Magnesia Spinel Refractory Blocks
Pre-fired blocks combining magnesia with spinel (MgAl2O4) where MgO exceeds 50%, used in cement kiln burning zones. Offers superior thermal spalling resistance. Falls under HTS 6902.10.50.00 for magnesium-dominant refractory constructional goods.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If alumina-spinel with Al2O3>50%
Alumina-dominant spinel refractories classify under high-alumina provisions.
If specifically industrial furnace parts
Parts of furnaces may classify as machinery parts if not general construction goods.
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Import Tips & Compliance
• Document spinel content calculation method as it contributes to MgO equivalence
• Avoid bundling with metal casings which could trigger Chapter 73 classification
• Certify as finished refractory goods, not parts for further assembly
Related Products under HTS 6902.10.50.00
Magnesia-Herringbone Refractory Bricks
Herringbone-patterned magnesia bricks with >50% MgO for improved gas flow in tunnel kilns and reheating furnaces. The angled design prevents brick movement under thermal cycling. HTS 6902.10.50.00 classification for magnesium refractory bricks.
Rebonded Fused Magnesia Chrome Bricks
Ultra-high purity bricks made from rebonded fused magnesia-chrome grains with aggregate >50% MgO/Cr2O3, for electric arc furnace roofs. Exceptional service life in severe conditions. Covered by HTS 6902.10.50.00 as premium refractory bricks.
High Purity Magnesia Refractory Shapes
Custom-shaped refractory components with 95%+ MgO content for specialized furnace zones like ladle impact pads. Precision fired to maintain dimensional stability. HTS 6902.10.50.00 for high magnesium oxide refractory goods.
Calcium Ferrite Refractory Bricks
Refractory bricks incorporating calcium ferrite phases with >50% CaO equivalent for waste incinerator linings. Resistant to alkali corrosion from flue gases. Classifies HTS 6902.10.50.00 for high calcium oxide refractories.
Magnesia-Dolomite Composite Refractory Blocks
Composite blocks blending magnesia and dead-burned dolomite achieving >50% combined MgO/CaO for basic oxygen furnace linings. Balanced chemistry for steelmaking slags. HTS 6902.10.50.00 classification applies.
Chromium-Corundum Refractory Bricks
High-chrome corundum bricks with Cr2O3>50% for glass furnace superstructures resisting batch carryover. Dense microstructure prevents glass penetration. Covered by HTS 6902.10.50.00 for chromium oxide dominant refractories.