PERMUTADOR DE CALOR EM PLACAS

A layered heat exchanger comprises pairs of generally rectangular adjacent plates (2), each of the plates being formed in one side thereof with a U-shaped channel recess (3) and a pair of header recesses (4) continuous respectively with one end and the other end of the channel recess and each having a fluid passing opening (8), the plates (2) being joined together in layers with the corresponding recesses (3) of the plates (2) in each pair opposed to each other to thereby form juxtaposed flat tubes (5) each having a U-shaped fluid channel, and front and rear headers communicating respectively with opposite ends of each flat tube (5) for causing a fluid to flow through all the flat tubes and headers. At least one of the adjacent plates (2) in each pair is provided with a U-shaped divided channel forming ridge (15,16) on a bottom wall of the channel forming recess, the pair of plates (2) being fitted and joined to each other with the corresponding recesses (3) opposed to each other to thereby form a plurality of U-shaped divided independent channels of reduced width inside the flat tube (5).