Document: NUREG-0800
Document ID: 7c7e043f-0cf6-4d85-ad06-3f01128bc7f8
Document Type: srp
Title: (ENiCrFe-7), and 5.14 (ERNiCrFe-7)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0703/ML070380192.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.11
CFR Part: 
CFR Title: 

Content:
Pressure Boundary Welds: Low Alloy Steel, SFA 5.5, 5.23, 5.28 5.4.2.1-6 Revision 3 - March 2007 Manway Studs: ASME SA-193, Grade B7 Manway Nuts: ASME SA-194 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 antivibration 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. 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 pressure boundary materials should be manageable through the inservice inspection program (the RCPB inservice inspection program is reviewed under SRP Section 5.2.4). The steam generator design is acceptable from a degradation standpoint if it accomplishes the following: A. Limits the crevice between the tube and the tube supports. This can be accomplished by using openings of various shapes (e.g., trifoil or quatrefoil) in tube support plates or by using lattice grid (eggcrate) tube supports. The design of the tube supports should promote high-velocity flow along the tubes. Limiting the crevices will limit the buildup of corrosion product and sludge, which can lead to corrosion of the tubes and the supports. B. Uses appropriate corrosion-resistant materials or employs cladding for materials susceptible to