Simulation of a hot strip steel mill-a high performance case study

The Lackenby Coil Plate Mill is a large-scale steel plant on Teeside. Control of the rolling process is complicated by the interactions along the stands and the effects of the stresses set up on the material between the stands. Control of width and gauge (thickness) is controlled by a series of feedback and feedforward control loops between more that one stand and special devices called loopers, which aid in assessing the interstand tension. If the tension is too great between stands, the material is stretched. Under these circumstances it is necessary to reduce the relative angular velocity error between adjacent stands and also adjust the width of the roll gap (roller force). As material passes down the rolling process, it is important that any disturbances, seen as a result of imperfections in the material, hardness differences and temperature variations (skid-chills), are rejected by the control system. The paper was based upon a short consultancy. The aim was to demonstrate that, using parallel processing it is possible to speed up the simulation of such a plant markedly. The requirement was to use a subset of the complete plant: a stand/looper/stand segment.