Abstract: Device for heating metal material includes an elongated DFI burner arranged to be driven with gaseous oxidant and gaseous fuel and to be displaceable and longitudinally arranged with respect to the metal material. The burner includes longitudinal tubular vessels for fuel and for oxidant, arranged in parallel to one another and relative to the surface of the metal material. Each of these vessels has an opening through which the fuel and oxidant flow out and then converge in an ignition zone outside the respective vessels, where a flame is generated. Supply devices are arranged via a regulator to keep the pressure constant throughout the respective vessel during operation. Each of the vessels has a longitudinally displaceable piston for controlling the longitudinal extension of the flame in the longitudinal direction of the vessels.

Abstract: Device for heating a metal material, includes an elongated DFI burner device, arranged to be driven with gaseous oxidant and gaseous fuel and to be displaceable and longitudinally arranged with respect to the metal material. The device has supply devices for fuel and oxidant. The burner device includes longitudinal, tubular vessels for fuel and for oxidant, arranged in parallel to one another and relative to the surface of the metal material. Each vessel has one or more openings arranged along the vessel, through which the fuel and oxidant are arranged to flow out and then converge in an ignition zone outside the respective vessels, where a flame is generated. The respective supply devices are arranged via a regulator to keep the pressure constant throughout the vessel in question during operation. Each vessel has a longitudinally displaceable piston for controlling the longitudinal extension of the flame in the longitudinal direction of the vessels.