Effects of Major Parameters on the P-T Limit Curve Construction of Embrittled Reactor Vessel

Abstract:

To prevent the potential failure of the reactor pressure vessel (RPV), it is requested to operate RPV according to the pressure-temperature (P-T) limit curve during the heat-up and cool-down process. The procedure to make the P-T limit curve was suggested in the ASME Code but it has been known to be too conservative for some cases. In this paper, the conservatism of the ASME Code Sec. XI, App. G was investigated by performing a series of sensitivity analyses. The effects of six parameters such as crack depth, crack orientation, clad thickness, fracture toughness, cooling rate, and neutron fluence were analyzed. The results of P-T limit curves are compared to one another.

• Periodical: Key Engineering Materials (Volumes 261-263)
• Pages: 1647-1652
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.261-263.1647
• Online since: April 2004
• Authors: Sung Gyu Jung, In Gyu Park, Chang Soon Lee, Myung Jo Jhung
• Keywords: Cool-Down, Fracture Toughness, Heat-up, Pressure-Temperature Limit Curve, Sensitivity Study, Stress Intensity Factor (SIF)

References

[2] The cladding effect on the P-T limit curve is insignificant for the reference crack size of 1/4T.

[3] Neutron fluence and cooling rate have some effect on the high and low pressure-temperature region, respectively.