Explosive plugging of heat exchangers

The mechanism and development of explosive welding and particularly the application to tube-to-tubeplate welding is briefly reviewed. The need for plugging of heat exchangers in the power generating industry and the requirement for producing a high integrity weld are discussed. Details are given of the explosive plugging system developed for the reheater heat exchanger of the prototype fast reactor (PFR), including data on weld lengths and distortion of adjoining holes. Results of destructive and nondestructive tests on trial plugging of a seven hole array are given. The system described has been successfully applied to an actual heat exchanger and the procedure followed is briefly discussed