Abstract: The core depth of a heat exchanger having parallel, tube-like headers (10, 12; 62, 64) may be reduced through the use of a plurality of second heat exchange fluid conduits (26, 126) located in side by side relation and each having a first port (30, 60, 178) in fluid communication with one of the headers (12, 62) and a second port (32, 168, 174) in fluid commuication with the other of the headers (10, 64) and each defining a serpentine fluid flow path between the ports (30, 32, 166, 168, 174, 178) having a plurality of passes (36, 38, 40, 42, 44; 140, 142, 144, 146; 184, 186, 188) in side by side relation together with fins 28 embracing and bonded to the conduits (26, 126).

Abstract: An improved turbulator and conduit structure for use in heat exchangers. An elongated tube through which fluid to be subject to a heat exchange process is provided with a first outer winding within the tube in substantial abutment with the inner wall of the tube and a second inner winding at least partially within the first winding. The pitch of the first winding is different from the pitch of the second winding. Consistent heat exchange at extremely low Reynolds numberes is obtainable with the structure. Also disclosed is a method of making such a turbulator and conduit structure.

Abstract: A connection for securing a tank to a header plate in a heat exchanger. A metal header plate is provided with a peripheral groove having a bottom wall and an upstanding side wall. A compressible gasket is received in the groove in a plastic tank as a flange disposed in the groove to compress the gasket. A plurality of tabs are deformed from the side wall to overlie a side of the flange. The tabs are generally egg-shaped or spherical and have free edges engaging the flange to provide excellent resistance to deformation.

Abstract: A cooling radiator having a secondary cooling means and comprising a pair of spaced liquid coolant tanks, one of which is an inlet tank having a liquid coolant inlet adjacent one end and the other of which is a liquid outlet tank having an outlet adjacent its corresponding opposite end, interconnecting spaced coolant tubes between the tanks, a heat exchanger for cooling a second liquid such as engine oil located in the outlet tank with the heat exchanger having a spaced inlet and outlet and a confined liquid space therebetween for flow of this second liquid through this spaced and an internal fin within the heat exchanger located within an inner tube of the heat exchanger in heat exchange relationship with the liquid coolant in the outlet tank.