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:
or collecting plant data during power ascension and full licensed power conditions. As the steam dryer is not a Code component, the applicant/licensee may justify different stress acceptance criteria. 4. PWR Steam Generator Stress and Design Margin. An applicant for the construction and operation of a PWR nuclear power plant and a licensee proposing a power uprate or planning a major plant modification at an operating PWR nuclear power plant is expected to evaluate the dynamic response, stress, and design margin of the internal components in the steam generators. This evaluation is expected to address potential adverse flow effects caused by flow-excited vibrations and acoustic resonances on the steam generator tube bundle, moisture separator, steam dryer, main steam piping, and safety valves. Past operating experience and analysis may support the determination of adequate design margin for the stress on PWR steam generator internal components. 5. Evaluation of Other Plant Components. An applicant for the construction and operation of a nuclear power plant and a licensee of an operating BWR or PWR nuclear power plant proposing a power uprate license amendment or to implement a major plant modification are expected to evaluate potential adverse effects from pressure fluctuations and vibration on piping and components of plant systems, including the reactor coolant, steam, feedwater, and condensate systems, up to full proposed operating conditions. These plant components include safety relief valves, power-operated valves, and sampling probes. Experience indicates that particular attention should be paid to cantilevered piping and components. For example, steam flow over the opening of a safety valve standpipe and feedwater flow around the sampling probes may excite acoustic resonances or cause flow-induced vibration that can damage associated components (valves, steam dryer, or pipes). The applicant/licensee is expected to make any necessary modifications to plant