Industrial furnace cooling system

Claim 1

IN A COOLING SYSTEM FOR AN INDUSTRIAL FURNACE FOR THE ANNEALING OF A STACK OF METAL COILS, HAVING A HEARTH, AN INNER COVER COVERING SAID STACK AND A CENTRIFUGAL FAN AT THE FOOT OF SAID STACK TO CIRCULATE A PROTECTIVE ATMOSPHERE AROUND SAID COILS WITHIN SAID INNER COVER, APPARATUS COMPRISING, IN COMBINATION, AN ANNULAR BASE HAVING A CENTRAL OPENING IN VERTICAL CONCENTRIC ALIGNMENT WITH THE CENTRAL OPENING THROUGH SAID STACK, AN OUTFLOW DUCT FOR AN ATMOSPHERE COOLING CIRCUIT CONNECTED TO THE INTERIOR OF SAID BASE, MEANS FOR COOLING SAID OUTFLOW DUCT, AN INDIRECT RELATIVELY LOW-PRESSURE-DROP HEAT EXCHANGER CONNECTED TO SAID OUTFLOW DUCT, SAID HEAT EXCHANGER HAVING AN EXTENSIVE SURFACE AREA FOR HEAT TRANSFER FROM SAID ATMOSPHERE, A RETURN DUCT CONNECTED TO SAID HEAT EXCHANGER TO RETURN THE PORTION OF THE ATMOSPHERE BEING COOLED TO THE SPACE WITHIN SAID INNER COVER, INDEPENDENT FAN MEANS IN SAID COOLING CIRCUIT FOLLOWING SAID HEAT EXCHANGER TO REGULATE THE FLOW OF ATMOSPHERE THROUGH SAID COOLING CIRCUIT AND WITHIN SAID INNER COVER RESPECTIVELY IN COOPERATION WITH SAID CENTRIFUGAL FAN, VALVE MEANS IN SAID COOLING CIRCUIT FOLLOWING SAID HEAT EXCHANGER TO REGULATE THE FLOW OF ATMOSPHERE THROUGH SAID COOLING CIRCUIT, MEANS FOR CIRCULATING A LIQUID COOLANT IN A COUNTERCURRENT DIRECTION THROUGH SAID HEAT EXCHANGER AND FIRST-NAMED MEANS, AND MEANS FOR REGULATING THE FLOW OF SAID LIQUID COOLANT IN ACCORDANCE WITH THE TEMPERATURE RISE THEREOF IN SAID COOLING CIRCUIT.