Abstract: The invention relates to a heat exchanger comprising two manifolds (10). Profiled pipe sections (11) are accommodated with a lamella configuration (12) between said manifolds. According to the invention, an obstructing means (13) for preventing the flow of solder is provided on the exterior of the profiled pipe section (11) between the manifold (10) and the lamella configuration (12). The invention also relates to a method for producing a heat exchanger. The invention provides that the obstructing means (13) is formed on the profiled pipe sections (11) before the sections are cut from a profiled pipe billet.

Abstract: In a method for partial or complete coating of surfaces of components of aluminum and its alloys with a uniform layer of homogeneously distributed solder, fluxing agent and binder for brazing of the components to one another, the solder, fluxing agent and binder are applied in powder form at high speeds up to 180 m/min onto the surfaces provided for brazing by electrostatic powder coating. The powder particles have a particle size of 5 to 30 &mgr;m. The proportion of binder relative to the total quantity of powder is smaller than 35% by weight. The uniform layer of homogeneously distributed solder, fluxing agent and binder has only a thickness of less than 50 &mgr;m. Heat is used melting this layer.

Abstract: The present invention deals with the problem of changing the design of the roof rails, which have hitherto been of a multipart design, in such a way that they can be manufactured in a simple manner and at a lower cost. This is achieved according to the present invention by the spar and the feet including one component, which is preferably formed by a deformed hollow chamber section. To achieve this, the hollow chamber section is deformed downward in a gentle arch at its end. The deformed bent section is cut off on the underside obliquely to the curved longitudinal axis of the section. The bottom of the hollow chamber section is then pressed in from below, so that an omega-shaped cross section is formed. The roof rail thus prepared has a consistently elegant shape, which does not reveal how it was made.