JPS57143441A - Continuous heat treating furnace for strip material - Google Patents

Abstract

PURPOSE:To suppress the overshooting phenomenon of the temp. of a strip material by providing air-permeable solid walls between the opposite faces of the strip material and the furnace walls to segment the furnace inside to heating chambers and waste gas chambers, and providing blowing devices for heating and cooling gases in the heating chambers. CONSTITUTION:In a continuous heat treating furnace for a strip material 2, air- permeable solid walls 3 are provided between the material 2 and furnace walls 1 to segment the furnace inside to heating chambers 8 and waste gas chambers 9. Blowing devices 5 for heting and cooling gases are provided in the chambers 8. The heating gases supplied from the devices 5 fill the chambers 8 because the walls 3 have presssure drops, and during the passage through the solid walls 3, the heat transfer from the heating gases to the walls 3 is caused by convection heat transfer; further the strip material 2 is heated by the radiation heat transfer from the walls 3. On the other hand, when the line goes out of order, the heating gases from the device 5 are switched to the cooling gases to fill the cooling gases in the chambers 8.