Document: NRC Regulatory Guide
Document ID: 2704425a-c58a-45c4-93ab-8761721c3e7a
Document Type: regulatory_guide
Title: Evaluation of Reactor Pressure Vessels with Charpy Upper-Shelf Energy Less Than 50 Ft-Lb
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740038.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.161
CFR Part: 
CFR Title: 

Content:
fabricating reactor pressure vessels in the United States. Statistical analyses of these generic data have been performed and reported in NUREG/CR-5729, -Multivariable Modeling of Pressure Vessel and Piping J-R Data' (Ref. 10). These analyses provide a method for determnining the material's J integral fractre resistance that the NRC staff finds acceptable for use in the methods described in this guide. Other methods for determining the material property may be used on an individual-case basis ifjustified. NOMENCLATURE The following terms are used in this regulatory guide and its equations a The flaw depth, which includes ductile flaw growth (in inches). a, The effective flaw depth, which includes ductile flaw growth and a plastic-zone correction (in inches). a*. The effective stable flaw depth, which includes ductile flaw growth and a plastic-zone correction (in inches). a,*. The effective stable flaw depth at tensile instabil ity of the remaining ligament, which includes ductile flaw growth and a plastic-zone correction (in inches). a. The postulated initial flaw depth (in inches). 2c The total flaw length, which includes ductile flaw growth (in inches). B, Net-section thickness of the ASTM E 1152-87 (Ref. 9) test specimen used in determining mate rial tearing resistance, J-R curve, behavior (in inches). Cl ,C2 Coefficients used in the equation for the C3, C4 material tearing resistance, J-R curve. CR The cooldown rate ('F/hour). CVN Charpy v-notch upper-shelf energy (fl-lb.). E Young's modulus of elasticity (ksi). E' /(_v2)O (ksi). F,. F2, F3 Geometry factors used to calculate the stress intensity factors (dimensionless). Jww The J-integral from the applied loads (in.-lb/i. 2). Jm,.ia The material's J-integral fracture resistance (in. lb/in.2), J-R curve. jai The material's J-integral fracture resistance at a ductile flaw growth of 0.10 in. (in.-lb/'in). KI& The mode I stress intensity factor caused by the radial thermal gradient through the cladding applied to