Patent ID: 9618279
Date: 2017-04-11
CPC Classifications: F28D,F28F

Claim:
1. A metal heat exchanger tube ( 1 ) for the evaporation of liquids on the outside ( 21 ) of the tube, comprising a tube axis, a tube wall ( 2 ), and integrally formed ribs ( 3 ) that run circumferentially on the outside ( 21 ) of the tube and have a rib foot ( 31 ), rib flanks ( 32 ), and a rib tip ( 33 ), wherein the rib foot ( 31 ) projects substantially radially from the tube wall ( 2 ), the ribs ( 3 ) are provided with notches ( 51 ) which extend in a direction towards the rib foot ( 31 ) from the rib tip ( 33 ), there is a respective groove ( 35 ) between every two ribs ( 3 ) that are adjacent to one another in the axial direction, and wherein lateral material projections formed from material of the ribs ( 3 ) are arranged on the rib flanks ( 32 ), characterized in that at least first ( 41 ), second ( 42 ), and third ( 43 ) lateral material projections are arranged in such a way that the grooves ( 35 ) are largely covered by the material projections ( 41 , 42 , 43 ) taken as a whole, the first ( 41 ), second ( 42 ) and third ( 43 ) lateral material projections are formed on levels that are in each case differently spaced apart from the tube wall ( 2 ) in the radial direction and the depth of the notching is less than the height (H) of the ribs ( 3 ), on the level of the notches ( 51 ), material of the rib ( 3 ) forms first lateral material projections ( 41 ), which, on a first level, partially cover the groove ( 35 ) between two ribs ( 3 ) that are adjacent in the axial direction, there are second lateral material projections ( 42 ) between the rib tip ( 33 ) and the level of the notches ( 51 ), said projections partially covering, on a second level, the groove ( 35 ) between two ribs ( 3 ) that are adjacent in the axial direction, and the regions ( 54 ) of the rib tip ( 33 ) which are situated between two notches ( 51 ) that are adjacent in the circumferential direction of the tube are widened in the axial direction, with the result that the widened regions ( 54 ) of the rib tip ( 33 ) form third lateral material projections ( 43 ), which, on a third level, partially cover the groove ( 35 ) between two ribs ( 3 ) that are adjacent in the axial direction, characterized in that the grooves ( 35 ) between two ribs ( 3 ) that are adjacent in the axial direction are largely covered by the material projections ( 41 , 42 , 43 ) taken as a whole.