ML19225A498
| ML19225A498 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 06/06/1979 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Johari Moore SOUTHERN CALIFORNIA EDISON CO. |
| References | |
| NUDOCS 7907190426 | |
| Download: ML19225A498 (1) | |
Text
gn nrog o
UNITED STATES
'lb I
a (}e:p. ; g 8
) y, (
NUCLEAR REGULATORY COMMISSION nEGION V 0, ' MJM c
1990 N. CALIFORNIA BOULEVARD U
' %, ' N o
SulTE 202, WALNUT CREEK PLAZA WALNUT CR EEK, C/.itFORNIA 94596 June 6, 1979 Docht No. 50-206 Southern California Edison Company P. O. Bc). 800 2244 Walnut Grove Avenue Rosemead, California 91770 Attention: Mr. J. B. Moore Vice President Gentlemen:
Enclosed is supplement IE Bulletin 79-01 A.
It reqtiires action by ycu with regard to power reactor facilities with an operating license except for the 11 SEP plants which are listed in Enclosure 2.
This Bulletin is also being sent for information to the 11 SEP plants and all power reactor facilities with a construction permit.
No action or written response is required for construction permit facilities or the 11 SEP plants.
Should you have questions regarding this Bulletin or the actions required of you, please contact this office.
Sincerely, 7 O
/)
/ H. Enge// ESC?/,
LJ.lke f
Director
\\
Enclosure:
IE Bulletin No. 79-01 A cc w/ enclosure:
J. M. Curran, SCE J. T. Head, SCE
- cc')
\\D 790719 6 %
351 001
UtilTED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINCTON, D.C.
205S5 June 6, 1979 IE Bulletin No.79-01A SUPPLEMENT NO.79-01A TO IE BULLETIN 79 ENVIRONMENTAL QUALIFICAlION OF CLASS 1E EQUIPMENT (DEFICIENCIES IN THE ENVIRONMENTAL QUALIFICATION OF ASCO SOLEN 0ID VALVES)
Description of Circumstances:
Recently, a noncompliance report under J, CFP Part 21 was received by the NRC from the Henry Pratt Corrpany, manufacturer of butterfly valva which are installed in the primary containment at the Three Mile Island Unit 2 Nuclear Station. These butterfly valves are used for purge and exhaust purposes and are required to operate during accident conditions. The report diicus;es the use of an-unqualified solenoid valve for a safety-related valve function which requires operation under accident conditions. The solenoid valve in question is Catalogue No. HT-8331A45, manufactured by the Automatic Switch Company (ASCO) of Florham Park, New Jersey.
This pilot valve is used to pilot control the pneumatic valve actuators which are installed on the containment ventila-tion butterfly valves at this facility.
The def:ciency in these solenoid valves identified in the Part 21 Report concerns the parts mah of acetal plastic material. The acetal disc holder assembly and bottom plug in the pilot valve assembly are stated by ASLO to have a maximu.a oervice limit of 400,000 Rad integrated dosage and 200 degrees F temperature. Acccrding to ASCO, exposure of these acetal plastic parts to specified maximum environmental conditions may render the solenoid pilot valve inoperable which would cause the associated butterfly valve to malfunction.
Further investigation at ASCO by the NRC staff has revealed that the valve seals in most ASCO solenoid valves contain Buna "N" elastomer material, which reportedly has a maximum service li...it of 7,000,000 Rad integrated dosage and 180 degrees F temperature. The investigation further revealed that ASCO has available a line of qualified solenoid operated pilot valves (ASCO Catalogue No. NP-1) which have no plastic parts, utilize ethylene propylene or vitun elastomers and have a continuously energized # operating life of four years, under noimal embient conditions up to 140 degrees F.
According to the manu-facturer, at the end of this period, the coil, manual operator (optional fea-ture) and all resilient parts must be replaced.
These preventive maintenance instructions are specified in the installation and instruction bulletins whicn are provided to the purchaser with e'
' ~
"~ ~ " #eh
~-
The final items of concern identifie DUPLICATE DOCUMENT
]
application of Class "A", "B",
or "F]fn"t 1
t.
accident environment.
In this regar ument previously entered j
s
/0}0)
{l ANO No. of pages:
351 002,
)1
~_