Protecting device for electric arc furnace flue gas duct

The utility model discloses a protecting device for an electric arc furnace flue gas duct. The protecting device comprises an electric arc furnace cover, a furnace cover water-cooled duct, a movable water-cooled duct, a fixed duct, a combustion setting chamber and the like. High-temperature-resistant and wear-resistant castable is poured on the inner sides of the electric arc furnace cover water-cooled duct, the movable water-cooled duct and the portion, entering the combustion setting chamber, of the fixed duct. By means of the protecting device, the service life of the furnace cover water-cooled duct, the service life of the movable water-cooled duct and the service life of the portion, entering the combustion setting chamber, of the fixed duct can be greatly prolonged by 1.5 years or more from the existing average three months.