How to choose the material of gunning material for electric furnace

Source: | Author:ChangXing Refractory | Published time: 1550 days ago | 1116 Views | Share:

The gunning material for EAF include magnesia, magnesia dolomite, magnesia chromite, magnesia carbon, magnesia dolomite carbon, etc. In addition, some highly active seawater magnesia is used in the aggregate to promote sintering and improve the density and strength of gunning layer. In order to make gunning materials solidify rapidly and adhere to furnace lining, a small amount of additives are often added to the aggregate.

① When Al, Mg and other low melting point metal powder are added to gunning, the exothermic oxidation of metal powder helps to increase the temperature, and forms harmless oxide in gunning material, which improves the adhesion between gunning layer and furnace lining.

② Adding spinel Cr2O3, SiC and B4C can improve the oxidation resistance and corrosion resistance of the material.

③ Adding a small amount of 1 ~ 5mm long organic fiber to melt at low temperature to form an air passage, which is conducive to the evaporation and discharge of water in the bond, and prevent cracking.

④ Add 0.1 ~ 2 mm, 10 ~ 40 mm long metal fiber, used in tap hole and other parts, in order to improve the corrosion resistance of gunning layer.

⑤ In order to improve the adhesion and corrosion resistance of gunning material, some slag from metallurgical furnace was added.