ML19224C444
| ML19224C444 | |
| Person / Time | |
|---|---|
| Site: | Atlantic Nuclear Power Plant  |
| Issue date: | 06/20/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Collier A OFFSHORE POWER SYSTEMS (SUBS. OF WESTINGHOUSE ELECTRI |
| References | |
| NUDOCS 7907020371 | |
| Download: ML19224C444 (1) | |
Text
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e nc UNITED STATES
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NUCLEAR REGULATORY COMMISSION REGION ll
{.g ' O f E 101 M ARIETT A ST., N.W., SUIT E 3100 o,
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AT L ANT A, GE oRGI A 30303 Av JUN 2 01979 In Reply Refer To:
RII:JP0 50-437 O'fshore Power Systems Attn:
A. R. Collier, President P. O. Box 8000 Jacksonville, Florida 32211 Gentlemen:
This Information Notice is provided as an early notification of a possibly is expected that recipients will review the informa-significant matter. It No specific actfon or tion for possible applicability to their facilities.If further NRC evaluations so indicate, response is requested at this time.
an IE Circular or Bulletin will be issued to recorm nd or request specific If you have questions regarding this matter, please contact licensee actions.
the Director of the appropriate NRC Regional Office.
Sincerely, p James P. O'Rei Director
Enclosures:
1.
IE Information Notice No. 79-17 2.
List of Information Notices Issued in 1979 271 246 790702637/
Y UEITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 June 20, 1979 IE Information Notice No. 79-17 SOURCE HOLDER ASSEMBLY DAMAGE FROM MISFIT BETWEEN GRID PLATE Description of Circumstances:
Recently, the NRC was infor=ed of a problem at two Westinghouse PWR f aci resulting from an apparent misfit between secondary source holder asse blies and the reactor upper grid plate.
identified by Carolina Power & Light, licensee The misfit problem was first for H. B. Robinson Unit 2, who inforced the NRC on May during the mined that two secondary source holder assemblies had been damaged stances.
d the previous refueling in February 1978, by a misfit between the asse=
(i.e.1/2 to 3/4 inch) between the source holder assembly hub and the grid reactor upper grid plate.
This lack plate at the core locations containing thermocouple mixing v The deforma-ponents at the core location and of the source holder asse
- however, i
in no case did this bending result in fuel cladding perforat or 1 informed the NRC that the On May 16, 1979, the licensee af D. C. Cook Unit present refueling outage vould be extended 15 to 20 They learned of the proble= from Westinghouse.
correct this misfit problem.
Subsequently, the licensee's inspection revealed that the source holderThe s assembly hubs were in contact with the vanes.from one asse b source holder was found stuck in the assembly.
prior to return to operations.
The secondary source asse=bly rods are nomally inserted into rod cluster Each si.ch syc:netrical locations in the core.
control assemblies and placed at d
d asse=bly contains a syr:=etrical grouping of four secondary source ro s anLocatio betvcen zero and twenty burnable poison rods.
The lack
^
e iilled with a source or burnable p l
A of sufficient clearance for these DUPLICATE DOCUMENT only at the core locations which c Entire document previously entered into system under:
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hh ANO No. of pages: _}}