FPL Energy Duane Arnold makes the following notification under
10 CFR 21.21(d)(3)(i) of a defect found during
snubber rebuild activities. The specific defect is foreign materials identified in the
GE SF 1154
snubber fluid, which was supplied by Shaw A/DE, Inc (now known as Fronek
Anchor Darling Enterprises, Inc.) as a basic component in 2003. The fluid has been identified as a part of
GE batch number AD965 and was manufactured June 2001.
The foreign material had the appearance and texture of paraffin wax. FPL Energy has postulated that the foreign material could restrict fluid flow through the orifice in the snubber and cause the snubber to remain locked following activation. The resulting locked snubber would prevent the function of allowing for some piping movement associated with normal system movement.
The fluid has been removed from use at the Duane Arnold Energy Center (DAEC) and a portion was sent for analysis. The analysis indicates that the solid contaminate is silicone. Silicone based oils are generally very stable and the analysis does not indicate how, or why, they came out of solution. FPL Energy engineering personnel inquired about the analysis findings to ascertain the likely causes for the silicone separation from solution. The conclusion is that it could have been a bad batch, a contaminant could have been introduced during processing or repackaging or it could have resulted from some form of reaction with the plastic container.
The supplier, Fronek Anchor Darling Enterprises, Inc, was contacted on 12/22/06 to discuss FPL Energy Duane Arnold's findings.
FPL Energy has verified that none of the suspect batch has been installed in snubbers installed at the DAEC. All the suspect fluid has been accounted for.
It is unknown if any fluid from this same lot was distributed to any other power reactor sites.
The licensee notified the NRC Resident Inspector.
