METHOD OF ANNEALING WITH SUBSEQUENT ETCHING OF STRIP HOT-ROLLED STAINLESS STEEL AND EQUIPMENT FOR IMPLEMENTING METHOD Russian patent published in 2025 - IPC C23G3/02 C21D9/56 C21D1/26 C23G1/08 

FIELD: metallurgy.

SUBSTANCE: method of annealing with subsequent etching of strip hot-rolled stainless steel includes annealing, subsequent etching by means of a cascade overflow system, washing in a multistage washing system, and then drying and winding, at that, at the etching step, the total content of iron in Fe²⁺ and Fe³⁺ in the cascade overflow system of continuous etching, it is controlled by the method of adding a multicomponent weak acid on the line, as well as by the method of circulation filtration and separation. Equipment for annealing and subsequent etching of strip hot-rolled stainless steel contains a supervisory control system and an oxidation potential sensor, this supervisory control system is connected to each acid bath of the continuous etching cascade overflow system, the oxidation-reduction characteristics of the etching medium in the continuous etching cascade overflow baths are connected to an automatic valve for adding an oxidant, oxidation potential sensor is used to determine the oxidation-reduction characteristics of the etching medium by determining the oxidation-reduction potential of the acid solution in cascade overflow baths of continuous etching, and a dispatcher control system is used to add an oxidant to corresponding baths for etching of cascade overflow baths of continuous etching.

EFFECT: development of efficient method of annealing with subsequent etching of strip hot-rolled stainless steel.

4 cl, 1 dwg