Refractory Technology Silica bricks have low spalling resistance below 600°C, due to its Low refractoriness High co-efficient of expansion upto this temperature Very high thermal conductivity High thermal diffusivity Low refractoriness High co-efficient of expansion upto this temperature Very high thermal conductivity High thermal diffusivity ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Bottom of basic open hearth furnace are constructed of Dead burnt magnesite ramming mass Porous fireclay bricks Silicon carbide bricks Semi-silica bricks Dead burnt magnesite ramming mass Porous fireclay bricks Silicon carbide bricks Semi-silica bricks ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology What is Thoria? Thoria Has high resistance to basic slags All of these 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 Thoria Has high resistance to basic slags All of these 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 ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Quartz is Converted to tridymite on firing between 870 to 1470°C Transformed to crystoballite on heating above 1470°C All of these Stable form of silica upto 870°C Converted to tridymite on firing between 870 to 1470°C Transformed to crystoballite on heating above 1470°C All of these Stable form of silica upto 870°C ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology __________ bricks are used in the burning zone of a cement rotary kiln. High alumina Silicon carbide Fireclay Thoria High alumina Silicon carbide Fireclay Thoria ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Magnesite chrome refractories Are not at all resistant to the corrosive action of iron oxide Have very low (50 kg/cm² ) cold crushing strength (C.C.S.), and can not be used in metalcase form Have very low thermal co-efficient of expansion Have better spalling resistance than chrome magnesite refractories Are not at all resistant to the corrosive action of iron oxide Have very low (50 kg/cm² ) cold crushing strength (C.C.S.), and can not be used in metalcase form Have very low thermal co-efficient of expansion Have better spalling resistance than chrome magnesite refractories ANSWER DOWNLOAD EXAMIANS APP
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