Abstract: The present invention relates to a boiler having horizontally arranged flat rectangular water tubes comprising: a water chamber; an inner water chamber to be connected with horizontal water tubes, said horizontally arranged water tubes forming multi-step water tube groups; induction plates provided in the inner water chamber blocking the water path of the horizontal water tubes alternatingly in such a manner as to bend the water path in a zigzag manner; an exhaust gas discharge conduit in straight lattice lines formed by narrow gaps between the horizontal water tubes; and an exhaust gas discharge chamber formed in an upper water chamber. The flat horizontally arranged rectangular water tubes are narrow in their width, making it possible to arrange them densely in the limited space of the combustion chamber, and with their increased heat receiving areas, the water tubes can heat the water in the boiler fast.

Abstract: The present invention relates to a boiler having horizontally arranged flat rectangular water tubes comprising: a water chamber; an inner water chamber to be connected with horizontal water tubes, said horizontally arranged water tubes forming multi-step water tube groups; induction plates provided in the inner water chamber blocking the water path of the horizontal water tubes alternatingly in such a manner as to bend the water path in a zigzag manner; an exhaust gas discharge conduit in straight lattice lines formed by narrow gaps between the horizontal water tubes; and an exhaust gas discharge chamber formed in an upper water chamber. The flat horizontally arranged rectangular water tubes are narrow in their width, making it possible to arrange them densely in the limited space of the combustion chamber, and with their increased heat receiving areas, the water tubes can heat the water in the boiler fast.

Abstract: A double pipe is disclosed for mixed boilers comprising rectilinear segments in which the two duct sections are juxtaposed laterally. Each section (A,B) is defined, on its side the furthest away from the other section, by a plate (1,7) whose two longitudinal borders (2,3,8,9) are curved and are welded against the longitudinal borders of an intermediate partition (4) and this intermediate partition has stamped bosses (5) whose tops (6) are in contact with said plates and are fixed thereto.

Abstract: An assembly of a plurality of heat exchange units arranged in stacked formation in separate banks with a plurality of vapor and liquid manifold elements interposed between said banks and connected thereto by suitable conduits. The various layers of each stacked bank includes a plurality of heat exchange units arranged in a common horizontal plane with the manifold elements connected to each unit.