Document: NUREG-0800
Document ID: c9c204f0-a162-491c-8c25-ee0418212f29
Document Type: srp
Title: PRESSURE-TEMPERATURE LIMITS, UPPER-SHELF ENERGY, AND PRESSURIZED
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0703/ML070380185.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.3.2
CFR Part: 
CFR Title: 

Content:
m an equation of the general form: KI applied = SF * Mm * (p * Ri / t) + KI thermal where: SF = A structural factor applied to the pressure loading as specified in Appendix G to Section XI of the ASME Code and dependent on which P-T curve is being evaluated. Mm = An influence coefficient to convert applied stress to crack tip stress intensity. Mm depends on the orientation of the flaw being evaluated (axial flaws for plates, forgings, and axial welds; circumferential flaws for circumferential welds) and the thickness of the material. Appendix G to Section XI of the ASME Code specifies values for Mm. p = The pressure at the specified condition. Ri = The vessel inside radius. t = The vessel wall thickness. 5.3.2-11 Revision 2 - March 2007 KI thermal = The stress intensity at the crack tip due to thermal loadings (which are only considered for heatup, cooldown, and core critical operation curves). KI thermal may be conservatively calculated from equations given in Appendix G to Section XI of the ASME Code, which depend on heatup/cooldown rate and the vessel thickness. KI thermal may also be more accurately obtained from ORNL/NRC/LTR-03/03 for a given heatup/cooldown rate and the vessel thickness. v. KIc is determined from Figure 1 (taken from Appendix G to Section XI of the ASME Code). KIc is a function of a material’s RTNDT value and temperature at the location of interest (i.e., either the 1/4 T or 3/4 T location). It should be noted that a material’s RTNDT value will vary through the wall thickness as the neutron fluence decreases from the vessel inside diameter to the vessel outside diameter. The reviewer should apply the methods of Regulatory Guide 1.99 for determining the appropriate RTNDT values. It should also be noted that the temperature to be applied in using Figure 1 is the metal temperature at the tip of the postulated flaw from Appendix G to Section XI of the ASME Code (i.e., at either the 1/4 T or 3/4 T location). The metal temperature at throughwall