ML20203Q013
| ML20203Q013 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 04/14/1986 |
| From: | Van Brunt E ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR |
| To: | Kirsch D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| ANPP-36087-EEVB, DER-86-11, NUDOCS 8605080520 | |
| Download: ML20203Q013 (4) | |
Text
i, i
Arizona Nuclear Powergroject P o. box 52034
- PHOENIX, ARIZONA B$M2-0(RH
" f fiiQ:yg 14, 1986 April,ED87riiEVE/LAS/DRL-92.11 ANPP-3 U. S. Nuclear Regulatory Commission Region V 1450 Maria Lane - Suite 210 Walnut Creek, CA 94596-5368 Attention:
Mr. D. F. Kirsch, Act1 g Director 9
Division of R,eactor Safety and Projects Palo Verde Nuclear Genbrating Station (PVNGS)
Unit 3 Docket No. 50/530
Subject:
Interim Report - DER 86-11 A 50.55(e) Potentially Reportable Deficiency Relating To Qualification of the Skinner Solenoid Valves File: 86-006-216; 86-056-026; D 4.33.2
Reference:
Telephone Conversation between R. C. Sorenson and D. R. Larkin on March 14, 1986 (Initial Reportsbility - DER 86-11)
Dear Sir:
The NRC was notified of a potentially reportable deficiency in the referenced telephone conversation. At that time, it was estimated that a determination of l
reportability would be made within thirty (30) days.
(April 14, 1986)
Due to the extensive investigation and evaluation required, an Interim Report is attached.
It is now expected that this information will be finalized by i
May 16, 1986, at which time a complete report will be submitted.
I Very truly yours, 46 7 h
E. E. Van Brunt, Jr.
Executive Vice President Project Director EEVB/DRL/1df Idf/008/8611-Ltr cc: See Page Two 8605 ]O g g 0
i B
ffM
DER 86-11, Interim Report Mr. D. F. Kirsch Acting Director ANPP-36087-EEVB/LAS/DRL-92.11 April 14, 1986 Page 2 cc:
J. M. Taylor, Director Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Washington, D. C.
20555 A. C. Gehr (4141)
R. P. Zimmerman (6295)
Records Center Institute of Nuclear Power Operations 1100 Circle 75 Parkway - Suite 1500 Atlanta, Georgia 30339 a
r INTERIM REPORT - DER 86-11 POTENTIAL REPORTABLE DEFICIENCY ARIZONA NUCLEAR POWER PROJECT PVNGS UNIT 3 I.
Potential Problem Skinner Solenoid Valves (Model No. V5H65600) were qualified for operation a.
at 125VDC for a period of 5.5 years by test and analysis that did not consider continuous energization which results in higher operating temper-atures than considered in the aging calculations (Reference C).
b.
These solenoid valves, which are used on the Main Steam Isolation Valves (MSIV's) and the bhin Feedwater Isolation Valves (MFIV's), are contin-uously energized (References A & B).
Consequently, the qualified life, based on the original calculations, of these solenoid valves is unknown.
The FBIV's and MFIV's are supplied by the Anchor Darling Valve Company (ADVC).
c.
This oversight was discovered during the evaluation of Class 1E equipment qualification documentation.
Engineering is presently investigating the effect on Class IE equipment for continuous operation of the Class 1E 125VDC power supply at 135VDC instead of 125VDC.
The Skinner Solenoid Valves are used in all three units at ANPP; however, to date no failures involving these valves have occurred.
II.
Approach to and Status of Proposed Resolution ADVC evaluated this condition and concluded:
Based upon the original qualification report (Reference C), the valve's a.
qualified life for a continuously energized coil is very short (Reference D).
b.
Electrical failure of the coil, due to excessive temperature, would cause it to deenergize which would result in closure of the MSIV/MFIV (Reference D). [However, mechanical failure of the coil, due to heating, could cause binding which might prohibit closure. ]
The functions of the MSIV's/MFIV's are to:
Isolate the Steam Generators and Main Steam lines in the event of a pipe a.
rupture.
b.
Isolate the Containment during a Design Basis Event.
Consequently, the circuit design for coil energization is fail-safe from an electrical standpoint only. Their present use, on an interim basis, in Units 1 and 2, however, is justified by a preliminary analysis which demon-strates approximately 5 years of qualified life, continuously energized, based on margin of the original testing and analysis.
Idf/001/IR86-11
au a
4.
s i
j.
Page Two INTERIM REPORT.- DER 86-11 I
P i
4 III. ' Projected Completion of Corrective Action
-and Submittal of the Final Report i
l
' Engineering is currently're-evaluating the qualified life of the Skinner sole-I noid valves now in use, and corrective action, if required, is contingent upon the findings. The Final Report is forecast for May 16, 1986, t
REFERENCES ~
d j
A.
M234A-57-3 B.
M234A-60-2 C.
D.
ADVC Letter dated March 12, 1986 (MIC 253679) i t
'f
).j-1
?-
i I
i i
j i
l l
J 4,
I 1
4 4
i Idf/001/IR8611p2-i
.,.n.-.,
.,-.,,r..,,
...s.,-.,
, - -.--.. - -. ~
--. - - -.