The Use of OPEX (in the Form of Inspection Data) to Obtain Unanticipated Calandria Tube (CT) Ovality Measurements
9th International Conference on CANDU® Maintenance - 2011 December 04-06

Presented at:
9th International Conference on CANDU® Maintenance
2011 December 04-06
Toronto, Canada
Session Title:
Learning from OPEX Session A3

Paul J. Sedran (Canadian Power Utility Services Ltd.)
Bill Rankin (New Brunswick Power Nuclear)


For fuel channel deformation studies, inspections are an essential source of OPEX and are used to generate specific data, such as pressure tube dimensions.  However, additional unintended information can be extracted from raw inspection data.  This paper presents examples of the generation of CT inner diameter profiles using data from the inspections of  L1F06 and G2F14  to illustrate how inspection/OPEX data can contain significant hidden information.

In the CT diameter profiles for L1F06 and G2F14, it was found that spacer loading produced significant local ovality in the CT and that the resultant gap reduction is consistent with the predictions of the existing deformation models.  

The finding of significant local CT ovality is corroborated by CT gauging measurements reported by S.A. Donahue in 2008.

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