Real-Time, Model-Based Spray-Cooling Control System for Steel Continuous Casting

Abstract

This article presents a new system to control secondary cooling water sprays in continuous casting of thin steel slabs (CONONLINE). It uses real-time numerical simulation of heat transfer and solidification within the strand as a software sensor in place of unreliable temperature measurements. The one-dimensional finite-difference model, CON1D, is adapted to create the real-time predictor of the slab temperature and solidification state. During operation, the model is updated with data collected by the caster automation systems. A decentralized controller configuration based on a bank of proportional-integral controllers with antiwindup is developed to maintain the shell surface-temperature profile at a desired set point. A new method of set-point generation is proposed to account for measured mold heat flux variations. A userfriendly monitor visualizes the results and accepts set-point changes from the caster operator. Example simulations demonstrate how a significantly better shell surface-temperature control is achieved.

Numerical Analysis of Coupled Turbulent Flow and Macroscopic Solidification in a Round Bloom Continuous Casting Mold with Electromagnetic Stirring

“…In the secondary cooling zone, a convective boundary condition is imposed and the overall heat transfer coefficient is converted according to the cooling water flux density and the radiation heat transfer. [28] In this article, the heat transfer coefficients of the water cooling zone, the air mist cooling zone, and the air cooling zone are, in order, 345, 235, 165 W m À 2 K À 1 . Both the cooling water and the ambient temperatures are 298 K.…”

Hot Ductility Behavior of a Peritectic Steel during Continuous Casting

“…Transverse surface cracks seen on the continuous casting slabs have a great importance in the continuous casting process defects [1][2][3][4][5][6][7][8]. Crack-free slab production is an important key to success.…”

Analysis of the Slab Temperature, Thermal Stresses and Fractures Computed with the Implementation of Local and Average Boundary Conditions in the Secondary Cooling Zones

“…The two dimensional model of slab temperature makes it possible to automatically adjust the water flow rate in the zones of cooling. The formula for HTC calculation developed by Nozaki at al [5] has been also implemented by Petrus at al [6] and Luo at al [7]. In the two dimensional model of continuous casting process Janik at al [8] have also utilized constant in zones HTC.…”