Hot-dip zinc coated steel plate DX54D+Z,DX54D,DX54D+ZF generally receive surface protection at rolling plants.The period of protection afforded depands on the outside atmospheric conditions.These surface protection for galvanized steel plate and coil DX54D+Z,DX54D,DX54D+ZF including Chemical passivation,Oiling,Chemical passivation and oiling,sealed,phosphated and untreated.Generally the galvanized steel sheet DX54D+Z,DX54D,DX54D+ZF shall be done surface treatment after rolling,if when customers indicate in their purchase order without surface treatment terms,we can delivery these galvanized steel materials under untreated condition.In this case,there is increased risk of atmospheric corrision.