ML19210E035
| ML19210E035 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 11/16/1979 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Goodwin C PORTLAND GENERAL ELECTRIC CO. |
| References | |
| NUDOCS 7911290188 | |
| Download: ML19210E035 (1) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION 5,\\$:7 /.
- REGION V 8
S fs-h 1990 N. CALIFORNIA BOULEVARD
,o SUITE 202, WALNUT CR E E K PLAZA
- e,e*
WALNUT CR EE K. CALIFORNIA 94596 flovember 16, 1979 Docket No. 50-344 Portland General Electric Company 121 S. W. Salmon Street Portland, Oregon 97204 Attention: Mr. Charles Goodwin, Jr.
Assistant Vice President Gentlemen:
The enclosed IE Circular flo. 79-22 is forwarded to you for information. flo written response is required. Should you have any questions related to your understanding of this matter, please contact this office.
Sincerely, 9t.t.bcd' RV R. H. Engelken U
Director
Enclosures:
1.
IE Circular No. 79-22 2.
Recently Issued IE Circulars cc w/ enclosures:
C. P. Yundt, PGE F. C. Gaidos, PGE 1435 109 7911290 /Sh
SSINS: 6830 Accession tio.:
7908220142 UNITED STATES
?!UCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D. C.
20555 November 16, 1979 IE Circular No. 79-22 STROKE TIPES FOR PONER OPERATED RELIEF VALVES Description of Circumstances:
Fast PWRs utilize power-operated relief valves (PORVs) to prevent overoressuriza--
tion of the reactor coolant systen when the reactor is at low tenperature. On April 13, during a cressure 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 tine is two seconds. As a result, the cres-sure transient did aooroach a cressure limit which is based on nil ductility considera tions. 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 stens were scored at that time, stroke times were satisfactory. The licensee and the valve manufacturer believe that the scored stems and the la-month interval without exercise resulted in poor perfomance of the PORVs.
Recorrended Actions for Licensees' Consideration:
All holders of PWR operating licenses or construction cemits should be aware of the cotential problem of the type discussed above. Because of the generic implications in this matter, it is recorrended that both licensees of operating facilities and holders of construction pemits 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 reauf re additional infomatinn reoardino these matters, contact the Director of the accrooriate NRC Reaional Office.
1435 110
IE Circular flo. 79-22 Enclosure November 16, 1979 RECE!lTLY ISSUED IE CIRCULARS Circular Subject Oate of Issued to flo.
Issue 79-21 Prevent'on of Unolanned 10/19/79 All holders of Pcwer Releases of Radioactivity Reactor OLs and cps 79-20 Failure Of GTE Sy?vania Relav 9/24/79 All utilities having a Tyce PM Bulletin 7305, Cataloo CP SU12-11-AC With A 120V AC Coil 79-19 Loose Locking Devices on 9/13/79 All Power Recctor Ingersoll-Rand Pumos Operating facilities and all utilities having a CP 79-18 Proper Installation of 9/10/79 All Holders of a Target Rock Safety-Relief Power Reactor OL Valves or CP 79-17 Contact Problem in S8-12 8/14/79 All Power Reactor Switches on General Electric Licensees with a CP Ccnoany Metalclad Circuit and/or OL Breakers 79-16 Excessive Radiation Exposures 8/16/79 All Radicarachy To 'fembers Of The General Public Licensees And A Radicaracher 79-15 Bursting of High Pressure Hose 9/8/79 All Materials Priority I, and "al# unction of Relief Fuel Cycle and Onerating Valve "0" Rina in Certain Self-Power Reactor Licensees Contained Breathino Apparatus 79-14 Unauthorized Procurerent and 7/13/79 All Medical Licensees Distribution of XE-133 except Teletheraphy Pedical Licensees and to all Radicoharmaceu-tical Sucoliers 1435 111