Abstract: A continuous glass-melting tank furnace includes a melting compartment including a melting tank having a lower part, and a superstructure equipped with heaters for receiving and melting raw batch material. Additionally included is a separate refining compartment including a refining tank and a superstructure equipped with a further heater, the refining tank having a lower part and including a transverse sill which divides the refining tank into an upstream refining cell and a downstream refining cell, each of the upstream refining cell and the downstream refining cell having respective upstream ends and downstream ends, and the further heater being arranged to heat melt in the upstream refining cell for creating a spring zone located closer to the downstream end of the upstream refining cell and a circulation of melt in the upstream refining cell which feeds the spring zone.

Abstract: A method for manufacturing glass wherein raw material is fed as a batch to a continuous glass-melting tank furnace, melted in a melting tank and passed to a refining tank via a submerged throat. The melt is heated in the refining tank to de-gas it, and then molten refined glass is delivered to a conditioning tank where it is brought to a desired working temperature. The refining tank is divided into upstream and downstream refining cells by a transverse sill. The melt in the upstream refining cell is heated to create a spring zone located towards the downstream end of that cell and a circulation of melt in that cell which feeds the spring zone.

Abstract: In a method of modifying the light reflecting properties of a glass surface by spraying the surface with an etching solution via a bank of spray nozzles while the nozzles and glass surface are relatively moved past one another, conformity of treatment is improved by effecting such relative passage while the nozzles deliver synchronously oscillating divergent spray cones whose relative spatial relationship and/or amplitude of oscillation is such that in any one cycle the impact zones of the spray cones on the glass surface together cover a continuous band-like impact region extending in a direction across such surface transversely of the direction of relative passage.