ML051520210
| ML051520210 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 05/24/2005 |
| From: | Nuclear Management Co |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| FOIA/PA-2004-0282 | |
| Download: ML051520210 (2) | |
Text
Comments; Questions to May 13, 2004 Internal NMC Memorandum from Charles Tomes to Mark Huting Text at Issue Comment
- Page, ISection,l
-Paragraph Item 1 states that "PBNP conservatively Statement in 1.a. conflicts with Page 1, elected to repair penetration #26 due to:
statement in 1st sentence of 4th
- Summary,
- a. Presence of a large crack like paragraph on page 5 which states Item 1 ultrasonic reflector.
"A.the reflector is related to
- b. Verification through review of fabrication-related geometry and construction records that this area may does not possess characteristics have been repaired during construction, indicative of primary water stress and corrosion cracking." Please
- c. Detection through confirmatory dye correct inaccurate statement.
penetrant examination of small linear Statement in 1.b. indicates review indications."
of construction records. This is not correct. Construction records do not indicate repairs to any J-welds.
please correct inaccurate statement.
0 -2,)
Text at Issue Comment
- Page, Section, Paragraph Item 5 states "Additional dye penetrant examination or eddy current examination of the J-groove welds prior to returning to service are not required or recommended since the structural integrity and leakage integrity has been verified and there is no UT indications that suggest a need for confirmatory PT."
Facts as understood by RiII NRC inspector:
- 1) Two patches of crack-like indications were identified in the nozzle 26 J-weld that were not detected by your UT examination.
- 2) Licensee attributes this cracking in part to residual stress from weld repairs on nozzle 26 (ref page 5 second paragraph item 3).
- 3) Licensee has records to suggest other nozzles have weld repairs (e.g. nozzle 27). However reliance on these records is dubious because they are not official construction/ fabrication records and no basis for identifying a weld repair was given.
- 5) Licensee use of UT data for RPV nozzles to identify J-groove welds which have had repairs may not be accurate. Only nozzles with UT anomalies that extend into the nozzle base material were considered recordable. If weld repairs did not involve removal of nozzle base material, the UT performed would not identify a weld repair.
==
Conclusions:==
These facts strongly suggest that you likely have other similar undetected cracks in other J-groove welds. If these cracks are acceptable from a leakage integrity standpoint, please provide the analysis that demonstrates this cracking cannot grow through the J-groove weld prior to your next outage. (note this document does not provide this assessment).
Page 1,
- Summary, Item 5