Oconee Nuclear Station Unit {number_sign}2 Alloy 600 reactor vessel head CRD penetration inspection: Planning strategies and lessons learned
- Duke Power Co., Charlotte, NC (United States). Engineering Support Div.
Leakage from an Electricite de France (EdF) PWR reactor vessel head penetration at Bugey Unit {number_sign}3 was discovered during a hydrostatic test in 1991. The penetration material is Inconel 600 and is common to many other reactor vessel penetrations throughout the world. EdF has reported the cause of the leakage to be a throughwall crack resulting from Primary Water Stress Corrosion Cracking (PWSCC) as determined by metallurgical evaluation. Utilities in Sweden, Japan, Switzerland, Belgium and Spain have also completed inspections of penetrations in the reactor vessel heads. Cracking has been identified in approximately four percent of the additional EdF penetrations inspected and two percent of worldwide penetrations inspected to date. Five US nuclear plants have completed inspections of the control rod drive (CRD) penetrations with two plants finding indications. D.C. Cook and Oconee Nuclear Stations completed inspections in 1994 with each utility identifying one penetration with multiple indications. Point Beach, Palisades, and North Anna Nuclear Stations have completed penetration inspections without identifying any indications. This paper discusses the planning and preparation for the inspection of the CRD penetrations at ONS Unit {number_sign}2.
- OSTI ID:
- 403316
- Report Number(s):
- CONF-960706--; ISBN 0-7918-1782-2
- Country of Publication:
- United States
- Language:
- English
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