Explosive plugging heat exchangers on site. Chapter 7

The requirements which must be satisfied for a plugging repair on heat exchangers are specified. The experiences of the International Research and Development Co. of plugging feed water heaters at various sites and plugging the PFR heat exchangers at Dounreay are described. The plugs used for the evaporator and for the superheater and the procedures for plugging, on site, are described. The sequence of tests for ensuring service suitability is explained. It is concluded that explosive plugging is a successfull repair technique which can be performed with a high degree of quality control. The application to PFR superheaters demonstrates its advantage under poor access conditions. (U.K.)