E Oznergiz, C Ozsoy I Delice, and A Kural Jed Goodell September 9th,2009 A fast, reliable, and accurate mathematical model is needed to predict the rolling force, torque and exit temperature in the rolling process. Function of Paper: To propose an adaptable neural network model for a rolling mill Why important? An Artificial Neural Network is a computer model designed to simulate the behavior of biological neural networks, as in pattern recognition, language processing, and problem solving, with the goal of self-directed information processing. 1 Sims, R. B. The calculation of roll force and torque in hot rolling mills. Proc. Instn Mech. Engrs, 1954, 168(6), 191–200. 2 Orowan, E. The calculation of roll pressure in hot and cold flat rolling. Proc. Instn. Mech. Engrs, 1943, 150(4), 140–167. 3 Hitchcock, J. H. Elastic deformation of roll during cold rolling. 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R., Berenguel, M., and Camacho, E. F. Neural identification applied to predictive control of a solar plant. Control Engng Pract., 1998, 6, 333–344. 28 Gomm, J. B., Evans, J. T., and Williams, D. Development and performance of a neural-network predictive controller. Control Engng Pract., 1997, 5(1), 49–59. The paper shows an effective way to compute the needed rolling force, torque and temperature needed for hot rolling 1. 2. 3. Empirical Model Lookup tables Neural Network Empirical vs NN Outputs: Rolling force Torque Exit Temperature MISO System– Multi Input Single Output Back Propagation Algorithm To find Force and Torque: Inputs: Roll radius, number of revolutions, entry slab temperature, entry and exit thickness. Output: Force and Torque To find Exit Temperature Inputs: Energy required, exit thickness, radius, number of revolutions, entry slab temperature, slab width, slab volume. Output: Exit Temperature Hot rolling mill at Eregli Iron and Steel Factory in Turkey. The equipment: Slab furnace Pre-rolling mill Reversible mill Seven strip rolling stands Cooling system Shearing System Data Acquisition and Computer control system Dimensions monitored during each pass by an X-ray Temperature monitored with pyrometer Roll force and torque monitored using four load cells placed along the mill NN model was 22 % better predictor for force, 24% better for torque, and 14 % better for exit temperature Errors decreased by 85% for force, 97% for torque, and 92% for temperature Practical use – faster rolling, reduction in energy , more flatness control Simple learning method vs Adaptable NN Offline vs Online – weight update Industries most impacted – any industry using sheet metal