61. The purpose of injection of calcium in to liquid steel is to
62. Permanent lining in L.D. converters is . . . . . . . . bricks
63. Identify the condition that is not beneficial for dephosphorisation of hot metal in an L-Dconverter.
64. In L-D steel making, the final slag can be best described as
65. Which type of condition is required to remove phosphorus during steel making process?
66. Ferritic stainless steels are straight chromium steels containing . . . . . . . . percent chromium.
67. In a basic oxygen furnace, under appropriate conditions, which of the following statements is not correct?
68. Molten steel is kept in a ladle. Due in natural convection. mixing occurs inside the melt. A 1cm diameter sphere is held in the centre of the melt where the steel flows upward. so as to measure the force exerted by the melt on the sphere. The force. F exerted by the melt on the sphere is given by $$F = f\left( {\frac{\pi }{8}} \right).\left( {\frac{{{\mu ^2}}}{8}} \right){\left( {\operatorname{Re} } \right)^2}.$$
Data: Density of liquid steels
= 7100 kg. m-3
Viscosity of liquid steel
= 6.5 × 10-3 kg. m-1. s-1
Reynolds number (Re) of the melt
= 5 × 103
Friction factor (f) = 0.3
The velocity of melt (m.s-1) in the central portion of the ladle would be
Data: Density of liquid steels
= 7100 kg. m-3
Viscosity of liquid steel
= 6.5 × 10-3 kg. m-1. s-1
Reynolds number (Re) of the melt
= 5 × 103
Friction factor (f) = 0.3
The velocity of melt (m.s-1) in the central portion of the ladle would be