Device and method for melting vitrifiable materials

A device for preparing glass fibers from a final flow of molten glass derived from melting batch material(s) that combines at least two separate melting modules that can both contribute to produce said molten batch materials together or alternately, comprising:

• a module A(1) which is predominantly fitted with heating means in the form of crown burners and/or submerged electrodes and can be fed with batch materials;
• a module B(2) which is predominantly fitted with heating means in the form of (a) submerged burner(s) and can be fed with batch materials;
• wherein the melting module A(1) and the melting module B(2) both open directly or via transfer ducts into a mixing module C(3) which is fitted with at least one stirring and/or heating means, and
• wherein the mixing module C(3) opens directly into a duct feeding fiber-forming members.