Roll pass design : the key function in control of shape, dimension and mechanical properties of hot rolled products

The art of roll pass design, known since the late 17th century, has turned into a modern technology based on scientific foundations. The purpose of roll pass design is to ensure the production of correct size and shape of a product with defect free surface and intended mechanical properties, and at the same time ensure maximum output at lowest cost, ease the working conditions of the rolling crew and minimize the roll wear. The increased product demands in later years have made it necessary to add also the mechanical properties into the responsibility of the roll designer. Roll pass design is influenced by numerous visible and unvisible factors in the society and ever since the steel melting processes was established, it is obvious that the concentrations in roll pass design depend on the stage of technological development of the society. Today computer aided roll design and finite element methods are established for design of roll passes. By application of CNC machines for roll turning, computer integrated roll manufacturing is the up-to-date technology. In the future, roll pass design will become even more advanced when certain thermo-mechanical processes are growing in importance. Thus the product properties will grow in importance in the work of the roll designer. To meet the challenge of the future, research in fields concerning rolling power, material flow, roll wear, and stability is necessary as well as development of mill control models and methods for improved control of size and shape. Besides intense cooperation between roll designers and metal physicists, it is necessay to meet the challenge of thermo-mechanical rolling. All that work must be carried out in a spirit to make the world a better place for people to live in.