ML17053B309
| ML17053B309 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 12/20/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Rhode G NIAGARA MOHAWK POWER CORP. |
| References | |
| NUDOCS 8001080176 | |
| Download: ML17053B309 (6) | |
Text
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Docket No. 50-410 DEC 20 1979 UNITED STATES NUCLEAR REGULATORY COMMISSION REGION I 631 PARK AVENUE KING OF PRUSSIA, PENNSYLVANIA19406
~7<~ FccCr Niagara Mohawk Power Corporation ATTN:
Mr.
G.
K.
Rhode Vice President System Project Management 300 Erie Boulevard, West
- Syracuse, New York 13202 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, Boyce H. Grier Director
Enclosures:
l.
IE Circular No. 79-25 2.
List of Recently Issued IE Circulars CONTACT:
L.
E. Tripp (215-337-5282) cc w/encls:
Eugene B. Thomas, Jr.,
Esquire go/8 80 0 1080
ENCLOSURE 1 S SINS:
6830 Accession No: 7910250514 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT MASHINGTON, D. C.
20555 SHOCK ARRESTOR STRUT ASSEMBLY INTERFERENCE IE Circular No. 79-25 Date:
December 20, 1979 Page 1 of 1 The Bergen Paterson Pipesupport Corporation reported to the NRC'a potential problem with their mechanical shock arrestor - "Strut Assembly."
The Bergen
- Paterson, Part 2540 Strut Assembly, is being used as a rear bracket 'for different sizes 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'nstallation 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 Arrestor installati'ons 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 ar restor 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 Strut Assembly supplier (Bergen Paterson) and appropriate resolutions promptly implemented.
ENCLOSURE 2 IE Circular No. 79-25 Date:
December 20, 1979 Page 1 of 1 Circular No.
Subject RECENTLY ISSUED IE CIRCULARS First Date Issued To of Issue 79-16 79"17 Excessive Radiation Exposures to Members Of The General Public And A Radiographer Contact Problem in SB-12 Switches on General Electric Metalclad Circuit Breakers
- 8/16/79 8/14/79 All Radiography Licensees All Power Reactor Licensees with an Opera-ting License (OL) or Construction Permit (CP) 79"18 79-19 79-20 79-21 79-22 79"23 79"24 Proper Instal lation of 9/10/79 Target Rock Safety-Relief Valves Loose Locking Devices
.9/13/79 on Ingersoll-Rand Pumps Failure of GTE Sylvania 9/24/79
- Relay, Type PM Bulletin 7305, Catalog 5U12-ll-AC with a 120V AC Coil Prevention of Unplanned 10/19/79 Releases of Radioactivity Stroke Times for Power ll/16/79 Operated Relief Valves Motor Starters and Con-ll/26/79 tactors Failed to Op-erate Proper Installation and 11/26/79 Calibration of Core Spray Break Detection Equipment on BWRs All Power Reactor Licensees with an OL or CP All Power Reactor Licensees with an OL or CP All Power Reactor Licensees with an OL or CP All Power Reactor Licensees with an OL or CP All Power Reactor Licensees with an OL or CP All Power Reactor Licensees with an OL or CP All Power Reactor Faci-lities with an OL or CP