Refractory Technology Magnesite chrome refractories 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 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 ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Spalling of silica bricks occurs due to abrupt volume changes, when it is cooled below a temperature of __________ °C. 770 70 570 270 770 70 570 270 ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology The linear thermal expansion of __________ bricks upto 1000 °C is very low of the order of ≤ 0.5 percent. Silica Magnesite Fireclay Corundum Silica Magnesite Fireclay Corundum ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Presence of MgO in alumino-silicate refractories __________ its refractoriness. Either A or B; depends on its quantity Lowers Does not affect Increases Either A or B; depends on its quantity Lowers Does not affect Increases ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Refractory materials are never used in the construction of Orton cones Segar cones Ovens & retorts Pressure vessels Orton cones Segar cones Ovens & retorts Pressure vessels ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Spalling resistance of a refractory can not be increased by Increasing its porosity Decreasing its thermal co-efficient of expansion Using a coarser grog during its manufacture Making it denser Increasing its porosity Decreasing its thermal co-efficient of expansion Using a coarser grog during its manufacture Making it denser ANSWER DOWNLOAD EXAMIANS APP