Document: NUREG-0800
Document ID: 81a2e18b-7311-4c4e-822e-8dfe1b0ba7aa
Document Type: srp
Title: REACTOR PRESSURE VESSEL INTERNALS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0702/ML070230009.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.5
CFR Part: 
CFR Title: 

Content:
tion can encounter adverse flow effects of flow-excited vibrations and acoustic resonances on plant systems and their components. Some plant components, like the steam dryer in a boiling water reactor (BWR) nuclear power plant, perform no safety function but must retain their structural integrity to avoid the generation of loose parts that might adversely impact the capability of other plant equipment to perform safety functions. Adverse flow may also affect the safety function of components like safety relief valves on the BWR main steam lines. The staff reviews the consideration of potential adverse flow effects at BWR and pressurized-water reactor (PWR) nuclear power plants under construction, requesting power uprates, or proposing major plant modifications (e.g., steam generator replacement). The staff’s review includes consideration of the design input parameters and the design-basis loads and load combinations for plant components for normal operation, upset, emergency, and faulted conditions. The review also covers the analytical methodologies, assumptions, computer programs, and code and code edition for the evaluation of the plant components, including the method of determining load definition and the uncertainties and bias errors of analytical and measurement procedures. The review also includes a comparison of the stresses against code allowable limits. NRC acceptance criteria are based on (1) requirements of GDC 1 in Appendix A to 10 CFR Part 50 that structure, system, and components (SSCs) essential to the prevention of accidents that can could affect the public health and safety or to mitigation of their consequences be designed, fabricated, erected, tested, and inspected to quality standards commensurate with the importance of the safety functions performed; (2) requirements of GDC 2 that systems and components essential to the prevention of accidents that can could affect the public health and safety or to mitigation of their consequences be