Abstract: A heat-exchange element has a plurality of heat-exchange components each having a circular heat-exchange plate. The circular heat-exchange plate has a plurality of ribs projecting from a surface thereof and extending generally in one direction. The outer circumferential edge of the circular heat-exchange plate is divided into four substantially equal edges. The circular heat-exchange plate includes a pair of sealing ribs extending respectively along two diametrically opposite ones of the edges substantially parallel to the ribs, and a pair of end walls extending respectively along two other diametrically opposite ones of the edges substantially transversely to the ribs. The heat-exchange components are stacked into a cylindrical shape in which the end walls of each of the circular heat-exchange plates fittingly engage the sealing ribs of another one of the circular heat-exchange plates.

Abstract: A bank of plates for a heat exchanger, of the type comprising a stack of parallel plates each having smooth-surface edges and an undulated central portion forming, with the associated plates, a dual circuit for countercurrent flow of two independent fluids. The bank is composed of a plurality of superposed elements, each formed by a pair of plates which are joined together. The superposed elements are connected to each other via a continuous or discontinuous longitudinal weld bead.