General Introduction for Hot dipped galvanizing production line work flow

Hot dipped Galvanizing consists of coating steel with zinc in order to protect it from corrosion. Before steel can be galvanized, they undergo a pre-treatment in order to ensure that the steel are free from any surface oxides as they enter the molten zinc coating bath (Galvanizing kettle). This is done by removing the oil from the steel (in degreasing bath) and then removing the rust from the surface of the steel ( in pickling bath).

The steel is then dipped into a zinc bath (450C to 460C) to be galvanized. The melting zinc on the strip suface will be cooled and solidified through air cooling in the cooling tower.

Finally the galvanised steel are dipped into a water quenching tank in order to further cool the steel from about 150c to 40c.

It is possible to make galvanised steel more durably by chromating it. Approximately 50% of the galvsnised steel production output will receive chromate passivation treatment after quenching: the galvanised steel will be sprayed with a chrome solution.

After galvanizing and chromating, the steel are cut to achieve the desired size and weight and transported to the storage yard.