Chapter 4 REFRACTORY MATERIALS MCQs 10 min Score: 0 Attempted: 0/10 Subscribe 1. . Silica refractories are not used in: (A) Coke oven walls (B) Beehive coke ovens (C) Dome and upper portion of B.F. stoves (D) Open hearth furnaceShow All Answers 2. . Si percentage in silica refractories used in the walls of coke oven is about: (A) 45 (B) 60 (C) 80 (D) 95Show All Answers 3. . Porosity of silica bricks varies from: (A) 5 to 10 (B) 20 to 30 (C) 45 to 60 (D) 60 to 75Show All Answers 4. . Chrome magnesite bricks are: (A) Acidic in nature (B) Neutral in nature (C) Having higher RUL than silica bricks (D) Made by mixing 30% Chromite and 70% PericlaseShow All Answers 5. . Alumina-graphite bricks are used for lining the: (A) Slide gate in teeming ladles (B) Continuous casting systems (C) Both (a) and (b) (D) Neither (a) nor (b)Show All Answers 6. . Maximum shrinkage in volume during firing of dried refractories may be as high as: (A) 10 (B) 15 (C) 20 (D) 30Show All Answers 7. . The main raw material for manufacture of silicon carbide refractories is: (A) Corundum (B) Carborundum (C) Bauxite (D) PericlaseShow All Answers 8. . Which consumes the maximum tonnage of refractories annually in an integrated steel plant? (A) Soaking pits (B) Reheating furnace (C) L.D. converter (D) Rotary lime kilnShow All Answers 9. . Upper portion of hot metal mixer lined with mullite bricks helps in resisting: (A) Washing action of metal (B) Corrosion by slag (C) Both (a) & (b) (D) Neither (a) nor (b)Show All Answers 10. . Lower part of hot metal mixer is lined with: (A) Superduty fireclay (B) High alumina (C) Silica (D) CarborandumShow All Answers
