IR 05000320/1977045
| ML19220B265 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 12/02/1977 |
| From: | Haynes R, Walton G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML19220B263 | List: |
| References | |
| 50-320-77-45, NUDOCS 7904250557 | |
| Download: ML19220B265 (3) | |
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U.S. NUCLEAR ?.EGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT Region I Report No. en_,onf77_ac Docket No. 50-3?O License No. qpp_ge Priority
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Category B
Licensee:
% trocolitan Edison Comoany P. O. Box 542 Readino, Pennsylvania 19602 Facility Name:
Three Mile Island Nuclear Station, Unit 2 Inspection at:
Middletown, Pennsylvania Inspection conducted: November 23, 1977 Inspectors:
8, &/[/gb hp 7/o77
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da te' s i gne'd G. Walton, Reactor Inspector date signed date signed Approved by:
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cate signec R. Haynes, Chiet, Engineering Support Section No.1 RC&ES Branch Inspection Summary:
Insoection on November 23,1977 (Recort No. 50-320/77-45)
Areas Insoected:
Routine, announced inspection of preservice examinations on steam ganerator tubes. The inspection involved 3.5 inspector-hours by one NRC incpector.
Results: Of the one area inspected, no items of noncompliance were identified.
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Region I Fom 12 74'jf,;S
(Rev. April 77)
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i904250657
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DETAILS 1.
Persons Contacted General Public Utilities Service Corcoration
- R. F. Fenti, Lead Site Q.A. Auditor D. G. Slear, Mechanical Engineer S. Levin, Project Engineer
- Present at the exit interview.
Eddy Current Inscection of Steam Generator Tubes 2.
The inspector reviewed the licensee's program fcr establishing a The program has preservice record on the steam generator tubes.
been expanded to inspect 100 percent of both A and B steam generator tubes and present plans are to remove tubes to verify results of inspection findings.
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At present all of the tubes in the A generator have been inspected A
using the eddy current method from the inside of the tubes.
frequency of 400KHz was used to increase et ide surface sens-i ti vity.
The results of the A generator are as follows.
Eight tubes were found with a phase shif t which indicates wall reduction greater than 40 percent thru wall.
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Ten tubes were found with high amplitude signal and a phase shif t which indicates a reduction less than 20 percent thru
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wall.
Four hundred tubes were found with mechanical dents of 1 to 3
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mils deep.
Some tubes appear to have a reduction of the inside diameter and will not allow passage of the eddy current probe.
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The licensee plans to remove one tube of each of the conditions described above (4 total) to determine the validity of the test
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results and the cause of the wall reduction.
The licensee will then determine disposition of the tubes.
The indications are randcmly oriented except fcr these tubes having wall reductions greater than 40 percent.
These indications are generally located 42 inches above the bottcm of the tubes (between the bottcm tube sheet and the first tube support).
The mechanical dents are randemly scattered throughcut the steam generator.
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The licensee is continuing examination of tne B generator.
This item is considered to be t.iresolved pending further inspection and examinations by the licensee to determine the cause and corrective actions required.
(320/77-45-01)
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Unresolved Items Areas for which more information is required to determine acceptablity are considered unresolved. An unresolved item is contained in paragraph 2 of this report.
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Exit Interview At the conclusion of the inspection on November 23, 1977, the inspector met with a licensee representative (denoted in paragraph 1) to discuss the inspection scope and findings.
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