ML19345C843
| ML19345C843 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 11/10/1980 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| References | |
| NUDOCS 8012080481 | |
| Download: ML19345C843 (1) | |
Text
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UNITED STATES I'
~i NUCLEAR REGULATORY COMMISSION 3
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REGION I 631 PARK AVENUE
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g,g KINO OF FRUSSIA, PENNSYLVANIA 19404 November 10, 1980 Docket Nos. 50-317 50-318 r
Baltimore Gas and Electric Company i
ATTN: Mr. A. E. Lundva11, Jr.
6~
Vice President, Sopply
~L P. O. Box 1475 R,
Baltimore, Maryland 21203 1
Gentlemen:
The enclosed IE Information Notice No. 80-41, Failure of S~ wing Check Valve in the Decay Heat Removal System at Davis-Besse Unit No.
1,
is forwarded to you for information.
No wHtten response is required.
If you desire additional information regarding this matter, please contact this office.
Sincerely,
~
,D _
1 Boyce H. Grier Director
Enclosures:
1.
IE Information Notice No. 80-41 2.
List of Recently Issued IE Information Notices CONTACT:
E. G. Greenaan (215-337-5267) cc w/encis:
R. M. Douglas, Manager, Quality Assurance L. 8. Russell, Plant Superintendent T. Sydnor, General Supervisor, Operations QA R. C. L. Olson, Principal Engineer J. A. Tiernan, Manager, Nuclear Power R. E. Denton, General Supervisor Training and Technical Services 8012080 M/
SSINS No.:
6835 Accession No.:
8008220260 UNITED STATES IN 80-41 NUCLEAR REGULATORY CCMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASNINGTON, D.C.
20555 l
November 10, 1980 IE Information Notice No. 80-41: FAILURE OF SWING CHECK VALVE IN THE DECAY HEAT REMOVAL SYSTEM AT DAVIS-BESSE UNIT M. 1 Descriotion of Circumstances:
On October,9,1980 the resident inspector at the Davis-Besse facility was informed that the licensee had performed leak rate tests and identified exces-sive leakage through Decay Heat Removal System check valve CF-30.
Valve CF-30 is the inboard one of two in-series check valves that is used to isolate the reactor coolant system from the low pressure decay heat removal system.
On further investigation the ifcensee found that the valve disc and arm had separated from the valve body and was lodged just under the valve cover plate.
The two 2 5/8 x 5/8 inch bolts and locking mechanism for the bolts that holds the arm to the valve body were missing and have not been located. The CF-30 valve is a 14-inch swing check valve manufactured by Velan Valve Corporation.
The cause of the failure has not been identified.
The test that was in progress when the ~ failure was identified was being con-ducted in response to a letter from -Darrell G. Eisenhut, Office of Nuclesr Reactor Regulations to all Light Water Reactor Licensees, LWR Primary Coolant System Pressure Isolation Valves, February 23, 1980.
This IE Information Notice is provided as an early notification of a possibly significant matter that is still under review by the NRC staff.
It is expected that recipients will review the information for possible appifcability to their facilities. No specific action or response is requested at this time.
If NRC evaluations so indicate, further ifcensee actions say be requested or regtsired.
No written response to this IE Information Notice is required.
If you have any questions regarding this matter, please contact the Director of the appropriate NRC Regional Office.
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IE Information Noticw No. 80-41 November 10, 1980 RECENTLY ISSUED IE INFORMATION NOTICES Information Subject Date Issued to Notice No.
Issued 80-40 Excessive Nitrogen 11/6/80 All holders of Supply Pressure a oower reactor OL Activates Safety-Relief or CP Valve Operation to Cause Reactor Depressurization 80-38 Cracking in Charging 10/30/80 All holders of Pump Casing Cladding a PWR power reactor OL or CP 80-37 Containment Cooler 10/24/80 All holders of a Laaks and Reactor power reactor OL Cavity Flooding at or CP Indian Point Unit 2 80-36 Failure of Steam 10/10/80 All holders of a Generator Support -
power reactor
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Bolting OL or CP 80-35 Leaking and Dislodged 10/10/80 All holders of a Iodine-125 Implant Category G or G1 Seeds Medical License 80-34 Boron OfTution of 9/26/80 All holders of a Reactor Coolant During PWR Power Reactor OL Steam Generator Decontamination 80-33 Determination of 9/15/80 All holders of Teletherapy Timer a teletherapy Accuracy license 80-32 Clarification of 9/12/80 All holders of Certain Requirements an NRC or Agreement for Exclucive-use State License Shipments of Radioactive Materials 80-31 Ma1 operation of Gould-8/27/80 All holders of Brown Boveri 480V-Type a power reactor K-6005 and K-Don 6005 OL or CP Circuit Breakers
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