Copper mould tube is an important part of the continuous casting machine. It plays the role of molten steel condensation forming. The copper mould tube’s quality and efficiency directly affect the quality of the billet, the operating efficiency of the continuous casting machine.
In continuous casting production process, the coating on the inner wall of the copper mould tubes in contact with the high-temperature molten steel, which is prone to friction, corrosion, etc. causes thermal deformation of the crystalline copper tube, which leads to damage to the inner surface coating. Therefore, improving quality and life of the copper mould tubes can be guaranteed to improve the working quality and efficiency of the continuous casting machine.
As a professional manufacturer of copper mould tubes, Shengmiao has been working hard to find the way improving coating technical.
In the past, the traditional process of hard chromium coating was used for the inner wall coating. The chromium coating has high hardness and good wear resistance. But the coating is thin; the thermal expansion coefficient of chromium and copper has a relatively large difference, more lateral cracks will appear when used. In the continuous casting process, molten steel will penetrate the copper surface through cracks, causing it to produce more cracks. Therefore, during long-term corrosion of molten steel, the chromium plating layer will appear chalking and falling off, and its wear resistance will be greatly reduced. The chromium plating layer is quickly worn away during the casting process, so the wear resistance of the chromium plating layer is very limited.
In order to improve the wear resistance of the chromium plating layer and prolong the service life of the copper mould tube, a nickel-cobalt alloy plating layer is now added to the chromium plating layer and the surface of the copper tube as a transition layer. The nickel-cobalt alloy coating has good corrosion, heat corrosion and wear resistance. It acts as a bonding agent between the inner surface of the copper mould tube and the chrome-plated layer, which greatly improves the wear resistance of the chrome-plated layer. In addition, after the chromium plating layer is worn out, the nickel-cobalt alloy plating layer can continue the work, which extends the life of the copper mould tube.
If you want to know more about copper mould tubes, please contact us.