Refractory built hot dip galvanizing furnace
The use of refractory materials or ceramic furnaces is usually chosen when dealing with high temperature hot dip galvanizing (around 550 C). This technology originates when new needs appear in the field of zinc based alloying processes for longer lasting protection.
At high temperatures, metals bond instantly and the high fluidity of the molten bath at 550 C helps obtaining a very refined finish, much improved in comparison to the traditional 450 C process, especially with highly reactive Silicon steels. In these furnaces, heat input cannot go through the side walls, as they are purposely built with isolative materials: therefore heat must be generated from top, either by radiation or direct contact.
The most common solutions adopted in the industry are:
1. Top radiation with special burners
2. By contact with induction heaters
3. With immersed pipe burners
Each solution has pros and cons, but Gimeco has widely experimented with all of them and is now proposing the top radiation as the most efficient technology, deploying special burners that would generate flames to be parallel to the top surface of the bath.