Glass fibre production - in crucible with loose bottom plate both of which float in glass permeated lining

摘要

Glass fibre making plant comprises a glass melting vessel consisting of a sleeve with open bottom standing on a perforated bottom plate through which the molten glass passes to form a bundle of glass fibres on solidification. The whole is surrounded and held by a thermal insulation packing which is permeable to molten glass, which passes into it through the gap between the sleeve and the bottom plate but is thick enough to ascertain that glass penetrating it solidifies before reaching the exterior surfaces of the insulation. The packing pref. includes impermeable flanges surrounding the bottom outlet underneath the plate to prevent flow of melt into this gap through the lining. The system does away with the need for a seal between the bottom plate and the crucible walls and ensures that the crucible unit floats in an envelope of molten glass.