Study on Design Improvements of Recirculation SG Based on Ageing Degradations

Design improvements of recirculation SG is discussed based on different ageing degradation mechanisms around the heat transfer tube. The results indicate that the design improvement measurements, such as taking I-690 TT as the heat transfer tube materials, installing the blow down components, supporting the plate with broached quatrefoil or broached trefoil structures, installing V type anti vibration bar at U bend, and conducting all volatile treatment for feed water, can effectively avoid or mitigate the general ageing degradations for the recirculation SG.