Steelmaking process (detailed)

The so-called converter steelmaking is to smelt molten iron and scrap steel into steel with the required chemical composition, and make it have certain physical and chemical properties and mechanical properties. At present, converter steelmaking is the most important steelmaking production method in the world

(a) cylindrical; (b) a conical sphere; (c) truncated cone

The main shapes of converters are cylindrical sphere, cone sphere and truncated cone.

Converter steelmaking

(1) cylindrical spherical shape: the shape of the molten pool consists of spherical missing bodies and cylinders. Its advantages are simple furnace type, convenient masonry and easy manufacturing of furnace shell. The internal shape of the molten pool is close to the track of the circulating flow of molten metal. When the diameter of the molten pool is large enough, it can ensure the minimum blowing and splashing under a large oxygen supply intensity, and it can also ensure sufficient depth of the molten pool to make the lining life longer. This kind of furnace is often used in large converters.

(2) Cone-ball type: the molten pool consists of a cone and a spherical missing body. Compared with the cylindrical ball converter with the same capacity, this furnace type has a larger molten pool area under the same molten pool depth, which is beneficial to metallurgical reaction. At the same time, with the erosion of furnace lining, the molten pool changes little, which is beneficial to steelmaking operation. This furnace type is used in European countries with relatively high phosphorus content in pig iron. Most of China's 2,080-ton converters adopt cone-ball type, and there are still differences on the applicability of cylindrical ball type and cone-ball type. Some people think that the cone ball type is suitable for large converter (Austria), while others think it is suitable for small converter (Soviet Union). However, most of the existing large-scale converters in the world adopt cylindrical spherical type.

(3) truncated cone: the molten pool is a cone-shaped platform with big top and small bottom. It is characterized by simple structure and easy repair of flat-bottomed molten pool. This furnace type can basically meet the requirements of steelmaking reaction and is suitable for small converters. In China, this kind of converter is mostly used for converters under 30 tons. The capacity of foreign converters is generally large, so this form is rarely used.