Indirect fire furnace is used for heating materials and products that produce undesirable byproduct in contact of direct flame. In addition, heating at such high temperature would result in corrosive environments which is also Detrimental. In such cases, the furnaces utilize the carefully insulated containers used for heating. The materials are put in heat conductive container outside burners and are heated by contact with combustion products.
Muffle furnaces are widely used for: