CANDU pressure tube leak detection by annulus gas dew point measurement: a critical review
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F. R. Greening
Abstract
In the event of a pressure tube leak from a small through-wall crack during CANDU reactor operations, there is a regulatory requirement – referred to as Leak Before Break (LBB) – for the licensee to demonstrate that there will be sufficient time for the leak to be detected and the reactor shut down before the crack grows to the critical size for fast-uncontrolled rupture. In all currently operating CANDU reactors, worldwide, this LBB requirement is met via continuous dew point measurements of the CO2 gas circulating in the reactor's Annulus Gas System (AGS). In this paper the historical development and current status of this leak detection capability is reviewed and the use of moisture injection tests as a verification procedure is critiqued. It is concluded that these tests do not represent AGS conditions that are to be expected in the event of a real pressure tube leak.
Kurzfassung
Für den Fall eines Druckrohrlecks durch einen kleinen Riss während des Betriebs eines CANDU-Reaktors gibt es eine regulatorische Anforderung für den Genehmigungsinhaber – auch bezeichnet als Bruchausschluss-Konzept – um nachzuweisen, dass genügend Zeit vorhanden ist den Riss zu finden und den Reaktor abzuschalten bevor sich der Riss vergrößert und es zu einem Bruch kommt. In den derzeit weltweit betriebenen CANDU-Reaktoren wird diese Anforderung erfüllt mit Hilfe kontinuierlicher Taupunktmessungen des CO2-Gases, das im Gassystem des Reaktors (AGS) zirkuliert. In dem vorliegenden Beitrag wird ein Überblick gegeben über die Entwicklung und den derzeitigen Stand der Leckerkennung. Die Verwendung von Feuchtigkeitsinjektionstests als Verfikationsverfahren wird kritisiert, da diese Verfahren nicht die wahren AGS-Bedingungen darstellen, die man im Falle eines tatsächlichen Druckrohrlecks erwarten kann.
References
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© 2017, Carl Hanser Verlag, München
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Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- CANDU pressure tube leak detection by annulus gas dew point measurement: a critical review
- Multiple regression approach to predict turbine-generator output for Chinshan nuclear power plant
- 10.3139/124.110675
- Development of a parallel processing couple for calculations of control rod worth in terms of burn-up in a WWER-1000 reactor
- Simulation of protected and unprotected loss of flow transients in a WWER-1000 reactor based on the Drift-Flux Model
- Sensitivity analysis for CORSOR models simulating fission product release in LOFT-LP-FP-2 severe accident experiment
- Analysis of the optimal fuel composition for the Indonesian experimental power reactor
- Radiogenic lead from poly-metallic thorium ores as a valuable material for advanced nuclear facilities
- The effects of applying silicon carbide coating on core reactivity of pebble-bed HTR in water ingress accident
- Font Attributes based Text Steganographic algorithm (FATS) for communicating images: A nuclear power plant perspective
- Size control synthesis and characterization of ZnO nanoparticles and its application as ZnO-water based nanofluid in heat transfer enhancement in light water nuclear reactor
- Nuclear characteristics of epoxy resin as a space environment neutron shielding
- Exact solution of the neutron transport equation in spherical geometry
- Technical Notes/Technische Mitteilungen
- Determination of self-attenuation correction factor for lichen samples by using gamma-ray spectrometry
