Research Of Automation Application In VOD Refining Process For Stainless Steel Making

The refining of stainless steel is a complicated process.Vacuum oxygen decarburization, (VOD), is the main way to refine high quality stainless steel, in which the technology is very complicated, the control parameter is instable, and has many influencing factors.Many methods have been proposed to solve this problem, such as PID control, expert system, learning system and so on.This thesis researched the development history of VOD and the requirement of the technics deeply, and analized requirements of the control platform, including both hardware and software parts. Since the system have the high requirement to the time variability and rapid is sensitive to the influencing factors.The project is proposed, in which functions is complited individually while called uniformly. In the industrial field, the project performs stably.Blowing oxygen control system is the key of the process, which is time-variable, and has high requirement to speed. A fuzzy control is proposed control algorithn of the blowing oxygen system to solve this problem. After researching the technics and selecting data, the expert's experience is concluded and deduced repeatly, and the effectly fuzzy rules were achieved finally. Through Mamdani max and min rules, the fuzzy decision is formed, which satisfied the requirement of real-time and for system.When the system works, the error of the vacuum meet the technological requirement, and the controlling of the oxygen flow up to desigh standard. The system not only works well to practical production, but also provides a good reference for the smelting control of the same type.