Abstract: A modular heat exchanger comprises modules connected in parallel. Each module represents by itself a casing inside of which there is provided a bundle of straight pipes for the first coolant; the open ends of the straight pipes adjoin tube plates. The latter are secured on the casing which has an inlet and outlet for the second coolant coming into contact with the intertube space. The modules are arranged in a shell for a first coolant, to pass therethrough which is fed into the straight pipes and the space between said modules. The shell is provided with an inlet and outlet for the second coolant. Displacers are arranged in the space between the modules, over the entire length of the latter, which displacers ensure equality of the heat-exchange coefficient inside the straight pipes and between the modules.

Abstract: A heat exchanger comprising a number of interchangeable, possibly standardized sections. Each section is made in the form of a bundle of at least partly longitudinally finned tubes, and has strips which serve as spacer elements for fixing the tubes at a certain distance from one another, and bands embracing the tube bundles. The strips have alternating one-sided projections, each projection having the shape of half the perimeter of a rectilineal polygon. Each pair of strips forms cells. The tubes have non-finned portions along the widths of the strips these portions being located at the same level for all the tubes in a section. The cells embrace the non-finned portions of the tubes so that the latter are arranged in parallel rows.