Information Notice 1980-41, Failure of Swing Check Valve in Decay Heat Removal System at Davis Besse Unit No.1

Failure of Swing Check Valve in Decay Heat Removal System at Davis Besse Unit No.1

ML031180514
Person / Time
Site:	Davis Besse
Issue date:	11/10/1980
From:	NRC/OI
To:
References
IN-80-041, NUDOCS 8008220260
Download: ML031180514 (2)

p

SSINS No.: 6835 Accession No.:

8008220260

UNITED STATES IN 80-41 NUCLEAR REGULATORY COMMISSION

OFFICE OF INSPECTION AND ENFORCEMENT

WASHINGTON, D.C. 20555 November 10, 1980

IE Information Notice No. 80-41: FAILURE OF SWING CHECK VALVE IN THE DECAY

HEAT REMOVAL SYSTEM AT DAVIS-BESSE UNIT

NO. 1

Description 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 licensee 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 Nuclear

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 applicability to

their facilities. No specific action or response is requested at this time.

If NRC evaluations so indicate, further licensee actions may be requested

or required.

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.

IN 80-41 November 10, 1980

RECENTLY ISSUED

IE INFORMATION NOTICES

Information Date of

Notice No. Subject Issue Issued to

80-40 Failure Of Swing Check 11/10/80 All power facilities

Valve In The Decay Heat with and OL or CP

Removal System At Davis-Besse

Unit No. 1

80-39 Malfunctions Of Solenoid 10/31/80 All light water reactor

Valves Manufactured By facilities holding

Valcor Engineering Corporation power reactor OLs or CPs

80-38 - Cracking In Charging Pump 10/30/80 All PWR facilities

Casing Cladding with an OL or CP

80-37 Containment cooler leaks 10/24/80 All nuclear power

and reactor cavity facilities holding

flooding at Indian Point power reactor OLs

Unit 2 or CPs

80-36 Failure of Steam 10/10/80 All nuclear power

Generator Support Bolting reactor facilities

holding power reactor

OLs or CPs

80-35 Leaking and dislodged 10/10/80 All categories G and

Iodine-124 implant seeds G1 medical licensees

80-34 Boron dilution of reactor 9/26/80 All pressurized water

coolant during steam reactor facilities

generator decontamination holding power reactor OLs

80-33 Determination of teletherapy 9/15/80 All teletherapy

timer accuracy (G3) licensees

80-32 Clarification of certain 8/12/80 All NRC and agreement

requirements for Exclu- state licensees

sive-use shipments of

radioactive materials

80-31 Maloperation of Gould- 8/27/80 All light water reactor

Brown Boveri Type 480 facilities holding OLs

volt type K-600S and or CPs

K-DON 600S circuit

breakers

• Operating Licenses or Construction Permits