Apparatus for heating steel products

An apparatus (10) for heating steel products (100), comprising a furnace of the direct combustion irradiation type, comprising inside it a path for feeding the steel products (100) which extends between an entry end (110) and an exit end (111) of the steel products (100), an entry aperture in correspondence with said entry end (110) to allow the entry of said steel products (100) into said furnace (11) and an exit aperture (150) in correspondence with said exit end (111) to allow the exit of said steel products (110) from said furnace (11), means for feeding a fuel, means for feeding a comburent comprising oxygen, and burners (40, 41) able to operate the combustion of the fuel and of the comburent, wherein said means for feeding comburent and said means for feeding fuel are configured to feed the comburent and the fuel so that oxygen is in a sub-stoichiometric or stoichiometric proportion with respect to the fuel at least in one part of said apparatus (10), wherein said exit aperture (150) is provided with a first sealing device (152) comprising a packing (153) configured to cooperate with a closing door (151) of said exit aperture (150) and first inert gas barrier means (155) configured to prevent the entry of air into said furnace (11), wherein said furnace (11) comprises a lower wall (117) through which hoppers (170) are inserted, each provided with a lower duct (171), at the end of which a plate (173) is connected, wherein each hopper (170) comprises a respective sealing element (174) comprising a packing (175) and a closing element (176) attached to the external surface of said lower duct (171) and covering said packing (175), wherein each of said hoppers (170) also comprises an internal member (177) attached to the external surface of said lower duct (171) inside said closing element (176) and configured to press said packing (175) against said closing element (176).

An apparatus (10) for heating steel products (100), comprising a furnace of the direct combustion irradiation type, comprising inside the furnace a path for feeding the steel products (100) which extends between an entry end (110) and an exit end (111) of the steel products (100), an entry aperture in correspondence with said entry end (110) to allow the entry of said steel products (100) into said furnace (11) and an exit aperture (150) in correspondence with said exit end (111) to allow the exit of said steel products (110) from said furnace (11), means for feeding a fuel, means for feeding a comburent comprising oxygen, and burners (40, 41) able to operate the combustion of the fuel and of the comburent, wherein said means for feeding comburent and said means for feeding fuel are configured to feed the comburent and the fuel so that oxygen is in a sub-stoichiometric or stoichiometric proportion with respect to the fuel at least in one part of said apparatus (10), wherein said exit aperture (150) is provided with a first sealing device (152) comprising a packing (153) configured to cooperate with a closing door (151) of said exit aperture (150) and first inert gas barrier means (155) configured to prevent the entry of air into said furnace (11), wherein the apparatus (10) comprises a furnace divided internally into a first part (20) and a second part (30) disposed in succession along the path for feeding the steel products (100), wherein the temperature (T2) in the second part (30) is higher than the temperature (T1) in the first part (20), wherein the means for feeding comburent and the means for feeding fuel are configured to feed the comburent and the fuel so that oxygen is in a sub-stoichiometric or stoichiometric proportion with respect to the fuel in correspondence with said second part (30), wherein the furnace comprises a post-combustion device able to promote the complete combustion in the first part (20) of the residues of fuel not burnt in the second part (30) of the furnace (10).