The REVIMAC E-FOREHEARTH has been developed and has given demonstration of its capability to grant glass conditioning control above the standard, as required by NNPB process operation. One of the main features is : Original Refractory Superstructure design • Dual cooling system: direct cooling on to the glass surface and/or indirect cooling by conveying the air through the overhead longitudinal tunnel. • Possible use of either one of the cooling methods, or the combination of the two applied simultaneously , offering moreover independent adjustment of the opening of the two separate cylindrical exhaust stacks; • Structural strength is granted by the newly designed roof blocks, supported by 3 lintels (architraves) in each zone with laterals members resting on the ticker and taller burner blocks • The combination of the several forces applied ensures that the refractory blocks stay put in position and do not fall down inside the channel even in case of severe breakage. Glass contact channel blocks material with a 99% content of alumina have proven greatly successful over the years.
The New Revimac Coloring System for glass conditioning Forehearths, enables the feeding, melting and mixing of the colorant before the final cooling and conditioning of glass. The installation of such a system determines an additional length of the forehearth from 3 up to 6 meters approximately.
It is basically subdivided into the following zones : Pre-heating zone: its function is to maintain a regular glass temperature that enables the proper melting of the color concentrate. The needed temperature is reached by means of a set of double-stack burners and controlled typically through an optical pyrometer. Melt zone: this must be long enough to allow sufficient time for the colorant to melt and to exhaust the combustion gases on the glass surface before stirring. Stirrers zone: it is required to ensure proper mixing of the colored glass.