SU1592099A1 - Method of protecting steel jet - Google Patents

Description

The invention relates to metallurgy, specifically to the protection of the jet of metal from oxidation during casting,

The invention relates to metallurgy, in particular to the protection of the jet of steel from oxidation during casting.

The purpose of the invention is to improve the quality of flocation-sensitive steel grades.

The method of protecting a metal jet involves supplying a uniform divergent annular flow of neutral gas along the metal jet in the area between the casting ladle and the metal receiver and blowing the outer perimeter of the upper end of the metal receiver at a speed of 10-30 m / s, while the inner surface of the annular gas flow touches the outer the perimeter of the upper end of the metal receiver.

2

The purpose of the invention is to improve the quality of steel, including flocculent steel grades. The method of protecting a steel jet includes supplying a uniformly diverging annular flow of neutral gas along the metal stream in the area between the casting ladle and the metal receiver and blowing the outer perimeter of the upper end of the metal receiver at a speed of 1030 m / s, while the inner surface of the annular gas flow touches the outer perimeter of the upper end of the metal receiver at a speed of 10—

30 m / s, while the inner surface of the annular gas flow touches the outer perimeter of the upper end of the metal reservoir. 1 il.

When the flow rate of the inert gas in the area of the outer perimeter of the upper end of the metal receiver is less than 10 m / s, circulating air flows occur in the inlet part of the metal <receiver - along its outer perimeter, which leads to air leaks into the internal cavity of the metal receiver and the oxygen content in the gas phase increases by 10–12%.

When the flow rate of the inert gas is more than 30 m / s, the argon consumption and its concentration in the casting zone increase without increasing the quality of the metal.

The drawing shows the device

to protect the metal jet.

. ".- „„ 1592099 A1

3 1592099

four

The device contains a pouring ladle 1, an outlet cup 2, a stream of inert gas 3, a metal receiver 4: a metal jet 5 is indicated.

Π р и м: р »From a steel-teeming ladle 1 with a capacity of 350 tons, steel grade 40X is poured from above · into molds 4 with a capacity of 8.35 tons with an internal inlet section of 450x550 mm. The distance between the bottom of the bucket and the inlet end of the mold is 300-400 mm * The diameter of the steel — discharge cup 2 is 40 mm. Argon flow to protect the metal jet 5 is about 60 Nm ³ / h. Stream 3 inert gas is directed 'close to the outer perimeter of the upper end of the mold at a speed of 1030 m / s.

Using the proposed method allows to reduce the marriage of ingots

for surface defects from 0.81 to 0.37% and reduce the content of non-metallic inclusions in steel by 1.82.0 times.

Claims (1)

Claim A method of protecting a steel stream, including the supply of a uniform annular flow of neutral gas along the jet between the casting bucket and the metal receiver, characterized in that, in order to improve the quality of steel, including floc-resistant steel grades, a flow of neutral gas is produced by blowing the outer surface of the metal receiver , while the gas is fed to the surface of the metal reservoir with a flow rate of 10— 30 m / s in the area of its upper end "