Low-Alpha Technology- A Unique Way to Utilize Magnesia-Carbon Refractories in Steel Ladles

摘要

Magnesia-Carbon refractories are being used as working lining of different vessels like BOF, EAF, EOF, Conarc Furnace, ladle . in steel plant operation. MgO-C product has got high resistance to corrosion by slag and metal and limited resistance to hermal cycling. It has been observed frequently that the lifetime of the same is guided mostly by thermo-mechanical character not corrosion due to variation in operation. Hence, MgO-C refractories can be best utilized if resistance to thermal spoiling is without disturbing other properties. Thermal expansion co-efficient ofPericlase at 1000 deg C is 1.4%, which is highest mong all refractory oxides being used for high temperature application. High thermal expansion leads to poor resistance to hermal spoiling for obvious reason, which finally results in crack formation, brick to brick joint opening, cobblestone wear etc. use. Among all the vessels being used in steel plants, ladle working lining is mostly exposed to melt during an operation in to others due to less online maintenance practice like slag splashing in BOF, gunning/fettling in EAF/EOF/Conarc hence the effect of poor resistance to thermal spoiling affects much in ladle operation. The present work of development Low-Alpha technology shows an innovative way to reduce the thermal expansion and thus thermo-mechanical stress with aim to improve service performance by imparting mechanical flexibility in use. Co-efficient of thermal expansion could be by 30% and Young’s modulus by 50% than the original brands with the help of our Low-Alpha technology, which has thermo-mechanical flexibility and ultimately user-friendly MgO-C product. High thermal stability, high corrosion , and high mechanical flexibility are the key properties of the developed product and the same has been widely used steel ladles around the globe. This paper has also demonstrated an updated status of the performance of MgO-C refractories Low-Alpha technology in steel ladles, which was found to be highly encouraging. An attempt has been made to correlate high performance of the product with its thermo-mechanical properties.