A METHOD OF HEATING COLD-ROLLED STEEL SHEET AND ANNEALING FURNACE SUITABLE FOR USE IN CARRYING OUT THE METHOD

摘要

1,214,074. Bell type annealing furnaces. ISHIKAWAJIMA-HARIMA JUKOGYO K.K. 19 June, 1968, No. 29254/68. Heading F4B. [Also in Division C6-C7] An annealing furnace for coils of steel sheet comprises a plenum chamber 31 and cover 21 sealed thereto by seals 29. The chamber contains radiant tubes 23 heated internally by gas combustion, above which the coils 30 to be annealed are distributed in a single layer (Fig. 5). Within the cover and above the coils are mounted a further set of radiant tubes 22. Protective gas is circulated over the tubes and coils by fan 27 which extracts the gas from the chamber via duct 40 and discharges it into the cover via duct 41 under control of dampers 24. For cooling the coils after annealing, combustion in the tubes is stopped and a heat exchanger 25 is moved from a position outside the furnace to the position shown in Fig. 2, in the path of the circulating gas.