ML19260C649
| ML19260C649 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 12/20/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Groce R YANKEE ATOMIC ELECTRIC CO. |
| References | |
| NUDOCS 8001080213 | |
| Download: ML19260C649 (1) | |
Text
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DEC 2 01979 Docket No. 50-29 Yankee Atomic Electric Company ATTN:
Mr. Robert H. Grace Licensing Engineer 20 Turnpike Road Westborough, Massachusetts 01581 Gentlemen:
The enclosed Circular 79-25, is forwarded to you for information. No written response to this Circular is required.
If you desire additional information regarding this subject, please contact this office.
Sincerely, O yW$a n Boyce H. Grier Director
Enclosures:
1.
IE Circular No. 79-25 2.
List of Recently Issued IE Circulars CONTACT:
L. E. Tripp (215-337-5282) cc w/encls:
H. Autio, Plant Superintendent L. E. Minnick, President 1702 169 a v 2 )'
ENCLOSURE 1 SSINS:
6830 Accession No: 7910250514 UNITED STATES O
b NUCLkAR rlEGULATORY COMMISSION
.m J u
oo 0FFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Circular No. 79-25 Date: December 20, 1979 Page 1 of 1 SH0CK ARRESTOR STRUT ASSEMBLY INTERFERENCE The Bergen Paterson Pipesupport Corporation reported to the NRC a potential problem with their mechanical shock arrestor
" Strut Assembly." The Bergen Patersc:., Part 2540 Strut Assembly, is being used as a rear bracket for different 7.fzes of Pacific Scientific Company (PSCO) mechanical shock arrestors.
Some of these shock arrestor sizes may not function as intended due to insufficient clearances.
The following problems were identified:
For PSCO shock arrestors sizes 15 and 50, the Bergen Paterson Part 2540 Strut Assembly does not provide sufficient clearance for the shock arrestor to function freely, when installed at an off axis angle greater than 83.
For PSCO shock arrestor size 120 there is insufficient clearance throughout the 180 installation angle.
For PSCO shock arrestor sizes 50 and 120 with Bergen Paterson Adaptor Part 2108 the shock arrestor unit may sustain functional damage when the adaptor unit comes in contact with the rear of the snubber, causing distortion of the end dust cover.
PSCO shock arrestors sizes
.35,
.65, 1.5 and 6 do not have this interference condition and therefore are not part of the potential problem of this circular.
Bergen Paterson stopped shipment as of October 1979 of all Part 2540-15, 2540-50, and 2540-120 strut assemblies and is reviewing all applicable design detail drawings, to identify all affected items and the facilities to which those items have been delivered.
Licensees and holders of construction permits are advised to proceed with the inspection of Pacific Scientific Mechanical Shock Airestor installations with Bergen Paterson Part 2540-15, 2540-50 and 2540-120 Strut Assemblies and deter-mine whether any of the following conditions are applicable:
1.
The shock arrestor installation orientation presents a possible interference problem.
2.
Inspection of shock arrestors 50 and 120 with adaptor show damaged or deformed snubber.
Corrective action should be coordinated with the Sta t Assembly supplier (Bergen Paterson) and appropriate resolutions prom; implemented.
r.
1702 170
ENCLOSURE 2 IE Circular No. 79-25 Date:
December 20, 1979 Page 1 of 1 RECENTLY ISSUED IE CIRCULARS Circular Subject First Date Issued To No.
of Issue 79-16 Excessive Radiation 8/16/79 All Radiography Exposures to Members Licensees Of The General Public And A Radiographer 79-17 Contact Problem in 8/14/79 All Power Reactor SB-12 Switches on Licensees with an Opera-General Electric ting License (0L) or Metalclad Circuit Construction Permit (CP)
Breakers 79-18 Proper Installation of 9/10/79 All Power Reactor Target Rock Safety-Licensees with an OL Relief Valves or CP 79-19 Loose Locking Devices 9/13/79 All Power Reactor Licensees on Ingersoll-Rand Pumps' with an OL or CP 79-20 Failure of GTE Sylvania 9/24/79 All Power Reactor Licensees Relay, Type PM Bulletin with an OL or CP 7305, Catalog SU12-11-AC with a 120V AC Coil 79-21 Prevention of Unplanned 10/19/79 All Power Reactor Licensees Releases of Radioactivity with an OL or CP 79-22 Stroke Times for Power 11/16/79 All Power Reactor Licensees Operated Relief Valves with an OL or CP 79-23 Motor Starters and Con-11/26/79 All Power Reactor Licensees tactors Failed to Op-with an OL or CP erate 79-24 Proper Installation and 11/26/79 All Power Reactor Faci-Calibration of Core Spray lities with an OL or CP Break Detection Equipment on BWRs 1702 17l