Heat exchanger for the exhaust gas line of a motor vehicle, method for producing a heat exchanger and assembly tool herefor

A method for assembling a heat exchanger for an exhaust gas system of a motor vehicle comprising the steps of:

• providing a housing having at least one feed-through point formed therein;
• providing an exhaust gas carrying exchanger tube having a first end and a second end;
• inserting the exchanger tube in the feed-through point of the housing, the first end and the second end of the exchanger tube located outside the housing;
• forming a mechanical support structure on an outer surface of the exchanger tube, the mechanical support structure located within the housing;
• forming a mechanical retaining structure on an outer surface of the exchanger tube, the mechanical retaining structure located outside the housing;
• and
• forming a substantially fluid tight seal between the housing and the outer surface of the exchanger tube.