Optimal Scheduling of a Tandem Cold Rolling Mill

Summary We consider the problem of a tandem cold rolling mill to achieve correct output gauge, and satisfactory shape, and surface finish. The essential process variables are roll force, shape and thermal roll crown. The formulation of the equations for these key variables is described. The scheduling problem is formulated as a constrained two point boundary value problem. This is solved using conjugate gradient and projection techniques developed for optimal control problems. Results showing the improvements which can be made in strip shape and general mill operating conditions, by optimising the schedules, are included and discussed.