Heat exchanger manufacturing method and apparatus

Abstract From the Canadian patent

A heat exchanger and heat exchange tubes therefor are disclosed as well as a method of making same wherein, locating bulges are formed in the distal end portions of the heat exchange tubes to locate and retain the heat exchanger headers in position during assembly. The bulges are formed by supporting the heat exchange tubes along their length, such as with a plurality of stacked heat exchange fins through which the tubes pass and injecting, high pressure fluid into the ends of the tubes. The tubes are inserted into the headers and the bulges engage the headers to maintain the spacing therebetween during assembly.