Refractory Technology An insulating refractory brick should have high porosity and low thermal conductivity. Which of the following is not used for inducing porosity in the insulating refractory bricks during its manufacture? Sand Saw dust Chemically prepared foam Cork Sand Saw dust Chemically prepared foam Cork ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Which of the following does not occur during firing/burning of refractories? Decrease in crushing strength Removal of water of hydration Vitrification Development of stable mineral form Decrease in crushing strength Removal of water of hydration Vitrification Development of stable mineral form ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Zirconia refractory Has poor electrical conductivity at high temperature Can not be used as an insulator Does not react with basic slags Is produced from baddeleyite Has poor electrical conductivity at high temperature Can not be used as an insulator Does not react with basic slags Is produced from baddeleyite ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Pyrometric cone equivalent (PCE) value (Segar cone) of 'superduty refractories' is more than 33 which corresponds to a temperature of __________ °C. 1630 1670 1520 1730 1630 1670 1520 1730 ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology __________ is the measure of the strength of refractory under the combined effect of temperature & load. Specific gravity RUL Thermal conductivity Porosity Specific gravity RUL Thermal conductivity Porosity ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Silica refractories Can not be used in the dome of hot blast stoves All of these Crack when subjected to sudden change of temperature Have lower thermal conductivity than fireclay bricks Can not be used in the dome of hot blast stoves All of these Crack when subjected to sudden change of temperature Have lower thermal conductivity than fireclay bricks ANSWER DOWNLOAD EXAMIANS APP