What are the abnormal phenomena of white aluminum oxide in front of the smelting furnace and how should they be dealt with? Today I will give you a brief introduction.
1. Arc breaking
Features: No current display, no sound in the furnace, no flash between electrodes.
Causes: The arcing rod is not fixed well, the rod is removed too early, and there is less melt; the material is added too fast, the aluminum oxygen is immersed and blocks the current path, the cross-furnace reaction forms a hard block, and the electrode is blocked from falling.
Solution: Check before starting the arc; remove the carbon rod after the furnace condition is stable; pay attention to the feeding speed; move the electrode frequently when stringing the furnace; and restart the arc.
2. Skewers
Features: The molten liquid flows rapidly back and forth in the solid powder material, stirring up a large amount of aluminum oxide powder, sometimes causing arc interruption, which usually occurs within 10 hours after starting the furnace.
Reasons: The material layer at the edge is thicker, the melting surface at the bottom of the furnace is small, and the feeding is uneven, resulting in uneven heating. When the melt comes into contact with the furnace wall in a certain part or the air pressure in the furnace is high, the melt spurts out and a large amount of cold material flows in.
Solution: Use lower voltage in the first few hours, expand the melting surface, and increase the liquid volume; in severe cases, break the hard lumps, level the charge, and deal with it thoroughly.
3. Shoot off
Features: There is a sudden roar in the furnace, and a large amount of hot gas and fire balls are ejected. When there is no furnace lining, the furnace shell will turn red at the place where the blast is fired. In severe cases, it will cause furnace leakage.
Causes: The furnace bottom and furnace lining are damp, the raw materials are damp, external water infiltrates, the material layer is too thick, and improper operation causes excessive air pressure in the furnace.
Solution: Prevent moisture at the bottom of the furnace; control the moisture content of the raw materials; strengthen operations to ensure a uniform material layer; increase the amount of cooling water for unlined furnaces; handle them in a timely manner to break agglomerates and smoothen the charge.
4. "Pull out the furnace lining"
Features: The molten liquid reacts with the furnace lining, and the molten liquid jumps over the material layer. In severe cases, it is difficult to suppress the added material, and even furnace leakage accidents may occur.
Causes: Improper operation, uneven or uncomfortable feeding, too thin material layer outside the electrode, too close electrode to furnace wall, too low voltage, etc.
Solution: Add white aluminum oxide waste to the outside of the electrode, with a particle size of 20-40mm; adjust the voltage or electrode distance; reduce the current, reduce the input power, increase the amount of cooling water; stop the furnace if necessary.
