2008 Volume 48 Issue 6 Pages 799-808
A new mathematical model of a web transport system (WTS) in a continuous annealing process (CAP) is proposed. In general, temperature and gravity effects influence the web of a vertical WTS in a CAP. However, these effects are not systematically considered in the conventional mathematical model of a WTS. Disregard for these effects causes a low quality of webs in the CAP. Therefore, in order to improve the quality of webs, a precise web tension control is required based on a mathematical model with thermal and gravity effects. Thus, the mathematical model with thermal and gravity effects in the CAP was established in this paper. In addition, the feed-forward velocity compensator for the web tension control system was suggested, which was based on the proposed mathematical model with thermal and gravity effects. In order to evaluate the validity of the proposed mathematical model for a vertical WTS and the proposed web tension control system in a CAP, computer simulations that considered thermal and gravity effects were executed and an experiment was implemented.