Abstract: A crossfire tube for attachment between casing bosses of combustors includes a bellows assembly having a bellows with opposite cylindrical ends welded to annular flanges. The annular flanges include a bolt circle for securing the flanges to the combustor bosses. The flanges bear against a gasket for sealing against inserts welded to the casing bosses for retrofit in the sealing assembly to combustors or to seats where the inserts and bosses are formed integrally during original equipment manufacture. A telescoping cylindrical sleeve surrounds the bellows to protect from falling foreign object damage.

Abstract: A double wall venturi chamber having a converging section, a diverging section and a cylindrical section wherein said chamber defines a venturi zone in which compressed air, fuel and combustion products flow downstream through converging section, diverging section and cylindrical section, and has a cooling gas passage between the walls of the venturi chamber, a least one cooling gas inlet in an outlet wall of the venturi chamber, and at least one cooling gas outlet in an inner wall of the venturi chamber, wherein said cooling gas outlet is in at least one of the diverging and the cylindrical section, and the outlet is downstream of the at least one cooling gas inlet and upstream of an axial end of the chamber.