Process for thermal treatment of metal strip reeled into coils

摘要

The invention relates to a process and a device for thermally treating metal strip reeled into coils, especially grain-oriented Si steel strip. In order to carry out the thermal treatment, one or more coils are placed on a movable base and enclosed by a hood which is sealed against the surrounding atmosphere and filled with protective gas. In order to heat and cool the coil(s) according to a predefined temperature curve, the base is moved through different temperature zones of a tunnel furnace. Prior to the base being moved into the tunnel furnace, the annealing chamber sealed by the protective hood is flushed with protective gas. During the movement through the tunnel furnace, the annealing chamber remains connected to a protective-gas source, in order to be able to set the desired composition of the protective-gas atmosphere in accordance with the temperature profile. <IMAGE>