Convective heat transfer furnace and method

Claim 1

A METHOD FOR HEAT TREATING COLD WORKED METAL STRIP WORK TO EFFECT GRAIN RECYSTALLIZATION AND CONSEQUENT ANNEALING, WHICH METHOD COMPRISES PASSING THE WORK IN A SUBSTANTIALLY VERTICAL DIRECTION THROUGH AN ENCLOSED HEATING ZONE AND THEN THROUGH A SEPARATE AND ENCLOSED COOLING ZONE, CAUSING A HEATED COMPRESSIVEL FLUID TO FLOW WITHIN THE HEATING ZONE IN HEAT TRANSFER RELATIONSHIP WITH THE WORK TO EFFECT HEATING THEREOF, IN A HEATING REGION, FROM BELOW A MINIMUM TEMPERATURE AT WHICH THE WORK IS SUBJECTED TO MARKING DUE TO ROLL PICK-UP AND TO A TEMPERATURE SUFFICIENTLY HIGH TO CAUSE GRAIN RECRYSTALLIZATION AND CONSEQUENT ANNEALING, AND COOLING THE WORK, IN A COOLING REGION OF THE COOLING ZONE, TO BELOW THE MINIMUM TEMPERATURE AT WHICH THE WORK IS SUBJECT TO MARKING BY ROLL PICK-UP, BY CAUSING A COOL COMPRESSIBLE FLUID TO FLOW AT HIGH VELOCITY WITHIN THE COOLING ZONE IN HEAT TRANSFER RELATIONSHIP WITH THE WORK AND BY MAINTAINING A BODY OF LIQUID WATER IN CONTACT WITH THE WORK ADJACENT THE STRIP DISCHARGE END OF THE COOLING REGION, AND WHEREIN THE WORK IS UNSUPPORTED DURING ITS TRAVEL FROM ENTERING THE HEATING REGION TO LEAVING THE COOLING REGION, BUT IS MAINTAINED UNDER TENSION BY FORCES APPLIED EXTERIORLY OF SAID REGIONS.