COATED METAL SHEET, METHOD TO PROVIDE SUCH A COATED METAL SHEET, AND HOT DIP GALVANIZING DEVICE TO MANUFACTURE SUCH A COATED METAL SHEET

摘要

Method of providing a coating on a metal sheet, wherein a cold rolled metal sheet is subjected to a hot dip galvanizing operation to provide a metal coating on the metal sheet, which hot dip galvanizing operation comprises guiding the metal sheet through a liquid bath of the metal coating with at least one stabilization roll provided at a predefined depth (Depth) below surface level of the liquid bath, and wiping the metal coating that is provided on the metal sheet with at least one gas knife having an outlet to project wiping gas on the metal coating on the metal sheet that passes along the gas knife, wherein a distance (D) of the at least one gas knife to the passing metal sheet and a height (H) of the at least one gas knife above the liquid bath of the metal coating are selected at values so as to satisfy a formula X = (Wsa - 0.1395) / 0.0016, wherein X = D*ln(H*Depth) and wherein Wsa is selected at a value representing a targeted maximum waviness.