ML19275A204
| ML19275A204 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 09/13/1979 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Pilant J NEBRASKA PUBLIC POWER DISTRICT |
| Shared Package | |
| ML19275A205 | List: |
| References | |
| NUDOCS 7910030315 | |
| Download: ML19275A204 (1) | |
Text
- 3. a re, CENTRAL FILES
'o UNITED STAT ES PDR:HQ j' y,
',,g NUCLEAR REGULATORY COMMISSION R
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,i g REGION IV o, S4 g
611 HYAN l'LAZA DRIVE, CUITE 1000 U
ARLINGTON,TEXAG 76012 o
September 13, 1979 Docket No.
50-298 Nebraska Public Power District ATTN:
J. M. Pilant, Director Licensing & Quality Assurance Post Office Box 499 Columbus, Nebraska 68601 Gentleman:
The enclosed IE Circular No. 79-19, is forwarded to you for information.
No written response is required.
Should you have any questions related to your understanding of this matter, please contact this office.
Sincerely,
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Director
Enclosures:
1.
IE Circular No. 79-19 2.
List of IE Circulars Issued in the Last 6 Months cc:
L. C. Lessor, Superintendent Cooper Nuclear Station Post Office Box 98 Brownville, Nebraska 63321 een 791ooso 3I C Q
4
UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C.
20555 gg g IE Circular No. 79-19 Date:
September 13, 1979 Page 1 of 2 LOOSE LOCKING DEVICES ON INGERSOLL-RAND PUMP IMPELLERS Description of Circumstances:
Three reports have been submitted to the NRC regarding the loosening of locking devices on the impellers' of pumps manufactured by the Ingersoll-Rand Company.
The first report was submitted as a significant deficiency (10 CFR 50.55(e))
by Arkansas Power and Light Company in letters of O rch 17, 1978, and May 9, 1978. The licensee reported excessive noise and vibrations in both Low Pressure Safety Injection (LPSI) pumps during the preoperational test program on Unit 2 of Arkansas Nuclear One (ANO).
It was discovered that the washers, jam nut and cap nut used to retain the impellers were missing on both pumps (Ingersoll-Rand Type 8X20WD). The licensee's corrective action involved the installation of a tab washer. This corrective action was, also, taken on the containment spray pumps (Ingersoll-Rand Type 6X23WD) because of similarity of design.
The second report was submitted by Duke Power Company in a licensee event report (LER 50-287/78-23) dated January 24, 1979. The symptoms were similar to those observed at ANO Unit 2 in that high vibration was detected in a reactor building spray pump (Ingersoll-Rand Type 4X11A) for Oconee Unit No. 3.
The licensee found that the impeller had worked loose. The corrective action included a revision to the maintenance procedure to specify torque requirements.
The third report was 10 CFR 21 Report No. 79-01 submitted by Portland General Electric Co. on April 16, 1979. This report identified a deficiency that may exist in the Trojan Nuclear Plant containment spray pumps (Ingersoll-Rand Type 6X23WD) in that there is a potential for the impeller lock nut to loosen. The potential deficiency was identified because of the similarity of the containment spray pumps design to the residual heat removal (RHR) pumps (Ingersoll-Rand Type 8X20WD) and the discovery of a loose lock nut on an RHR pump during pump maintenance. The corrective action was to provide a positive mechanical lock on the impeller nut.
Westinghouse Nuclear Service Division has issued a Technical Bulletin to Westing-house plant owners un loose lock nuts on Ingersoll-Rand Types W, WD, and WDF pumps. Excerpts from that Technical Bulletin are in Enclosure No. 1.
Combustion Engineering, Inc. has, also, informed th i
same problem in a letter dated March 13, DUPLICATE DOCUMENT 1P",_)
'l J 7
Enclosure No. 2.
IL Entire document previously entered into system under:
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ANO No. of pages:
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