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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.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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Latest News
NRC restores expiration dates for renewed Turkey Point licenses
The Nuclear Regulatory Commission announced this week that it has restored the expiration dates of the Turkey Point nuclear power plant's units 3 and 4 subsequent license renewals (SLR) to July 19, 2052, and April 10, 2053, respectively.
Raymond K. Maynard, Tushar K. Ghosh, Robert V. Tompson, Dabir S. Viswanath, Sudarshan K. Loyalka
Nuclear Technology | Volume 172 | Number 1 | October 2010 | Pages 88-100
Technical Paper | Materials for Nuclear Systems | doi.org/10.13182/NT10-6
Articles are hosted by Taylor and Francis Online.
An experimental system was constructed in accordance with the standard ASTM C835-06 to measure the total hemispherical emittance (emissivity) of structural materials of interest in very high temperature reactor (VHTR) systems. First, data were acquired for 304 stainless steel as well as for oxidized and unoxidized nickel, and good reproducibility and agreement with the literature was found. Emissivity of Hastelloy X was then measured under different conditions that included (a) "as received" (original sample) from the supplier, (b) with increased surface roughness, (c) oxidized, and (d) graphite coated. Measurements were made over a wide range of temperatures. Hastelloy X, as received from the supplier, was cleaned before additional roughening of the surface and coating with graphite. The emissivity of the original samples (cleaned after received) varied from [approximately]0.18 to 0.28 in the temperature range of 473 to 1498 K. The apparent emissivity increased only slightly as the roughness of the surface increased (without corrections for the increased surface area due to the increased surface roughness). When Hastelloy X was coated with graphite or was oxidized, however, its emissivity was observed to increase substantially. With a deposited graphite layer on the Hastelloy, increases from 0.2 to 0.53 at 473 K and from 0.25 to 0.6 at 1473 K were observed - a finding that has strong favorable safety implications in terms of decay heat removal in postaccident VHTR environments. Initial oxidation of Hastelloy X surfaces was observed to notably increase the emissivity of the Hastelloy X but was not observed to progress significantly beyond the initial oxidation even with more prolonged exposure. Since there is likely to be initial surface oxidation of any Hastelloy X used in the construction of VHTRs, this represents an essentially neutral finding in terms of the safety implications in postaccident VHTR environments.