Document: NUREG-0800
Document ID: 8afa51d9-10c9-4521-a19c-f082a562bcda
Document Type: srp
Title: -
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1602/ML16029A367.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.2.1
CFR Part: 
CFR Title: 

Content:
Draft Revision 4 – April 2016 Examples of materials that are currently used for Class 2 components in the steam generator include the following: Pressure Plates: ASME SA-533, Grade B, Class 1 Bolting: ASME SA-193, Grade B7 Tube Support Structures ASME SA-240, Type 405 and Type 410S (including anti-vibration bars/fan-bars): In summary, for the purposes of satisfying GDC 1 and GDC 30, the materials used in fabricating the steam generator are acceptable if they are selected, fabricated, tested, and inspected (during fabrication/manufacturing) in accordance with the ASME Code. 2. Steam Generator Design The design of the steam generator should limit the potential for degradation so that the integrity of the steam generator, including the tubes, is maintained during the operating interval between inspections. Some degradation mechanisms must be precluded by design since they propagate rapidly or unpredictably, while other degradation mechanisms can be effectively managed through inservice inspections. Degradation of the steam generator tubes and other secondary side components that could affect tube integrity should be manageable through the steam generator program (reviewed under SRP Section 5.4.2.2). Degradation of other steam generator RCPB and SSPB materials should be manageable through the inservice inspection program. The RCPB inservice inspection program is reviewed under SRP Section 5.2.4, while the SSPB inservice inspection program is reviewed under SRP Section 6.6, “Inservice Inspection and Testing of Class 2 and 3 Components.” The steam generator design is acceptable from a degradation standpoint if the design: A. Precludes degradation that propagates rapidly, unpredictably, or in such a manner that it cannot be managed through the inservice inspection program. Rapid and unpredictable degradation includes degradation mechanisms that result from excitation mechanisms, such as fluid-elastic instability. For fatigue, the steam generator tubes and