A method for treating a metal strip, where the metal strip undergoes heat treatment in a directly fired furnace and is subsequently heat-treated further in a radiant tube furnace. At least part of the exhaust gases from the radiant tubes is fed to the directly fired furnace.

Tubular radiant element for industrial plants and the like, made of a metal material resistant to high temperatures, including at least one vertical tubular portion, optionally at least a curved tubular portion, provided with a surface (S), including at least one radiation and stiffening means arranged on at least a portion of the surface (S) of the tubular radiant element.

Support device for a radiant pipe (TR), usable in thermal treatment furnaces, for lines for continuous galvanising and annealing of metal strips or sheets and/or other products made of steel and/or other metals or for revamping pre-existing furnaces, including a support for radiant pipe or shank and a furnace-side support or socket, wherein the support for the radiant pipe or shank includes at least one outer surface, facingduring usetowards the furnace-side support or socket and a thickness, wherein the furnace-side support or socket includes at least one first surface and one second surface, the latter facingduring usetowards the support for radiant pipe or shank, and a thickness, including at least one rotary means and at least one seat for housing the at least one rotary means.

A radiant tubes support device, which can be used in furnaces for the thermal treatment, for continuous lines for galvanising and annealing strips or panels made of metal sheet or other products made of steel or other metals, including a furnace side wall support, constrained to a wall of the furnace, a radiant tube support provided with a tubular element and anti-sticking means between the tubular element and the furnace side wall support for supporting the radiant tube and allowing the lateral oscillation thereof, avoiding the sticking on the furnace side wall support.

A continuous heating furnace includes a furnace main body, a conveyance unit configured to convey a baking object W in the furnace main body, a plurality of heating sections heated by combustion, each having a first radiation surface configured to be heated by combustion and transfers heat to the baking object conveyed by the conveyance unit and arranged in the conveyance direction of the baking object in the furnace main body, and a cooling preheater having a second radiation surface configured to receive radiant heat from the baking object when being opposite to the baking object conveyed by the conveyance unit and a gas flow path configured to preheat a gas used for combustion in the heating section by the heat from the second radiation surface.

Apparatus and methods are described for novel radiant tube coil support designs that are insertable through holes in the casing walls of fired heaters from the outside of the heater.

A continuous heating furnace (200) includes a conveyance body (210) stretched in an endless shape and configured to convey a burning target, a furnace main body (212) partially or entirely surrounding the conveyance body to form a burning space, and a roller (214) configured to support a portion of the conveyance body in the furnace main body. The continuous heating furnace (200) further includes one or more closed gas heaters having an introduction hole configured to introduce a fuel gas into a heater main body, a combustion chamber in which the fuel gas is combusted, a discharge section to which an exhaust gas is guided, a radiation surface heated by the exhaust gas flowing through the discharge section or combustion in the combustion chamber and configured to transfer radiant heat to a burning target, and an exhaust hole configured to exhaust the exhaust gas that heats the radiation surface to the outside of the heater main body, and disposed in the furnace main body, and an exhaust pipe (216) in communication with the exhaust hole of the closed gas heater and through which the exhaust gas is guided. In addition, the exhaust pipe enables heat exchange between the exhaust gas flowing through the exhaust pipe and the roller.

A continuous heating furnace includes one or a plurality of closed type gas heaters each having a combustion chamber, a guide section that guides an exhaust gas, an exhaust hole that discharges the exhaust gas and a first radiation surface that extends in a direction perpendicular to a baking object conveyance direction wherein the first radiation surface is heated by combustion in the combustion chamber and heat from the guide section and transfers radiant heat to the baking object. The continuous heating furnace also has at least one exhaust heat transfer unit that is juxtaposed with a corresponding closed type gas heater in the conveyance direction, wherein the at least one exhaust heat transfer unit has a second radiation surface that communicates with the exhaust hole of a closed type gas heater and is heated by the exhaust gas, and a heat transfer acceleration unit that accelerates heat transfer from the exhaust gas to the second radiation surface in a direction perpendicular to the conveyance direction of the second radiation surface.

Equipment and a method for preheating a continuously moving steel strip, in particular before feeding the same into a continuous annealing or hot-dip galvanizing furnace, involves the continuous movement of the steel strip in a preheating chamber including a preheating circuit having at least one preheating tube, the inner surface of which is in contact with externally-recovered burnt gases (e.g. from the furnace). A portion of the outer surface of the preheating tube is disposed directly opposite a surface of the strip in order to provide a first preheating mode by irradiating heat onto the strip and the walls of the chamber, and a second preheating mode, mainly by convection, of a gas constituting a controlled atmosphere in the preheating chamber.

A radiant heat tube (5) comprises a tube body having a center section (6) and at least one recirculating section (7, 8) arranged next to the center section, said recirculating section forming a loop (9, 10) with said center section. A pivot joint bearing (23) is arranged on one end (12) of the radiant heat tube, while a sliding bearing (15) is arranged on the other end (11) of the radiant heat tube, said sliding bearing (15) being arranged opposite said pivot joint bearing (23). A burner (14) is disposed to heat the radiant heat tube (5).