Hot blast stoves

Abstract From the Canadian patent

P-PWU-24/CA, Abstract of the Disclosure ==========================, Intercrystalline stress corrosion of the walls of heat exchangers employed to produce hot air for injection into a blast furnace, particularly the wall of the passage interconnecting the combustion and heat exchange chambers is avoided by eliminating pressure differentials across the walls. Also, the walls of the heat exchanger are heated to a temperature above the condensation point of deleterious vapors present or formed in the apparatus to thereby further minimize the possibility of occurrence of stress corrosion.