Tinplate and Galvanized Steel Sheet from Coil

Thin steel rusts, so most sheet is coated in continuous lines that run a coil through at speed. Tinplate, the material of food cans, is cold-reduced steel strip about 0.15–0.55 mm thick electroplated with a thin layer of tin, around 1–11 g per square metre; the strip is then heated just past tin's melting point so the coating flows bright, and passivated and oiled. Galvanized sheet is strip run through a bath of molten zinc, the same coating as batch galvanizing done continuously; excess zinc is wiped off as the strip rises, setting the coating thickness.