Abstract: A charge air cooler is provided made up of a plurality of spaced generally parallel turbulators, each said turbulator comprising an outer channel member having a bottom wall and two transverse side edges, an inner channel member having a bottom wall and two transverse side edges, the side edges of the inner channel interfitting closely within the side edges of the outer channel member, an accordian shaped fin assembly between said channels having side edges of a plurality of accordian folds in contact with the bottom wall of both the inner and outer channel members, a transverse heat exchanger fin assembly between adjacent turbulators, frame means surrounding said turbulators and heat exchangers, header means at each end of said turbulators, and flange means around the periphery of each said header means forming therewith one of an inlet and outlet well whereby the turbulator ends may be operatively connected to a source of fluid to be cooled.

Abstract: An exhaust gas cooler for internal combustion engines of land based vehicles is provided having an outer elongate housing and a pair of spaced inner housings forming within them exhaust gas passages and with coolant passages between the walls of the inner and outer housings carrying coolant around the inner housings. Said housings are formed of sheet metal and interconnected along their edges with a metallurgical bond.