Heat treatment furnace

摘要

A heat treatment furnace in which a metal strip to be treated W passes through heat exchange chambers 11 before reaching the zone 5 for heating and maintaining temperature. According to the invention the strip returns to the chambers 11 after it has been heated, so that fans can circulate gas against the two parts Wa, Wb of the strip and enable heat to be withdrawn from the hot strip and transmitted to the cold strip. Application to the furnaces for heat treatment of metal strips. <IMAGE>