PROCESS AND DEVICE FOR FILLING,WITH A HARDENABLE FILLER,GAPS WHERE CORROSIVE ATTACK CAN OCCUR IN TUBE AND FIN TYPE HEAT EXCHANGERS

摘要

To fill up the ring-shaped gaps between the tubes and fins of a tube and fin type heat exchanger with a corrosion protective hardenable filler, a unit made up of two closing pieces with filler material between them is pushed by means of the tube to be inserted in the stacked fins through the space formed by the collars of the openings in the fins which are stacked together for assembly into a heat exchanger. On passing this unit through the stacked fins the ring-shaped gaps are filled up with the filler material. The remaining thin film on the collars is also forced into the ring-shaped gaps when the tubes are subsequently expanded. A device for carrying out the process comprises a sleeve with a mandrel which slides inside the sleeve and forms a seal with the sleeve and a piston which likewise slides in the sleeve and forms a seal therewith and which lies ahead of the mandrel forming a space which can be varied in size and which accommodates the filler material. This device is positioned at and in line with a cylindrical space formed by the collars of the stack of fin material, and the unit comprising the piston and mandrel with filler material between them is pushed out of the sleeve and through the cylindrical space formed by the stacked batch of fins.