With increase in the alumina content in firebricks, its fusion point (refractoriness) ?

Related Mcqs:

1. With increase in the alumina content, the refractoriness of high alumina refractories_______________?

   A. Increases B. Decreases C. Remain same D. May increase or decrease...

2. With increasing alumina content, the fusion point of high alumina refractories__________________?

   A. Increases B. Decreases C. Remain constant D. May increase or decrease; depends on its alumina content...

3. Maximum alumina content in high alumina refractory can be as high as _____________ percent?

   A. 30 B. 50 C. 70 D. 90...

4. Pure bauxite is the best raw material for the manufacture of high alumina refractories, in which maximum alumina content can be as high as _____________ percent?

   A. 55 B. 70 C. 80 D. 90...

5. Refractoriness/fusion points of ‘Superduty’ refractories is _______________ °C?

   A. 1520-1630 B. 1630-1670 C. > 1730 D. > 2000...

6. Refractoriness under loads (RUL) is quite close to the fusion temperature (PCE) for _____________ bricks?

   A. Fireclay B. Silica C. Dolomite D. Very low alumina...

7. Because of its very high refractoriness of the order of __________ °C, silicon carbide refractories are used in zinc smelting furnace, muffle furnace and for supporting the wares in tunnel kilns ?

   A. 1800 B. 2200 C. 2400 D. 2700...

8. Presence of MgO in alumino-silicate refractories _______________ its refractoriness?

   A. Increases B. Lowers C. Does not affect D. Either A. or B.; depends on its quantity...

9. Refractoriness under load (RUL) is the most important property for the refractory bricks_________________?

   A. At the hearth bottom of the furnace on which stock is placed B. Used for furnace insulation C. Used in the roof of the furnace D. None of these...

10. . Refractoriness under load (RUL) of fireclay bricks (under a load of 2 kg/cm2) is ______________ °C?

    A. 500 B. 1000 C. >1350 D. >2000...