Corundum castable for ladle

Corundum castables are high-alumina refractory castables containing a significant amount of corundum (aluminum oxide, Al?O?) as the primary component. These castables are widely used in the linings of steel ladles in the iron and steel industry due to their excellent properties, such as high-temperature resistance, mechanical strength, and chemical inertness.

1.Properties of Corundum Castables for Ladles

Corundum castables are chosen for ladle linings because they possess several key properties that make them suitable for handling molten steel:

High Alumina Content:With alumina content typically above 90%, corundum castables offer outstanding resistance to high temperatures and corrosive slags.

Excellent Thermal Resistance:They can withstand temperatures up to 1800°C, making them suitable for ladles, which encounter extreme heat from molten steel.

High Mechanical Strength:Corundum castables have high compressive and mechanical strength, essential for handling the mechanical stress during molten steel transport and pouring.

Resistance to Erosion and Corrosion:Due to their high alumina content, corundum castables are resistant to chemical corrosion by basic slags and molten metal, which is crucial for ladle linings that are in direct contact with molten steel.

Thermal Shock Resistance:Enhanced resistance to thermal cycling reduces the risk of spalling, cracking, and premature failure, which is critical for ladles that frequently undergo heating and cooling.

2.Advantages of Using Corundum Castables in Ladles

Improved Service Life:Due to their high resistance to chemical attack, erosion, and mechanical wear, corundum castables can significantly extend the service life of ladle linings.

Ease of Installation:As a castable, corundum can be poured or pumped into place, allowing for easier application in complex ladle geometries compared to traditional refractory bricks.

Lower Maintenance:Longer service life reduces the frequency of ladle relining, resulting in reduced maintenance costs and downtime for steel production.

3.Composition of Corundum Castables

Corundum castables for ladles typically include:

Corundum Aggregates:Comprising the main component, these high-purity alumina aggregates provide the primary properties of the castable.

Fine Powder:Fine alumina powder enhances the castable's packing density and strength.

Binders:Hydraulic or chemical binders, such as calcium aluminate cement or phosphates, help set and bond the castable upon curing.

Additives:Dispersants, deflocculants, and anti-cracking agents improve workability, flow, and mechanical strength.

4.Installation and Use

Casting:Corundum castables are mixed with water (or another liquid binder) to form a slurry, which is then poured or vibrated into molds lining the ladle.

Drying and Firing:After installation, the castable is dried to remove excess moisture and then fired to high temperatures to develop its final properties. Proper drying and firing are crucial to ensure optimal performance and prevent cracks.

5.Applications

While corundum castables are primarily used for ladle linings, they are also suitable for other high-temperature areas in steelmaking, such as:Tundishes、Troughs in blast furnaces、Tap hole blocks in electric arc furnaces (EAFs)

Corundum castables offer excellent thermal, mechanical, and chemical properties, making them ideal for use in ladle linings in the iron and steel industry. They enhance the efficiency, longevity, and safety of steelmaking operations.