ML19210E432

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Forwards IE Circular 79-22, Stroke Times for Power Operated Relief Valves. No Response Required
ML19210E432
Person / Time
Site: 05000363
Issue date: 11/16/1979
From: Grier B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To: Finfrock I
JERSEY CENTRAL POWER & LIGHT CO.
References
NUDOCS 7912050030
Download: ML19210E432 (1)


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Docket No. 50-363 NOV 161979 Jersey Central Power & Light Company ATTN:

Mr. I. R. Finfrock, Jr.

Vice Pres'desat 260 Cherry Hill Foad Parsippany, New.iersey 07054 Gentlemen:

The enclosed IE Circular No. 79-22, " Stroke Times for Power Operated Relief Valves," is forwarded to you for information.

No written response is required.

Should you have any questions related to your understanding of this matter, please contact this office.

Sincerely, T

424sfepu

_ Boyce H. Grier Director

Enclosures:

1.

IE Circular No. 79-22 2.

List of Recently Issued Circulars CONTACT:

D. L. Caphton (L5-337-5263) cc w/encls:

M. K. Pastor, Project Manager 1500 243 79120500 30

ENCLOSURE 1 SSINS:

6830 Accession No.:

79 2201 ?

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UNITED STATES so NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C.

20555 IE Circular No. 79-22 Date:

November 16, 1979 Page 1 of 1 STROKE TIMES FOR POWER OPERATED RELIEF VALVES Description of Circumstances:

Most PWRs utilize power-operated relief valves (PORVs) to prevent overpressuriza-tion of the reactor coolant system when the reactor is at low temperature.

On April 13, during a pressure transient at Robinson 2, the PORVs did not function as rapidly as intended.

The estimated stroke time for the PORVs was three to five seconds whereas the intended stroke time is two seconds.

As a result, the pressure transient did approach a pressure limit which is based on nil ductility considerations.

Prior to April 13, the PORVs had not been used or exercised since February, 1978, when they had been repacked and stroked.

Although the valve stems were scored at that time, stroke times were satisfactory.

The licensee and the valve manufacturer believe that the scored stems and the 14-month interval without exercise resulted in poor performance of the PORVs.

Recommended Actions for L:censees' Consideration:

All holders of PWR operating licenses or construction permits shculd be aware of the potential proolem of the type discussed above.

Because of the generic implications in this matter, it is recommended that both licensees of operating facilities and holders of construction permits conduct a review to determine if periodic serveillance of PORVs is necessary to assure that the PORVs will perform as intended.

No written response to this Circular is required.

If you require additional information regarding these matters, contact the Director of the appropriate NRC Regional Office.

1500 m

e ENCLOSURE 2 IE Circular No. 79-22 Date:

November 16, 1979 Page 1 of 1 RECENTLY ISSUED CIRCULARS Ci-cular Subject First Date Issued To No.

,.f Issue 79-15 Bursting of High Pres-8/8/79 All Materials Priority sure Hose and Malfunc-I, Fuel Cycle and Opera-tion of Relief Valve "0" ting Power Reactor Ring in Certain Self-Licensees Contained Breathing Apparatus 79-16 Excessive Radiation 8/16/79 All Radiography Exposures to Mer..bers 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 OL General Electric or CP Metalclad Circuit Breakers 79-18 Proper Installation of 9/10/79 All Power Reactor Target Rock Safety-Licensens 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 1500 245

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