Heat transfer pipe and heating boiler having the heat transfer pipe

摘要

A heat exchanger tube of a heating boiler, comprising an outer tube, which may be flown through by exhaust gases from the boiler firing and which may be surrounded by boiler water on the outside, and a profiled insert inserted into the outer tube, which comprises ribs running in longitudinal direction of the outer tube to enlarge the inner surface of the outer tube and which is in thermally conductive contact with the outer tube, are to achieve that an even greater heat transfer capacity from the combustion gases to the boiler water in the heating boiler is enabled. A first longitudinal section of the outer tube is formed in a cylindrical, smooth-walled manner and a second longitudinal section of the outer tube has at least one cross-sectional narrowing element narrowing the flow cross section. The profiled insert extends exclusively over the first longitudinal section of the outer tube.