Chemical Engineering - Refractory Technology
Exercise :: Refractory Technology - Section 3
| 6. |
In panel test for spalling resistance, the average face temperature of panel assembly is maintained at __________ °C for 24 hours. |
Answer: Option C
Explanation:
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| 7. |
Which is not an acidic refractory ? |
| A. |
Silica | | B. |
Fireclay | | C. |
High alumina refractory | | D. |
Carbon black |
Answer: Option D
Explanation:
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| 8. |
Natural silica |
| A. |
mainly contains quartz. | | B. |
is not stable at high temperature. | | C. |
transforms to other allotropic forms i.e tridymite and cristoballite involving very high volume changes. | | D. |
all (a), (b) and (c). |
Answer: Option D
Explanation:
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| 9. |
Thermal conductivity of refractory bricks |
| A. |
increases with decrease in porosity. | | B. |
decreases with decreases in porosity. | | C. |
is independent of its porosity and is maximum for insulating bricks. | | D. |
increases with the amount of air entrapped in pores. |
Answer: Option A
Explanation:
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| 10. |
Dolomite bricks have good resistance to attack by |
| A. |
molten steel | | B. |
iron oxide | | C. |
lime slag | | D. |
none of these |
Answer: Option A
Explanation:
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