Due to having an exceptionally thick and dense refractory lining in the corner regions of an aluminium furnace, smaller heating-up and longer holding phases need to be considered to ensure that those areas are properly heated through. The diffusion of water is heavily slowed down by the thickness of the material in those parts.
Zinc, tin, copper and nickel furnaces
Zinc, tin, copper and nickel furnaces are a special area in the field of dry-outs. These furnaces require a very slow and controlled dry-out phase, given that the region around inductor is lined with concrete. These thick layers of concrete can only be dried very slowly without damaging the material in that process.
Smaller areas can also be dried with heating mats. However, this procedure is very uncommon due to the fact that a complete repair of the furnace usually precedes the dry-out.