Vacuum and Completion Process
In recent years, the need for steel with a very clean structure has emerged. Very clean steel means that the quality and quantity of gases such as H, N, O and S, As and nonmetallic inclusions in the steel do not cause any problems in hot processing of the steel and in the place of use and the VOD (Vacuum Oxygen Decarburisation) method is used for the production of such properties. The application of the VOD process in the converter is known as the VOD-C method. This provides a slightly faster steel production of the same quality. Vacuum degassing is one of the most important stages of special steel production. The dissolved O, H, N gases in the liquid steel are one of the most important impurities that cause errors while producing steel. These gases can cause many negativities from residue formation to crack formation.
Genelde çelik döküm hataları şunlardır:
Commonly, steel casting faults are
• Non-metallic residues
• Gas spaces
• Casting cavities
• Segregations (Accumulations)
• Alloy segregations
• Carbide segregations
With the vacuum process, it is possible to minimize these errors, to produce steel with low carbon content, to produce steel close to chemical composition ranges, to control pouring temperatures in continuous casting processes and to produce high quality steels.
THE COMPLETION AND CRACK CONTROL PROCESSES OF STEEL
Completion process is the whole process of sandblasting, precision straightening, straightness control, dimensional control, clutter control, surface crack control and internal defect control processes. All of the completion steps are carried out in accordance with the relevant international standards.