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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Nuclear new build procurement considerations
It may seem counterintuitive, but the best time to enhance the ability to support operations and maintenance for a new plant is before construction starts. This is one of many lessons learned by the currently operating nuclear fleet. As construction and startup of many nuclear facilities was completed, it quickly became evident that the ability to efficiently support operations and maintenance was limited. Most of the information necessary to establish and manage procurement of spare and replacement items, maintenance, and configuration of the facilities was unavailable and had to be gathered on a case-by-case, “on-demand” basis. Absence of necessary information and the associated challenges resulted in the need for staff augmentation and multiyear-long projects to develop equipment bills of material and maintenance programs and to perform technical evaluations for the huge quantities of spare and replacement items being requested.
D. Elbèze, D. van Houtte, E. Delchambre
Fusion Science and Technology | Volume 75 | Number 5 | July 2019 | Pages 405-411
Technical Paper | doi.org/10.1080/15361055.2019.1603534
Articles are hosted by Taylor and Francis Online.
In the Reliability, Availability, Maintainability, and Inspectability (RAMI) engineering approach used in nuclear fusion research, criticality identifies the failure modes that have the greatest impact on the availability of the studied system. Criticality is expressed as the product of the occurrence level with the severity level of failure modes. The analytical calculation shows that this formulation is equivalent to their availability provided that the duty cycle of basic functions is introduced to adjust the occurrence and the scales of occurrence and severity are homogeneous.
To consolidate the results obtained with a Reliability Block Diagram analysis, we performed a probabilistic study using an advanced Monte Carlo simulation code: the Primavera® Quantitative Schedule Risk Analysis. This method associates failure modes with conditional activities in a schedule and provides the density distribution of failures and tornado graphs to identify the highest criticality failures.
Statistical tests were performed for two operational systems, and we showed that the criticality evaluated with the RAMI approach was in good agreement with the results of the other methods. Thus, in many cases, the analytical formulas can be used during the Failure Mode, Effects, and Criticality Analysis to quickly assess availability by using a spreadsheet.