Document: NUREG-0800
Document ID: 495c2b41-2832-4900-9000-040f3ae8c835
Document Type: srp
Title: STEAM GENERATOR MATERIALS AND DESIGN
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1614/ML16147A289.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.2.1
CFR Part: 
CFR Title: 

Content:
Part 50; the requirements of Appendices B and G to 10 CFR Part 50; and the requirements of 10 CFR 50.55a. This conclusion is based on the staff’s review of the SAR. Degradation that propagates in a manner such that it cannot be managed through the inservice inspection program has been precluded by design. The materials used in the fabrication of the steam generator have been identified and comply with the requirements of 10 CFR 50.55a. (For those materials not allowed by Section III of the ASME Code, the materials were reviewed on a case-by-case basis and determined to be acceptable, consistent with the provisions of 10 CFR 50.55a(a)(3).)* *Indicates material within parentheses “as applicable.” 5.4.2.1-17 Revision 4 - July 2016 2. The primary side of the steam generator is designed and fabricated to comply with ASME Class 1 criteria, and fatigue is addressed per Regulatory Guide 1.207. The secondary side of the steam generator is designed and fabricated to comply with ASME Class 2 criteria. (The SSPB parts of the steam generator will be designed, manufactured, and tested to ASME Class 1 criteria, although the staff-required classification is ASME Class 2.)* 3. The crevice between the tubesheet and the inserted tube will be limited because the tube will be expanded to the full depth of insertion of the tube in the tubesheet. The tube expansion and subsequent positive contact pressure between the tube and the tubesheet will preclude any buildup of impurities from forming in the crevice region and will reduce the probability of crevice boiling. The tube-to-tubesheet welds comply with ASME Class 1 criteria. The feedwater inlet design, including the feedring, uses materials and design features that resist degradation from flow-accelerated corrosion, water hammer, and thermal stratification. (The tube support plates will be manufactured from ferritic or martensitic stainless steel material, which laboratory tests have shown to be corrosion resistant to the