Application Of Corundum Spinel Castable - Insulation Refractory Product

Application of Corundum Spinel Castable

One of the primary applications of corundum spinel castables is in the bottom of steel ladles, where they provide high-temperature resistance, erosion resistance, spalling resistance, penetration resistance, and ensure no contamination of molten steel. The main raw materials used in these castables include corundum spinel sand, tabular corundum, added micropowders, and binders.

Main Features:

1. Excellent thermal shock stability and spalling resistance.

2. High resistance to molten steel corrosion.

3. Superior erosion resistance.

Main Application Scenarios:

Ladle working lining: Used as the bottom working layer in electric furnace steelmaking ladles, replacing traditional alumina-magnesia carbon bricks. It withstands high-temperature slag erosion and mechanical wear.

Converter slag line: Applied in the slag line area of converters. Slag resistance is enhanced through pre-synthesized or in-situ formation of magnesium aluminum spinel.

High-temperature kilns: Suitable for high-temperature industrial equipment such as carbon black reaction furnaces and coal-water slurry gasification furnaces, with service temperatures exceeding 2000 °C.

Performance Advantages:

Strong slag erosion resistance: Spinel and corundum aggregates effectively resist slag penetration, extending equipment service life.

Excellent high-temperature stability: Stable phases such as calcium hexaaluminate (CA₆) and magnesium aluminum spinel (MA) form at high temperatures, enhancing structural strength.

High volume stability: Carefully controlled particle size distribution and additives minimize cracking caused by thermal expansion.

Application Challenges:

Balancing thermal shock resistance: High-density materials tend to exhibit reduced thermal shock resistance, which can be mitigated by optimizing the raw material ratio.

Anti-spalling performance optimization: Anti-spalling agents such as metallic aluminum powder and organic fibers can raise the anti-spalling temperature to 900 °C. However, excessive addition should be avoided to prevent structural damage.

Cost and construction: Precise control of water addition (5%–5.5%) and mixing time (3–5 minutes) is essential to ensure proper fluidity and density.