Application of Magnesia Carbon Brick in Converter Steelmaking

The converter uses molten iron and scrap steel as raw materials, and removes carbon by slagging, oxygen blowing, etc., to obtain molten steel that meets the requirements. Its smelting steel is different, and the service life of the lining is different. If the furnace is large and only carbon steel is smelted, the smelting temperature is lower and the composition of the slag is relatively constant. Therefore, the service life is higher. And if there is dephosphorization, the service life will drop a lot.

In recent years, converter smelting technology has also been greatly developed, especially the development of converter re-blowing technology, that is, the supply of gas bricks at the bottom of the converter, blowing nitrogen, carbon dioxide, argon or oxygen into the furnace through the gas supply bricks. It strengthens the molten pool agitation and improves the smelting reaction, which shortens the steelmaking time, improves the quality of the molten steel and reduces the cost of steelmaking. However, the double blow also accelerates the erosion of the lining refractory.

 

The various parts of the converter are eroded by different conditions. In the furnace cap, the slag is eroded, the airflow is washed, that is, the oxidation of the magnesia carbon brick and the mechanical damage when cleaning the furnace cap. Therefore, the furnace cap should use high-oxidation and reluctant magnesia carbon bricks. For the trunnion area of ​​the converter, it is seriously eroded by the slag, the airflow is washed and oxidized, and it is subjected to mechanical stress, which is particularly difficult to repair. Therefore, high-strength and corrosion-resistant magnesia carbon brick with a carbon content of 16-18% should be selected. Due to the erosion of slag, high-quality and high-resistance magnesia carbon bricks are selected.

For the loading side, in addition to the erosion of steel and slag, it is also subjected to impact and erosion when loading molten iron and scrap steel materials, and this is very serious, so high-strength magnesia carbon bricks with high corrosion resistance and thermal shock resistance are used in this area. .

 

The tapping port is subjected to oxidation, slag corrosion, rapid temperature change, molten steel scouring, etc., so high-strength, high-oxidation-resistant magnesia carbon bricks are used. To improve the service life of the converter, lining refractory is an important factor affecting the service life, but the operating conditions are more important factors, and the good conditions of use are the basis for the high life of the lining.