Method and apparatus for heating coils of strip

An apparatus for annealing stacked coils of metal strip having axial openings therethrough comprising:

• a furnace having,
• a roof,
• sidewalls,
• a generally horizontally disposed base for supporting a first coil of metal strip with its axial opening disposed in the vertical position,
• heating means located within said furnace above the plane of the first coil, and
• heating means adjacent the base;
• a first convector coil support between the base and the lowermost coil of strip comprising a generally circular metal plate disposed parallel to the base and having,
• a central opening therein,
• a plurality of spaced grooves in the bottom surface of said plate extending radially outwardly from the central opening to the periphery of the metal plate, and
• a plurality of holes extending through the plate from the grooves to the top surface of said plate;
• and
• a second convector coil support between adjacent stacked coils of metal strip comprising a pair of generally circular metal plates, each plate having,
• one generally planar surface,
• a central opening therein,
• a plurality of spaced grooves in the surface opposite the planar surface, said grooves extending radially outwardly from the central opening to the periphery of the metal plate, and
• a plurality of holes extending through the plate from the grooves to the planar surface, with the plates comprising the second convector coil support disposed between adjacent stacked coils such that the adjacent coils are in contact with a generally planar surface of the coil support, and the central opening and grooves of said plates are disposed toward one another and in axial alignment,
• a cover enclosing the stack of coils, and
• means for supplying annealing gas to the center of the stacked coils inside the cover.