HEATING CONTROL MODEL OF BILLET REHEATING FURNACE.

摘要

Level 2 system of the invention has introduced additional twenty-four thermocouples that are installed at various locations on the furnace wall and the roof. The thermocouples are provided to estimate heat flux on the billet surface for each position. A billet tracking means which constitutes a module, simulates the billet movement at a regular time-interval and tracks the billets accordingly. The residence time of the billet is estimated from the tracking means. The surface heat-flux and the residence time are used to calculate the billet core temperature and the thermal gradient. Temperature set-points of each zone are determined on the basis of the differences between the desired heating profile and the calculated billet temperature at each location. An adaptive control means to determine an error weight-age factor, and a proportional-integral methodology have been implemented for a bump-less control.