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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver 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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Michael P. Manahan
Nuclear Technology | Volume 85 | Number 3 | June 1989 | Pages 324-333
Technical Paper | Material | doi.org/10.13182/NT89-A34254
Articles are hosted by Taylor and Francis Online.
Small flakes that consist primarily of magnetite have been discovered on the secondary side of the steam generator of the Three Mile Island Unit 1 plant. These iron oxide flakes are believed to cause significant increases in flow resistance, which in turn causes abnormal increases in steam generator water level. It is necessary to measure the physical properties of the tube scale so that the maximum amount of loose flakes can be generated prior to hydrodynamic cleaning (water slap). It is also important to study the flake properties to shed light on the flake formation and transport mechanisms. Once the physical properties of the tube scale are determined, the effects of hydrodynamic cleaning (water slap) can be optimized by preconditioning the scale. There are several preconditioning options including prewetting, predrying, and thermal cycling of the steam generator tubes. Understanding the physical properties of the scale would also be beneficial in optimizing the water slap technique itself. Elastic modulus, fracture stress, thermal expansion, and swelling of the flakes were measured. With one exception, all of the flakes studied were either one-or two-layered as judged by microstructural variation. The fracture stress of the flake materials tested was in the range of 20.0 to 113.8 MPa (2.9 to 16.5 ksi). There did not appear to be a substantial change in the range of stresses measured at elevated temperatures. There was no evidence of delamination during bend testing. The mean coefficient of linear thermal expansion was a factor of ∼2 larger than that of Fe3O4. The maximum amount of swelling measured was 0.0012%, which is consistent with earlier data on flakes from the Oconee-2 plant.