VAI's new efficient solution for controlling the mechanical properties of hot rolled strip

The system of VOEST-ALPINE Industrieanlagenbau GmbH (VAI) for Computer Aided Quality Prediction and Control (CAQP/C) allows the accurate online prediction of the quality parameters of hot rolled steel strip. It was developed in close cooperation with one of Europe's best steel producers VOEST-ALPINE STAHL LINZ (VASL) and is in the implementation stage at the hot strip mill (HSM) of VASL. The system calculates the quality parameters for strip segments by means of physical and metallurgical models of the hot rolling process. The input parameters for the CAQP/C are the actual production conditions, which are continuously tracked and recorded. The system covers the HSM process steps from the reheating furnaces to the coiling with an interface to the steel making. The predicted quality parameters comprehend the most relevant mechanical properties such as yield stress, tensile strength etc.. So far the focus is on low carbon and microalloyed steel grades. The motivation for this future oriented technological development was reduction of sampling costs, quality prediction for the entire strip length, thickness and width and the optimization of the production conditions. The extension of the system for the fully automatic online control and correction of the quality parameters is the target of the next step, which is already scheduled.