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What problems can occur with white corundum during the smelting process? How should they be dealt with? Without further ado, today the editors from Qianjiaxin Refractories will explain to you what problems arise with white corundum during smelting and how to resolve them. 1. Arc interruption: Characteristics: no current indication, no noise inside the furnace, and no flashes between the electrodes. Causes: The arc rod is not secure, resulting in premature exhaust and less melting; material is added too quickly, causing the alumina to block the current path, and reactions in the series furnace lead to the formation of lumps, which hinders the electrode from falling. Solution: Conduct thorough checks before starting arcing; ensure stable furnace conditions before retrieving the carbon rod; pay attention to the feeding speed; frequently use active electrodes in the series furnace; then restart arcing. II. Series Furnace Characteristics: The molten material flows rapidly through the solid powder material, stirring up a large amount of alumina powder; this can sometimes cause arc interruption, usually occurring within 10 hours after the furnace is started up. Reason: The edge material layer is thick, the melting area at the furnace bottom is small, and the feeding is uneven, resulting in uneven heating. When a part of the melt comes into contact with the furnace wall or when the gas pressure inside the furnace is high, the molten metal is ejected and flows into large amounts of cold material. Solution: In the first few hours, use a lower voltage to expand the melting area and increase the amount of liquid. In severe cases, break up the hard lumps, level out the furnace charge, and carry out thorough treatment. III. Gunfire: Characterized by a sudden roar from within the furnace, along with the emission of large amounts of hot air and flames. In the absence of a furnace lining, the exterior of the gun mechanism turns red; in severe cases, this can lead to leaks in the furnace chamber. Reason: The furnace bottom and lining are moist, the raw materials are damp, the exterior is exposed to water, the material layer is too thick, and improper operation have led to excessive air pressure inside the furnace. Solutions: Prevent moisture at the furnace bottom; control the moisture content of the raw materials; improve operational practices to ensure a uniform material layer; increase cooling water flow in furnaces without linings; address issues promptly by breaking up condensed masses to facilitate smooth feeding. IV. “Removing the Furnace Lining” Characteristics: Reaction between the melt and the lining, with molten metal rolling over the material layer. In severe cases, it is difficult to press for feeding, and even furnace accidents may occur. Causes: improper operation, uneven or inadequate charging, too thin outer layer of the electrodes, furnace walls being too close, low voltage, etc. Solution: Add corundum scrap outside the electrodes, with particle sizes of 20–40 mm; adjust the voltage or electrode distance; reduce the current and lower the input power, as well as increase the amount of cooling water; if necessary, stop the furnace operation. The above is what Xiao Qian has explained in detail to everyone regarding the problems that can arise during the smelting process of white corundum and how to deal with them. Various problems can occur during production, but we need to address them in an orderly manner based on the specific circumstances. Follow Qianjia Xinnai Refractories – the refractories expert right at your side!