Basic open hearth furnace (BOF) is not used for producing ______________ steel?

Related Mcqs:

1. The usual energy consumption in electric arc furnace steel making is _____________ KWh/ton of steel ?

   A. 60 – 100
   B. 400 – 700
   C. 1200 -1500
   D. 2000 – 2300

2. One face of a furnace wall is at 1030°C and the other face is exposed to room temperature (30°C). If the thermal conductivity of furnace wall is 3 W. m-1. k-1 and the wall thickness is 0.3 m, the maximum heat loss (in W/m) is____________________?

   A. 100
   B. 900
   C. 9000
   D. 10000

3. Electrolytic reduction cell used for conversion of calcined Al2O3 to Al is a carbon lined furnace operating at 800-900 °C. The purpose of electric current supplied to the furnace is to___________________?

   A. Achieve very high purity of aluminium (99.9%)
   B. Keep the electrolyte in liquid condition by the generation of heat
   C. Electrolytically dissociate alumina
   D. Both B. & C.

4. The refractory lining of the bottom in a basic electric arc furnace is made of___________________?

   A. Silica
   B. Alumina
   C. Magnesia
   D. Fireclay

5. Coating thickness in case of galvanising of steel sheet generally corresponds to the deposition of _______________ gms of zinc per m2 of steel strip ?

   A. 5-10
   B. 1000-1500
   C. 120-500
   D. 1500-3000

6. Square steel key is normally strong in failure by shear & crushing. Keys are normally made of _______________ steel bars?

   A. Hot rolled mild
   B. Cold rolled mild
   C. Forged
   D. Machinable stainless

7. Steel containing low percentage of nickel, chromium & tungsten are termed as the _____________ steel ?

   A. Wrought
   B. Tool
   C. Alloy
   D. Plain carbon

8. Steel rods are normally used for concrete reinforcement because concrete and steel have almost equal_________________?

   A. Tensile strength
   B. Compressive strength
   C. Young’s modulus
   D. Thermal co-efficient of expansion

9. The ‘transition temperature’ for ductile to brittle behavior of steel increases with increase in the _____________ content in steel?

   A. Carbon
   B. Manganese
   C. Both A nor B
   D. Neither A nor B

10. A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness ______________ metre?

    A. 0.01
    B. 0.1
    C. 0.25
    D. 0.5