The invention relates to a thermal annealing acid-washing method of a stainless steel wide and
thick plate coil, which comprises the following steps of: uncoiling an inlet of the stainless steel wide and
thick plate coil,
welding, continuously annealing, breaking scales shot-blasting, acid-washing, flattening, and coiling an outlet of the stainless steel wide and
thick plate coil, wherein the groove depth of a
welding girder is 1.0-1.5mm; 3-6 annealing furnaces with the total length of 75-150m are adopted in
continuous annealing, the annealing temperature is 1000-1150 DEG C, and the annealing time is 10-20min; in the shot blasting process, the blasting speed is 1500-2250rpm, the blasting quantity is 600-100kg / min, and the blasting particle has a grain size of 0.5-0.7mm; and in the
acid washing step,
acid washing is carried out by adopting mixed acid of
hydrofluoric acid and
nitric acid in 3-6 sections of grooves. By adopting the method, in a
continuous annealing acid-washing process of the stainless steel wide and thick plate coil, problems of strip breakage, poor material property, poor surface quality, reeling off, surface
scratching and the like can be avoided as much as possible.