ML20236A748
| ML20236A748 | |
| Person / Time | |
|---|---|
| Issue date: | 03/10/1989 |
| From: | Baker E, Cilimberg R Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20236A700 | List: |
| References | |
| REF-QA-99900005 NUDOCS 8903200146 | |
| Download: ML20236A748 (4) | |
Text
a ORGANf2ATION: WESTINGHOUSE ELECTRIC CORPORATION COMMERCIAL NUCLEAR FUEL DIVISION PITTSBURGH, PENNSYLVANIA l
REPORT INSPECTION INSPECTI0li NO.: 99900005/88-01 DATE:
12/14-15,1988 ON-SITE HOURS:
16 CORRESPONDENCE ADDRESS: Mr. Mead D' Amore, General Manager Westinghouse Electric Corporation Comercial Nuclear Fuel Division Post Office Box 355 Pittsburgh, Pennsylvania 15230 ORGANIZATIONAL CONTACT: Mr. R. Cost, Manager of Quality Assurance TELEPHONE NUMBER:
(412)374-2359 l
HUCLEAR INDUSTRY ACTIVITY:
Nuclear fuel assembly supplier for Westinghouse, General Electric, and Combustion Engineering designed reactors.
L M
SkU ASSIGNED INSPECTOR:
R. L. Cilimberg, Reactive Inspection Section No. 1 Date OTHERINSPECTOR(S):
None
/0!ff APPROVED BY:
.9 E. T. Baker, Section Chief, RIS-l', Vendor Inspection Date Branch INSPECTI0t BASES Afl0 SCOPE:
A.
BASES:
10 CFR 50, Appendix B and 10 CFR 21 B.
SCOPE:
Review records pertaining to the manufacture of hafnium control rods for rod cluster control-assemblies (RCCAs) for Wolf Creek, Callaway, and Maanshan (Taiwan).
2 PLANT SITE APPLICABILITY: Wolf Creek (50-482), Callaway (50-483), Maanshan (Taiwan), and other reactor facilities with fuel supplied by Westinghouse.
8903200146 890314 00 b
1 ORGANIZATION: WESTINGHOUSE ELECTRIC CORPORATION COMMERCIAL NUCLEAR FUEL DIVISION' PITTSBURGH, PENNSYLVANIA REPORT INSPECTION NO.: 99900005/88-01 RESULTS:
PAGE 2 of 4 A.
VIOLATIONS:
None B.
NONCONFORMANCES:
None C.
UNRESOLVED ITEMS:
None D.
STATUS OF PREVIOUS INSPECTION FINDINGS:
l
)
Not applicable.
E.
INSPECTION FINDINGS AND OTHER COMMENTS:
1.
The Nuclear Regulatory Commission (NRC) staff informed Westinghouse (W) management representatives of the scope of the inspection during the entrance meeting on December 14, 1988, and l
summarized the inspection findings during the exit meeting on December 15, 1988.
===2.
Background===
Karl Hurst,tianager of RCS Components Licensing and other W staff advised the NRC by telephone on November 23, 1988, of a haTnium swelling incident that was discovered during eddy current (EC) testing of RCCAs at Wolf Creek. The EC testing was performed by Combustion Engineering to measure wear between the control rod cladding and the guide tube.
During the testing, bump anomalies were discovered in the 304 stainless steel cladding on the control rods. W believes that the swelling of the cladding is caused by hydriding of the hafnium by hydrogen which evolvea from the reactor coolant and diffused through the stainless steel cladding. W estimates that the swelling thattcould result from i
I complete hyHriding of the hafnium would causeln increase in scram time that is still below the Wolf Creek tichnical specification., The NRC inspection discussed in Sections 3 and 4 of this report did not identify any nonconformances with requirements for hafnium rod traceability and certification, and stated that the hafnium swelling was not related to manufacturing.
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l ORGANIZATION: WESTINGHOUSE ELECTRIC CORPORATION COMMERC1AL NUCLEAR FUEL DIVISION PITTSBURGH, PENNSYLVANIA REPORT INSPECTION N0.: 99900005/88-01 RESULTS:
PAGE 3 of 4 3.
Document Review The inspector reviewed the computer lists in the W hafnium rod traceability system to determine what hafnium rodi were used to manufacture the RCCAs which exhibited swelling in Maanshan 1, Wolf Creek, and Callaway. Hafnium ingot analysis and final product chemistry for 960 pieces of hafnium supplied to'W by Western Zirconium Incorporated was selected at random for detailed review.
The inspector determined that the certified data met W requirements for hafnium chemistry i
including a hydrogen specification of 60 parts per million (maximum).
The same quality material was used to manufacture the RCCAs for Maanshan 1, Wolf Creek, and Callaway. The document review did not identify any deviations from W QA program requirements.
4.
Hafnium Sweeling The inspector met with Howard Menke, W Manager of Product Design to discuss what W had described as bump anamolies in RCCAs inspected during the third refueling outage at Wolf Creek. Mr. Menke summarized the information contained in a December 8, 1988, letter to C. E. Rossi of the NRC from Mr. W. J. Johnson, Manager of the W Nuclear Safety Department. W reviewed all manufacturing and asseiEbly procedures as well as the f5brication inspection requirements for hafnium RCCAs.
W concluded that inspecticn would have detected any as-built defects,
{
therefore, manufacturing was considered to be an unlikely contributor to the bump anamolies.
l Hafnium hydriding was identified as the most likely mechanism which led to the conditions reported at Wolf Creek.
Hydriding occurs when hydrogen comes in contact with hafnium.
Hydrogen from the reactor coolant diffuses through the stainless steel cladding and reacts with the hafnium to form hafnium hydride.
The results of the W investigation of the hafnium localized swelling phemomena covers alt W supplied nuclear plants which use this type material and new information is currently being reported to the NRC.
W has reconnended continued operation of affected plants through three eighteen month or four annual cycles since W believes that current information does not indicate the existence of a substantial safety hazard.
ORGANIZATION: WESTINGHOUSE'E ELECTRIC CORPORATION COMMERCIAL NUCLEAR FUEL DIVISION PITTSBURGH,. PENNSYLVANIA REPORT -
. INSPECTION NO.: 99900005/88-01 RESULTS:
PAGE 4 of 4 F.
PERSONS CONTACTED:
- W. Hartnett
- J. Higginbotham
- H. Menke
- R. Pollard i
- L. Reiland
- R. Ripley. Union Electric i
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- Attended exit meeting.
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