Bell furnace, especially for bright annealing steel strip coils

摘要

A bell furnace, especially for annealing steel strip coils under protective gas, has a protective cover (1) surrounded by a concentric outer cooling cover (2) which has a lid (5) and a wall with air nozzles (7) for directing cooling air jets onto the protective cover, a fan (6) being provided for producing a cooling air flow in the interspace (3) between the covers (1, 2). The air nozzle spacing (a) increases in the upward direction and is 4-20 times the nozzle diameter (d). The cooling cover lid (5) is also provided with air nozzles (7) of spacing (a) 4-8 times the nozzle diameter (d).