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? Saw dust Chemically prepared foam Sand Cork Saw dust Chemically prepared foam Sand Cork ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Refractoriness of a typical silica brick corresponds to Segar cone number, '32', which is equivalent to a temperature of __________ °C. 1915 1380 1710 1520 1915 1380 1710 1520 ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Fusion point of a basic refractory material is Not affected by the addition of acid oxides Increased by the addition of acid oxides Always less than 1000°C Reduced by the addition of acid oxides Not affected by the addition of acid oxides Increased by the addition of acid oxides Always less than 1000°C Reduced by the addition of acid oxides ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Conversion of silica mineral to cristobalite is accompanied by reduction in its Both A & B Neither A nor B Specific gravity Volume Both A & B Neither A nor B Specific gravity Volume ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Spalling resistance of a refractory can not be increased by Making it denser Decreasing its thermal co-efficient of expansion Using a coarser grog during its manufacture Increasing its porosity Making it denser Decreasing its thermal co-efficient of expansion Using a coarser grog during its manufacture Increasing its porosity ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Fusion temperature of pure silica (SiO₂) is __________ °C. 2570 1715 2800 1350 2570 1715 2800 1350 ANSWER DOWNLOAD EXAMIANS APP