Patent ID: 8341978

Claim:
A process for producing glass fibers from raw glass batch in a refractory lined glass melter, the process comprising the steps of: charging raw glass batch to the melting zone of the glass melter, the glass batch comprising: about 60.5 to about 70.5 weight percent SiO 2 ; about 10 to about 24.5 weight percent Al 2 O 3 ; about 11.96 to about 20.0 weight percent RO, where RO equals the sum of MgO, CaO, SrO and BaO in the batch composition, wherein the amount of MgO in said alkaline earth oxide comprises at least 5 weight percent of said batch composition and the amount of CaO in said alkaline earth oxide comprises at least 6.96 weight percent of said batch composition; and 0 to about 3 weight percent alkali metal oxides; heating the glass batch to a forming temperature in excess of the liquidus temperature of a resulting glass to form a fiberizable molten glass; and fiberizing said molten glass to produce glass fibers having no a fiberizing temperature of less than about 2650° F.