All titanium condensers with seal welded tube-to-tube sheet joints. Experience from retubing of Ringhals no 2 and no 3

In Swedish nuclear power stations it was clear after a rather short time of operation that Al-brass tubes were deteriorating rapidly because of corrosion attacks, despite all safety measures. For Ringhals no 2 which was the first unit to get all-titanium condensers with seal welded tube-to-tube sheet joints the procedure was very much facilitated since condenser design and plant lay-out made shop manufacture of complete tube bundles possible, which was considered the only way to ensure the clean environment. When the retubing of Ringhals no 3 was due it was however, based on previous experience, obvious that adequate clean room conditions could be arranged on site without too much effort. The welding has been very successful. Of a total number of some 180000 welds only some hundred have been repaired, most of them probably on doubtful indications