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:
bly • steam dryer assembly • feedwater spargers • standby liquid control header and spargers and piping • RPV vent assembly • core plate • top guide • control rod drive housing and guide tube • orificed fuel support • jet pump and support • shroud and shroud support • core plate and reactor pump differential pressure lines • in-core monitoring housing system/in-core guide tubes and stabilizers For PWR nuclear power plants, reactor internals might include the following components: • core barrel • upper core support assembly • lower core support assembly • control rod guide assembly DG-1323, Page 6 • in-core instrumentation guide tubes • flow distribution device • heavy reflector • irradiation specimen baskets For SMRs, reactor internals might include the following components because of their location inside the integral RPV module, even though some components might not be traditionally classified as reactor internals. • reactor coolant/recirculation pumps • riser • SGs • pressurizer • CRDMs and supports • feedwater lines Although this regulatory guide applies to reactor internals, it provides guidance that could be helpful for the evaluation of potential adverse effects on SG internals and tubes in PWRs. This regulatory guide discusses activities separate from inservice inspection and inservice testing programs established in compliance with 10 CFR 50.55a, “Codes and Standards.” History of Revisions The original guidelines of RG 1.20 (dated December 1971) served as the basis for testing many prototype and “similar-to-prototype” (referred to in this guide as “limited prototype” or “non-prototype”) reactor internals. However, operating experience and the tendency for the design of subsequent reactor internals to differ from that of the initially designated prototypes made the basic prototype and non-prototype classifications difficult to apply, resulting in the need for time-consuming case-by-case