Defining Fuel-Saving Heating Mode for Billets in Through-Type Furnace Using Statistical Model of External Heat Exchange

This article suggests a method to determine a fuel-saving mode for the guaranteed heating of billets in a furnace. The bulk temperature of the billet and its movement rate in the furnace were used as input data. The distribution of fuel loads was calculated using the Nelder-Mead direct search technique. The total amount of fuel consumed to heat the billet was used as the target function. The first-order lag was used as the billet heating model. The mathematical model of the thermal mode was implemented as a multiple regression equation. This model accounts for the impact of the adjacent zones and the billet movement rate in the furnace. The authors analyzed the correlations in the obtained statistical mathematical model, which involved the selection of factors that have the most significant impact on the parameter considered. The coefficients of the mathematical model were calculated using the regression analysis based on the least square method. The developed model was validated for practical usage based on experimental data. The authors calculated the fuel-saving mode for the heating of a single billet. The comparison of the calculated and the existing billet heating modes showed that the transition to a fuel-saving mode can help reduce the total fuel consumption to 2%.

I. Introduction

Continuous furnaces are the key component in technological process of hot-rolling production. Specific fuel consumption is a significant performance indicator for heating devices in rolling shops. Fuel and power consumption make up 30-40% of all rolling production costs, and for hot-rolling plate mills, this figure is over 50% [1]. One of the ways to reduce fuel costs without capital investment and furnace reconstruction is the use of automated control systems (ACS) for the heating process. The deployment of ACS helps reduce fuel consumption by 15% [2].