 m/s in hydrochloric acid solution of 40…50 g/l concentration, to value of total reduction at rolling accepted within ranges 49.51% with decrease of absolute reduction during rolling, to annealing carried out in bell furnaces with a protective hydrogen atmosphere and to conditioning from 300°C up to 400°C temperature within 5 hours and 660°C temperature at the end of annealing, while pinch- rolling of annealed bands is carried out with reduction of 1.8…2.5 %.

EFFECT: upgraded quality of consumer properties of 22GYU steel with thickness 1,5 mm.

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