1. Briefly describe the principle of selecting raw materials for steelmaking?

Mass production at home and abroad proves that implementing the fine material policy is an important way to realize the automation of the converter steelmaking process and improve various technical and economic indicators. The raw materials are mainly composed of: molten iron, scrap steel, slag-forming materials, ferroalloys, and oxygen. Reasonable selection of raw materials according to the smelting steel grade, operating technology and equipment level to achieve low input, high quality output principle.

2. What is the main way to reduce blow damage?

1 Concentrate policy, reduce slag volume

2 Reasonable slagging system

3 Adopt a reasonable oxygen supply system and loading system to reduce mechanical splashing.

4 Using thermal compensation technology, eat more scrap steel and reduce chemical burning loss.

5 Adopt reasonable double blowing technology.

3. What is less slag operation and the advantage of less slag operation?

When the amount of lime added per ton of metal material is less than 20kg/t, the slag formed per ton of metal is less than 30kg/t, which is less slag operation.

1 The amount of lime added is small, the slag and energy consumption are reduced, and the emission of pollutants is reduced.

2 The utilization rate of oxygen is high, the end point oxygen content is low, the residual manganese is high, and the alloy yield is high.

3 Reduce the erosion of the lining and reduce the splash.

4. What are the ways to reduce oxide inclusions in steel?

To reduce oxide inclusions in steel, foreign inclusions should be minimized. Improve the purity of raw materials; adopt reasonable smelting process, deoxidation system and refining process of molten steel according to the requirements of steel grade; improve the quality and performance of refractory materials used in converter and gating system; reduce and prevent secondary oxidation of molten steel, maintain normal Casting temperature, full-scale protective casting, select good performance of protective slag; the selection of reasonable steel hot processing and heat treatment process are beneficial to improve the properties of inclusions and improve steel quality.

5. Why is argon gas blown without nitrogen?

Argon in inert gas, which is not dissolved in molten steel and reacts with any element, is an ideal stirring gas and is therefore widely used. Nitrogen is the same as argon in terms of agitation, and nitrogen is cheap, but at high temperatures, nitrogen can be dissolved in molten steel, and its nitrogen increase increases with temperature and nitrogen blowing time. When the temperature is higher than 1575 °C When the nitrogen content in the steel is increased by 0.003%, which affects the quality of the steel, the use of nitrogen as a stirring gas is limited, and only a small amount of nitrogen-containing steel can be used as a stirring gas, and there is also a nitrogen-instabilizing instability problem.