Manufacturing equipment for galvanized steel sheet, and manufacturing method of galvanized steel sheet

A manufacturing method of a galvanized steel sheet, the manufacturing method comprising:

• circulating a coating bath which is a molten metal including a molten zinc and a molten aluminum in order of a coating tub, a separating tub, and an adjusting tub;
• coating a steel sheet which is dipped in the coating bath at the coating tub in which the coating bath transferred from the adjusting tub is stored at a predetermined bath temperature T1;
• separating by a flotation a top-dross which is precipitated at the separating tub in which the coating bath transferred from the coating tub to the separating tub is stored at a bath temperature T2 which is lower than the bath temperature T1 of the coating tub;
• and
• dissolving a residual dross at the adjusting tub in which the coating bath transferred from the separating tub is stored at a bath temperature T3 which is higher than the bath temperature T2 of the separating tub.