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Chemical passivation in CGL

2005

Dear All:

Peace be upon you

Please, which more effective for chemical passivation in C.G.lines with high speed (100 m/mint.), dipping system or spray system.and why?

Best Regards,

Salah El_Deen Salman
Continuous hot dip galvanizing - Cairo, Egypt

Salah, the typical hexavalent chrome passivation used on galvanized surfaces can be apply by either immersion or spray methods. The performance (corrosion protection) of the passivation is a function of the coating weight or amount of passivation applied and not a function of the application method. There are advantages and disadvantages to both application methods. Some of the operational issues related to the application method can impact the performance of the passivation.

Roy Nuss
Trevose, Pennsylvania, USA
2005