New Method for Evaluation on Creep Residual Life of Steam Conduits for Boiler

By means of macroscopic inspection, ultrasonic testing, magnetic particle testing, metallographic examination, hardness measurement, thickness measurement of internal oxide layer and metallic layer etc., the creep residual life of steam conduits for boiler in one power plant had been evaluated. The results of evaluation showed that the microstructures of the selectively inspected elbows of six steam conduits had been transformed to spheroidization entirely, but the hardness was normal, and there was not obvious performance degradation. Under current operating condition, the steam conduits can safely serve more than one overhaul periods.