Method for manufacturing a double-walled heat exchange tube with leak detection,
wherein inner tube is slipped into an outer tube, after a surface profiling has
been provided on at least the outer surface of the inner tube or the inner surface
of the outer tube, and at least the outer surface of the inner tube or the inner
surface of the outer tube has been provided with a layer of soldering material.
After the tubes have been slipped into one another, the inner tube is expanded
such that the outer tube is expanded as well and the surface profiling forms a
leak detection channel between the two tubes, and the soldering material between
inner and outer tube is caused to melt. In a heat exchange tube thus obtained at
the location of the contact between the inner and outer tube, a film-thin, optionally
porous layer from soldering material is present, which layer is bonded, through
melting, to both the inner tube and the outer tube.
