Heat exchanger
AssigneeSuddeutsche Kuhlerfabrik Julius Fr. Behr GmbH & Co. KG
InventorsManfred Nonnenmann, Helmut Bardong
Life of this patent
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Abstract
A passage is provided in a heat exchanger water compartment to permit expansion of a tube following its introduction into the bottom of the compartment. The heat exchanger is constructed so that a parameter K.sub.1 is in the range of 1.2 to 8. This parameter is equal to the length of the surface in contact between the tube and the passage multiplied by the ratio of the thickness of the bottom to the thickness of the tube wall, and the ratio of the tensile strength of the bottom material to the tensile strength of the tube material.
Claims8
In a heat exchanger having a thin-bottomed water compartment and a block of thin-walled finned tubes connected to the bottom of the water compartment, wherein the wall thickness of the bottom of the water compartment is less than 3.0mm and the wall thickness of the tubes is less than 1.5 mm, and wherein flange passages are provided in the bottom for the tubes, the improvement wherein the tubes are connected to the passages in the water compartment bottom by expansion alone without additional sealing means and wherein the dimensions and properties of the water compartment bottom and the tubes are selected such that the value of a first parameter K.sub.1 is in the range between 1.2 and 8, where
- K.sub.1 = L.multidot. (S.sub.B /s.sub. R).multidot. (.delta..sub.B /.delta..sub.R),
- L= the length in mm of the surface of the tube in contact with the passage,
- S.sub.b = the wall thickness in mm of the water compartment bottom in the original condition thereof,
- S.sub.r = the wall thickness in mm of the tube prior to expansion,
- .rho..sub.B = the tensile strength of the material of the water compartment bottom in K.sub.p .multidot. mm.sup.-2, and
- .rho..sub.R =the tensile strength of the tube material in K.sub.p .multidot.mm.sup.-2.
Dependencies are inferred from the claim text.