Abstract: A device for mounting burners inside a duct for gas and comprising at least one fuel injection pipe having a nose disposed in the head of said burner on an axis parallel to the axis of the duct. The injection pipe is situated inside a sheath secured to the burner head for feeding it with air from outside the duct and disposed transversely relative to the axis of the duct, and the nose of the injection pipe, situated at the end of a bent portion of the pipe, is movable along the axis relative to a guide orifice secured to the burner head, from which it is suitable for being disengaged by the injection pipe being moved inside the sheath from outside the duct, thereby making it possible, from outside the duct, to extract the injection pipe completely to the outside of the duct.