Refractory Technology Which of the following has the lowest electrical resistivity? Graphite Alumina Zircon Fireclay Graphite Alumina Zircon Fireclay ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Firing temperature of magnesite bricks is about __________ °C. 2400-2600 1600-1800 1000-1200 800-1000 2400-2600 1600-1800 1000-1200 800-1000 ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Fireclay refractories All of these Shrink during firing Are not resistant to the action of basic slags Combine with salts (e.g. chlorides sulphates etc.) & bases (e.g. lime, magnesia etc.) forming fusible aluminates silicates etc All of these Shrink during firing Are not resistant to the action of basic slags Combine with salts (e.g. chlorides sulphates etc.) & bases (e.g. lime, magnesia etc.) forming fusible aluminates silicates etc ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology With increase in the density of silica refractories, its Spalling resistance reduces Both A & B Resistance to slag attack increases Neither A nor B Spalling resistance reduces Both A & B Resistance to slag attack increases Neither A nor B ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Quartz is All of these Transformed to crystoballite on heating above 1470°C Stable form of silica upto 870°C Converted to tridymite on firing between 870 to 1470°C All of these Transformed to crystoballite on heating above 1470°C Stable form of silica upto 870°C Converted to tridymite on firing between 870 to 1470°C ANSWER DOWNLOAD EXAMIANS APP
Refractory Technology Fusion point of a basic refractory material is Reduced by the addition of acid oxides Increased by the addition of acid oxides Not affected by the addition of acid oxides Always less than 1000°C Reduced by the addition of acid oxides Increased by the addition of acid oxides Not affected by the addition of acid oxides Always less than 1000°C ANSWER DOWNLOAD EXAMIANS APP