Ladle breathable bricks complete the refining of molten steel, the reason and necessity

Blowing rare gas (such as argon) on the bottom of the ladle breathable brick can blow away the gas and solid impurities in the molten steel, which can uniform the composition and temperature of the molten steel, which is of great significance to the refining of molten steel. Out-of-furnace refining is a steelmaking process in which molten steel initially made in a converter, open hearth or electric furnace is transferred to another vessel for refining, also called “secondary steelmaking”.

Blowing rare gas (such as argon) to the bottom of the ladle breathable brick can blow away the gas and solid impurities in the molten steel, which can uniform the composition and temperature of the molten steel, which is of great significance to the refining of molten steel. Out-of-furnace refining is a steelmaking process in which molten steel initially made in a converter, open hearth or electric furnace is transferred to another vessel for refining, also called “secondary steelmaking”. Therefore, the steelmaking process is divided into two steps: primary smelting and refining. Out-of-furnace refining includes: further adjusting and purifying the temperature, composition, gas, harmful elements and inclusions of molten steel in the ladle to achieve the purpose of cleanness, uniformity and stability; promoting the floating of gases and inclusions in the tundish , Stabilize the molten steel temperature during the full casting process.

(Picture) Slit Breathable Brick

The technology and equipment of the refining function outside the furnace are realized: the use of ventilated bricks to pass argon for gas stirring, or electromagnetic stirring; the addition of alloying elements, deoxidizers and slag modifiers through the conveyor system; Solid materials; feeding alloy wires into the ladle; various vacuum degassing technologies; heating molten steel in the ladle furnace; steel flow protection technology.

Commonly used methods of refining outside the furnace can be divided into two types: ladle processing type and ladle refining type. LF furnace refining is one of the main methods of refining outside the furnace. Vacuum treatment is the method of high-quality steel refining currently used. RH and VD are more commonly used. Among them, the AOD method is the production of low-carbon and ultra-low-carbon stainless steel under standard atmospheric pressure, and is a non-vacuum commonly used for smelting stainless steel. The VOD method is an out-of-furnace refining technology for the production of high-chromium stainless steel by blowing oxygen and decarburizing under vacuum conditions and blowing argon with stirring. , It is a non-vacuum and vacuum refining method commonly used in smelting stainless steel.

(Picture) Split Breathable Brick