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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
NRC approves NuScale uprated SMR design
NuScale earned approval for its “larger” US460 77-MWe small modular reactor plant design, the Nuclear Regulatory Commission announced last week.
The standard design approval (SDA) is a determination by NRC staff that a reactor design meets the agency’s applicable design requirements, and companies can reference it when applying for a license to build and operate the reactor—but it does not ensure license approval from the commission.
Kosuke Aizawa, Kaoru Fujita, Shingo Hirata, Naoto Kasahara
Nuclear Technology | Volume 183 | Number 1 | July 2013 | Pages 1-12
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-A16988
Articles are hosted by Taylor and Francis Online.
A conceptual design study of Japan Sodium-cooled Fast Reactor (JSFR) is in progress in the Fast Reactor Cycle Technology Development (FaCT) project in Japan. In the design of JSFR, a selector valve mechanism is adopted for its failed-fuel detection and location (FFDL) system. Since JSFR has only two FFDL units for [approximately]600 fuel subassemblies due to its compact design of the reactor vessel, one FFDL unit must handle a much larger number of subassemblies than in previous designs. In addition, during the long plant life of 60 years, the wear length of the selector valve will become longer than those of past reactors. Therefore, the endurance of the selector valve becomes important. To demonstrate the manufacturability and endurance of the selector valve, a full-size mockup valve including coating to protect the sliding mechanism was manufactured, and an endurance experiment of the mockup model under high-temperature sodium was conducted. Dimensional inspections and seal performance showed manufacturability of the selector valve. The cross-section observation, hardness measurement, and chemical assay results after the endurance experiment showed that the coating layer on the sliding surface still remains. Thus, the endurance of the JSFR selector valve was demonstrated.