Working conditions of refractory materials for external refining:

1. Long time high temperature and vacuum effect

2. Severe erosion of slag

3. Soaking effect of slag

4. Strong scouring and wear of slag and molten steel

5. Thermal shock due to temperature abrupt change

6. Local overheating and arc radiation

Characteristics of refractory castables for refining outside the furnace:

1. High refractoriness, good stability, and resistance to high temperature and vacuum conditions under out-of-furnace refining conditions

2. Low porosity, high bulk density, compact organization to reduce slag penetration

3. High strength, wear resistance, resistance to erosion and wear of steel slag

4. Good corrosion resistance to acid and alkali slag erosion

5. Good thermal stability, no thermal shock cracking and spalling

6. Non-polluting molten steel, conducive to the purification of molten steel

7. Less environmental pollution