Dry roll furnace arrangement

A method to heat metallic workpieces, said method including the steps of:

• selecting a plurality of workpiece support roller assemblies each of which essentially includes a workpiece engaging roll body secured to a roll bell at each of opposite ends by weld metal;
• providing a filling of ceramic fiber underlying the weld metal joining each roll bell with a roll body;
• arranging said workpiece support roller assemblies at spaced apart intervals along a pass line to extend between elongated side walls having a roof supported thereby to form a furnace chamber, said side walls having aligned cavities dimensioned sufficiently to receive terminal end portions of said roll body to thermally isolate the weld metal from a high temperature environment in said furnace chamber;
• supporting each of said plurality workpiece support roller assemblies for rotation about an axis extending along the length of each of the roller assemblies;
• and
• rotating each of the plurality of workpiece support assemblies to advance a workpiece along the length of the elongated heating chamber.

In a heating furnace for metallic workpieces, a workpiece roller assembly including:

• a workpiece engaging roll body having a body length greater than the distance between the side walls for such a heating furnace to present terminal roll body end portions residing within the aligned cavities in the furnace side walls;
• a roll bell secured to each of opposite ends of said roll body by beads of weld metal, said weld metal beads being juxtaposition by multi-pass tungsten inert welding with the roll body rotating inclined to the horizontal about the central axis thereof, said weld metal securing each roll bell to the roll body being spaced apart by the body length of said roll body to reside within cavities in such side walls by a distance sufficient to thermally isolate the weld metal from the highly heated environment in the furnace chamber;
• and
• a filling of ceramic fiber in each roll bell underlying said weld metal joining for forming a thermal barrier against radiant heating of the weld metal from within said roll body, said ceramic fiber in each roll bell and the thermal isolation of said weld metal from the furnace chamber by the resident sites in the furnace walls preventing embrittlement of the weld metal by thermally induced aging.