Method for producing tinplate substrate based on cover annealing technology

The invention discloses a method for producing a tinplate substrate based on a cover annealing technology. The method comprises the following steps that a cold-rolled sheet with the thickness of 0.414-0.356 mm and the width of 800-900 mm is subjected to degreasing cleaning, cover annealing and leveling secondary down-pressing treatment so as to obtain the secondary cold-rolled tinplate substrate,wherein the hot spot of cover annealing is controlled to be 600 DEG C, and the cold spot is controlled to be 570 DEG C. According to the method, leveling secondary down-pressing treatment is carried out through a temper mill, the leveling secondary down-pressing rate is controlled to be 10-23%, a first machine frame of the temper mill adopts a continuously-variable-convexity roller profile with the roller surface roughness of 0.4 micron, a second machine frame of the temper mill adopts a double-sided chamfered flat roller profile with the roller surface roughness of 2.0 microns, and thereforeby means of the technical