Abstract: The application of radiographic testing technology on tube to tube-sheet welds can significantly reduce the leakage of heat exchanger in running rate. The earliest technology uses 192Ir source gamma-ray + film system. As a replacement of 192 Ir source gamma ray machine, rod anode X-ray tube can enhance the photographic sensitivity, and effectively solves the titanium weld detection problem. Digital radiographic testing technology (CR and DR) on tube to tube-sheet welds application has been successful, shows clear advantage and good application prospect. The standards of radiographic testing on tube to tube-sheet welds technology are in formulating, which will build a solid foundation for the promotion of the technology.