RADIATION TARGET STRUCTURE AND USE TO COOL MOLTEN GLASS

Adjustable, thin, fluid-cooled radiation targets are provided for selectively cooling the center surface portion of a molten glass stream in a glass making furnace forehearth. These radiation targets, which are generally of truncated triangular shape when viewed from an end in a direction parallel to the glass stream, may be arranged in tandem along the glass stream center surface portion, with each target having a plurality of connected wall panels defining a low-profile-closed chamber including a top portion spaced a substantial distance below the forehearth roof and inwardly converging side portions spaced a substantial distance from the glass stream edges. A plurality of spaced baffles within the closed chamber, and together therewith, define a circuitous fluid passageway having fluid entry and exit ports on the opposite ends thereof. Means are provided for supplying and removing a cooling fluid and further means control the degree of cooling imparted by the radiation target. A method for cooling the glass surface center portion includes positioning the radiation targets within a preselected region above the glass surface center portion and controlling the degree of cooling of the radiation targets.