Study On Process Monitoring Method And Its Application Of Reheating Furnace

In iron and steel industry, the reheating furnace is one of the important equipments of the steel rolling's product line. As the development of the modern rolling mill, there's more desire of the quality of the reheating furnace's billet. However, there are some inevitable changes as the long running of the product line and the load changing of the produce. So, the quality of the reheating furnace's billet must be affected. A reheating furnace's process monitoring system for the process monitoring of the reheating furnace's produce is designed in this thesis by applying the statistical process monitoring method, with a view to heighten the quality and the efficiency of the reheating furnace and to reduce the cost. This entirely satisfys the industry's demand of the reheating furnace, there is very clear significance.At first, this thesis starts with the appearance, development and actuality of the statistical process monitoring, then introduces the produce process of the reheating furnace and some preparative work for the process monitoring of the reheating furnace. Secondly, some control charts of the single variable statistical control method and two judgement'rules for process monitoring are presented in this thesis. The principal component analysis method (PCA) which deals with the linear relation of the variables and the kernel principal component analysis method (KPCA) which deals with the nonlinear relation of the variables are also described. Two kinds of dynamic multivariate statistical process control method are provided for dealling with the sequence relativity of the sample data:One is expanding the data matrix by using the h anterior observation values, then making PCA or KPCA by using the new data matrix; Another is making a combination by using EWMA chart and PCA or KPCA. In succession, the proposed monitoring methods are tested and compared by using the reheating furnace's data. Thirdly, the designing work of the reheating furnace's process monitoring system is particular described, including the method of data's transfer by OPC communication between the system and WinCC 6.0, and the COM-based method which combines Visual Basic 6.0 with MATLAB7.0. At last, the method of using the reheating furnace's process monitoring system in the produce process of the reheating furnace is described at the end of this thesis.A reheating furnace's process monitoring system is designed by applying the satistical process monitoring method in this thesis, the guide of the reheating furnace's process monitoring system is also described. Using this system, users can understand the state of the system deeply and then adjust the system to a better working condition.