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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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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Fusion Science and Technology
Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
D.K. Murdoch, F. Olezza, J-L. Mazel
Fusion Science and Technology | Volume 21 | Number 2 | March 1992 | Pages 966-970
Material; Storage and Processing | doi.org/10.13182/FST92-A29876
Articles are hosted by Taylor and Francis Online.
Large diameter (up to approx. 2 m) tritium compatible vacuum valves will be required for a broad range of applications around the NET/ITER torus. This paper focuses on the development steps and current design status of the valves located immediately upstream of the torus primary vacuum pumps. The number (24) and size (1500 mm nominal diameter) of these valves has been established in studies of the required particle exhaust rate from the torus and the conductance of the divertor duct and manifold system. The three principal functions are to isolate the torus during maintenance, to prevent back-streaming during regeneration of compound cryopumps, and to provide fast closure following accident or upset conditions. The design input parameters are tabulated in the paper. Initial engineering studies indicate that a gate valve is the preferred configuration to achieve low conductance losses and a design compatible with the confined space available. In order to meet the specified internal leak tightness (10−4 Pa.m3. s−1) in the potentially dust-laden environment, an elastomeric sealing material is recommended. This will keep the sealing forces and therefore the overall weight and dimensions of the valve within acceptable limits. Because of the arduous operating environment (dust, tritium, neutron activation and high operating frequency) provision will be made for change-out of the valve seals as a routine maintenance activity. A valve design in which the bonnet, stem and valve disc (along with the elastomer seal rings) can be removed from the valve body by a remotely operated manipulator and transferred to a centralized hot cell location for refurbishment has therefore been specified. Development of the valve includes both engineering studies and laboratory test work, and these are described in the paper. A prototype valve will be available in 1995–96 for incorporation into an integrated vacuum system test loop.