High integrity steam generator tube/tube plate joints for the LMFBR

An extensive, two-year development program is now coming to a close. The basic process details necessary to obtain high integrity brazed joints for heat exchanger applications have been defined and are now being verified on a production basis by a leading UK Boilermaker. Replacement tube bundles are currently in manufacture and will be installed in the Prototype Fast Reactor at Dounreay in Scotland during 1981. The use of brazed joints in a sodium-heated steam generator may appear an exacting requirement. However, a comprehensive evaluation program has indicated that they will meet the stress and corrosion conditions anticipated in service. Confidence gained during the testing program has led to a further application at present under development. This is to exploit the technique in the repair of leaking tube-to-tube plate welds in current heat exchangers; the procedures being developed could have application to heat exchanger designs involving closely pitched smaller bore tubes