Glass melting furnace - where hearth is formed by metal pipes through which coolant flows, so solidified crust of glass separates melt from pipes

摘要

The furnace includes a tanl or sump contg. the molten glass, which is heated by burners creating gases which flow up an exhaust gas duct located above an inlet for the batch. The based and walls of the sump, and at least part of the exhaust gas duct are formed by metal pipes through which a coolant flows, so the pipes are covered by a solidified crust of glass. The surfaces of the tubes adjacent to the molten glass are pref. provided with longitudinal ribs, and/or a coating of Al, and/or glass panels. The furnace uses no refractory lining which can contaminate the melt, so glass with a very high purity is obtd.