Effect of dual actuating strip guidance systems in a continuous steel annealing line

Abstract

In the past, Royal Hoogovens, a main primary steel and aluminum manufacturer in the Netherlands, used pre-shaped rolls and sophisticated tension tables to guarantee good strip tracking for all strip geometry's in both their Continuous Annealing lines. However: with an increasing product mix (wider range of geometrical dimensions: widths between 800 - 1200 mm and thickness' between. 0.15 - 0.30 mm) in combination with high annealing temperatures of approximately 1000 K, these methods were not sufficient anymore. The steel strips became too vulnerable for wrinkles. To prevent wrinkles and tracking problems, Hoogovens Packaging Steel improved the flexibility of a processing line by partly substituting the pre-shaped rolls by flat rolls and new steering rolls. Before this process was started, a lot of time was spent, developing a suitable new steering roll type. This steering roll, it is called the DUal Actuating strip guidance System (DUAS), has a minimal influence on the strip tension distribution, basically consists of a flat roll and two hydraulic actuators mounted on a small frame and fits in an existing installations without large modifications. In December '95 the first system was placed in the furnace of one of the Hoogovens annealing lines and in November '96 another two.