ML19275A344
| ML19275A344 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 09/26/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Tallman W PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| References | |
| NUDOCS 7910040148 | |
| Download: ML19275A344 (4) | |
Text
s v-WW ga nec UP!1TED ST ATES o
NUCLEAR REGULATORY COMMisslON
$
- f,,('
E REGION l d-631 PARK AVENUE
,g j
KING OF PRUSSI A PENNSYLVANIA 19406
,l g
v e
Docket){ast 50-443 50-444 SEP 2 61973 Public Service Company of New Hampshire ATTN:
Mr. W. C. Tallman President 1000 Eln Street Manchester, New Hampshire 03105 Gentlemen:
The enclosed Information Kitice provides information with regard to failures of lube oil coolers for emergency diesel generators.
Sincerely, L
Boyce H. Grier
' Director
Enclosures:
1.
IE Information Notice 79-23 2.
List of IE Information Notices Issued in the Last Six Months cc w/encls:
John D. Haseltine, Project Manager T.100 M 7 i(f 7910040
ENCLOSURE 1 Accession No:
7908220121 SSINS:
6870 JNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Information Notice No. 79-23 Date:
September 26, 1979 Page 1 of 1 EMERGENCY DIESEL GENERATOR LUBE OIL COOLERS Within a two week time span (August 27 to September 11, 1979), the tube sheets failed in the Arkansas Nuclear One (ANO) Unit 1 lube oil coolers for both of the Unit 1 Emergency Diesel Generators.
The introduction of water into the diesel lube oil system resulted in trips of both diesels during surveillance testing.
The diesels were not considered capable of sustained operation.
Investigation by the licensee has indicated cracks around the outer periphery of the tube sheets.
The exact failure mode has not been assessed; however, the licensee has replaced the Emergency Diesel lube oil coolers for both diesels with a cooler of different design.
The original lube oil coolers had tube sheets which were one eighth (1/8) inch in thickness and the tubes were soldered in place.
Epoxy was also used as & sealer on the tube (water side) of the lube oil cooler.
The new coolers have one-half (1/2) inch tube sheets and the tubes are rolled.
The ANO, Unit 1 Emergency Diesel Generators were purchased in 1970 and were manufactured by the Electromotive Division of General Motors Corporation.
The lube oil coolers (Model Number D-191700) were manufactured by Young Radiator Corporation.
This information is provided as an early notification of a possible significant matter.
It is expected that recipients will review the information for possible applicability to their facilities.
No specific action or response is requested at this time.
If further NRC evaluations so indicate, an IE Circular or Bulletin will be issued to recommend or request specific licensee actions.
If you have questions regarding this matter, please contact the Director of the appropriate NRC Regional Office.
t100 0/B
.