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What is the culprit behind the low hardness of high-precision cold-drawn tubes?
       High-precision cold-drawn pipe is a high-precision steel pipe with outstanding performance in terms of shape, size and function. However, when testing the precision cold-drawn tube, it is found that its hardness does not meet the standard requirements and is on the low side. What is the reason for this?

       During the production process of precision cold-drawn tubes, high-temperature salt bath furnaces are generally used for quenching and heating to achieve the deoxidation effect. However, in actual implementation, complete deoxidation cannot be achieved. When it interacts with the carbon on the surface of the precision cold-drawn tubes, insufficient hardness will occur.
       In addition, the cooling rate during the quenching process should also have a relatively large impact on the hardness of fine cold drawn tubes. Generally, the slower the cooling rate, the more the hardness of the product will decrease. In order to avoid the occurrence of this phenomenon, salt bath deoxidation must be strictly carried out, and the cooling temperature and time must be strictly controlled to achieve satisfactory products.