Document: NRC Regulatory Guide
Document ID: ad61f8a3-1cce-4446-9542-dcdda55c1ec6
Document Type: regulatory_guide
Title: Comprehensive Vibration Assessment Program for Reactor Internals During Preoperational and Initial Startup Testing + HISTORY - HISTORY 07/2015 – DG-1323 , Proposed Revision 4 03/2013 – Periodic Review of Revision 3 – No Issues Identified 11/2006 – DG-1163 , Proposed Revision 3 (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1508/ML15083A390.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.20
CFR Part: 
CFR Title: 

Content:
ponents into a single modular system, additional dynamic excitation might be imparted on the CRDS components. Dynamic excitation because of fluid flow, flow-excited acoustic resonances, and mechanical sources should be addressed in the CRDS design. 2.1 Vibration and Stress Analysis Program The applicant or licensee should perform a vibration and stress analysis for those steady-state and anticipated transient conditions that correspond to preoperational, startup test, and normal operating conditions. The vibration and stress analysis needs to address the structural, hydraulic and acoustic models, analytical and computational formulations, and scaling laws and scale models used in the analysis, including all bias errors and uncertainties for reactor internals that might be adversely affected by FIV, AR, AIV and MIV. Based on operating experience, the analyses need to address the following aspects: a. Identify significant vibration and acoustic resonances caused by various vibration excitation mechanisms that have the potential to damage reactor components, including BWR steam dryers. b. Determine the pressure and force fluctuations and vibration in the applicable plant systems under flow conditions up to and including the full operating power level. Such pressure fluctuations and vibration can result from various excitation mechanisms, such as FIV, AR, AIV and MIV, and need to be assessed for the full range of the plant system fluid flow conditions. In particular, any excitation that is reinforced by structural or acoustic vibration feedback needs to be assessed, and, if necessary, mitigated by design modifications. c. Justify and benchmark the methods used for computing resultant vibration and alternating stress in plant systems. The applicant or licensee should compare stress at locations susceptible to fatigue cracking with the ASME BPV Code fatigue limits to validate the end-to-end analysis. If necessary, the applicant/licensee should perform modifications to the