As a glass plant engineer or procurement manager, you know that every unplanned furnace shutdown costs thousands in lost production and repair expenses. One of the most overlooked yet impactful factors affecting your furnace’s performance is refractory selection—specifically, the Na₂O content in electric fused AZS (Alumina-Zirconia-Silica) bricks.
In float glass manufacturing, molten glass interacts continuously with the refractory lining. High Na₂O levels (>1.35%) accelerate chemical attack by forming low-melting-point glass phases that penetrate grain boundaries and weaken structural integrity. According to industry data from the International Commission on Glass (ICG), furnaces using standard AZS with Na₂O+K₂O >1.5% experience up to 30% higher erosion rates after just 18 months of operation compared to low-sodium alternatives.
| Refractory Type | Na₂O + K₂O (%) | Glass Phase Formation Temp (°C) | Avg. Erosion Rate (mm/year) |
|---|---|---|---|
| Standard AZS 36 | 1.7–2.0% | ~1300°C | 1.8–2.5 mm/yr |
| TY-AZS36D (Low-Na₂O) | ≤1.35% | ≥1400°C | 0.6–1.0 mm/yr |
That’s not just a difference—it’s a game-changer. With TY-AZS36D, you reduce corrosion-related maintenance by over 60%, minimize crystal formation at high temperatures, and significantly lower the risk of bubble defects in finished glass sheets.
A major flat glass producer in Thailand switched from conventional AZS to TY-AZS36D in their 120-ton/day furnace. Within 10 months:
These results weren’t luck—they were engineered. The key? Controlling the alkali content below 1.35%. This ensures better resistance to both chemical attack and mechanical stress under extreme conditions.
Not all glass compositions are equal. If your product is sodium-calcium-silicate-based (common in float glass), prioritize refractories with:
For longer runs (>3 years), consider upgrading to premium grades like TY-AZS36D or even TY-AZS40D if operating above 1550°C. Matching material specs to your specific temperature profile, glass chemistry, and expected runtime prevents premature failure—and saves money.
Pro Tip: Always request certified lab reports showing actual Na₂O levels—not just nominal values. Some suppliers may label products as “low sodium” without verifying trace elements. Verify it yourself.
You don’t need to guess when selecting refractories anymore. With clear metrics like glass phase stability, erosion rates, and real-world case studies, choosing TY-AZS36D isn’t just smart—it’s essential for modern float glass operations.
