Stress and fatigue and ratchet analysis of the main spray line of the pressurizer

The spray line of the nuclear power station play an important role in regulating and controlling tho pressure of the primary system and also in keeping the reactor operating. Consequently, it is necessary to do some mechanical analysis for the spray line in order to ensure its safety. In this paper, stress analysis of the spray line in all kinds of condition and fatigue analysis have been done. Furthermore, the progressive deformation by thermal ratchet has been verified. The results indicate that the stress and the fatigue strength of the spray line are satisfied. And the progressive deformation by thermal ratchet is also satisfied. (authors)