Document: NRC Regulatory Guide
Document ID: a1541707-8144-409c-8842-4ea7d4b8ef4e
Document Type: regulatory_guide
Title: 10/2019 (Rev. 19)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1912/ML19128A244.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.147
CFR Part: 
CFR Title: 

Content:
50.55a(z). (3) For Class 1 piping that does not meet the criteria of Figure-3221, the use of evaluation methods and criteria is subject to NRC review and approval under 10 CFR 50.55a(z). (4) For those components that do not require immediate repair or replacement, the rate of wall-thickness loss is to be used to determine a suitable inspection frequency so that repair or replacement occurs prior to reaching the allowable minimum wall thickness, tmin. (5) For corrosion phenomena other than flow-accelerated corrosion, use of the Code Case is subject to NRC review and approval. Inspection plans and wall-thinning rates may be difficult to justify for certain degradation mechanisms such as MIC and pitting. (6) The evaluation criteria in Code Case N-513-2 may be applied to Code Case N-597-2 for temporary acceptance of wall thinning (until the next refueling outage) for moderate-energy Class 2 and 3 piping. Moderate-energy piping is defined as Class 2 and 3 piping whose maximum operating temperature does not exceed 200 °F (93 °C) and whose maximum operating pressure does not exceed 275 psig (1.9MPa). Code Case N-597-2 shall not be used to evaluate through-wall leakage conditions. RG 1.147, Rev. 19, Page 36 CODE CASE NUMBER TABLE 5 SECTION XI CODE CASES THAT HAVE BEEN SUPERSEDED DATE N-606 Similar and Dissimilar Metal Welding Using Ambient Temperature Machine GTAW Temper Bead Technique, Section XI, Division 1 N-606-1 Published on 9/24/99 N-606-1 Similar and Dissimilar Metal Welding Using Ambient Temperature Machine GTAW Temper Bead Technique for BWR CRD Housing/Stub Tube Repairs, Section XI, Division 1 Prior to welding, an examination or verification must be performed to ensure proper preparation of the base metal, and that the surface is properly contoured so that an acceptable weld can be produced. This verification is to be required in the welding procedures. N-606-2 Published on 8/13/13 N-609 Alternative Requirements to Stress-Based Selection Criteria for Category B-J