Refractory Technology Objective Questions and Answers - Set 01 - ObjectiveBooks

Refractory Technology Objective Questions and Answers - Set 01

Practice Test: Question Set - 01

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 furnace roof

2. Si percentage in silica refractories used in the walls of coke oven is about
    (A) 45
    (B) 60
    (C) 80
    (D) 95

3. Porosity of silica bricks varies from __________ percent.
    (A) 5 to 10
    (B) 20 to 30
    (C) 45 to 60
    (D) 60 to 75

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% Periclase

5. Alumina-graphite bricks are used for lining the
    (A) Slide gate in teeming laddies
    (B) Continuous casting systems
    (C) Both (a) and (b)
    (D) Neither (a) nor (b)

6. Maximum shrinkage in volume occurring during burning/firing of dried refractories may be as high as __________ percent.
    (A) 10
    (B) 15
    (C) 20
    (D) 30

7. The main raw material for manufacture of silicon carbide refractories is
    (A) Corundum
    (B) Carborundum
    (C) Bauxite
    (D) Periclase

8. Which of the following 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 kiln

9. Upper portion of hot metal mixer are lined with mullite bricks, which helps in resisting the
    (A) Washing action of metal
    (B) Corrosion by layer of slag
    (C) Both (a) & (b)
    (D) Neither (a) nor (b)

10. Lower part of hot metal mixer are lined with __________ bricks.
    (A) Superduty fireclay
    (B) High alumina
    (C) Silica
    (D) Carborundum

11. High density refractory bricks have lower
    (A) Spalling resistance
    (B) Thermal conductivity
    (C) Fusion point
    (D) Slag penetration resistance

12. Bauxite calcining rotary kilns are lined with __________ bricks.
    (A) Fireclay
    (B) Carbon
    (C) 85% alumina
    (D) Corundum

13. Fireclay bricks are used in the
    (A) Furnaces allowed to cool frequently
    (B) Flues
    (C) Chimney linings
    (D) All (a), (b) and (c)

14. Carbon refractory blocks
    (A) Are wetted by molten iron
    (B) Are used in the hearth of blast furnace
    (C) Are acidic in nature
    (D) All (a), (b) and (c)

15. Spalling of a refractory means its
    (A) Softening
    (B) Fracture due to uneven expansion at high temperature
    (C) Resistance to compressive loads
    (D) Resistance to chemical action of gases and molten fluxes

Show and hide multiple DIV using JavaScript View All Answers

 Next Tests: