Fused Cast Azs Refractory Blocks

Glass defects such as bubbles, stones, knots and cords originate from many sources, including poor melting and/or refining of glass, as well as refractory quality and degradation. The published literature often cites alumina-zirconia-silica (AZS) refractory exudation as the leading cause of knot and cord defects. However, one study of the origin of knot defects in TV glass showed that AZS refractory exudation is only a short-term source of glass defects, while AZS refractory corrosion, especially in the superstructure, is a more potent and long-term source of defects.