Refractory Technology What is Thoria? Which is expensive & radioactive, is used in crucibles for melting high purity metals All of these Thoria Has high resistance to basic slags Thoria Has high fusion temperature (> 3000°C) but poor resistance to thermal shock Which is expensive & radioactive, is used in crucibles for melting high purity metals All of these Thoria Has high resistance to basic slags Thoria Has high fusion temperature (> 3000°C) but poor resistance to thermal shock ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Lower wall courses of soaking pits are made of __________ bricks to avoid the action of molten slag & scale. Lowduty fireclay Silicon carbide Silica Chrome or magnesite Lowduty fireclay Silicon carbide Silica Chrome or magnesite ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Lower part of hot metal mixer are lined with __________ bricks. Superduty fireclay Carborundum Silica High alumina Superduty fireclay Carborundum Silica High alumina ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Zircon refractories have All of these Low co-efficient of expansion High RUL (1600°C) and refractoriness (> 2000°C) High spalling resistance All of these Low co-efficient of expansion High RUL (1600°C) and refractoriness (> 2000°C) High spalling resistance ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Thermal conductivity of refractory bricks Increases with decrease in porosity Is independent of its porosity and is maximum for insulating bricks Increases with the amount of air entrapped in pores Decreases with decreases in porosity Increases with decrease in porosity Is independent of its porosity and is maximum for insulating bricks Increases with the amount of air entrapped in pores Decreases with decreases in porosity ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Carborundum used for making crucibles for melting non-ferrous metals is chemically Silicon carbide Crystalline magnesia Zirconium sulphate Silicon nitride Silicon carbide Crystalline magnesia Zirconium sulphate Silicon nitride ANSWER DOWNLOAD EXAMIANS APP