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     Under normal circumstances, when decarburization occurs on the surface of cold-drawn tubes, it is because the steel wire comes into contact with the air when molten lead, causing decarburization and oxidation to occur at the same time. This is mainly because the solid solution carbon in the iron comes into contact with gases such as water vapor, oxygen, and carbon dioxide in the air, resulting in severe decarburization on the surface of cold-drawn tubes. There are two ways to solve the problem of decarburization on the surface of cold-drawn tubes.
    1. The air and atmosphere in the furnace can be controlled more purposefully to keep it in a restorative state, which can effectively prevent decarburization on the surface of cold drawn tubes.
    2. Directly spray or blow an appropriate amount of neutral protective nitrogen into the furnace. Nitrogen can dispel the oxidizing atmosphere in certain sections while preventing air from penetrating deep, reducing or avoiding decarbonization problems.
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