ML20032A370
| ML20032A370 | |
| Person / Time | |
|---|---|
| Site: | Phipps Bend  |
| Issue date: | 10/21/1981 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8110290463 | |
| Download: ML20032A370 (2) | |
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4 TENNESSEE VALLEY AUTHORITY-
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/Q CHATTANOOGA, TENNESSEE 37401 400 Chestnut Street Tower II 8/
'0SI Off O/,g 9g* Jo October 21,J1981 PBRD-50-553/81-26 6,
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Mr. James P. O'Reilly, Director Office of Inspection and Enforcement ~
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U.S. Nuclear Regulatory Commission g,,,p*M,,ge Region II - Suite 3100 c,
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Dear Mr. O'Reilly:
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PHIPPS BEND NUCLEAR PLANT UNIT 1 - REPORTABLE DEFICIENCY - FILLET WELD QUALITY CONTROL INSPECTION - PBRD-50-553/81-26 (NCR PBNP-275)
Initial notification of the subject deficiency was made to NRC-0IE, Region II, Inspector P. A. Taylor on August 24, 1981. The first i
interim report was cubmitted.on September 23, 1981. In accordance with paragraph 50.55(e) of 10 CFR Part 50, we are enclosing the final report on the subject aficiency. If you have any questions,
.please call Jim Do e at FTS 857-2014.
r Very truly yours, i
TENNESSE VALLEY AUTHORITY
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L. M. M 11s, Manager Nuclear egulation an Safety Enclosure cc:
Mr. Victor Stello, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555 (V
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P An Equal Opportunity Employer
o ENCLOSURE PHIPPS BEND NUCLEAR PLANT UNIT 1 FILLET WELD QUALITY CONTROL INSPECTION 10CFR 50.55(e) REPORT NO. 2 (FINAL)
PBRD-50-553/81-26 Description of Deficiency Containment wall shell plates have anchor bolt chair assemblies welded to them. The containment wall plates and chairs are welded to the containment base plates. There are 3840 fillet welds used in joining the steel containment walls, the anchor bolt chair assemblies, and the containment base plates. A total of 252 fillet welds were evaluated incorrectly and accepted by Quality Control inspectors based on such
.. incorrect evaluations.
Initial discovery of incorrectly evaluated and accepted fillet welds occurred when Quality Control Investigation Report No. 22372 was written
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on May 14, 1981. It revealed 25 fillet welds undersized. Nonconforming Condition Report PBNP-236 was generated to correct this condition. The NRC letter dated June 30, 1981, contained a Notice of Violation stating that on May 6, 1981, an NRC inspector had discovered two undersized fillet welds. That discovery was assigned Noncompliance Item Number 553/81-05-07.
A reinspection of all 3840 fi[let welds was performed, resulting in discovery that 252 accepted fillet welds were identified as having inadequate weld size, stressrisers, and/or lack of fusion. This NCR was generated to accomplish corrective actions.
The cause of the subject deficiency' appears to be the result of inconsistencies in the inspection method currently employed by our quality control inspectors, i.e.:
1.
The equipment used 2.
The inspection and evaluation process 3
Related repeatability factor of individual inspectors Safety Implications The deficiency, had it remained uncorrected, could have lessened the ability of the containment vessel to withstand design seismic loads.
Therefore, during a design seismic event this condition could have jeopardized the safe operation of the plant.
Corrective Action All undersized fillet welds have had additional filler metal added using qualified welders and procedures. Stressrisers and lack of fusion were corrected by grinding and/or the addition of filler metal. These welds have been reinspected and are now in conformance with drawing and code requirements.
TVA recognizes the need to develoo an effective visual weld inspection training program at the Phipps Bend Nuclear Plant. However, since Phipps Bend is in deferred status, there will be no additional trafG:ng of inspectors at this time. We will forward a copy of this rep set 17 ou.*
Division of Construction QA Staff to alert them to this deficiency.
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