Analysis of the Causes of Damage to Arc Furnace Lining

During the smelting process, the arc furnace body is in a high-temperature state, and the furnace lining is constantly subjected to chemical and mechanical erosion at high temperatures. After each furnace of steelmaking, the refractory lining of the arc furnace is damaged to varying degrees. Donc, the furnace must be repaired in time after each furnace is taken out, which is an important measure to ensure normal smelting and extend the life of the furnace.

Furnace lining structure

The furnace lining includes the furnace wall, furnace bottom, and furnace roof. Parmi eux, the furnace wall has the lowest service life and the worst working conditions. Not only is it close to the arc and has a high temperature, but it is also susceptible to severe erosion by slag.

Furnace lining environment

The furnace lining is generally composed of alkaline materials. The alkaline oxides in the slag (such as CaO, MgO, MnO) have little effect on the corrosion of the furnace lining, while the acidic oxides in the slag (such as SiO2, TiO2, ZrO2, P2O5, etc.) have a corrosive effect on the furnace lining. The effect is very good. The furnace age is mainly directly related to the w(SiO2) in the slag. The basicity of the alkaline arc furnace slag is generally between 24, which makes the slag less corrosive and has a higher impurity removal ability.

Analysis of the causes of damage to arc furnace lining

1. High-temperature erosion
   The internal temperature of the arc furnace is extremely high during operation, usually up to 1600℃ – 2000℃. Long-term exposure to such a high-temperature environment will cause problems such as thermal decomposition, melting or burning of the lining material.
2. Chemical erosion
   The molten metal, scories, oxides and gases in the furnace will react chemically with the lining, causing corrosion or dissolution of the material.
3. Mechanical impact and wear
   The lining of the arc furnace is subjected to mechanical impact and wear for a long time, resulting in partial damage or even shedding of the material.